1
|
Zheng C, Wang S, Chen J, Xiang N, Sun L, Chen B, Fu Z, Zhu K, He X. Divergent impacts of VPD and SWC on ecosystem carbon-water coupling under different dryness conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:167007. [PMID: 37739082 DOI: 10.1016/j.scitotenv.2023.167007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 09/08/2023] [Accepted: 09/09/2023] [Indexed: 09/24/2023]
Abstract
Ecosystem water use efficiency (WUE) is an indicator of carbon-water interactions and is defined as the ratio of gross primary productivity (GPP) to evapotranspiration (ET). However, it is currently unclear how WUE responds to atmospheric and soil drought events in terrestrial ecosystems with different dryness conditions. Additionally, the contributions of GPP and ET to the WUE response remain poorly understood. Based on measurements from 26 flux tower sites distributed worldwide, the binning method and random forest model were employed to separate the sensitivities of daily ecosystem WUE, GPP, and ET to vapor pressure deficit (VPD) and soil water content (SWC) under different dryness conditions (dryness index = potential evapotranspiration/precipitation, DI). Results showed that the sensitivity of WUE to VPD was negative at humid sites (DI < 1), while the sensitivity of WUE to SWC was positive at arid sites (DI > 2). Furthermore, the contribution of GPP to VPD-induced WUE variability was 63 % at humid sites, and the contribution of ET to SWC-induced WUE variability was 68 % when SWC was less than the 60th percentile at arid sites. Consequently, one increasing VPD-induced decrease in GPP was generally linked to a decrease in WUE at humid sites, and one drying soil moisture-caused decrease in ET was linked to a WUE increase under low SWC conditions at arid sites. Finally, VPD had a stronger effect on WUE than SWC when VPD was less than the 90th percentile or SWC was greater than the 50th percentile. Our findings underscore the importance of considering ecosystem dryness when investigating the impacts of VPD and SWC on ecosystem carbon-water coupling.
Collapse
Affiliation(s)
- Chen Zheng
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shaoqiang Wang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China; Key Laboratory of Regional Ecological Process and Environment Evolution, School of Geography and Information Engineering, Chinese University of Geosciences, Wuhan 430074, China.
| | - Jinghua Chen
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ning Xiang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Leigang Sun
- Institute of Geographical Sciences, Hebei Academy of Sciences, Shijiazhuang 050011, China; Hebei Technology Innovation Center for Geographic Information Application, Shijiazhuang 050011, China.
| | - Bin Chen
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zheng Fu
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
| | - Kai Zhu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinlei He
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
| |
Collapse
|
2
|
Hoover DL, Abendroth LJ, Browning DM, Saha A, Snyder K, Wagle P, Witthaus L, Baffaut C, Biederman JA, Bosch DD, Bracho R, Busch D, Clark P, Ellsworth P, Fay PA, Flerchinger G, Kearney S, Levers L, Saliendra N, Schmer M, Schomberg H, Scott RL. Indicators of water use efficiency across diverse agroecosystems and spatiotemporal scales. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 864:160992. [PMID: 36535470 DOI: 10.1016/j.scitotenv.2022.160992] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 11/17/2022] [Accepted: 12/13/2022] [Indexed: 06/17/2023]
Abstract
Understanding the relationship between water and production within and across agroecosystems is essential for addressing several agricultural challenges of the 21st century: providing food, fuel, and fiber to a growing human population, reducing the environmental impacts of agricultural production, and adapting food systems to climate change. Of all human activities, agriculture has the highest demand for water globally. Therefore, increasing water use efficiency (WUE), or producing 'more crop per drop', has been a long-term goal of agricultural management, engineering, and crop breeding. WUE is a widely used term applied across a diverse array of spatial scales, spanning from the leaf to the globe, and over temporal scales ranging from seconds to months to years. The measurement, interpretation, and complexity of WUE varies enormously across these spatial and temporal scales, challenging comparisons within and across diverse agroecosystems. The goals of this review are to evaluate common indicators of WUE in agricultural production and assess tradeoffs when applying these indicators within and across agroecosystems amidst a changing climate. We examine three questions: (1) what are the uses and limitations of common WUE indicators, (2) how can WUE indicators be applied within and across agroecosystems, and (3) how can WUE indicators help adapt agriculture to climate change? Addressing these agricultural challenges will require land managers, producers, policy makers, researchers, and consumers to evaluate costs and benefits of practices and innovations of water use in agricultural production. Clearly defining and interpreting WUE in the most scale-appropriate way is crucial for advancing agroecosystem sustainability.
