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Liu Z, Skrzypek G, Batelaan O, Guan H. Rain use efficiency gradients across Australian ecosystems. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 933:173101. [PMID: 38734114 DOI: 10.1016/j.scitotenv.2024.173101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/29/2024] [Accepted: 05/07/2024] [Indexed: 05/13/2024]
Abstract
Rain use efficiency (RUE) quantifies the ecosystem's capacity to use precipitation water to assimilate atmospheric CO2. The spatial distribution of RUE and its drivers across the Australian continent is largely unknown. This knowledge gap limits our understanding of the possible contribution of Australian ecosystems to global carbon assimilation. This study investigates the spatial distribution of RUE across diverse terrestrial ecosystems in Australia. The results show that RUE ranges from 0.43 (1st percentile) to 3.10 (99th percentile) g C m-2 mm-1 with a continental mean of 1.19 g C m-2 mm-1. About 68 % of the spatiotemporal variability of RUE can be explained by a multiple linear regression model primarily contributed by climatic predictors. Benchmarked by the model estimation, drainage-diverging/converging landscapes tend to have reduced/increased RUE. The model also revealed the impact of increasing atmospheric CO2 concentration on RUE. The continental mean RUE would increase by between 29.3 and 64.8 % by the end of this century under the SSP5-8.5 scenario in which the CO2 concentration is projected to double from the present level. This increase in projected RUE is attributed to the assumed greening effect of increasing CO2 concentration, which does not consider the saturation of CO2 fertilisation effect and the warming effect on increasing wildfire occurrence. Under the SSP1-2.6 scenario, RUE would decrease by about 7 %. This study provides baseline RUEs of various ecosystems in Australia for investigating the impacts of human interferences and climate change on the capacity of Australian vegetation to assimilate atmospheric CO2 under given precipitation.
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Affiliation(s)
- Zhongli Liu
- National Centre for Groundwater Research and Training, College of Science and Engineering, Flinders University, Adelaide, SA, Australia
| | - Grzegorz Skrzypek
- West Australian Biogeochemistry Centre, School of Biological Sciences, The University of Western Australia, Perth, WA, Australia
| | - Okke Batelaan
- National Centre for Groundwater Research and Training, College of Science and Engineering, Flinders University, Adelaide, SA, Australia
| | - Huade Guan
- National Centre for Groundwater Research and Training, College of Science and Engineering, Flinders University, Adelaide, SA, Australia.
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2
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Xiao Y, Chen T, Chen X, Yang Y, Wang S, Zhou S. CMIP6 ESMs overestimate greening and the photosynthesis trends in Dryland East Asia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 937:173432. [PMID: 38797402 DOI: 10.1016/j.scitotenv.2024.173432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 04/05/2024] [Accepted: 05/20/2024] [Indexed: 05/29/2024]
Abstract
The Dryland East Asia (DEA) is one of the largest inland arid regions, and vegetation is very sensitive to climate change. The complex environment in DEA with defects of modeling construction make it difficult to simulate and predict changes in vegetation structure and productivity. Here, we use the emergent constraint (EC) method to constrain the future interannual leaf area index (LAI) and gross primary productivity (GPP) trends in DEA, under four scenarios of the latest Sixth Coupled Model Intercomparison Project (CMIP6) model ensemble. LAI and GPP increase in all scenarios in the near term (2015-2050), with continued growth in SSP370 and SSP585 and stasis in SSP126 and SSP245 in the far term (2051-2100). However, after building effective EC relationships, the constrained increasing trends of LAI (GPP) are reduced by 43.5 %-53.9 % (30.5 %-50.0 %) compared with the uncertainties of the original ensemble, which are reduced by 10.0 %-45.7 % (4.6 %-34.3 %). We also extend the EC in moving windows and grid cells, further strengthening the robustness of the constraints, especially by illustrating spatial sources of these emergent relationships. Overestimations of LAI and GPP trends suggest that current CMIP6 models may be insufficient to capture the complex relationships between climate change and vegetation dynamics in DEA; however, these models can be adjusted based on established emergent relationships.
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Affiliation(s)
- Yinmiao Xiao
- School of Geographical Sciences, Nanjing University of Information Science and Technology, Nanjing, China
| | - Tiexi Chen
- School of Geographical Sciences, Nanjing University of Information Science and Technology, Nanjing, China; Qinghai Provincial Key Laboratory of Plateau Climate Change and Corresponding Ecological and Environmental Effects, Qinghai Institute of Technology, Xining, China; School of Geographical Sciences, Qinghai Normal University, Xining, China.
| | - Xin Chen
- School of Geographical Sciences, Nanjing University of Information Science and Technology, Nanjing, China
| | - Yang Yang
- Qinghai Provincial Key Laboratory of Plateau Climate Change and Corresponding Ecological and Environmental Effects, Qinghai Institute of Technology, Xining, China; School of Geographical Sciences, Qinghai Normal University, Xining, China
| | - Shengzhen Wang
- Qinghai Provincial Key Laboratory of Plateau Climate Change and Corresponding Ecological and Environmental Effects, Qinghai Institute of Technology, Xining, China; School of Geographical Sciences, Qinghai Normal University, Xining, China
| | - Shengjie Zhou
- School of Geographical Sciences, Nanjing University of Information Science and Technology, Nanjing, China
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3
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Dong S, Du S, Wang XC, Dong X. Terrestrial vegetation carbon sink analysis and driving mechanism identification in the Qinghai-Tibet Plateau. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 360:121158. [PMID: 38781875 DOI: 10.1016/j.jenvman.2024.121158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Revised: 04/08/2024] [Accepted: 05/10/2024] [Indexed: 05/25/2024]
Abstract
The estimation of terrestrial carbon sinks in the Qinghai-Tibet Plateau (QTP) still faces significant uncertainties, and the spatiotemporal dynamics of terrestrial carbon sinks along altitudinal gradients remain unexplored. Moreover, the driving mechanisms of terrestrial carbon sinks at the watershed scale in the QTP continue to be lacking. To address these research gaps, based on multi-source remote sensing data and meteorological data, this study calculated the Net Ecosystem Productivity (NEP) in the QTP from 2000 to 2020 using the Modis NPP-soil respiration model. Through the coefficient of variation (CV), the Mann-Kendall test (MK), and the spatial autocorrelation methods, the spatial distribution pattern and spatiotemporal trends of NEP were investigated. Employing a pixel accumulation method, the variation of NEP along altitudinal gradients was explored. Grey relation analysis, Pearson correlation analysis, and Geographical detector (GD) were used to investigate the driving mechanisms of NEP at the watershed scale. Results showed that: (1) the terrestrial ecosystem in the QTP served as a carbon sink, which produced a total of 2.04 Pg C from 2000 to 2020, and the multi-year average of total carbon sinks was 96.92 Tg C; (2) the spatial distribution of NEP shows a decreasing change from southeast to northwest, and the clustering characteristic of NEP is significant at the watershed scale; (3) the elevation of 4507 m we proposed is likely to be a key threshold for biophysical processes of the terrestrial ecosystems in the QTP; (4) the fluctuation and change trend of carbon sources and carbon sinks show significant differences between the East and West; (5) at the watershed scale, precipitation and temperature play a dominant role in the variation of NEP, while the impact of human activities on NEP variation is weak. Our study aims to address the existing knowledge gaps and provide valuable insights into the management of terrestrial carbon sinks in QTP.
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Affiliation(s)
- Shuheng Dong
- Beijing Key Laboratory of Traditional Chinese Medicine Protection and Utilization, Faculty of Geographical Science, Beijing Normal University, Beijing, China; School of Natural Resources, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
| | - Shushan Du
- Beijing Key Laboratory of Traditional Chinese Medicine Protection and Utilization, Faculty of Geographical Science, Beijing Normal University, Beijing, China; School of Natural Resources, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
| | - Xue-Chao Wang
- School of Natural Resources, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China; State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China.
| | - Xiaobin Dong
- School of Natural Resources, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China; State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
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4
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Wang B, Smith B, Waters C, Feng P, Liu DL. Modelling changes in vegetation productivity and carbon balance under future climate scenarios in southeastern Australia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 924:171748. [PMID: 38494011 DOI: 10.1016/j.scitotenv.2024.171748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 03/10/2024] [Accepted: 03/14/2024] [Indexed: 03/19/2024]
Abstract
Australia, characterized by extensive and heterogeneous terrestrial ecosystems, plays a critical role in the global carbon cycle and in efforts to mitigate climate change. Prior research has quantified vegetation productivity and carbon balance within the Australian context over preceding decades. Nonetheless, the responses of vegetation and carbon dynamics to the evolving phenomena of climate change and escalating concentrations of atmospheric carbon dioxide remain ambiguous within the Australian landscape. Here, we used LPJ-GUESS model to assess the impacts of climate change on Gross Primary Productivity (GPP) and Net Biome Productivity (NBP) of carbon for the state of New South Wales (NSW) in southeastern Australia. LPJ-GUESS simulations were driven by an ensemble of 27 global climate models under different emission scenarios. We investigated the change of GPP for different vegetation types and whether NSW ecosystems will be a net sink or source of carbon under climate change. We found that LPJ-GUESS successfully simulated GPP for the period 2003-2021, demonstrating a comparative performance with GPP derived from upscaled eddy covariance fluxes (R2 = 0.58, nRMSE = 14.2 %). The simulated NBP showed a larger interannual variation compared with flux data and other inversion products but could capture the timing of rainfall-driven carbon sink and source variations in 2015-2020. GPP would increase by 10.3-19.5 % under a medium emission scenario and 19.7-46.8 % under a high emission scenario. The mean probability of NSW acting as a carbon sink in the future showed a small decrease with a large uncertainty with >8 of the 27 climate models indicating an increased potential for carbon sink. These findings emphasize the significance of emission scenarios in shaping future carbon dynamics but also highlight considerable uncertainties stemming from different climate projections. Our study represents a baseline for understanding natural ecosystem dynamics and their key role in governing land carbon uptake and storage in Australia.
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Affiliation(s)
- Bin Wang
- NSW Department of Primary Industries, Wagga Wagga Agricultural Institute, Wagga Wagga, NSW 2650, Australia; Gulbali Institute for Agriculture, Water and Environment, Charles Sturt University, Wagga Wagga, NSW 2678, Australia.
| | - Benjamin Smith
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia; University of Lund, Department of Physical Geography and Ecosystem Science, 223 62 Lund, Sweden
| | - Cathy Waters
- GreenCollar, The Rocks, Sydney, NSW 2000, Australia; Formerly NSW Department of Primary Industries, Dubbo, NSW 2830, Australia
| | - Puyu Feng
- College of Land Science and Technology, China Agricultural University, Beijing 100193, China
| | - De Li Liu
- NSW Department of Primary Industries, Wagga Wagga Agricultural Institute, Wagga Wagga, NSW 2650, Australia; Gulbali Institute for Agriculture, Water and Environment, Charles Sturt University, Wagga Wagga, NSW 2678, Australia; Climate Change Research Centre and ARC Centre of Excellence for Climate Extremes, University of New South Wales, Sydney, NSW 2052, Australia
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5
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Chai Y, Hu Y. Characteristics and drivers of vegetation productivity sensitivity to increasing CO 2 at Northern Middle and High Latitudes. Ecol Evol 2024; 14:e11467. [PMID: 38799397 PMCID: PMC11116762 DOI: 10.1002/ece3.11467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 05/01/2024] [Accepted: 05/08/2024] [Indexed: 05/29/2024] Open
Abstract
Understanding and accurately predicting how the sensitivity of terrestrial vegetation productivity to rising atmospheric CO2 concentration (β) is crucial for assessing carbon sink dynamics. However, the temporal characteristics and driving mechanisms of β remain uncertain. Here, observational and CMIP6 modeling evidence suggest a decreasing trend in β at the Northern Middle and High Latitudes during the historical period of 1982-2015 (-0.082 ± 0.005% 100 ppm-1 year-1). This decreasing trend is projected to persist until the end of the 21st century (-0.082 ± 0.005% 100 ppm-1 year-1 under SSP370 and -0.166 ± 0.006% 100 ppm-1 year-1 under SSP585). The declining β indicates a weakening capacity of vegetation to mitigate warming climates, posing challenges for achieving the temperature goals of the Paris Agreement. The rise in vapor pressure deficit (VPD), that triggers stomata closure and weakens photosynthesis, is considered as the dominated factor contributing to the historical and future decline in β, accounting for 62.3%-75.2% of the effect. Nutrient availability and water availability contribute 15.7%-21.4% and 8.5%-16.3%, respectively. These findings underscore the significant role of VPD in shaping terrestrial carbon sink dynamics, an aspect that is currently insufficiently considered in many climate and ecological models.
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Affiliation(s)
- Yuanfang Chai
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical ScienceBeijing Normal UniversityBeijingChina
| | - Yong Hu
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth EnvironmentChinese Academy of SciencesXi'anChina
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Teng D, Gong X, He X, Wang J, Lv G, Wang J, Yang X. Impact of meteorological variability on diurnal and seasonal net ecosystem productivity in a desert riparian forest ecosystem. FRONTIERS IN PLANT SCIENCE 2024; 15:1332192. [PMID: 38699537 PMCID: PMC11063279 DOI: 10.3389/fpls.2024.1332192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 04/03/2024] [Indexed: 05/05/2024]
Abstract
The desert riparian forests are susceptible to meteorological changes and contribute significantly to the net ecosystem productivity (NEP) variations of arid ecosystems. However, the responsive patterns of their NEP variations to the meteorological variabilities remain inadequately comprehended. To address this gap, we utilized seven years of eddy covariance flux measurements in a representative desert riparian forest to investigate the NEP variations and its response to changing meteorological factors across diverse temporal scales. The results revealed significant periodic variations in half-hourly NEP, with dominant cycles spanning from five hours to one year, with a principal oscillation period of one day. Key meteorological factors including global solar radiation (Rg), relative humidity (RH), air temperature (Ta), soil temperature (Ts), and vapor pressure deficit (VPD) exhibited synchronization with NEP on daily scales. This synchronization, coupled with the observed one-day periodic NEP variations, provides robust evidence supporting the existence of a circadian rhythm in the ecosystem carbon exchange of desert riparian forest regulated by meteorological conditions. Seasonal patterns were significant in the impact of Rg phase, Ta diurnal amplitude, and VPD diurnal amplitude on NEP diurnal amplitude and phase. The NEP diurnal amplitude significantly, directly, and positively affected daily NEP in both the dormant and growing seasons, whereas its phase yielded significant negative effects (P< 0.05). The averages, amplitudes, and phases of diurnal meteorological conditions controlled the daily NEP by regulating NEP diurnal amplitude and phase. These findings provide evidence that the variability in circadian rhythms, caused by the increase in diurnal Ta and VPD, significantly impact the daily NEP at an ecosystem scale. This study enriches our comprehension of the meteorological mechanisms governing diurnal and seasonal carbon uptake dynamics within desert riparian forests, providing fresh insights into the direct and indirect roles of climate change in shaping patterns of ecosystem carbon exchange.
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Affiliation(s)
- Dexiong Teng
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Xuewei Gong
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Xuemin He
- College of Ecology and Environment, Xinjiang University, Urumqi, China
- Xinjiang Jinghe Observation and Research Station of Temperate Desert Ecosystem, Ministry of Education, Urumqi, China
| | - Jingzhe Wang
- School of Artificial Intelligence, Shenzhen Polytechnic University, Shenzhen, China
| | - Guanghui Lv
- College of Ecology and Environment, Xinjiang University, Urumqi, China
- Xinjiang Jinghe Observation and Research Station of Temperate Desert Ecosystem, Ministry of Education, Urumqi, China
| | - Jinlong Wang
- College of Ecology and Environment, Xinjiang University, Urumqi, China
- Xinjiang Jinghe Observation and Research Station of Temperate Desert Ecosystem, Ministry of Education, Urumqi, China
| | - Xiaodong Yang
- Department of Geography & Spatial Information Technology, Ningbo University, Ningbo, China
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Khairoun A, Mouillot F, Chen W, Ciais P, Chuvieco E. Coarse-resolution burned area datasets severely underestimate fire-related forest loss. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 920:170599. [PMID: 38309343 DOI: 10.1016/j.scitotenv.2024.170599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/28/2024] [Accepted: 01/29/2024] [Indexed: 02/05/2024]
Abstract
Global coarse-resolution (≥250 m) burned area (BA) products have been used to estimate fire related forest loss, but we hypothesised that a significant part of fire impacts might be undetected because of the underestimation of small fires (<100 ha), especially in the tropics. In this paper, we analysed fire-related forest cover loss in sub-Saharan Africa (SSA) for 2016 and 2019 based on a BA product generated from Sentinel-2 data (20 m), which was observed to have significantly lower omission errors than the coarse-resolution BA products. Using these higher resolution BA datasets, we found that fires contribute to >46 % of total forest losses over SSA, more than twice the estimates from coarse-resolution BA products. In addition, burned forest areas showed more than twofold likelihood of subsequent loss compared to unburned ones. In moist tropical forests, the most fire-vulnerable biome, burning had even six times more chance to precede forest loss than unburned areas. We also found that fire-related characteristics, such as fire size and season, and forest fragmentation play a major role in the determination of tree cover fate. Our results reveal that medium-resolution BA detects more fires in late fire season, which tend to have higher impact on forests than early season ones. On the other hand, small fires represented the major driver of forest loss after fires and the vast majority of these losses occur in fragmented landscapes near forest edge (<260 m). Therefore medium-resolution BA products are required to obtain a more accurate evaluation of fire impacts in tropical ecosystems.
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Affiliation(s)
- Amin Khairoun
- Universidad de Alcalá, Environmental Remote Sensing Research Group, Department of Geology, Geography and the Environment, Colegios 2, 28801 Alcalá de Henares, Spain
| | - Florent Mouillot
- Centre d'Ecologie Fonctionnelle et Evolutive CEFE, UMR 5175, CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, IRD, 1919 Route de Mende, 34293 Montpellier Cedex 5, France
| | - Wentao Chen
- Centre d'Ecologie Fonctionnelle et Evolutive CEFE, UMR 5175, CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, IRD, 1919 Route de Mende, 34293 Montpellier Cedex 5, France
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Emilio Chuvieco
- Universidad de Alcalá, Environmental Remote Sensing Research Group, Department of Geology, Geography and the Environment, Colegios 2, 28801 Alcalá de Henares, Spain.
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Flo V, Joshi J, Sabot M, Sandoval D, Prentice IC. Incorporating photosynthetic acclimation improves stomatal optimisation models. PLANT, CELL & ENVIRONMENT 2024. [PMID: 38589983 DOI: 10.1111/pce.14891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 03/04/2024] [Accepted: 03/08/2024] [Indexed: 04/10/2024]
Abstract
Stomatal opening in plant leaves is regulated through a balance of carbon and water exchange under different environmental conditions. Accurate estimation of stomatal regulation is crucial for understanding how plants respond to changing environmental conditions, particularly under climate change. A new generation of optimality-based modelling schemes determines instantaneous stomatal responses from a balance of trade-offs between carbon gains and hydraulic costs, but most such schemes do not account for biochemical acclimation in response to drought. Here, we compare the performance of six instantaneous stomatal optimisation models with and without accounting for photosynthetic acclimation. Using experimental data from 37 plant species, we found that accounting for photosynthetic acclimation improves the prediction of carbon assimilation in a majority of the tested models. Photosynthetic acclimation contributed significantly to the reduction of photosynthesis under drought conditions in all tested models. Drought effects on photosynthesis could not accurately be explained by the hydraulic impairment functions embedded in the stomatal models alone, indicating that photosynthetic acclimation must be considered to improve estimates of carbon assimilation during drought.
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Affiliation(s)
- Victor Flo
- Department of Life Sciences, Georgina Mace Centre for the Living Planet, Imperial College London, Silwood Park Campus, Ascot, UK
- Departament de Biologia Animal, Biologia Vegetal i Ecologia, Univ Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Jaideep Joshi
- Department of Geosciences, Institute of Geography, University of Bern, Bern, Switzerland
- Oeschger Centre for Climate Change Research, Faculty of Science, University of Bern, Bern, Switzerland
- Advancing Systems Analysis Program, International Institute for Applied Systems Analysis, Laxenburg, Austria
- Complexity Science and Evolution Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, Japan
| | - Manon Sabot
- ARC Centre of Excellence for Climate Extremes, Sydney, New South Wales, Australia
- Climate Change Research Centre, University of New South Wales, Sydney, New South Wales, Australia
- Department of Biogeochemical Signals, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - David Sandoval
- Department of Life Sciences, Georgina Mace Centre for the Living Planet, Imperial College London, Silwood Park Campus, Ascot, UK
| | - Iain Colin Prentice
- Department of Life Sciences, Georgina Mace Centre for the Living Planet, Imperial College London, Silwood Park Campus, Ascot, UK
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Wang A, Gao X, Zhou Z, Siddique KHM, Yang H, Wang J, Zhang S, Zhao X. A novel index for vegetation drought assessment based on plant water metabolism and balance under vegetation restoration on the Loess Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 918:170549. [PMID: 38309335 DOI: 10.1016/j.scitotenv.2024.170549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 01/15/2024] [Accepted: 01/27/2024] [Indexed: 02/05/2024]
Abstract
Vegetation is vital to the ecosystem, contributing to the global carbon balance, but susceptible to the impacts of climate change. Monitoring vegetation drought remains challenging due to the lack of widely accepted drought indices. This study focused on vegetation, and simulated the vegetation suitable water demand and soil available water supply (calculated by Remote-sensing-based Water Balance Assessment Tool model). The standardized Vegetation Water deficit Index (SVWDI) was established by calculating the vegetation water deficit, which reflects the response of vegetation to drought. We examined the spatiotemporal evolution of vegetation drought on the Loess Plateau and evaluated the applicability of standardized vegetation water deficit index. Our findings revealed that the standardized vegetation water deficit index demonstrated an overall upward trend across different time scales from 1991 to 2020. Drought conditions were concentrated in the first 20 years of the study period, but vegetation drought on the Loess Plateau has been alleviated in the past decade. Moreover, as the time scale extended, the trend of SVWDI generally decreased, with approximately 49.50 % (1-month scale), 46.66 % (3-month scale), 47.08 % (12-month scale), and 32.16 % (24-month scale) of the grid areas experiencing increased SVWDI. The correlation between SVWDI and tree-ring width index (TRWI) performed well under all precipitation gradients, but the Palmer drought severity index (PDSI) was only highly correlated with TRWI in regions with low precipitation. In terms of the relationship with vegetation health, SVWDI demonstrated the highest correlation with the normalized difference vegetation index (NDVI) across different time scales, followed by PDSI and standardized precipitation evapotranspiration index (SPEI). This study provides insights into the evolution of vegetation drought in response to climate change. The findings can guide initiatives such as returning farmland to forest and grassland on the Loess Plateau to aid climate change adaptation strategies.
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Affiliation(s)
- Ai Wang
- College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A&F University, Yangling 712100, Shaanxi Province, China
| | - Xuerui Gao
- Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi 712100, China.
| | - Zeyu Zhou
- China Water Resources Beifang Investigation, Design and Research Co. Ltd, Tianjin 300222, China
| | - Kadambot H M Siddique
- The UWA Institute of Agriculture, The University of Western Australia, Perth, WA, Australia
| | - Hao Yang
- College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A&F University, Yangling 712100, Shaanxi Province, China
| | - Jichao Wang
- College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A&F University, Yangling 712100, Shaanxi Province, China
| | - Shuyu Zhang
- School of Environmental Science and Engineering, Southern University of Science and Technology, China
| | - Xining Zhao
- Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi 712100, China.
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Tripathi IM, Mahto SS, Kushwaha AP, Kumar R, Tiwari AD, Sahu BK, Jain V, Mohapatra PK. Dominance of soil moisture over aridity in explaining vegetation greenness across global drylands. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 917:170482. [PMID: 38296067 DOI: 10.1016/j.scitotenv.2024.170482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 01/16/2024] [Accepted: 01/24/2024] [Indexed: 02/04/2024]
Abstract
Drylands are one of the most sensitive areas to climate change. Despite being characterized by water scarcity and low precipitation, drylands support a wide range of green biodiversity and nearly 40 % of the global population. However, the climate change impacts on dryland characteristics and vegetation dynamics are debatable as the reasons remain poorly understood. Here, we use hydro-meteorological variables from ERA5 reanalysis and GIMMS-NDVI to analyze the changes in dryland aridity and vegetation greenness in the eight selected global dryland regions. The total dryland area (excluding hyperarid) has increased by 12 %, while arid, semiarid, and dry sub-humid areas have increased by 10.5 %, 8 %, and 25 %, respectively. We find a significant increase in aridity in drylands across the globe, except for South Asia. A decrease (increase) in precipitation is the major driver for a significant increase (decrease) in dryland aridity, with a notable contribution from climate warming. Despite decreasing trends in precipitation, vegetation greenness has significantly increased in most dryland regions due to increased soil moisture. Cropland expansion in Europe, Asia, and Australia resulted in the maximum increase in NDVI (Normalized Difference Vegetation Index) in dryland regions. The highest increase, with a ΔNDVI of 0.075, was observed in South Asia. The enhanced vegetation greenness observed is attributed to the expansion of croplands in recent decades, which has increased soil moisture. Overall, we show that monitoring soil moisture variability can provide a more robust explanation for vegetation greenness in the global drylands than aridity change. Moreover, human interventions of climatic alteration through land use change practices, such as cropland expansion, cannot be ignored while explaining the ecosystem dynamics of the drylands.
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Affiliation(s)
- Indra Mani Tripathi
- Department of Earth Sciences, Indian Institute of Technology (IIT) Gandhinagar, India.
| | - Shanti Shwarup Mahto
- Department of Earth Sciences, Indian Institute of Technology (IIT) Gandhinagar, India
| | - Anuj Prakash Kushwaha
- Department of Earth Sciences, Indian Institute of Technology (IIT) Gandhinagar, India
| | - Rahul Kumar
- Department of Civil, Environmental and Geomatics Engineering, Florida Atlantic University, USA
| | - Amar Deep Tiwari
- Department of Civil and Environmental Engineering, Michigan State University, USA
| | - Bidhan Kumar Sahu
- Department of Civil Engineering, Indian Institute of Technology (IIT) Gandhinagar, India
| | - Vikrant Jain
- Department of Earth Sciences, Indian Institute of Technology (IIT) Gandhinagar, India
| | - Pranab Kumar Mohapatra
- Department of Civil Engineering, Indian Institute of Technology (IIT) Gandhinagar, India
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11
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Mu Y, Jia X, Ye Z, Zha T, Guo X, Black TA, Zhang Y, Hao S, Han C, Gao S, Qin S, Liu P, Tian Y. Dry-season length affects the annual ecosystem carbon balance of a temperate semi-arid shrubland. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 917:170532. [PMID: 38296104 DOI: 10.1016/j.scitotenv.2024.170532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 12/25/2023] [Accepted: 01/26/2024] [Indexed: 02/03/2024]
Abstract
Semi-arid ecosystems have been shown to dominate over tropical forests in determining the trend and interannual variability of land carbon (C) sink. However, the magnitude and variability of ecosystem C balance remain largely uncertain for temperate semi-arid shrublands at the decadal scale. Using eddy-covariance and micro-meteorological measurements, we quantified the interannual variation in net ecosystem production (NEP) and its components, gross primary production (GPP) and ecosystem respiration (Reco, i.e., the sum of autotrophic and heterotrophic respiration), in a semi-arid shrubland of the Mu Us Desert, northern China during 2012-2022. This shrubland was an overall weak C sink over the 11 years (NEP = 12 ± 46 g C m-2 yr-1, mean ± SD). Annual NEP ranged from -66 to 77 g C m-2 yr-1, with the ecosystem frequently switching between being an annual C sink and a C source. GPP was twice as sensitive as Reco to prolonged dry seasons, leading to a close negative relationship between annual NEP and dry-season length (R2 = 0.80, P < 0.01). Annual GPP (R2 = 0.51, P = 0.01) and NEP (R2 = 0.58, P < 0.01) were positively correlated with annual rainfall. Negative annual NEP (the ecosystem being a C source) tended to occur when the dry season exceeded 50 d yr-1 or rainfall dropped below 280 mm yr-1. Increases in dry-season length strengthened the effects of low soil moisture relative to high vapor pressure deficit in constraining NEP. Both GPP and NEP were more closely correlated with C uptake amplitude (annual maximum daily values) than with C uptake period. These findings indicate that dry-season extension under climate change may reduce the long-term C sequestration in semi-arid shrublands. Plant species adapted to prolonged dry seasons should be used in ecosystem restoration in the studied area to enhance ecosystem functions.
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Affiliation(s)
- Yanmei Mu
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
| | - Xin Jia
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China; State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing 100083, China; Key Laboratory for Soil and Water Conservation, National Forestry and Grassland Administration, Beijing Forestry University, Beijing 100083, China.
| | - Ziqi Ye
- School of Natural Sciences, Laurentian University, Sudbury, ON P3E 2C6, Canada
| | - Tianshan Zha
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China; State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing 100083, China; Key Laboratory for Soil and Water Conservation, National Forestry and Grassland Administration, Beijing Forestry University, Beijing 100083, China
| | - Xulin Guo
- Department of Geography and Planning, University of Saskatchewan, Saskatoon, SK S7N 5C8, Canada
| | - T Andrew Black
- Biometeorology and Soil Physics Group, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Yuqing Zhang
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China; State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing 100083, China; Key Laboratory for Soil and Water Conservation, National Forestry and Grassland Administration, Beijing Forestry University, Beijing 100083, China
| | - Shaorong Hao
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
| | - Cong Han
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
| | - Shengjie Gao
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
| | - Shugao Qin
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China; Key Laboratory for Soil and Water Conservation, National Forestry and Grassland Administration, Beijing Forestry University, Beijing 100083, China
| | - Peng Liu
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China; State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing 100083, China; Key Laboratory for Soil and Water Conservation, National Forestry and Grassland Administration, Beijing Forestry University, Beijing 100083, China
| | - Yun Tian
- Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China; State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing 100083, China
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12
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Yan Z, Guo Y, Sun B, Gao Z, Qin P, Li Y, Yue W, Cui H. Combating land degradation through human efforts: Ongoing challenges for sustainable development of global drylands. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 354:120254. [PMID: 38340668 DOI: 10.1016/j.jenvman.2024.120254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 01/19/2024] [Accepted: 01/28/2024] [Indexed: 02/12/2024]
Abstract
Drylands, as highly vulnerable ecosystems, support environmental functions and human well-being. Nevertheless, widespread land degradation and desertification present significant global and regional environmental challenges, with limited consensus on their area and degree. This study used time-series vegetation productivity and meteorological data from 2000 to 2020 to quantify global land degradation trends and driving factors in drylands. The results show a notable restoration of land degradation in drylands worldwide, with the area of improved land exceeding the degraded area by 1.4 times, although the threat of degradation persists. India and China emerge as pioneers in effective land improvement strategies, offering valuable experiences for other regions. Combined effects, as quantitatively distinguished by our established model, dominate the degradation and improvement processes. Notably, human activities play a decisive role in influencing land degradation trends, with the potential for either exacerbation or reversal. This study provides new perspectives on environmental health and human activities from global and regional observations. Finally, our research provides scientific support for desertification control and contributes to the overall advancement of the SDGs globally.