Collapse
Affiliation(s)
- David L Hoover
- USDA-ARS, Rangeland Resources and Systems Research Unit, Crops Research Laboratory, Fort Collins, CO, USA.
| | - Lori J Abendroth
- USDA-ARS, Cropping Systems and Water Quality Research Unit, Columbia, MO, USA
| | - Dawn M Browning
- USDA-ARS, Range Management Research Unit, Las Cruces, NM, USA
| | - Amartya Saha
- Archbold Biological Station, Agroecology Laboratory, Lake Placid, FL, USA
| | - Keirith Snyder
- USDA-ARS, Great Basin Rangelands Research Unit, Reno, NV, USA
| | - Pradeep Wagle
- USDA-ARS, Grazinglands Research Laboratory, El Reno, OK, USA
| | | | - Claire Baffaut
- USDA-ARS, Cropping Systems and Water Quality Research Unit, Columbia, MO, USA
| | | | - David D Bosch
- USDA-ARS, Southeast Watershed Research Laboratory, Tifton, GA, USA
| | - Rosvel Bracho
- School of Forests, Fisheries and Geomatics Sciences, University of Florida, Gainesville, FL, USA
| | - Dennis Busch
- School of Agriculture, University of Wisconsin-Platteville, Platteville, WI, USA
| | - Patrick Clark
- USDA-ARS, Northwest Watershed Research Center, Boise, ID, USA
| | | | - Philip A Fay
- USDA-ARS, Grassland Soil and Water Research Laboratory, Temple, TX, USA
| | | | - Sean Kearney
- USDA-ARS, Rangeland Resources and Systems Research Unit, Crops Research Laboratory, Fort Collins, CO, USA
| | - Lucia Levers
- USDA-ARS, Sustainable Agriculture Water Systems, Davis, CA, USA
| | - Nicanor Saliendra
- USDA-ARS, Northern Great Plains Research Laboratory, Mandan, ND, USA
| | - Marty Schmer
- USDA-ARS, Agroecosystems Management Research Unit, Lincoln, NE, USA
| | - Harry Schomberg
- USDA-ARS, Sustainable Agricultural Systems Laboratory, Beltsville Agricultural Research Center, Beltsville, MD, USA
| | - Russell L Scott
- USDA-ARS, Southwest Watershed Research Center, Tucson, AZ, USA
| |
Collapse
|
3
|
Liu X, Ziaco E, Biondi F. Water-Use Efficiency of Co-occurring Sky-Island Pine Species in the North American Great Basin. FRONTIERS IN PLANT SCIENCE 2021; 12:787297. [PMID: 34925427 PMCID: PMC8678526 DOI: 10.3389/fpls.2021.787297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/02/2021] [Indexed: 06/14/2023]
Abstract
Water-use efficiency (WUE), weighing the balance between plant transpiration and growth, is a key characteristic of ecosystem functioning and a component of tree drought resistance. Seasonal dynamics of tree-level WUE and its connections with drought variability have not been previously explored in sky-island montane forests. We investigated whole-tree transpiration and stem growth of bristlecone (Pinus longaeva) and limber pine (Pinus flexilis) within a high-elevation stand in central-eastern Nevada, United States, using sub-hourly measurements over 5 years (2013-2017). A moderate drought was generally observed early in the growing season, whereas interannual variability of summer rains determined drought levels between years, i.e., reducing drought stress in 2013-2014 while enhancing it in 2015-2017. Transpiration and basal area increment (BAI) of both pines were coupled throughout June-July, resulting in a high but relatively constant early season WUE. In contrast, both pines showed high interannual plasticity in late-season WUE, with a predominant role of stem growth in driving WUE. Overall, bristlecone pine was characterized by a lower WUE compared to limber pine. Dry or wet episodes in the late growing season overrode species differences. Our results suggested thresholds of vapor pressure deficit and soil moisture that would lead to opposite responses of WUE to late-season dry or wet conditions. These findings provide novel insights and clarify potential mechanisms modulating tree-level WUE in sky-island ecosystems of semi-arid regions, thereby helping land managers to design appropriate science-based strategies and reduce uncertainties associated with the impact of future climatic changes.