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Affiliation(s)
- Ziyu Yan
- Institute of Forest Resource Information Techniques, Chinese Academy of Forestry, Beijing, 100091, China; Key Laboratory of Forestry Remote Sensing and Information System, NFGA, Beijing, 100091, China
| | - Ye Guo
- Development Research Center of NFGA, Beijing, 100013, China
| | - Bin Sun
- Institute of Forest Resource Information Techniques, Chinese Academy of Forestry, Beijing, 100091, China; Key Laboratory of Forestry Remote Sensing and Information System, NFGA, Beijing, 100091, China.
| | - Zhihai Gao
- Institute of Forest Resource Information Techniques, Chinese Academy of Forestry, Beijing, 100091, China; Key Laboratory of Forestry Remote Sensing and Information System, NFGA, Beijing, 100091, China
| | - Pengyao Qin
- Institute of Forest Resource Information Techniques, Chinese Academy of Forestry, Beijing, 100091, China; Key Laboratory of Forestry Remote Sensing and Information System, NFGA, Beijing, 100091, China
| | - Yifu Li
- Institute of Forest Resource Information Techniques, Chinese Academy of Forestry, Beijing, 100091, China; Key Laboratory of Forestry Remote Sensing and Information System, NFGA, Beijing, 100091, China
| | - Wei Yue
- Institute of Forest Resource Information Techniques, Chinese Academy of Forestry, Beijing, 100091, China; Key Laboratory of Forestry Remote Sensing and Information System, NFGA, Beijing, 100091, China
| | - Hanwen Cui
- Institute of Forest Resource Information Techniques, Chinese Academy of Forestry, Beijing, 100091, China; Key Laboratory of Forestry Remote Sensing and Information System, NFGA, Beijing, 100091, China
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13
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Chen Z, Wang W, Forzieri G, Cescatti A. Transition from positive to negative indirect CO 2 effects on the vegetation carbon uptake. Nat Commun 2024; 15:1500. [PMID: 38374331 PMCID: PMC10876672 DOI: 10.1038/s41467-024-45957-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Accepted: 02/08/2024] [Indexed: 02/21/2024] Open
Abstract
Although elevated atmospheric CO2 concentration (eCO2) has substantial indirect effects on vegetation carbon uptake via associated climate change, their dynamics remain unclear. Here we investigate how the impacts of eCO2-driven climate change on growing-season gross primary production have changed globally during 1982-2014, using satellite observations and Earth system models, and evaluate their evolution until the year 2100. We show that the initial positive effect of eCO2-induced climate change on vegetation carbon uptake has declined recently, shifting to negative in the early 21st century. Such emerging pattern appears prominent in high latitudes and occurs in combination with a decrease of direct CO2 physiological effect, ultimately resulting in a sharp reduction of the current growth benefits induced by climate warming and CO2 fertilization. Such weakening of the indirect CO2 effect can be partially attributed to the widespread land drying, and it is expected to be further exacerbated under global warming.
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Affiliation(s)
- Zefeng Chen
- National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing, China
- Yangtze Institute for Conservation and Development, Hohai University, Nanjing, China
- College of Hydrology and Water Resources, Hohai University, Nanjing, China
| | - Weiguang Wang
- National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing, China.
- Yangtze Institute for Conservation and Development, Hohai University, Nanjing, China.
- College of Hydrology and Water Resources, Hohai University, Nanjing, China.
| | - Giovanni Forzieri
- Department of Civil and Environmental Engineering, University of Florence, Florence, Italy
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14
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Rybchak O, du Toit J, Delorme JP, Jüdt JK, Bieri M, Midgley G, Mukwashi K, Thau C, Feig G, Lucas-Moffat A, Brümmer C. Livestock grazing and biodiversity: Effects on CO 2 exchange in semi-arid Karoo ecosystems, South Africa. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 910:168517. [PMID: 37981131 DOI: 10.1016/j.scitotenv.2023.168517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 11/09/2023] [Accepted: 11/10/2023] [Indexed: 11/21/2023]
Abstract
Livestock use in semi-arid South African ecosystems has not been extensively studied in relation to the Net Ecosystem Exchange (NEE) of carbon dioxide (CO2). We present four years of measurements from twinned eddy-covariance towers in Nama-Karoo, South Africa, to investigate the carbon fluxes and the impact of grazing intensity on NEE. The design contrasted NEE at a long-term site grazed at recommended levels (LG) with a long-term heavily grazed (EG) site that had been rested for 10 years, and was monitored for two years after which intensive grazing was reintroduced for this experiment. This allowed for the quantification of long-term NEE trends on "recovering" vegetations (years I, II) and short-term responses to an intensified land use (years III, IV). The results showed that the net release of CO2 was slightly higher at LG than on "recovering" vegetation at the EG site, where near-neutral exchange was observed during years I and II. However, after grazing was reintroduced to the EG site, differences between sites was reduced but not eliminated. These findings suggest that there is a somewhat higher carbon sequestration potential at the resting EG site than at the LG site, apparently associated with the dominance of unpalatable drought-tolerant grass species and local elimination of many palatable shrubs. Reduction of this sink potential by reintroduction of high-intensity grazing indicates the sensitivity of C-sequestration in this "recovering" system to heavy grazing, but underlines continued resilience of NEE under far heavier grazing than in the LG system. These data suggest notable trade-offs in these ecosystems between carbon storage, biodiversity, and livestock production with rainfall variability being a critical inter-annual driver. PLAIN LANGUAGE SUMMARY: This study suggests that long-term resting of previously over-utilized southern African semi-arid vegetation supports enhanced carbon sequestration potential, even if over-utilization has transformed vegetation composition (i.e. has caused degradation through reduced plant species richness). However, this enhanced carbon sequestration potential can be quickly negated by the reintroduction of grazing, even after 10 years of resting. Achievement of carbon sequestration is dependent on average to above-average precipitation and its distribution throughout the year, with sink activity evident mainly after seasonal rains during the warm season.
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Affiliation(s)
- Oksana Rybchak
- Thünen Institute of Climate-Smart Agriculture, Braunschweig 38116, Germany.
| | - Justin du Toit
- Grootfontein Agricultural Development Institute, Middelburg 5900, South Africa
| | | | - Jens-Kristian Jüdt
- Thünen Institute of Climate-Smart Agriculture, Braunschweig 38116, Germany
| | - Mari Bieri
- Thünen Institute of Climate-Smart Agriculture, Braunschweig 38116, Germany
| | - Guy Midgley
- School for Climate Studies, Stellenbosch University, Stellenbosch 7600, South Africa
| | - Kanisios Mukwashi
- Thünen Institute of Climate-Smart Agriculture, Braunschweig 38116, Germany
| | - Christian Thau
- Department for Earth Observation, Friedrich-Schiller University Jena, Löbdergraben 32, 07743 Jena, Germany
| | - Gregor Feig
- South African Environmental Observation Network, Colbyn, Pretoria 0083, South Africa; Department of Geography, Geoinformatics and Meteorology, University of Pretoria, Pretoria 0002, South Africa
| | - Antje Lucas-Moffat
- Thünen Institute of Climate-Smart Agriculture, Braunschweig 38116, Germany; German Meteorological Service (DWD), Centre for Agrometeorological Research, Bundesallee 33, 38116 Braunschweig, Germany
| | - Christian Brümmer
- Thünen Institute of Climate-Smart Agriculture, Braunschweig 38116, Germany
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15
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Zhang Z, Luo X, Friess DA, Wang S, Li Y, Li Y. Stronger increases but greater variability in global mangrove productivity compared to that of adjacent terrestrial forests. Nat Ecol Evol 2024; 8:239-250. [PMID: 38172286 DOI: 10.1038/s41559-023-02264-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 10/31/2023] [Indexed: 01/05/2024]
Abstract
Mangrove forests are a highly productive ecosystem with important potential to offset anthropogenic greenhouse gas emissions. Mangroves are expected to respond differently to climate change compared to terrestrial forests owing to their location in the tidal environment and unique ecophysiological characteristics, but the magnitude of difference remains uncertain at the global scale. Here we use satellite observations to examine mean trends and interannual variability in the productivity of global mangrove forests and nearby terrestrial evergreen broadleaf forests from 2001 to 2020. Although both types of ecosystem experienced significant recent increases in productivity, mangroves exhibited a stronger increasing trend and greater interannual variability in productivity than evergreen broadleaf forests on three-quarters of their co-occurring coasts. The difference in productivity trends is attributed to the stronger CO2 fertilization effect on mangrove photosynthesis, while the discrepancy in interannual variability is attributed to the higher sensitivities to variations in precipitation and sea level. Our results indicate that mangroves will have a faster increase in productivity than terrestrial forests in a CO2-rich future but may suffer more from deficits in water availability, highlighting a key difference between terrestrial and tidal ecosystems in their responses to climate change.
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Affiliation(s)
- Zhen Zhang
- State Key Laboratory of Marine Environmental Science, Key Laboratory of Coastal and Wetland Ecosystems (Ministry of Education), College of the Environment and Ecology, Xiamen University, Xiamen, China
- Department of Geography, National University of Singapore, Singapore, Singapore
| | - Xiangzhong Luo
- Department of Geography, National University of Singapore, Singapore, Singapore.
- Center for Nature-Based Climate Solutions, National University of Singapore, Singapore, Singapore.
| | - Daniel A Friess
- Department of Earth and Environmental Sciences, Tulane University, New Orleans, LA, USA
| | - Songhan Wang
- Jiangsu Collaborative Innovation Center for Modern Crop Production/Key Laboratory of Crop Physiology and Ecology in Southern China, Nanjing Agricultural University, Nanjing, China
| | - Yi Li
- State Key Laboratory of Marine Environmental Science, Key Laboratory of Coastal and Wetland Ecosystems (Ministry of Education), College of the Environment and Ecology, Xiamen University, Xiamen, China
| | - Yangfan Li
- State Key Laboratory of Marine Environmental Science, Key Laboratory of Coastal and Wetland Ecosystems (Ministry of Education), College of the Environment and Ecology, Xiamen University, Xiamen, China.
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16
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Yu J, Hou G, Shi P, Zong N, Peng J. Nitrogen rather than phosphorous addition alters the asymmetric responses of primary productivity to precipitation variability across a precipitation gradient on the northern Tibetan Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:167856. [PMID: 37866615 DOI: 10.1016/j.scitotenv.2023.167856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 09/25/2023] [Accepted: 10/13/2023] [Indexed: 10/24/2023]
Abstract
Understanding the response of alpine grassland productivity to precipitation fluctuations is essential for assessing the future changes of ecosystem services. However, the underlying mechanism by which grassland productivity responds to wet and dry years after nitrogen (N) or/and phosphorus (P) nutrient addition remains unclear. In this study, we investigated the dynamics of plant communities based on eight-year N or/and P addition gradient experiments in four grassland types across a precipitation gradient on the north Tibetan Plateau. The asymmetry index (AI) was used to evaluate the responses of aboveground net primary productivity (ANPP) to precipitation fluctuations where AI > 0 indicates a greater increase of ANPP in wet years compared to the decline in dry years, and AI < 0 indicates a greater decline of ANPP in dry years compared to the increase in wet years. Our results showed that the AI values at community level in four natural grasslands were non-significant trend across the precipitation gradient, and showed slightly negative asymmetry, suggesting that the increase of ANPP in wet years was less than the decrease in dry years. N addition resulted in a significant decrease in community-level AI values with increasing mean annual precipitation (MAP), indicating that improved nutrient availability may favor the recovery of productivity in drier grasslands in wet years. At the functional group level, nutrient addition resulted in a significant decrease in the AI values of grasses and legumes and an increase in the AI values of forbs as MAP increased. Furthermore, the coupling of nutrients with precipitation can influence the productivity responses to precipitation changes by affecting soil nutrient availability and species richness. This research provides new insights into better predicting vegetation activity on N deposition rates and precipitation changes exacerbated in the context of climate change.
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Affiliation(s)
- Jialuo Yu
- Key Laboratory of Ecosystem Network Observation and Modelling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Ge Hou
- Key Laboratory of Ecosystem Network Observation and Modelling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Peili Shi
- Key Laboratory of Ecosystem Network Observation and Modelling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China.
| | - Ning Zong
- Key Laboratory of Ecosystem Network Observation and Modelling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Jinlong Peng
- Key Laboratory of Ecosystem Network Observation and Modelling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China
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17
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Xia H, Xu X, Xu J, Huang Y, Jiang H, Xu X, Zhang T. Warming, rather than drought, remains the primary factor limiting carbon sequestration. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:167755. [PMID: 37832680 DOI: 10.1016/j.scitotenv.2023.167755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 10/09/2023] [Accepted: 10/10/2023] [Indexed: 10/15/2023]
Abstract
Steppe ecosystems in arid and semiarid regions are particularly sensitive to climate change and strongly regulate the global carbon balance. However, carbon fluxes respond differently to climate change in different growing seasons, and the mechanism of this control is not yet clear. Therefore, we (i) obtained carbon flux data observed by a field eddy station in Inner Mongolia from 2006 to 2021; (ii) investigated the constraint effects of climatic factors on carbon fluxes; (iii) explored the response mechanisms of carbon fluxes to coupled changes in temperature and moisture; (iv) investigated the adaptation of steppe ecosystem to changes in temperature and drought. The results showed that (i) the steppe ecosystem was a carbon sink, with an average annual carbon fixation of 73.55 g C m-2 yr-1 and a roughly N-shaped carbon sink accumulation process within one year. (ii) The constraint effect of temperature and Vapor Pressure Deficit (VPD) on Net Ecosystem Productivity (NEP) and Gross Primary Productivity (GPP) was parabolic, with a clear optimum point. (iii) Temperature and moisture in the soil played a greater role in ecosystem carbon sequestration. Soil Water Content (SWC) could alleviate the inhibitory effect of temperature changes on the carbon sequestration of ecosystem. (iv) This ecosystem was capable of adapting well to changes in temperature and drought. However, warming, rather than drought, remains the primary factor limiting carbon sequestration. Specifically, it was GPP that drives the adaptation of ecosystem carbon sequestration to changes in temperature and drought, rather than Ecosystem Respiration (RECO). Although the steppe ecosystem has a good adaptation to changes in temperature and drought, it is still in the boundary region of warming. We hope that our study will deepen our comprehensive understanding of the relationship between temperature and moisture and ecosystem carbon fluxes and provide evidence for steppe ecosystem adaptation to climate change.
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Affiliation(s)
- Haoyu Xia
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing, China; Faculty of Geographical Science, Beijing Normal University, Beijing, China
| | - Xia Xu
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing, China; Faculty of Geographical Science, Beijing Normal University, Beijing, China.
| | - Jiayu Xu
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing, China; Faculty of Geographical Science, Beijing Normal University, Beijing, China
| | - Yiqin Huang
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing, China; Faculty of Geographical Science, Beijing Normal University, Beijing, China
| | - Honglei Jiang
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Centre of China, School of Marine Sciences, Guangxi University, Nanning, China
| | - Xiaoqing Xu
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing, China; Faculty of Geographical Science, Beijing Normal University, Beijing, China
| | - Tong Zhang
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing, China; Faculty of Geographical Science, Beijing Normal University, Beijing, China
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18
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Tian J, Luo X, Xu H, Green JK, Tang H, Wu J, Piao S. Slower changes in vegetation phenology than precipitation seasonality in the dry tropics. GLOBAL CHANGE BIOLOGY 2024; 30:e17134. [PMID: 38273503 DOI: 10.1111/gcb.17134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 11/21/2023] [Accepted: 12/14/2023] [Indexed: 01/27/2024]
Abstract
The dry tropics occupy ~40% of the tropical land surface and play a dominant role in the trend and interannual variability of the global carbon cycle. Previous studies have reported considerable changes in the dry tropical precipitation seasonality due to climate change, however, the accompanied changes in the length of the vegetation growing season (LGS)-the key period of carbon sequestration-have not been examined. Here, we used long-term satellite observations along with in-situ flux measurements to investigate phenological changes in the dry tropics over the past 40 years. We found that only ~18% of the dry tropics show a significant (p ≤ .1) increasing trend in LGS, while ~13% show a significant decreasing trend. The direction of the LGS change depended not only on the direction of precipitation seasonality change but also on the vegetation water use strategy (i.e. isohydricity) as an adaptation to the long-term average precipitation seasonality (i.e. whether the most of LGS is in the wet season or dry season). Meanwhile, we found that the rate of LGS change was on average ~23% slower than that of precipitation seasonality, caused by a buffering effect from soil moisture. This study uncovers potential mechanisms driving phenological changes in the dry tropics, offering guidance for regional vegetation and carbon cycle studies.
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Affiliation(s)
- Jiaqi Tian
- Department of Geography, National University of Singapore, Singapore
| | - Xiangzhong Luo
- Department of Geography, National University of Singapore, Singapore
- Center for Nature-based Climate Solutions, National University of Singapore, Singapore
| | - Hao Xu
- College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Julia K Green
- Department of Environmental Science, University of Arizona, Tucson, Arizona, USA
| | - Hao Tang
- Department of Geography, National University of Singapore, Singapore
- Center for Nature-based Climate Solutions, National University of Singapore, Singapore
| | - Jin Wu
- School of Biological Sciences and Institute for Climate and Carbon Neutrality, The University of Hong Kong, Hong Kong, China
| | - Shilong Piao
- College of Urban and Environmental Sciences, Peking University, Beijing, China
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19
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Ding L, Li Z, Xu K, Huang M, Shen B, Hou L, Xiao L, Liang S, Shi Z, Wang X, Guo K, Yang Y, Xin X, Chang J. A water stress factor based on normalized difference water index substantially improved the accuracy of light use efficiency model for arid and semi-arid grasslands. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 349:119566. [PMID: 37976647 DOI: 10.1016/j.jenvman.2023.119566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 10/01/2023] [Accepted: 11/04/2023] [Indexed: 11/19/2023]
Abstract
High-accuracy simulation of gross primary productivity (GPP) is crucial for the monitoring and evaluation of the ecosystem services and the adaptive management of grassland. The light use efficiency (LUE) model is one of the most widely-used methods to simulate GPP, given its simple structure and low input requirements. Current LUE models are less applicable to grasslands than other vegetation types and have lower overall estimation accuracy in arid and semi-arid regions. A grassland-specific light use efficiency model (GRASS-LUE), which optimizes three important parameters (the fraction of absorbed photosynthetically active radiation FPAR, optimum temperature Topt and water stress factor f(W)), has been developed to improve the accuracy of GPP simulation for grasslands along aridity gradients. GPP simulated by the GRASS-LUE agreed well with the eddy covariance (EC) GPP estimates for grasslands along the aridity gradient at 8-day (coefficient of determination (R2) = 0.85, Bias = -0.67 gC m-2 day-1), monthly (R2 = 0.88, Bias = -22.33 gC m-2 month-1) and annual time scales (R2 = 0.95, Bias = -118.91 gC m-2 year-1). Compared with five state-of-the-art GPP products (PML, MOD17, rEC-LUE, VPM and BESS), GRASS-LUE had the best and most stable performance in reproducing EC GPP, especially for semi-arid grassland, with the highest global performance indicator (GPI) value. Sensitivity tests further revealed that: 1) modifying f(W) to be based on the Normalized Difference Water Index (NDWI) substantially improved the model accuracy for arid and semi-arid grasslands and 2) using the minimum of temperature and water stress factors (i.e., min(f(W),f(T))) to represent environmental stress in GRASS-LUE was better than that from the multiplication of temperature and water stress factors (i.e., f(W)×f(T)).
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Affiliation(s)
- Lei Ding
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China; State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Zhenwang Li
- Jiangsu Key Laboratory of Crop Genetics and Physiology/ Jiangsu Key Laboratory of Crop Cultivation and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Kang Xu
- School of Environmental Engineering, Wuxi University, Jiangsu, 214105, China
| | - Mengtian Huang
- Chinese Academy of Meteorological Science, Beijing, 100081, China
| | - Beibei Shen
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Lulu Hou
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Liujun Xiao
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China
| | - Shefang Liang
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Zhou Shi
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Xu Wang
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Kaiwen Guo
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Yuanyuan Yang
- The School of Spatial Planning & Design of Hangzhou City University, Hangzhou, 310015, China
| | - Xiaoping Xin
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Jinfeng Chang
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
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20
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Hajek OL, Knapp AK. Signatures of autumn deluges revealed during spring drought in a semi-arid grassland. Oecologia 2024; 204:83-93. [PMID: 38108892 DOI: 10.1007/s00442-023-05488-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 11/08/2023] [Indexed: 12/19/2023]
Abstract
Increases in extremely large precipitation events (deluges) and shifts in seasonal patterns of water availability with climate change will both have important consequences for ecosystem function, particularly in water-limited regions. While previous work in the semi-arid shortgrass steppe of northeastern Colorado has demonstrated this ecosystem's strong sensitivity to growing season deluges, our understanding of ecosystem responses to deluges during the dormant season is limited. Here, we imposed experimental 100 mm deluges (~ 30% of mean annual precipitation) in either September or October in a native C4-dominated shortgrass steppe ecosystem to evaluate the impact of this post-growing season shift in water availability during the autumn and the following growing season. Soil moisture for both deluge treatments remained elevated compared with ambient levels through April as spring precipitation was atypically low. Despite overall low levels of productivity with spring drought, these deluges from the previous autumn increased aboveground net primary production (ANPP), primarily due to increases with C4 grasses. C3 ANPP was also enhanced, largely due to an increase in the annual C3 grass, Vulpia octoflora, in the October deluge treatment. While spring precipitation has historically been the primary determinant of ecosystem function in this ecosystem, this combination of two climate extremes-an extremely wet autumn followed by a naturally-occurring spring drought-revealed the potential for meaningful carryover effects from autumn precipitation. With climate change increasing the likelihood of extremes during all seasons, experiments which create novel climatic conditions can provide new insight into the dynamics of ecosystem functioning in the future.
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Affiliation(s)
- Olivia L Hajek
- Graduate Degree Program in Ecology and Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA.
| | - Alan K Knapp
- Graduate Degree Program in Ecology and Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA
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21
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Li X, Ramos Aguila LC, Wu D, Lie Z, Xu W, Tang X, Liu J. Carbon sequestration and storage capacity of Chinese fir at different stand ages. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166962. [PMID: 37696397 DOI: 10.1016/j.scitotenv.2023.166962] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 08/27/2023] [Accepted: 09/08/2023] [Indexed: 09/13/2023]
Abstract
In southern China, Chinese fir Cunninghamia lanceolata is one of the most important native conifer trees, widely used in afforestation programs. This area has the largest forestland atmospheric carbon sink, and a relatively young stand age characterizes these forests. However, how C. lanceolata forests evolved regarding their ability to sequester carbon remains unclear. Here we present data on carbon storage and sequestration capacity of C. lanceolata at six stand ages (5-, 10-, 15-, 20-, 30- and 60 - year-old stands). Results show that the carbon stock in trees, understory, vegetation, litter, soil, and ecosystem significantly increased with forest age. The total ecosystem carbon stock increased from 129.11 to 348.43 Mg ha-1 in the 5- and 60 - year-old stands. The carbon sequestration rate of C. lanceolata shows an overall increase in the first two stand intervals (5-10 and 10-15), peaks in the 15-20 stand intervals, and then decreases in the 20-30 and 30-60 stand intervals. Our result revealed that carbon sequestration rate is a matter of tree age, with the highest sequestration rates occurring in the middle age forest (15-20 - year-old). Therefore, this information may be useful for national climate change mitigation actions and afforestation programs, since forests are primarily planted for this purpose.
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Affiliation(s)
- Xu Li
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Luis Carlos Ramos Aguila
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Donghai Wu
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Zhiyang Lie
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Wenfang Xu
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Xuli Tang
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Juxiu Liu
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
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22
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Guasconi D, Manzoni S, Hugelius G. Climate-dependent responses of root and shoot biomass to drought duration and intensity in grasslands-a meta-analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166209. [PMID: 37572920 DOI: 10.1016/j.scitotenv.2023.166209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 08/08/2023] [Accepted: 08/08/2023] [Indexed: 08/14/2023]
Abstract
Understanding the effects of altered precipitation regimes on root biomass in grasslands is crucial for predicting grassland responses to climate change. Nonetheless, studies investigating the effects of drought on belowground vegetation have produced mixed results. In particular, root biomass under reduced precipitation may increase, decrease or show a delayed response compared to shoot biomass, highlighting a knowledge gap in the relationship between belowground net primary production and drought. To address this gap, we conducted a meta-analysis of nearly 100 field observations of grassland root and shoot biomass changes under experimental rainfall reduction to disentangle the main drivers behind grassland responses to drought. Using a response-ratio approach we tested the hypothesis that water scarcity would induce a decrease in total biomass, but an increase in belowground biomass allocation with increased drought length and intensity, and that climate (as defined by the aridity index of the study location) would be an additional predictor. As expected, meteorological drought decreased root and shoot biomass, but aboveground and belowground biomass exhibited contrasting responses to drought duration and intensity, and their interaction with climate. In particular, drought duration had negative effects on root biomass only in wet climates while more intense drought had negative effects on root biomass only in dry climates. Shoot biomass responded negatively to drought duration regardless of climate. These results show that long-term climate is an important modulator of belowground vegetation responses to drought, which might be a consequence of different drought tolerance and adaptation strategies. This variability in vegetation responses to drought suggests that physiological plasticity and community composition shifts may mediate how climate affects carbon allocation in grasslands, and thus ultimately carbon storage in soil.
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Affiliation(s)
- Daniela Guasconi
- Department of Physical Geography, Stockholm University, Stockholm, Sweden; Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden.
| | - Stefano Manzoni
- Department of Physical Geography, Stockholm University, Stockholm, Sweden; Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden
| | - Gustaf Hugelius
- Department of Physical Geography, Stockholm University, Stockholm, Sweden; Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden
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23
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Zhang Y, Li C, Chiew FHS, Post DA, Zhang X, Ma N, Tian J, Kong D, Leung LR, Yu Q, Shi J, Liu C. Southern Hemisphere dominates recent decline in global water availability. Science 2023; 382:579-584. [PMID: 37917705 DOI: 10.1126/science.adh0716] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 09/11/2023] [Indexed: 11/04/2023]
Abstract
Global land water underpins livelihoods, socioeconomic development, and ecosystems. It remains unclear how water availability has changed in recent decades. Using an ensemble of observations, we quantified global land water availability over the past two decades. We show that the Southern Hemisphere has dominated the declining trend in global water availability from 2001 to 2020. The significant decrease occurs mainly in South America, southwestern Africa, and northwestern Australia. In the Northern Hemisphere, the complex regional increasing and decreasing trends cancel each other, resulting in a negligible hemispheric trend. The variability and trend in water availability in the Southern Hemisphere are largely driven by precipitation associated with climate modes, particularly the El Niño-Southern Oscillation. This study highlights their dominant role in controlling global water availability.
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Affiliation(s)
- Yongqiang Zhang
- Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Congcong Li
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, China
- CSIRO Environment, Black Mountain, Canberra, ACT 2601, Australia
| | | | - David A Post
- CSIRO Environment, Black Mountain, Canberra, ACT 2601, Australia
| | - Xuanze Zhang
- Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Ning Ma
- Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Jing Tian
- Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Dongdong Kong
- Department of Atmospheric Science, School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - L Ruby Leung
- Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Qiang Yu
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, China
| | - Jiancheng Shi
- National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
| | - Changming Liu
- Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
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24
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Li H, Terrer C, Berdugo M, Maestre FT, Zhu Z, Peñuelas J, Yu K, Luo L, Gong JY, Ye JS. Nitrogen addition delays the emergence of an aridity-induced threshold for plant biomass. Natl Sci Rev 2023; 10:nwad242. [PMID: 37900195 PMCID: PMC10600907 DOI: 10.1093/nsr/nwad242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 09/05/2023] [Accepted: 09/11/2023] [Indexed: 10/31/2023] Open
Abstract
Crossing certain aridity thresholds in global drylands can lead to abrupt decays of ecosystem attributes such as plant productivity, potentially causing land degradation and desertification. It is largely unknown, however, whether these thresholds can be altered by other key global change drivers known to affect the water-use efficiency and productivity of vegetation, such as elevated CO2 and nitrogen (N). Using >5000 empirical measurements of plant biomass, we showed that crossing an aridity (1-precipitation/potential evapotranspiration) threshold of ∼0.50, which marks the transition from dry sub-humid to semi-arid climates, led to abrupt declines in aboveground biomass (AGB) and progressive increases in root:shoot ratios, thus importantly affecting carbon stocks and their distribution. N addition significantly increased AGB and delayed the emergence of its aridity threshold from 0.49 to 0.55 (P < 0.05). By coupling remote sensing estimates of leaf area index with simulations from multiple models, we found that CO2 enrichment did not alter the observed aridity threshold. By 2100, and under the RCP 8.5 scenario, we forecast a 0.3% net increase in the global land area exceeding the aridity threshold detected under a scenario that includes N deposition, in comparison to a 2.9% net increase if the N effect is not considered. Our study thus indicates that N addition could mitigate to a great extent the negative impact of increasing aridity on plant biomass in drylands. These findings are critical for improving forecasts of abrupt vegetation changes in response to ongoing global environmental change.
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Affiliation(s)
- Hailing Li
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou730000, China
| | - César Terrer
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Miguel Berdugo
- Instituto Multidisciplinar para el Estudio del Medio “Ramón Margalef,” Universidad de Alicante, Alicante 03690, Spain
- Institut de Biologia Evolutiva (CSIC-UPF), Barcelona08003, Spain
| | - Fernando T Maestre
- Instituto Multidisciplinar para el Estudio del Medio “Ramón Margalef,” Universidad de Alicante, Alicante 03690, Spain
- Departamento de Ecología, Universidad de Alicante, Alicante 03690, Spain
| | - Zaichun Zhu
- School of Urban Planning and Design, Peking University Shenzhen Graduate School, Peking University, Shenzhen518055, China
| | - Josep Peñuelas
- CSIC, Global Ecology Unit CREAF-CSIC-UAB, Barcelona 08193, Spain
- CREAF, Cerdanyola del Vallès, Barcelona 08193, Spain
| | - Kailiang Yu
- High Meadows Environmental Institute, Princeton University, Princeton, NJ 08544, USA
| | - Lin Luo
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou730000, China
| | - Jie-Yu Gong
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou730000, China
| | - Jian-Sheng Ye
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou730000, China
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25
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Gupta S, Deb Burman PK, Tiwari YK, Dumka UC, Kumari N, Srivastava A, Raghubanshi AS. Understanding carbon sequestration trends using model and satellite data under different ecosystems in India. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 897:166381. [PMID: 37595902 DOI: 10.1016/j.scitotenv.2023.166381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 08/13/2023] [Accepted: 08/15/2023] [Indexed: 08/20/2023]
Abstract
This study discusses carbon sequestration variability in different ecosystems of India. Four different biosphere regions, each over 0.5° × 0.5° area, have been selected considering the geospatial and climatic variability of these regions expanding from Central India (CI), the Northeast region (NER), the Western Ghats (WG), and the Western Himalayan region (WHNI). The climatic conditions of these four regions are different so are the biosphere constituents of these regions. We expect the Gross Primary Productivity (GPP) to enhance during the all India summer monsoon rainfall season but in varied magnitudes suggesting a role of climatic parameters and flora in these regions. The GPP from FLUXCOM for the duration of 2001 to 2019 (19 years) and satellite-derived vegetation indices like the Normalized Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), and Leaf Area Index (LAI) are used in this study to understand the response of regional vegetation to this variability. EVI seems to be better related to GPP in comparison to NDVI in the preliminary analysis. Further analysis suggests LAI correlates better to GPP than EVI and NDVI in different seasons in these four regions. Also, meteorological parameters like surface temperature, rainfall, soil water, and other derived parameters like Vapor Pressure Deficit (VPD) are studied. It is also observed that the year-to-year variability in the climatic conditions could also have a role to play in the observed features. It is proven that the climate around the world is experiencing changes. Vegetation is one of the potent markers to monitor the impact of climate change. These long-term data and trends were studied to understand if there is any significant impact of the changing climatic conditions on the vegetation in these regions. Our study shows that there is an increasing (positive) trend in GPP at these locations though at different rates. WG and WHNI have shown a significant high rate of increase (6.44 and 5.36 gCm-2 y-1, respectively) in GPP over the last two decades.