Collapse
Affiliation(s)
- Xinsheng Liu
- School of Geography and Tourism, Anhui Normal University, Wuhu, China
- DendroLab, Department of Natural Resources and Environmental Science, University of Nevada, Reno, NV, United States
- College of Tourism and Geography, Jiujiang University, Jiujiang, China
| | - Emanuele Ziaco
- Department of Ecology and Genetics, Plant Ecology and Evolution, University of Uppsala, Uppsala, Sweden
| | - Franco Biondi
- DendroLab, Department of Natural Resources and Environmental Science, University of Nevada, Reno, NV, United States
| |
Collapse
|
4
|
Knowles JF, Scott RL, Biederman JA, Blanken PD, Burns SP, Dore S, Kolb TE, Litvak ME, Barron-Gafford GA. Montane forest productivity across a semiarid climatic gradient. GLOBAL CHANGE BIOLOGY 2020; 26:6945-6958. [PMID: 32886444 DOI: 10.1111/gcb.15335] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 08/18/2020] [Accepted: 08/20/2020] [Indexed: 06/11/2023]
Abstract
High-elevation montane forests are disproportionately important to carbon sequestration in semiarid climates where low elevations are dry and characterized by low carbon density ecosystems. However, these ecosystems are increasingly threatened by climate change with seasonal implications for photosynthesis and forest growth. As a result, we leveraged eddy covariance data from six evergreen conifer forest sites in the semiarid western United States to extrapolate the status of carbon sequestration within a framework of projected warming and drying. At colder locations, the seasonal evolution of gross primary productivity (GPP) was characterized by a single broad maximum during the summer that corresponded to snow melt-derived moisture and a transition from winter dormancy to spring activity. Conversely, winter dormancy was transient at warmer locations, and GPP was responsive to both winter and summer precipitation such that two distinct GPP maxima were separated by a period of foresummer drought. This resulted in a predictable sequence of primary limiting factors to GPP beginning with air temperature in winter and proceeding to moisture and leaf area during the summer. Due to counteracting winter (positive) and summer (negative) GPP responses to warming, leaf area index and moisture availability were the best predictors of annual GPP differences across sites. Overall, mean annual GPP was greatest at the warmest site due to persistent vegetation photosynthetic activity throughout the winter. These results indicate that the trajectory of this region's carbon sequestration will be sensitive to reduced or delayed summer precipitation, especially if coupled to snow drought and earlier soil moisture recession, but summer precipitation changes remain highly uncertain. Given the demonstrated potential for seasonally offsetting responses to warming, we project that decadal semiarid montane forest carbon sequestration will remain relatively stable in the absence of severe disturbance.
Collapse
Affiliation(s)
- John F Knowles
- Southwest Watershed Research Center, USDA Agricultural Research Service, Tucson, AZ, USA
- School of Geography, Development & Environment, University of Arizona, Tucson, AZ, USA
| | - Russell L Scott
- Southwest Watershed Research Center, USDA Agricultural Research Service, Tucson, AZ, USA
| | - Joel A Biederman
- Southwest Watershed Research Center, USDA Agricultural Research Service, Tucson, AZ, USA
| | - Peter D Blanken
- Department of Geography, University of Colorado Boulder, Boulder, CO, USA
| | - Sean P Burns
- Department of Geography, University of Colorado Boulder, Boulder, CO, USA
- National Center for Atmospheric Research, Boulder, CO, USA
| | - Sabina Dore
- School of Forestry, Northern Arizona University, Flagstaff, AZ, USA
| | - Thomas E Kolb
- School of Forestry, Northern Arizona University, Flagstaff, AZ, USA
| | - Marcy E Litvak
- Department of Biology, University of New Mexico, Albuquerque, NM, USA
| | - Greg A Barron-Gafford
- School of Geography, Development & Environment, University of Arizona, Tucson, AZ, USA
| |
Collapse
|
5
|
Liu R, Li Y, Wang Y, Ma J, Cieraad E. Variation of water use efficiency across seasons and years: Different role of herbaceous plants in desert ecosystem. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 647:827-835. [PMID: 30096672 DOI: 10.1016/j.scitotenv.2018.08.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 08/03/2018] [Indexed: 06/08/2023]
Abstract
Desert ecosystems often structured in two distinct layers of woody and herbaceous plants. Changes in community composition alter the fractional coverage by bare soil, woody and herbaceous plants, with potential effects on water and carbon fluxes. We used eddy covariance measurements and chamber method in two similar shrub-dominated desert communities (Tamarix community and Haloxylon community) to assess inter- and intra-annual variations of ecosystem water use efficiency (EWUE) (where we distinguished whole ecosystem EWUE as EWUEE, and EWUE of shrub and herbaceous layers as EWUEShrub and EWUEHerb) in central Asia. In the Tamarix community, 11 years of carbon and water fluxes showed that years with larger herbaceous cover (referred to as shrub-herb years) had significant higher EWUEE than years with lower herbaceous cover (referred to as shrub years), with the values of 1.07 ± 0.11 vs. 0.68 ± 0.03 g C/kg H2O. There was a significant positive correlation between EWUEE and the maximum herbaceous plants cover. In the Haloxylon community, chamber measurements during a shrub year demonstrated that the shrub layer contributed most to the gross ecosystem productivity (GEP) and evapotranspiration (ET) of the system, with the herbaceous layer contributing around 30% at the beginning of the growing season, and decreasing to nearly zero during the middle and at the end of the growing season. The shrub layer EWUEShrub was significant higher than that in the herbaceous layer (EWUEHerb) throughout the growing season (1.82 ± 0.11 vs. 1.06 ± 0.32 g C/kg H2O). EWUEShrub was positively correlated with EWUEE, but there was no relationship between EWUEHerb and EWUEE in a shrub year. This study shows that the variability of the herbaceous layer across seasons and years in these desert ecosystems is crucial for predicting water and carbon cycling under ongoing and projected climatic change scenarios in shrub-dominated desert ecosystems.
Collapse
Affiliation(s)
- Ran Liu
- State Key Lab of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 818 South Beijing Road, Urumqi, Xinjiang 830011, China.
| | - Yan Li
- State Key Lab of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 818 South Beijing Road, Urumqi, Xinjiang 830011, China
| | - Yugang Wang
- State Key Lab of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 818 South Beijing Road, Urumqi, Xinjiang 830011, China
| | - Jie Ma
- State Key Lab of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 818 South Beijing Road, Urumqi, Xinjiang 830011, China
| | - Ellen Cieraad
- Institute of Environmental Sciences CML, Leiden University, Einsteinweg 2, 2333 CC, Leiden, the Netherlands
| |
Collapse
|
6
|
Yi K, Maxwell JT, Wenzel MK, Roman DT, Sauer PE, Phillips RP, Novick KA. Linking variation in intrinsic water-use efficiency to isohydricity: a comparison at multiple spatiotemporal scales. THE NEW PHYTOLOGIST 2019; 221:195-208. [PMID: 30117538 DOI: 10.1111/nph.15384] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 07/06/2018] [Indexed: 06/08/2023]
Abstract
Species-specific responses of plant intrinsic water-use efficiency (iWUE) to multiple environmental drivers associated with climate change, including soil moisture (θ), vapor pressure deficit (D), and atmospheric CO2 concentration (ca ), are poorly understood. We assessed how the iWUE and growth of several species of deciduous trees that span a gradient of isohydric to anisohydric water-use strategies respond to key environmental drivers (θ, D and ca ). iWUE was calculated for individual tree species using leaf-level gas exchange and tree-ring δ13 C in wood measurements, and for the whole forest using the eddy covariance method. The iWUE of the isohydric species was generally more sensitive to environmental change than the anisohydric species was, and increased significantly with rising D during the periods of water stress. At longer timescales, the influence of ca was pronounced for isohydric tulip poplar but not for others. Trees' physiological responses to changing environmental drivers can be interpreted differently depending on the observational scale. Care should be also taken in interpreting observed or modeled trends in iWUE that do not explicitly account for the influence of D.