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Affiliation(s)
- Smrati Gupta
- Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune, India; Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi, India
| | - Pramit Kumar Deb Burman
- Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune, India; Department of Atmospheric and Space Sciences, Savitribai Phule Pune University, Pune, India
| | - Yogesh K Tiwari
- Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune, India; Department of Atmospheric and Space Sciences, Savitribai Phule Pune University, Pune, India.
| | | | - Nikul Kumari
- Faculty of Science, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Ankur Srivastava
- Faculty of Science, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Akhilesh S Raghubanshi
- Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi, India
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26
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Giardina F, Gentine P, Konings AG, Seneviratne SI, Stocker BD. Diagnosing evapotranspiration responses to water deficit across biomes using deep learning. THE NEW PHYTOLOGIST 2023; 240:968-983. [PMID: 37621238 DOI: 10.1111/nph.19197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 07/23/2023] [Indexed: 08/26/2023]
Abstract
Accounting for water limitation is key to determining vegetation sensitivity to drought. Quantifying water limitation effects on evapotranspiration (ET) is challenged by the heterogeneity of vegetation types, climate zones and vertically along the rooting zone. Here, we train deep neural networks using flux measurements to study ET responses to progressing drought conditions. We determine a water stress factor (fET) that isolates ET reductions from effects of atmospheric aridity and other covarying drivers. We regress fET against the cumulative water deficit, which reveals the control of whole-column moisture availability. We find a variety of ET responses to water stress. Responses range from rapid declines of fET to 10% of its water-unlimited rate at several savannah and grassland sites, to mild fET reductions in most forests, despite substantial water deficits. Most sensitive responses are found at the most arid and warm sites. A combination of regulation of stomatal and hydraulic conductance and access to belowground water reservoirs, whether in groundwater or deep soil moisture, could explain the different behaviors observed across sites. This variety of responses is not captured by a standard land surface model, likely reflecting simplifications in its representation of belowground water storage.
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Affiliation(s)
- Francesco Giardina
- Institute of Agricultural Sciences, Department of Environmental Systems Science, ETH Zürich, Zürich, CH-8092, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
- Center for Learning the Earth with Artificial Intelligence and Physics (LEAP), Columbia University, New York, NY, 10027, USA
| | - Alexandra G Konings
- Department of Earth System Science, Stanford University, Stanford, CA, 94305, USA
| | - Sonia I Seneviratne
- Institute for Atmospheric and Climate Science, Department of Environmental Systems Science, ETH Zurich, Zürich, CH-8092, Switzerland
| | - Benjamin D Stocker
- Institute of Agricultural Sciences, Department of Environmental Systems Science, ETH Zürich, Zürich, CH-8092, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, CH-8903, Switzerland
- Institute of Geography, University of Bern, Hallerstrasse 12, Bern, 3012, Switzerland
- Oeschger Centre for Climate Change Research, University of Bern, Falkenplatz 16, Bern, 3012, Switzerland
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27
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McNicol IM, Keane A, Burgess ND, Bowers SJ, Mitchard ETA, Ryan CM. Protected areas reduce deforestation and degradation and enhance woody growth across African woodlands. COMMUNICATIONS EARTH & ENVIRONMENT 2023; 4:392. [PMID: 38665189 PMCID: PMC11041809 DOI: 10.1038/s43247-023-01053-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 10/13/2023] [Indexed: 04/28/2024]
Abstract
Protected areas are increasingly promoted for their capacity to sequester carbon, alongside biodiversity benefits. However, we have limited understanding of whether they are effective at reducing deforestation and degradation, or promoting vegetation growth, and the impact that this has on changes to aboveground woody carbon stocks. Here we present a new satellite radar-based map of vegetation carbon change across southern Africa's woodlands and combine this with a matching approach to assess the effect of protected areas on carbon dynamics. We show that protection has a positive effect on aboveground carbon, with stocks increasing faster in protected areas (+0.53% per year) compared to comparable lands not under protection (+0.08% per year). The positive effect of protection reflects lower rates of deforestation (-39%) and degradation (-25%), as well as a greater prevalence of vegetation growth (+12%) inside protected lands. Areas under strict protection had similar outcomes to other types of protection after controlling for differences in location, with effect scores instead varying more by country, and the level of threat. These results highlight the potential for protected areas to sequester aboveground carbon, although we caution that in some areas this may have negative impacts on biodiversity, and human wellbeing.
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Affiliation(s)
- Iain M. McNicol
- School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3FF UK
| | - Aidan Keane
- School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3FF UK
| | - Neil D. Burgess
- United Nations Environment Programme – World Conservation Monitoring Centre (UNEP-WCMC), Cambridge, CB3 0DL UK
- Centre for Macroecology, Evolution and Climate, Natural History Museum, University of Copenhagen, Copenhagen, Denmark
| | - Samuel J. Bowers
- School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3FF UK
| | | | - Casey M. Ryan
- School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3FF UK
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28
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Li X, Ryu Y, Xiao J, Dechant B, Liu J, Li B, Jeong S, Gentine P. New-generation geostationary satellite reveals widespread midday depression in dryland photosynthesis during 2020 western U.S. heatwave. SCIENCE ADVANCES 2023; 9:eadi0775. [PMID: 37531429 PMCID: PMC10396307 DOI: 10.1126/sciadv.adi0775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Accepted: 06/29/2023] [Indexed: 08/04/2023]
Abstract
Emerging new-generation geostationary satellites have broadened the scope for studying the diurnal cycle of ecosystem functions. We exploit observations from the Geostationary Operational Environmental Satellite-R series to examine the effect of a severe U.S. heatwave in 2020 on the diurnal variations of ecosystem photosynthesis. We find divergent responses of photosynthesis to the heatwave across vegetation types and aridity gradients, with drylands exhibiting widespread midday and afternoon depression in photosynthesis. The diurnal centroid and peak time of dryland gross primary production (GPP) substantially shift toward earlier morning times, reflecting notable water and heat stress. Our geostationary satellite-based method outperforms traditional radiation-based upscaling methods from polar-orbiting satellite snapshots in estimating daily GPP and GPP loss during heatwaves. These findings underscore the potential of geostationary satellites for diurnal photosynthesis monitoring and highlight the necessity to consider the increased diurnal asymmetry in GPP under stress when evaluating carbon-climate interactions.
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Affiliation(s)
- Xing Li
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
| | - Youngryel Ryu
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
- Department of Landscape Architecture and Rural Systems Engineering, College of Agriculture and Life Sciences, Seoul National University, South Korea
| | - Jingfeng Xiao
- Earth Systems Research Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH, USA
| | - Benjamin Dechant
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
- Leipzig University, Leipzig, Germany
| | - Jiangong Liu
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
| | - Bolun Li
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
| | - Sungchan Jeong
- Department of Landscape Architecture and Rural Systems Engineering, College of Agriculture and Life Sciences, Seoul National University, South Korea
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
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29
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Nathaniel J, Liu J, Gentine P. MetaFlux: Meta-learning global carbon fluxes from sparse spatiotemporal observations. Sci Data 2023; 10:440. [PMID: 37433802 DOI: 10.1038/s41597-023-02349-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 06/29/2023] [Indexed: 07/13/2023] Open
Abstract
We provide a global, long-term carbon flux dataset of gross primary production and ecosystem respiration generated using meta-learning, called MetaFlux. The idea behind meta-learning stems from the need to learn efficiently given sparse data by learning how to learn broad features across tasks to better infer other poorly sampled ones. Using meta-trained ensemble of deep models, we generate global carbon products on daily and monthly timescales at a 0.25-degree spatial resolution from 2001 to 2021, through a combination of reanalysis and remote-sensing products. Site-level validation finds that MetaFlux ensembles have lower validation error by 5-7% compared to their non-meta-trained counterparts. In addition, they are more robust to extreme observations, with 4-24% lower errors. We also checked for seasonality, interannual variability, and correlation to solar-induced fluorescence of the upscaled product and found that MetaFlux outperformed other machine-learning based carbon product, especially in the tropics and semi-arids by 10-40%. Overall, MetaFlux can be used to study a wide range of biogeochemical processes.
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Affiliation(s)
- Juan Nathaniel
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA.
| | - Jiangong Liu
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
| | - Pierre Gentine
- Department of Earth and Environmental Engineering, Columbia University, New York, NY, 10027, USA
- Climate School, Columbia University, New York, NY, 10027, USA
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Brown RF, Collins SL. As above, not so below: Long-term dynamics of net primary production across a dryland transition zone. GLOBAL CHANGE BIOLOGY 2023; 29:3941-3953. [PMID: 37095743 DOI: 10.1111/gcb.16744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 03/26/2023] [Indexed: 05/03/2023]
Abstract
Drylands are key contributors to interannual variation in the terrestrial carbon sink, which has been attributed primarily to broad-scale climatic anomalies that disproportionately affect net primary production (NPP) in these ecosystems. Current knowledge around the patterns and controls of NPP is based largely on measurements of aboveground net primary production (ANPP), particularly in the context of altered precipitation regimes. Limited evidence suggests belowground net primary production (BNPP), a major input to the terrestrial carbon pool, may respond differently than ANPP to precipitation, as well as other drivers of environmental change, such as nitrogen deposition and fire. Yet long-term measurements of BNPP are rare, contributing to uncertainty in carbon cycle assessments. Here, we used 16 years of annual NPP measurements to investigate responses of ANPP and BNPP to several environmental change drivers across a grassland-shrubland transition zone in the northern Chihuahuan Desert. ANPP was positively correlated with annual precipitation across this landscape; however, this relationship was weaker within sites. BNPP, on the other hand, was weakly correlated with precipitation only in Chihuahuan Desert shrubland. Although NPP generally exhibited similar trends among sites, temporal correlations between ANPP and BNPP within sites were weak. We found chronic nitrogen enrichment stimulated ANPP, whereas a one-time prescribed burn reduced ANPP for nearly a decade. Surprisingly, BNPP was largely unaffected by these factors. Together, our results suggest that BNPP is driven by a different set of controls than ANPP. Furthermore, our findings imply belowground production cannot be inferred from aboveground measurements in dryland ecosystems. Improving understanding around the patterns and controls of dryland NPP at interannual to decadal scales is fundamentally important because of their measurable impact on the global carbon cycle. This study underscores the need for more long-term measurements of BNPP to improve assessments of the terrestrial carbon sink, particularly in the context of ongoing environmental change.
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Affiliation(s)
- Renée F Brown
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Scott L Collins
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
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31
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Barros-Rodríguez A, García-Gálvez C, Pacheco P, Kalyuzhnaya MG, Manzanera M. Isolation of Methane Enriched Bacterial Communities and Application as Wheat Biofertilizer under Drought Conditions: An Environmental Contribution. PLANTS (BASEL, SWITZERLAND) 2023; 12:2487. [PMID: 37447048 DOI: 10.3390/plants12132487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/23/2023] [Accepted: 06/27/2023] [Indexed: 07/15/2023]
Abstract
The search for methanotrophs as plant-growth-promoting rhizobacteria (PGPR) presents an important contribution to mitigating the impact of global warming by restoring the natural soil potential for consuming methane while benefiting plants during droughts. Our in silico simulations suggest that water, produced as a byproduct of methane oxidation, can satisfy the cell growth requirement. In addition to water, methanotrophs can produce metabolites that stimulate plant growth. Considering this, we proposed that applying methanotrophs as PGPR can alleviate the effect of droughts on crops, while stimulating atmospheric methane consumption. In this work, we isolated a series of methanotrophic communities from the rhizospheres of different crops, including Italian sweet pepper and zucchini, using an atmosphere enriched with pure methane gas, to determine their potential for alleviating drought stress in wheat plants. Subsequently, 23 strains of nonmethanotrophic bacteria present in the methanotrophic communities were isolated and characterized. We then analyzed the contribution of the methane-consuming consortia to the improvement of plant growth under drought conditions, showing that some communities contributed to increases in the wheat plants' lengths and weights, with statistically significant differences according to ANOVA models. Furthermore, we found that the presence of methane gas can further stimulate the plant-microbe interactions, resulting in larger plants and higher drought tolerance.
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Affiliation(s)
- Adoración Barros-Rodríguez
- Institute for Water Research and Department of Microbiology, University of Granada, 18071 Granada, Spain
- VitaNtech Biotechnology S.L., 18008 Granada, Spain
| | - Carlos García-Gálvez
- Institute for Water Research and Department of Microbiology, University of Granada, 18071 Granada, Spain
- VitaNtech Biotechnology S.L., 18008 Granada, Spain
| | - Pamela Pacheco
- Institute for Water Research and Department of Microbiology, University of Granada, 18071 Granada, Spain
| | | | - Maximino Manzanera
- Institute for Water Research and Department of Microbiology, University of Granada, 18071 Granada, Spain
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32
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Martinez L, Wu S, Baur L, Patton MT, Owen-Smith P, Collins SL, Rudgers JA. Soil nematode assemblages respond to interacting environmental changes. Oecologia 2023:10.1007/s00442-023-05412-y. [PMID: 37368022 DOI: 10.1007/s00442-023-05412-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 06/15/2023] [Indexed: 06/28/2023]
Abstract
Multi-factor experiments suggest that interactions among environmental changes commonly influence biodiversity and community composition. However, most field experiments manipulate only single factors. Soil food webs are critical to ecosystem health and may be particularly sensitive to interactions among environmental changes that include soil warming, eutrophication, and altered precipitation. Here, we asked how environmental changes interacted to alter soil nematode communities in a northern Chihuahuan Desert grassland. Factorial manipulations of nitrogen, winter rainfall, and nighttime warming matched predictions for regional environmental change. Warming reduced nematode diversity by 25% and genus-level richness by 32%, but declines dissipated with additional winter rain, suggesting that warming effects occurred via drying. Interactions between precipitation and nitrogen also altered nematode community composition, but only weakly affected total nematode abundance, indicating that most change involved reordering of species abundances. Specifically, under ambient precipitation, nitrogen fertilizer reduced bacterivores by 68% and herbivores by 73%, but did not affect fungivores. In contrast, under winter rain addition, nitrogen fertilization increased bacterivores by 95%, did not affect herbivores, and doubled fungivore abundance. Rain can reduce soil nitrogen availability and increase turnover in the microbial loop, potentially promoting the recovery of nematode populations overwhelmed by nitrogen eutrophication. Nematode communities were not tightly coupled to plant community composition and may instead track microbes, including biocrusts or decomposers. Our results highlight the importance of interactions among environmental change stressors for shaping the composition and function of soil food webs in drylands.
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Affiliation(s)
- Laura Martinez
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Shuqi Wu
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA.
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China.
| | - Lauren Baur
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Mariah T Patton
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Paul Owen-Smith
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Scott L Collins
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Jennifer A Rudgers
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA
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Sun Y, Wen J, Gu L, Joiner J, Chang CY, van der Tol C, Porcar-Castell A, Magney T, Wang L, Hu L, Rascher U, Zarco-Tejada P, Barrett CB, Lai J, Han J, Luo Z. From remotely-sensed solar-induced chlorophyll fluorescence to ecosystem structure, function, and service: Part II-Harnessing data. GLOBAL CHANGE BIOLOGY 2023; 29:2893-2925. [PMID: 36802124 DOI: 10.1111/gcb.16646] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 02/09/2023] [Accepted: 02/14/2023] [Indexed: 05/03/2023]
Abstract
Although our observing capabilities of solar-induced chlorophyll fluorescence (SIF) have been growing rapidly, the quality and consistency of SIF datasets are still in an active stage of research and development. As a result, there are considerable inconsistencies among diverse SIF datasets at all scales and the widespread applications of them have led to contradictory findings. The present review is the second of the two companion reviews, and data oriented. It aims to (1) synthesize the variety, scale, and uncertainty of existing SIF datasets, (2) synthesize the diverse applications in the sector of ecology, agriculture, hydrology, climate, and socioeconomics, and (3) clarify how such data inconsistency superimposed with the theoretical complexities laid out in (Sun et al., 2023) may impact process interpretation of various applications and contribute to inconsistent findings. We emphasize that accurate interpretation of the functional relationships between SIF and other ecological indicators is contingent upon complete understanding of SIF data quality and uncertainty. Biases and uncertainties in SIF observations can significantly confound interpretation of their relationships and how such relationships respond to environmental variations. Built upon our syntheses, we summarize existing gaps and uncertainties in current SIF observations. Further, we offer our perspectives on innovations needed to help improve informing ecosystem structure, function, and service under climate change, including enhancing in-situ SIF observing capability especially in "data desert" regions, improving cross-instrument data standardization and network coordination, and advancing applications by fully harnessing theory and data.
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Affiliation(s)
- Ying Sun
- School of Integrative Plant Science, Soil and Crop Sciences Section, Cornell University, Ithaca, New York, USA
| | - Jiaming Wen
- School of Integrative Plant Science, Soil and Crop Sciences Section, Cornell University, Ithaca, New York, USA
| | - Lianhong Gu
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Joanna Joiner
- National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC), Greenbelt, Maryland, USA
| | - Christine Y Chang
- US Department of Agriculture, Agricultural Research Service, Adaptive Cropping Systems Laboratory, Beltsville, Maryland, USA
| | - Christiaan van der Tol
- Affiliation Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Enschede, The Netherlands
| | - Albert Porcar-Castell
- Optics of Photosynthesis Laboratory, Institute for Atmospheric and Earth System Research (INAR)/Forest Sciences, Viikki Plant Science Center (ViPS), University of Helsinki, Helsinki, Finland
| | - Troy Magney
- Department of Plant Sciences, University of California, Davis, Davis, California, USA
| | - Lixin Wang
- Department of Earth Sciences, Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis, Indiana, USA
| | - Leiqiu Hu
- Department of Atmospheric and Earth Science, University of Alabama in Huntsville, Huntsville, Alabama, USA
| | - Uwe Rascher
- Institute of Bio- and Geosciences, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Pablo Zarco-Tejada
- School of Agriculture and Food (SAF-FVAS) and Faculty of Engineering and Information Technology (IE-FEIT), University of Melbourne, Melbourne, Victoria, Australia
| | - Christopher B Barrett
- Charles H. Dyson School of Applied Economics and Management, Cornell University, Ithaca, New York, USA
| | - Jiameng Lai
- School of Integrative Plant Science, Soil and Crop Sciences Section, Cornell University, Ithaca, New York, USA
| | - Jimei Han
- School of Integrative Plant Science, Soil and Crop Sciences Section, Cornell University, Ithaca, New York, USA
| | - Zhenqi Luo
- School of Integrative Plant Science, Soil and Crop Sciences Section, Cornell University, Ithaca, New York, USA
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Wang X, Li Y, Wang L, Duan Y, Yao B, Chen Y, Cao W. Soil extracellular enzyme stoichiometry reflects microbial metabolic limitations in different desert types of northwestern China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 874:162504. [PMID: 36863586 DOI: 10.1016/j.scitotenv.2023.162504] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 02/22/2023] [Accepted: 02/23/2023] [Indexed: 06/18/2023]
Abstract
Soil extracellular enzyme activity (EEA) stoichiometry reflects the dynamic balance between microorganism metabolic demands for resources and nutrient availability. However, variations in metabolic limitations and their driving factors in arid desert areas with oligotrophic environments remain poorly understood. In this study, we investigated sites in different desert types in western China and measured the activities of two C-acquiring enzymes (β-1,4-glucosidase and β-D-cellobiohydrolase), two N-acquiring enzymes (β-1,4-N-acetylglucosaminidase and L-leucine aminopeptidase), and one organic-P-acquiring enzyme (alkaline phosphatase) to quantify and compare the metabolic limitations of soil microorganisms based on their EEA stoichiometry. The ratios of log-transformed C-, N-, and P-acquiring enzyme activities for all deserts combined were 1:1.1:0.9, which is close to the hypothetical global mean EEA stoichiometry (1:1:1). We quantified the microbial nutrient limitation by means of vector analysis using the proportional EEAs, and found that microbial metabolism was co-limited by soil C and N. For different desert types, the microbial N limitation increased in the following order: gravel desert < sand desert < mud desert < salt desert. Overall, the study area's climate explained the largest proportion of the variation in the microbial limitation (17.9 %), followed by soil abiotic factors (6.6 %) and biological factors (5.1 %). Our results confirmed that the EEA stoichiometry method can be used in microbial resource ecology research in a range of desert types, and that the soil microorganisms maintained community-level nutrient element homeostasis by adjusting enzyme production to increase uptake of scarce nutrients even in extremely oligotrophic environments such as deserts.
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Affiliation(s)
- Xuyang Wang
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China; Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Tongliao 028300, China
| | - Yuqiang Li
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China; Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Tongliao 028300, China.
| | - Lilong Wang
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China; Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Tongliao 028300, China
| | - Yulong Duan
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China; Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Tongliao 028300, China
| | - Bo Yao
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China; Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Tongliao 028300, China
| | - Yun Chen
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China; Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Tongliao 028300, China
| | - Wenjie Cao
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China; Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Tongliao 028300, China
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35
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Wang X, Ji M, Zhang Y, Zhang L, Akram MA, Dong L, Hu W, Xiong J, Sun Y, Li H, Degen AA, Ran J, Deng J. Plant trait networks reveal adaptation strategies in the drylands of China. BMC PLANT BIOLOGY 2023; 23:266. [PMID: 37202776 DOI: 10.1186/s12870-023-04273-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 05/08/2023] [Indexed: 05/20/2023]
Abstract
BACKGROUND Plants accomplish multiple functions by the interrelationships between functional traits. Clarifying the complex relationships between plant traits would enable us to better understand how plants employ different strategies to adapt to the environment. Although increasing attention is being paid to plant traits, few studies focused on the adaptation to aridity through the relationship among multiple traits. We established plant trait networks (PTNs) to explore the interdependence of sixteen plant traits across drylands. RESULTS Our results revealed significant differences in PTNs among different plant life-forms and different levels of aridity. Trait relationships for woody plants were weaker, but were more modularized than for herbs. Woody plants were more connected in economic traits, whereas herbs were more connected in structural traits to reduce damage caused by drought. Furthermore, the correlations between traits were tighter with higher edge density in semi-arid than in arid regions, suggesting that resource sharing and trait coordination are more advantageous under low drought conditions. Importantly, our results demonstrated that stem phosphorus concentration (SPC) was a hub trait correlated with other traits across drylands. CONCLUSIONS The results demonstrate that plants exhibited adaptations to the arid environment by adjusting trait modules through alternative strategies. PTNs provide a new insight into understanding the adaptation strategies of plants to drought stress based on the interdependence among plant functional traits.
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Affiliation(s)
- Xiaoting Wang
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou, 730000, China
| | - Mingfei Ji
- Collaborative Innovation Center of Water Security for Water Source Region of Mid-Route Project of South-North Water Diversion of Henan Province, College of Water Resource and Environment Engineering, Nanyang Normal University, Nanyang, 473061, China
| | - Yahui Zhang
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou, 730000, China
| | - Liang Zhang
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou, 730000, China
| | - Muhammad Adnan Akram
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou, 730000, China
- School of Economics, Lanzhou University, Lanzhou, 730000, China
| | - Longwei Dong
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou, 730000, China
| | - Weigang Hu
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou, 730000, China
| | - Junlan Xiong
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou, 730000, China
| | - Ying Sun
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou, 730000, China
| | - Hailin Li
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou, 730000, China
| | - Abraham Allan Degen
- Desert Animal Adaptations and Husbandry, Wyler Department of Dryland Agriculture, Blaustein Institutes for Desert Research, Ben-Gurion University of Negev, Beer Sheva, 8410500, Israel
| | - Jinzhi Ran
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou, 730000, China
| | - Jianming Deng
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou, 730000, China.
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Zhang J, Zhang Y, Cong N, Tian L, Zhao G, Zheng Z, Gao J, Zhu Y, Zhang Y. Coarse spatial resolution remote sensing data with AVHRR and MODIS miss the greening area compared with the Landsat data in Chinese drylands. FRONTIERS IN PLANT SCIENCE 2023; 14:1129665. [PMID: 37265636 PMCID: PMC10230077 DOI: 10.3389/fpls.2023.1129665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 04/10/2023] [Indexed: 06/03/2023]
Abstract
The warming-wetting climates in Chinese drylands, together with a series of ecological engineering projects, had caused apparent changes to vegetation therein. Regarding the vegetation greening trend, different remote sensing data had yielded distinct findings. It was critical to evaluate vegetation dynamics in Chinese drylands using a series of remote sensing data. By comparing the three most commonly used remote sensing datasets [i.e., MODIS, Advanced Very High Resolution Radiometer (AVHRR), and Landsat], this study comprehensively investigated vegetation dynamics for Chinse drylands. All three remote sensing datasets exhibited evident vegetation greening trends from 2000 to 2020 in Chinese drylands, especially in the Loess Plateau and Northeast China. However, Landsat identified the largest greening areas (89.8%), while AVHRR identified the smallest greening area (58%). The vegetation greening areas identified by Landsat comprise more small patches than those identified by MODIS and AVHRR. The MODIS data exhibited a higher consistency with Landsat than with AVHRR in terms of detecting vegetation greening areas. The three datasets exhibited high consistency in identifying vegetation greening in Northeast China, Loess Plateau, and Xinjiang. The percentage of inconsistent areas among the three datasets was 39.56%. The vegetation greening areas identified by Landsat comprised more small patches. Sensors and the atmospheric effect are the two main reasons responsible for the different outputs from each NDVI product. Ecological engineering projects had a great promotion effect on vegetation greening, which can be detected by the three NDVI datasets in Chinese drylands, thereby combating desertification and reducing dust storms.
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Affiliation(s)
- Jianshuang Zhang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Yangjian Zhang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, China
| | - Nan Cong
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Li Tian
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Guang Zhao
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Zhoutao Zheng
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Jie Gao
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yixuan Zhu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yu Zhang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
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Jin Y, Tian D, Li J, Wu Q, Pan Z, Han M, Wang Y, Zhang J, Han G. Water causes divergent responses of specific carbon sink to long-term grazing in a desert grassland. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 873:162166. [PMID: 36801405 DOI: 10.1016/j.scitotenv.2023.162166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 02/06/2023] [Accepted: 02/07/2023] [Indexed: 06/18/2023]
Abstract
Heavy grazing generally reduces grassland biomass, further decreasing its carbon sink. Grassland carbon sink is determined by both plant biomass and carbon sink per unit biomass (specific carbon sink). This specific carbon sink could reflect grassland adaptative response, because plants generally tend to adaptively enhance the functioning of their remaining biomass after grazing (i.e. higher leaf nitrogen content). Though we know well about the regulation of grassland biomass on carbon sink, little attention is paid to the role of specific carbon sink. Thus, we conducted a 14-year grazing experiment in a desert grassland. Ecosystem carbon fluxes, including net ecosystem CO2 exchange (NEE), gross ecosystem productivity (GEP) and ecosystem respiration (ER), were measured frequently during five consecutive growing seasons with contrasting precipitation events. We found that heavy grazing reduced NEE more in drier (-94.0 %) than wetter (-33.9 %) years. However, grazing did not reduce community biomass much more in drier (-70.4 %) than wetter years (-66.0 %). These meant a positive response of specific NEE (NEE per unit biomass) to grazing in wetter years. This positive response of specific NEE was mainly caused by a higher biomass ratio of other species versus perennial grasses with greater leaf nitrogen content and specific leaf area in wetter years. In addition, we also detected a shift of grazing effects on specific NEE from positive in wetter years to negative in drier years. Overall, this study is among the first to reveal the adaptive response of grassland specific carbon sink to experimental grazing in plant trait view. The stimulation response of specific carbon sink can partially compensate for the loss of grassland carbon storage under grazing. These new findings highlight the role of grassland adaptive response in decelerating climate warming.
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Affiliation(s)
- Yuxi Jin
- Key Laboratory of Grassland Resources of the Ministry of Education, Key Laboratory of Forage Cultivation, Processing and High Efficient Utilization of the Ministry of Agriculture and Rural Affairs, Inner Mongolia Key Laboratory of Grassland Management and Utilization, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot 010011, China
| | - Dashuan Tian
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China.
| | - Jiangwen Li
- College of Life Sciences, Yan' an University, Yan' an 716000, China
| | - Qian Wu
- Key Laboratory of Grassland Resources of the Ministry of Education, Key Laboratory of Forage Cultivation, Processing and High Efficient Utilization of the Ministry of Agriculture and Rural Affairs, Inner Mongolia Key Laboratory of Grassland Management and Utilization, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot 010011, China
| | - Zhanlei Pan
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Mengqi Han
- Key Laboratory of Grassland Resources of the Ministry of Education, Key Laboratory of Forage Cultivation, Processing and High Efficient Utilization of the Ministry of Agriculture and Rural Affairs, Inner Mongolia Key Laboratory of Grassland Management and Utilization, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot 010011, China
| | - Yuehua Wang
- Key Laboratory of Grassland Resources of the Ministry of Education, Key Laboratory of Forage Cultivation, Processing and High Efficient Utilization of the Ministry of Agriculture and Rural Affairs, Inner Mongolia Key Laboratory of Grassland Management and Utilization, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot 010011, China
| | - Jun Zhang
- College of Science, Inner Mongolia Agricultural University, Hohhot 010011, China
| | - Guodong Han
- Key Laboratory of Grassland Resources of the Ministry of Education, Key Laboratory of Forage Cultivation, Processing and High Efficient Utilization of the Ministry of Agriculture and Rural Affairs, Inner Mongolia Key Laboratory of Grassland Management and Utilization, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot 010011, China.