Collapse
Affiliation(s)
- Koong Yi
- School of Public and Environmental Affairs, Indiana University Bloomington, 1315 East Tenth Street, Bloomington, IN, 47405, USA
| | - Justin T Maxwell
- Department of Geography, Indiana University Bloomington, 701 East Kirkwood Avenue, Bloomington, IN, 47405, USA
| | - Matthew K Wenzel
- School of Public and Environmental Affairs, Indiana University Bloomington, 1315 East Tenth Street, Bloomington, IN, 47405, USA
| | - D Tyler Roman
- US Department of Agriculture Forest Service, Northern Research Station, 1831 Highway 169 East, Grand Rapids, MN, 55744, USA
| | - Peter E Sauer
- Department of Geological Science, Indiana University Bloomington, 1001 East Tenth Street, Bloomington, IN, 47405, USA
| | - Richard P Phillips
- Department of Biology, Indiana University Bloomington, 1001 East Third Street, Bloomington, IN, 47405, USA
| | - Kimberly A Novick
- School of Public and Environmental Affairs, Indiana University Bloomington, 1315 East Tenth Street, Bloomington, IN, 47405, USA
| |
Collapse
|
7
|
Medlyn BE, De Kauwe MG, Lin YS, Knauer J, Duursma RA, Williams CA, Arneth A, Clement R, Isaac P, Limousin JM, Linderson ML, Meir P, Martin-StPaul N, Wingate L. How do leaf and ecosystem measures of water-use efficiency compare? THE NEW PHYTOLOGIST 2017; 216:758-770. [PMID: 28574148 DOI: 10.1111/nph.14626] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Accepted: 04/18/2017] [Indexed: 06/07/2023]
Abstract
The terrestrial carbon and water cycles are intimately linked: the carbon cycle is driven by photosynthesis, while the water balance is dominated by transpiration, and both fluxes are controlled by plant stomatal conductance. The ratio between these fluxes, the plant water-use efficiency (WUE), is a useful indicator of vegetation function. WUE can be estimated using several techniques, including leaf gas exchange, stable isotope discrimination, and eddy covariance. Here we compare global compilations of data for each of these three techniques. We show that patterns of variation in WUE across plant functional types (PFTs) are not consistent among the three datasets. Key discrepancies include the following: leaf-scale data indicate differences between needleleaf and broadleaf forests, but ecosystem-scale data do not; leaf-scale data indicate differences between C3 and C4 species, whereas at ecosystem scale there is a difference between C3 and C4 crops but not grasslands; and isotope-based estimates of WUE are higher than estimates based on gas exchange for most PFTs. Our study quantifies the uncertainty associated with different methods of measuring WUE, indicates potential for bias when using WUE measures to parameterize or validate models, and indicates key research directions needed to reconcile alternative measures of WUE.