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38
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Xu X, Wu B, Bao F, Gao Y, Li X, Cao Y, Lu Q, Gao J, Xin Z, Liu M. Different Responses of Growing Season Ecosystem CO 2 Fluxes to Rain Addition in a Desert Ecosystem. PLANTS (BASEL, SWITZERLAND) 2023; 12:1158. [PMID: 36904018 PMCID: PMC10005604 DOI: 10.3390/plants12051158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 02/21/2023] [Accepted: 02/22/2023] [Indexed: 06/18/2023]
Abstract
Desert ecosystem CO2 exchange may play an important role in global carbon cycling. However, it is still not clear how the CO2 fluxes of shrub-dominated desert ecosystems respond to precipitation changes. We performed a 10-year long-term rain addition experiment in a Nitraria tangutorum desert ecosystem in northwestern China. In the growing seasons of 2016 and 2017, with three rain addition treatments (natural precipitation +0%, +50%, and +100% of annual average precipitation), gross ecosystem photosynthesis (GEP), ecosystem respiration (ER), and net ecosystem CO2 exchange (NEE) were measured. The GEP responded nonlinearly and the ER linearly to rain addition. The NEE presented a nonlinear response along the rain addition gradient, with a saturation threshold by rain addition between +50% and +100%. The growing season mean NEE ranged from -2.25 to -5.38 μmol CO2 m-2 s-1, showing net CO2 uptake effect, with significant enhancement (more negative) under the rain addition treatments. Although natural rainfall fluctuated greatly in the growing seasons of 2016 and 2017, reaching 134.8% and 44.0% of the historical average, the NEE values remained stable. Our findings highlight that growing season CO2 sequestration in desert ecosystems will increase against the background of increasing precipitation levels. The different responses of GEP and ER of desert ecosystems under changing precipitation regimes should be considered in global change models.
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Affiliation(s)
- Xiaotian Xu
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China
- Institute of Forestry and Pomology, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100093, China
| | - Bo Wu
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China
- Key Laboratory of Desert Ecosystem and Global Change, State Administration of Forestry and Grassland, Beijing 100091, China
| | - Fang Bao
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China
- Key Laboratory of Desert Ecosystem and Global Change, State Administration of Forestry and Grassland, Beijing 100091, China
| | - Ying Gao
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China
- Key Laboratory of Desert Ecosystem and Global Change, State Administration of Forestry and Grassland, Beijing 100091, China
| | - Xinle Li
- The Experimental Center of Desert Forestry of the Chinese Academy of Forestry, Bayannur 015200, China
- Dengkou Desert Ecosystem Research Station of Inner Mongolia, Bayannur 015200, China
| | - Yanli Cao
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China
- Key Laboratory of Desert Ecosystem and Global Change, State Administration of Forestry and Grassland, Beijing 100091, China
| | - Qi Lu
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China
- Key Laboratory of Desert Ecosystem and Global Change, State Administration of Forestry and Grassland, Beijing 100091, China
| | - Junliang Gao
- The Experimental Center of Desert Forestry of the Chinese Academy of Forestry, Bayannur 015200, China
- Dengkou Desert Ecosystem Research Station of Inner Mongolia, Bayannur 015200, China
| | - Zhiming Xin
- The Experimental Center of Desert Forestry of the Chinese Academy of Forestry, Bayannur 015200, China
- Dengkou Desert Ecosystem Research Station of Inner Mongolia, Bayannur 015200, China
| | - Minghu Liu
- The Experimental Center of Desert Forestry of the Chinese Academy of Forestry, Bayannur 015200, China
- Dengkou Desert Ecosystem Research Station of Inner Mongolia, Bayannur 015200, China
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Bayala J, van Noordwijk M. Carbon stocks of billions of individual African dryland trees estimated. Nature 2023; 615:35-36. [PMID: 36859586 DOI: 10.1038/d41586-023-00531-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
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Recent decrease of the impact of tropical temperature on the carbon cycle linked to increased precipitation. Nat Commun 2023; 14:965. [PMID: 36810352 PMCID: PMC9944254 DOI: 10.1038/s41467-023-36727-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 02/15/2023] [Indexed: 02/24/2023] Open
Abstract
The atmospheric CO2 growth rate (CGR) variability is largely controlled by tropical temperature fluctuations. The sensitivity of CGR to tropical temperature [Formula: see text] has strongly increased since 1960, but here we show that this trend has ceased. Here, we use the long-term CO2 records from Mauna Loa and the South Pole to compute CGR, and show that [Formula: see text] increased by 200% from 1960-1979 to 1979-2000 but then decreased by 117% from 1980-2001 to 2001-2020, almost returning back to the level of the 1960s. Variations in [Formula: see text] are significantly correlated with changes in precipitation at a bi-decadal scale. These findings are further corroborated by results from a dynamic vegetation model, collectively suggesting that increases in precipitation control the decreased [Formula: see text] during recent decades. Our results indicate that wetter conditions have led to a decoupling of the impact of the tropical temperature variation on the carbon cycle.
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Zhang Q, Chen Y, Li Z, Sun C, Xiang Y, Liu Z. Spatio-Temporal Development of Vegetation Carbon Sinks and Sources in the Arid Region of Northwest China. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:3608. [PMID: 36834302 PMCID: PMC9966209 DOI: 10.3390/ijerph20043608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/14/2023] [Accepted: 02/15/2023] [Indexed: 06/18/2023]
Abstract
Drylands, which account for 41% of Earth's land surface and are home to more than two billion people, play an important role in the global carbon balance. This study analyzes the spatio-temporal patterns of vegetation carbon sinks and sources in the arid region of northwest China (NWC), using the net ecosystem production (NEP) through the Carnegie-Ames-Stanford approach (CASA). It quantitatively evaluates regional ecological security over a 20-year period (2000-2020) via a remote sensing ecological index (RSEI) and other ecological indexes, such as the Normalized Difference Vegetation Index (NDVI), fraction of vegetation cover (FVC), net primary productivity (NPP), and land use. The results show that the annual average carbon capacity of vegetation in NWC changed from carbon sources to carbon sinks, and the vegetation NEP increased at a rate of 1.98 gC m-2 yr-1 from 2000 to 2020. Spatially, the annual NEP in northern Xinjiang (NXJ), southern Xinjiang (SXJ) and Hexi Corridor (HX) increased at even faster rates of 2.11, 2.22, and 1.98 gC m-2 yr-1, respectively. Obvious geographically heterogeneous distributions and changes occurred in vegetation carbon sinks and carbon sources. Some 65.78% of the vegetation areas in NWC were carbon sources during 2000-2020, which were concentrated in the plains, and SXJ, the majority carbon sink areas are located in the mountains. The vegetation NEP in the plains exhibited a positive trend (1.21 gC m-2 yr-1) during 2000-2020, but this speed has slowed since 2010. The vegetation NEP in the mountain exhibited only intermittent changes (2.55 gC m-2 yr-1) during 2000-2020; it exhibited a negative trend during 2000-2010, but this trend has reversed strongly since 2010. The entire ecological security of NWC was enhanced during the study period. Specifically, the RSEI increased from 0.34 to 0.49, the NDVI increased by 0.03 (17.65%), the FVC expanded by 19.56%, and the NPP increased by 27.44%. Recent positive trends in NDVI, FVC and NPP have enhanced the capacity of vegetation carbon sinks, and improved the eco-environment of NWC. The scientific outcomes of this study are of great importance for maintaining ecological stability and sustainable economic development along China's Silk Road Economic Belt.
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Affiliation(s)
- Qifei Zhang
- School of Geographical Sciences, Shanxi Normal University, Taiyuan 030031, China
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Research Center of Ecology and Environment in the Middle Reaches of the Yellow River, Shanxi Normal University, Taiyuan 030031, China
| | - Yaning Chen
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
| | - Zhi Li
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
| | - Congjian Sun
- School of Geographical Sciences, Shanxi Normal University, Taiyuan 030031, China
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Research Center of Ecology and Environment in the Middle Reaches of the Yellow River, Shanxi Normal University, Taiyuan 030031, China
| | - Yanyun Xiang
- School of Public Administration, Shanxi University of Finance and Economics, Taiyuan 030006, China
| | - Zhihui Liu
- School of Geographical Sciences, Shanxi Normal University, Taiyuan 030031, China
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Yuan Z, Tong S, Bao G, Chen J, Yin S, Li F, Sa C, Bao Y. Spatiotemporal variation of autumn phenology responses to preseason drought and temperature in alpine and temperate grasslands in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 859:160373. [PMID: 36414072 DOI: 10.1016/j.scitotenv.2022.160373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 11/16/2022] [Accepted: 11/17/2022] [Indexed: 06/16/2023]
Abstract
We investigate the spatiotemporal patterns and environmental controls of the end of the vegetation growing season (EOS) in autumn across the alpine and temperate grasslands of China from 2001 through 2020, focusing on whether the EOS is likely a "dryness effect" due to drought or a "coolness effect" caused by cold temperature in autumn. The results show that the EOS date is earlier (∼6 days earlier on average) in alpine grasslands than in temperate grasslands. During 2001-2020, a slight non-significant delay of 1.0 day/decade is observed for the regional averaged EOS, which is mostly induced by the delayed EOS in 64.4 % of the study region. Preseason temperature (1-2 months before the EOS) exerts a positive control on the EOS in most of the alpine grasslands and some regions of the eastern part of the temperate grasslands, while drought with a mean length of 3.2 months before the EOS exerts positive effects on the EOS in the central, southwestern, and western parts of the temperate grasslands and in the northeastern part of the alpine grasslands. The positive effects of temperature and drought are very likely phenomena reflecting that the EOS is the "coolness effect" associated with lower temperatures in autumn and the "dryness effect" due to drought, especially meteorological drought without consideration of soil moisture, in late summer and/or early autumn, respectively. Our findings are supported by an analysis of the spatial patterns of the cold degree days (CDD) and EOS sensitivity to the CDD. However, the negative effects of drought are also found in eastern temperate grasslands, likely caused by decreased temperature accompanied by increased moisture. The results presented here highlight the importance of incorporating the impacts of droughts on EOS variability, as well as their interactive effects with temperature, into current vegetation autumn phenology models for grasslands.
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Affiliation(s)
- Zhihui Yuan
- College of Geographical Science, Inner Mongolia Normal University, Hohhot 010022, China; Inner Mongolia Key Laboratory of Remote Sensing and Geographic Information Systems, Inner Mongolia Normal University, Hohhot 010022, China; Department of Natural Resources, Wulanchabu 012000, China
| | - Siqin Tong
- College of Geographical Science, Inner Mongolia Normal University, Hohhot 010022, China
| | - Gang Bao
- College of Geographical Science, Inner Mongolia Normal University, Hohhot 010022, China; Inner Mongolia Key Laboratory of Remote Sensing and Geographic Information Systems, Inner Mongolia Normal University, Hohhot 010022, China.
| | - Jiquan Chen
- Department of Geography, Environment, and Spatial Sciences, Michigan State University, East Lansing, MI 48823, USA
| | - Shan Yin
- College of Geographical Science, Inner Mongolia Normal University, Hohhot 010022, China
| | - Fei Li
- Grassland Research Institute, Chinese Academy of Agricultural Sciences, Hohhot 010010, China
| | - Chula Sa
- College of Geographical Science, Inner Mongolia Normal University, Hohhot 010022, China
| | - Yuhai Bao
- College of Geographical Science, Inner Mongolia Normal University, Hohhot 010022, China; Inner Mongolia Key Laboratory of Remote Sensing and Geographic Information Systems, Inner Mongolia Normal University, Hohhot 010022, China
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43
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Liu Z, Chen Z, Yu G, Zhang W, Zhang T, Han L. The role of climate, vegetation, and soil factors on carbon fluxes in Chinese drylands. FRONTIERS IN PLANT SCIENCE 2023; 14:1060066. [PMID: 36844101 PMCID: PMC9947249 DOI: 10.3389/fpls.2023.1060066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Accepted: 01/02/2023] [Indexed: 06/18/2023]
Abstract
Drylands dominate the trend and variability of the land carbon (C) sink. A better understanding of the implications of climate-induced changes in the drylands for C sink-source dynamics is urgently needed. The effect of climate on ecosystem C fluxes (gross primary productivity (GPP), ecosystem respiration (ER), and net ecosystem productivity (NEP)) in drylands has been extensively explored, but the roles of other concurrently changing factors, such as vegetation conditions and nutrient availability, remain unclear. We used eddy-covariance C-flux measurements from 45 ecosystems with concurrent information on climate (mean annual temperature (MAT) and mean annual precipitation (MAP)), soil (soil moisture (SM) and soil total nitrogen content (soil N)), and vegetation (leaf area index (LAI) and leaf nitrogen content (LNC)) factors to assess their roles in C fluxes. The results showed that the drylands in China were weak C sinks. GPP and ER were positively correlated with MAP, while they were negatively correlated with MAT. NEP first decreased and then increased with increasing MAT and MAP, and 6.6 °C and 207 mm were the boundaries for the NEP response to MAT and MAP, respectively. SM, soil N, LAI, and MAP were the main factors affecting GPP and ER. However, SM and LNC had the most important influence on NEP. Compared with climate and vegetation factors, soil factors (SM and soil N) had a greater impact on C fluxes in the drylands. Climate factors mainly affected C fluxes by regulating vegetation and soil factors. To accurately estimate the global C balance and predict the response of ecosystems to environmental change, it is necessary to fully consider the discrepant effects of climate, vegetation, and soil factors on C fluxes, as well as the cascade relationships between different factors.
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Affiliation(s)
- Zhaogang Liu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Zhi Chen
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
- Yanshan Earth Critical Zone and Surface Fluxes Research Station, University of Chinese Academy of Sciences, Beijing, China
| | - Guirui Yu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
- Yanshan Earth Critical Zone and Surface Fluxes Research Station, University of Chinese Academy of Sciences, Beijing, China
| | - Weikang Zhang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Tianyou Zhang
- College of Grassland Agriculture, Northwest A&F University, Yangling, China
| | - Lang Han
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, China
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He L, Guo J, Yang W, Jiang Q, Chen L, Tang K. Multifaceted responses of vegetation to average and extreme climate change over global drylands. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159942. [PMID: 36343828 DOI: 10.1016/j.scitotenv.2022.159942] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 10/25/2022] [Accepted: 10/31/2022] [Indexed: 06/16/2023]
Abstract
Average climatic events describe the occurrence of weather or climate at an average value, whereas extreme events are defined as events that exceed the upper or lower threshold value of statistical or observational average climatic events. This study investigated the impacts of both average climate change (ACC) (i.e., average precipitation, temperature, and potential evapotranspiration [PET]) and extreme climate change (ECC) (i.e., five precipitation and five temperature extremes) on dryland vegetation based on the Normalized Difference Vegetation Index (NDVI). The spatial divergences of ACC and ECC in affecting changes in NDVI over drylands were determined using the geographical detector model. In this study, the growth of vegetation in 40.29 % of global drylands was driven by average precipitation and this dominant effect also occurred in all the plant species, particularly shrubs. However, the sensitivity of grassland to average precipitation exceeded that of most of the woody vegetation. The average temperature and PET controlled 28.64 % and 31.07 % of the changes in NDVI, respectively. Precipitation extremes (except for consecutive dry days and consecutive wet days) and warm temperature extremes (WTE) had positive influences on dryland vegetation, and the effect of WTE on NDVI exceeded that of the remaining temperature extremes. Temperature extremes exerted more significant effects than precipitation extremes for changes in the grassland NDVI. In contrast, the variations in shrub NDVI were primarily dominated by precipitation extremes. We also found that the impacts of parts of average and extreme climatic factors on vegetation had changed over time. Furthermore, temperature extremes had far exceeded the average temperature in affecting vegetation growth at the spatial scale, and this action gradually intensified from 1982 to 2015. The influences of all precipitation extremes were weaker than those of the average precipitation. Those can offer scientific references for ecosystem protection in drylands.