Collapse
Affiliation(s)
- Belinda E Medlyn
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Martin G De Kauwe
- Department of Biological Science, Macquarie University, North Ryde, NSW, 2109, Australia
| | - Yan-Shih Lin
- Department of Biological Science, Macquarie University, North Ryde, NSW, 2109, Australia
- Ecologie et Ecophysiologie Forestières, Centre INRA de Nancy-Lorraine, Route d'Amance, Champenoux, 54280, France
| | - Jürgen Knauer
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, 07745, Germany
| | - Remko A Duursma
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
| | - Christopher A Williams
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia
- Graduate School of Geography, Clark University, 950 Main Street, Worcester, MA, 01602, USA
| | - Almut Arneth
- Department of Atmospheric Environmental Research (IMK-IFU), Karlsruhe Institute of Technology, Kreuzeckbahnstr. 19, Garmisch-Partenkirchen, 82467, Germany
| | - Rob Clement
- School of Geosciences, University of Edinburgh, Edinburgh, EH9 3FF, UK
| | | | - Jean-Marc Limousin
- Centre d'Ecologie Fonctionnelle et Evolutive CEFE, UMR 5175, CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE, 1919 Route de Mende, Montpellier Cedex 5, 34293, France
| | - Maj-Lena Linderson
- Department of Physical Geography and Ecosystem Science, Lund University, Sölvegatan 12, Lund, SE, 262 33, Sweden
| | - Patrick Meir
- School of Geosciences, University of Edinburgh, Edinburgh, EH9 3FF, UK
- Research School of Biology, Australian National University, Canberra, ACT, 2601, Australia
| | | | - Lisa Wingate
- Bordeaux Sciences Agro, ISPA, INRA, Villenave d'Ornon, 33140, France
| |
Collapse
|
8
|
Monitoring Changes in Water Use Efficiency to Understand Drought Induced Tree Mortality. FORESTS 2017. [DOI: 10.3390/f8100365] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
9
|
Albert LP, Keenan TF, Burns SP, Huxman TE, Monson RK. Climate controls over ecosystem metabolism: insights from a fifteen-year inductive artificial neural network synthesis for a subalpine forest. Oecologia 2017; 184:25-41. [PMID: 28343362 DOI: 10.1007/s00442-017-3853-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Accepted: 03/13/2017] [Indexed: 11/30/2022]
Abstract
Eddy covariance (EC) datasets have provided insight into climate determinants of net ecosystem productivity (NEP) and evapotranspiration (ET) in natural ecosystems for decades, but most EC studies were published in serial fashion such that one study's result became the following study's hypothesis. This approach reflects the hypothetico-deductive process by focusing on previously derived hypotheses. A synthesis of this type of sequential inference reiterates subjective biases and may amplify past assumptions about the role, and relative importance, of controls over ecosystem metabolism. Long-term EC datasets facilitate an alternative approach to synthesis: the use of inductive data-based analyses to re-examine past deductive studies of the same ecosystem. Here we examined the seasonal climate determinants of NEP and ET by analyzing a 15-year EC time-series from a subalpine forest using an ensemble of Artificial Neural Networks (ANNs) at the half-day (daytime/nighttime) time-step. We extracted relative rankings of climate drivers and driver-response relationships directly from the dataset with minimal a priori assumptions. The ANN analysis revealed temperature variables as primary climate drivers of NEP and daytime ET, when all seasons are considered, consistent with the assembly of past studies. New relations uncovered by the ANN approach include the role of soil moisture in driving daytime NEP during the snowmelt period, the nonlinear response of NEP to temperature across seasons, and the low relevance of summer rainfall for NEP or ET at the same daytime/nighttime time step. These new results offer a more complete perspective of climate-ecosystem interactions at this site than traditional deductive analyses alone.
Collapse
Affiliation(s)
- Loren P Albert
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721, USA.
| | - Trevor F Keenan
- Lawrence Berkeley National Laboratory, Berkeley, CA, 94709, USA
| | - Sean P Burns
- Department of Geography, University of Colorado, Boulder, CO, 80309, USA.,National Center for Atmospheric Research, Boulder, CO, 80307, USA
| | - Travis E Huxman
- Ecology and Evolutionary Biology and Center for Environmental Biology, University of California, Irvine, CA, 92697, USA
| | - Russell K Monson
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721, USA.,Laboratory of Tree Ring Research, University of Arizona, Tucson, AZ, 85721, USA
| |
Collapse
|
10
|