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Affiliation(s)
- Liang He
- Key Laboratory of State Forestry Administration on Soil and Water Conservation, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
| | - Jianbin Guo
- Key Laboratory of State Forestry Administration on Soil and Water Conservation, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China.
| | - Wenbin Yang
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China
| | - Qunou Jiang
- Key Laboratory of State Forestry Administration on Soil and Water Conservation, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
| | - Lin Chen
- Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China, College of Ecology and Environmental Science, Ningxia University, Yinchuan, Ningxia 750021, China
| | - Kexin Tang
- Key Laboratory of State Forestry Administration on Soil and Water Conservation, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
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Flores-Rentería D, Delgado-Balbuena J, Campuzano EF, Curiel Yuste J. Seasonal controlling factors of CO 2 exchange in a semiarid shrubland in the Chihuahuan Desert, Mexico. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159918. [PMID: 36368389 DOI: 10.1016/j.scitotenv.2022.159918] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 10/17/2022] [Accepted: 10/29/2022] [Indexed: 06/16/2023]
Abstract
The still significant uncertainties associated with the future capacity of terrestrial systems to mitigate climate change are linked to the lack of knowledge of the biotic and abiotic processes that regulate CO2 net ecosystem exchange (NEE) in space/time. Mainly, rates and controls of CO2 exchange from arid ecosystems, despite dominating the global trends in interannual variability of the terrestrial CO2 sink capacity, are probably the most poorly understood of all. We present a study on rates and controls of CO2 exchange measured with the eddy covariance (EC) technique in the Chihuahuan Desert in the Northeast of Mexico, to understand how the environmental controls of the NEE switch throughout the year using a multilevel approach. Since this is a water-limited ecosystem, the hydroecological year, based on the last precipitation and the decay of air temperature, was used to compare the wet (from May 16 to October 30, 2019) and dry (November 1, 2019 to May 15, 2020) seasons' controlling mechanisms, both at diurnal and nocturnal times. Annual NEE was -303.5 g C m-2, with a cumulative Reco of 537.7 g C m-2 and GPP of 841.3 g C m-2. NEE showed radiation, temperature, and soil moisture sensitivity along the day, however, shifts in these controls along the year and between seasons were identified. The winter precipitations during the dry season led to fast C release followed by lagged C uptake. Despite this flux pulse, the ecosystem was a net sink throughout most of the year because the local vegetation is well adapted to grow and uptake C under these arid conditions, even during the dry season. Understanding the controls of the sink-source shifts is relevant since the predictions for future climate include changes in the precipitation patterns.
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Affiliation(s)
- Dulce Flores-Rentería
- CONACYT-CINVESTAV Unidad Saltillo, Grupo de Sustentabilidad de los Recursos Naturales y Energía, Av. Industria Metalúrgica 1062, Parque Industrial Ramos Arizpe, C.P. 25900 Ramos Arizpe, Coahuila, Mexico.
| | - Josue Delgado-Balbuena
- Instituto de Investigaciones Forestales, Agrícolas y Pecuarias, CENID Agricultura Familiar, Mexico
| | - Emmanuel F Campuzano
- CINVESTAV Unidad Saltillo, Grupo de Sustentabilidad de los Recursos Naturales y Energía, Av. Industria Metalúrgica 1062, Parque Industrial Ramos Arizpe, C.P. 25900 Ramos Arizpe, Coahuila, Mexico; UTV Unidad Académica Capulhuac, Calle s/n, 611 Oriente de, México, Lomas de San Juan, C.P. 52700 Capulhuac de Mirafuentes, Estado de México, Mexico
| | - Jorge Curiel Yuste
- BC3 - Basque Centre for Climate Change, Scientific Campus of the University of the Basque Country, 48940 Leioa, Spain; IKERBASQUE - Basque Foundation for Science, Maria Diaz de Haro 3, 6 solairua, 48013 Bilbao, Bizkaia, Spain
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46
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Wang S, Fu B, Wei F, Piao S, Maestre FT, Wang L, Jiao W, Liu Y, Li Y, Li C, Zhao W. Drylands contribute disproportionately to observed global productivity increases. Sci Bull (Beijing) 2023; 68:224-232. [PMID: 36681590 DOI: 10.1016/j.scib.2023.01.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 10/22/2022] [Accepted: 10/24/2022] [Indexed: 01/15/2023]
Abstract
Drylands cover about 40% of the terrestrial surface and are sensitive to climate change, but their relative contributions to global vegetation greening and productivity increase in recent decades are still poorly known. Here, by integrating satellite data and biosphere modeling, we showed that drylands contributed more to global gross primary productivity (GPP) increase (65% ± 16%) than to Earth greening (33% ± 15%) observed during 1982-2015. The enhanced productivity per unit leaf area, i.e., light-use efficiency (LUE), was the mechanism behind this pattern. We also found that LUE was more sensitive to soil moisture than to atmospheric vapor pressure deficit (VPD) in drylands, while the opposite was observed (i.e., LUE was more sensitive to VPD) in humid areas. Our findings suggest the importance of using different moisture stress metrics in projecting the vegetation productivity changes of dry versus humid regions and highlight the prominent role of drylands as key controllers of the global carbon cycle.
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Affiliation(s)
- Shuai Wang
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
| | - Bojie Fu
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China; State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Fangli Wei
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shilong Piao
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Fernando T Maestre
- Department of Ecology, University of Alicante, Carretera de San Vicente del Raspeig, Alicante 03690, Spain; Multidisciplinary Institute for Environment Studies "Ramon Margalef", University of Alicante, Carretera de San Vicente del Raspeig, Alicante 03690, Spain
| | - Lixin Wang
- Department of Earth Sciences, Indiana University-Purdue University Indianapolis, Indianapolis IN 46202, USA
| | - Wenzhe Jiao
- Department of Earth Sciences, Indiana University-Purdue University Indianapolis, Indianapolis IN 46202, USA
| | - Yanxu Liu
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
| | - Yan Li
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
| | - Changjia Li
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
| | - Wenwu Zhao
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
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Fang Q, Lu A, Hong H, Kuzyakov Y, Algeo TJ, Zhao L, Olshansky Y, Moravec B, Barrientes DM, Chorover J. Mineral weathering is linked to microbial priming in the critical zone. Nat Commun 2023; 14:345. [PMID: 36670099 PMCID: PMC9860040 DOI: 10.1038/s41467-022-35671-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 12/16/2022] [Indexed: 01/21/2023] Open
Abstract
Decomposition of soil organic matter (SOM) can be stimulated by fresh organic matter input, a phenomenon known as the 'priming effect'. Despite its global importance, the relationship of the priming effect to mineral weathering and nutrient release remains unclear. Here we show close linkages between mineral weathering in the critical zone and primed decomposition of SOM. Intensified mineral weathering and rock-derived nutrient release are generally coupled with primed SOM decomposition resulting from "triggered" microbial activity. Fluxes of organic matter products decomposed via priming are linearly correlated with weathering congruency. Weathering congruency influences the formation of organo-mineral associations, thereby modulating the accessibility of organic matter to microbial decomposers and, thus, the priming effect. Our study links weathering with primed SOM decomposition, which plays a key role in controlling soil C dynamics in space and time. These connections represent fundamental links between long-term lithogenic element cycling (= weathering) and rapid turnover of carbon and nutrients (= priming) in soil.
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Affiliation(s)
- Qian Fang
- School of Earth and Space Sciences, Peking University, 100871, Beijing, China
- Department of Environmental Science, University of Arizona, Tucson, AZ, 85721-0038, USA
- State Key Laboratory of Biogeology and Environmental Geology, School of Earth Sciences, China University of Geosciences, 430074, Wuhan, China
| | - Anhuai Lu
- School of Earth and Space Sciences, Peking University, 100871, Beijing, China.
| | - Hanlie Hong
- State Key Laboratory of Biogeology and Environmental Geology, School of Earth Sciences, China University of Geosciences, 430074, Wuhan, China
| | - Yakov Kuzyakov
- Department of Soil Sciences of Temperate Ecosystems, Department of Agricultural Soil Sciences, University of Göttingen, 37077, Göttingen, Germany
- Peoples Friendship University of Russia (RUDN University), Moscow, Russia
| | - Thomas J Algeo
- State Key Laboratory of Biogeology and Environmental Geology, School of Earth Sciences, China University of Geosciences, 430074, Wuhan, China
- Department of Geosciences, University of Cincinnati, Cincinnati, OH, 45221-0013, USA
- State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, 430074, Wuhan, China
| | - Lulu Zhao
- State Key Laboratory of Biogeology and Environmental Geology, School of Earth Sciences, China University of Geosciences, 430074, Wuhan, China
| | - Yaniv Olshansky
- Department of Environmental Science, University of Arizona, Tucson, AZ, 85721-0038, USA
- Department of Crop, Soil and Environmental Sciences, Auburn University, Auburn, AL, 36849, USA
| | - Bryan Moravec
- Department of Environmental Science, University of Arizona, Tucson, AZ, 85721-0038, USA
| | - Danielle M Barrientes
- Department of Environmental Science, University of Arizona, Tucson, AZ, 85721-0038, USA
| | - Jon Chorover
- Department of Environmental Science, University of Arizona, Tucson, AZ, 85721-0038, USA.
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48
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Kumar S, Sharma LK. Assessment of water and carbon use efficiency in the SAARC region for ecological resilience under changing climate. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 326:116812. [PMID: 36435123 DOI: 10.1016/j.jenvman.2022.116812] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 10/10/2022] [Accepted: 11/14/2022] [Indexed: 06/16/2023]
Abstract
According to the United Nations International Children's Emergency Fund (UNICEF) assessment report released in 2021, South Asian countries were among the most vulnerable in the world to the effects of climate change on future generations. Hence it is become crucial to assess how resilient the ecosystems are to these changes. The current study incorporated a novel approach, the Combined Ecological Resiliency Indices Approach (CERIA), to assess ecological resiliency status at various scales during hydroclimatic disturbances. Water and carbon use efficiency (WUE and CUE, respectively) were used as indicators for the examination of ecological resilience. The standardized Precipitation Index (SPI) was adopted to assess the initial stage of hydroclimatic disturbances (meteorological drought). A resiliency analysis based on combined Rd and Rd' indices (derived from WUE and CUE, respectively) revealed that just 1.87% land cover area of the entire SAARC (South Asian Association for Regional Cooperation) region's total 17 land cover classes was resilient to meteorological drought. At the river basin scale, only 16.58% of the total 62 river basins were found resilient. Only 11 (27.46%) of the 21 climate classes on the Koppen climate classification scale were resilient to the hydro-climatic disturbance period. To achieve the United Nations sustainable development goals (SDGs goal-2 and goal-13) of 'No Hunger' and 'Protect the Planet', the Joint Ecosystem Resiliency Enhancement Programme (JEREP) should be adopted in land cover, river basins, or climatic classes of the SAARC region that were highly affected.
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Affiliation(s)
- Shubham Kumar
- Environmental Remote Sensing Lab, Department of Environmental Science, School of Earth Sciences, Central University of Rajasthan, Bandarsindri, 305817, Ajmer, India
| | - Laxmi Kant Sharma
- Environmental Remote Sensing Lab, Department of Environmental Science, School of Earth Sciences, Central University of Rajasthan, Bandarsindri, 305817, Ajmer, India.
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49
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Chang Q, He H, Ren X, Zhang L, Feng L, Lv Y, Zhang M, Xu Q, Liu W, Zhang Y, Wang T. Soil moisture drives the spatiotemporal patterns of asymmetry in vegetation productivity responses across China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 855:158819. [PMID: 36116661 DOI: 10.1016/j.scitotenv.2022.158819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 09/12/2022] [Accepted: 09/13/2022] [Indexed: 06/15/2023]
Abstract
Increasingly drastic global change is expected to cause hydroclimatic changes, which will influence vegetation productivity and pose a threat to the terrestrial carbon sink. Asymmetry represents an imbalance between vegetation growth and loss of growth during dry and wet periods, respectively. However, the mechanisms of asymmetric plant responses to hydrological changes remain poorly understood. Here, we examined the spatiotemporal patterns of asymmetric responses of vegetation productivity across terrestrial ecosystems in China. We analyzed several observational and satellite-based datasets of plant productivity and several reanalyzed datasets of hydroclimatic variables from 2001 to 2020, and used a random forest model to assess the importance of hydroclimatic variables for these responses. Our results showed that the productivity of >50 % of China's vegetated areas showed a more positive asymmetry (2.3 ± 9.4 %) over the study period, which were distributed broadly in northwest China (mainly grasslands and sparse vegetation ecosystems). Negative asymmetries were most common in forest ecosystems in northeast China. We demonstrated that one-third of vegetated areas tended to exhibit significant changes in asymmetry during 2001-2020. The trend towards stronger positive asymmetry (0.95 % yr-1) was higher than that towards stronger negative asymmetry (-0.55 % yr-1), which is beneficial for the carbon sink. We further showed that in China, soil moisture was a more important driver of spatiotemporal changes in asymmetric productivity than precipitation. We identified thresholds of surface soil moisture (20-30 %, volume water content) and root-zone soil moisture (200-350 mm, equivalent water height) that were associated with changes in asymmetry. Our findings highlight the necessity of considering the dynamic responses of vegetation to hydrological factors in order to fully understand the physiological growth processes of plants and avoid the possible loss of productivity due to future climate change.
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Affiliation(s)
- Qingqing Chang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; National Ecological Science Data Center, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Honglin He
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; National Ecological Science Data Center, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Xiaoli Ren
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; National Ecological Science Data Center, Beijing 100101, China
| | - Li Zhang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; National Ecological Science Data Center, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lili Feng
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; National Ecological Science Data Center, Beijing 100101, China
| | - Yan Lv
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; National Ecological Science Data Center, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mengyu Zhang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; National Ecological Science Data Center, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qian Xu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; National Ecological Science Data Center, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Weihua Liu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; National Ecological Science Data Center, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yonghong Zhang
- National Ecological Science Data Center, Beijing 100101, China; State Key Laboratory of Grassland Agro-ecosystems, School of Ecology, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Tianxiang Wang
- National Ecological Science Data Center, Beijing 100101, China; State Key Laboratory of Grassland Agro-ecosystems, School of Ecology, Lanzhou University, Lanzhou, Gansu, 730000, China
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50
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Panda KC, Singh RM, Singh VK, Singla S, Paramaguru PK. Impact of climate change induced future rainfall variation on dynamics of arid-humid zone transition in the western province of India. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 325:116646. [PMID: 36335699 DOI: 10.1016/j.jenvman.2022.116646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 09/26/2022] [Accepted: 10/26/2022] [Indexed: 06/16/2023]
Abstract
The transition of the Earth's climate from one zone to another is one of the major causes behind biodiversity loss, rural-urban migration, and increasing food crises. The rising rate of arid-humid zone transition due to climate change has been substantially visible in the last few decades. However, the precise quantification of the climate change-induced rainfall variation on the climate zone transition still remained a challenge. To solve the issue, the Representative Grid Location-Multivariate Adaptive Regression Spline (RGL-MARS) downscaling algorithm was coupled with the Koppen climate classification scheme to project future changes in various climate zones for the study area. It was observed that the performance of the model was better for the humid clusters compared to the arid clusters. It was noticed that, by the end of the 21st century, the arid region would increase marginally and the humid region would rise by 24.28-36.09% for the western province of India. In contrast, the area of the semi-arid and semi-humid regions would decline for the study area. It was observed that there would be an extensive conversion of semi-humid to humid zone in the peripheral region of the Arabian sea due to the strengthening of land-sea thermal contrast caused by climate change. Similarly, semi-arid to arid zone conversion would also increase due to the inflow of dry air from the Arabian region. The current research would be helpful for the researchers and policymakers to take appropriate measures to reduce the rate of climate zone transition, thereby developing the socioeconomic status of the rural and urban populations.
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Affiliation(s)
- Kanhu Charan Panda
- Department of Agricultural Engineering, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, UP, 221005, India; Department of Soil Conservation, National PG College (Barhalganj), DDU Gorakhpur University, Gorakhpur, UP, 273402, India.
| | - R M Singh
- Department of Agricultural Engineering, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, UP, 221005, India.
| | - Vijay Kumar Singh
- Department of Soil and Water Conservation Engineering, Mahamaya College of Agriculture Engineering and Technology, Acharya Narendra Deva University of Agriculture And Technology, Kumarganj, Ayodhya, UP, 224229, India.
| | - Saurav Singla
- Department of Agricultural Engineering, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, UP, 221005, India.
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