Malone SL, Tulbure MG, Pérez‐Luque AJ, Assal TJ, Bremer LL, Drucker DP, Hillis V, Varela S, Goulden ML. Drought resistance across California ecosystems: evaluating changes in carbon dynamics using satellite imagery. Ecosphere 2016. [DOI: 10.1002/ecs2.1561] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Sparkle L. Malone
- United States Forest Service Rocky Mountain Research Station 240 West Prospect Road Fort Collins Colorado 80524 USA
| | - Mirela G. Tulbure
- School of Biological, Earth and Environmental Science The University of New South Wales Sydney New South Wales 2052 Australia
| | - Antonio J. Pérez‐Luque
- Laboratory of Ecology (iEcolab) Andalusian Institute for Earth System Research Andalusian Center for Environmental Research University of Granada Avda. Mediterráneo s/n Granada 18006 Spain
| | - Timothy J. Assal
- United States Geological Survey Fort Collins Science Center Fort Collins Colorado 80526 USA
| | - Leah L. Bremer
- The Natural Capital Project The Stanford Woods Institute for the Environment Stanford University 371 Serra Mall Stanford California 94305 USA
| | - Debora P. Drucker
- Embrapa Informática Agropecuária Av. André Tosello, 209, Campus Unicamp 13083‐886 Campinas SP Brazil
| | - Vicken Hillis
- Department of Environmental Science and Policy University of California, Davis One Shields Avenue Davis California 95616 USA
| | - Sara Varela
- Museum für Naturkunde Leibniz Institute for Evolution and Biodiversity Science Invalidenstr. 43 10115 Berlin Germany
| | - Michael L. Goulden
- Department of Earth System Science University of California Irvine California 92697 USA
| |
Collapse
|
11
|
Maurer GE, Chan AM, Trahan NA, Moore DJP, Bowling DR. Carbon isotopic composition of forest soil respiration in the decade following bark beetle and stem girdling disturbances in the Rocky Mountains. PLANT, CELL & ENVIRONMENT 2016; 39:1513-1523. [PMID: 26824577 DOI: 10.1111/pce.12716] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 01/17/2016] [Indexed: 06/05/2023]
Abstract
Bark beetle outbreaks are widespread in western North American forests, reducing primary productivity and transpiration, leading to forest mortality across large areas and altering ecosystem carbon cycling. Here the carbon isotope composition (δ(13) C) of soil respiration (δJ ) was monitored in the decade after disturbance for forests affected naturally by mountain pine beetle infestation and artificially by stem girdling. The seasonal mean δJ changed along both chronosequences. We found (a) enrichment of δJ relative to controls (<1 ‰) in near-surface soils in the first 2 years after disturbance; (b) depletion (1‰ or no change) during years 3-7; and (c) a second period of enrichment (1-2‰) in years 8-10. Results were consistent with isotopic patterns associated with the gradual death and decomposition of rhizosphere organisms, fine roots, conifer needles and woody roots and debris over the course of a decade after mortality. Finally, δJ was progressively more (13) C-depleted deeper in the soil than near the surface, while the bulk soil followed the well-established pattern of (13) C-enrichment at depth. Overall, differences in δJ between mortality classes (<1‰) and soil depths (<3‰) were smaller than variability within a class or depth over a season (up to 6‰).
Collapse
Affiliation(s)
- Gregory E Maurer
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Allison M Chan
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA
| | - Nicole A Trahan
- School of Natural Resources and the Environment, University of Arizona, 1064 E. Lowell St., Tucson, AZ, 85721, USA
| | - David J P Moore
- School of Natural Resources and the Environment, University of Arizona, 1064 E. Lowell St., Tucson, AZ, 85721, USA
| | - David R Bowling
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA
| |
Collapse
|
12
|
Ecosystem Water-Use Efficiency of Annual Corn and Perennial Grasslands: Contributions from Land-Use History and Species Composition. Ecosystems 2016. [DOI: 10.1007/s10021-016-9981-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
13
|
Zhang J, Ren W, An P, Pan Z, Wang L, Dong Z, He D, Yang J, Pan S, Tian H. Responses of Crop Water Use Efficiency to Climate Change and Agronomic Measures in the Semiarid Area of Northern China. PLoS One 2015; 10:e0137409. [PMID: 26336098 PMCID: PMC4559399 DOI: 10.1371/journal.pone.0137409] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 08/17/2015] [Indexed: 11/18/2022] Open
Abstract
It has long been concerned how crop water use efficiency (WUE) responds to climate change. Most of existing researches have emphasized the impact of single climate factor but have paid less attention to the effect of developed agronomic measures on crop WUE. Based on the long-term field observations/experiments data, we investigated the changing responses of crop WUE to climate variables (temperature and precipitation) and agronomic practices (fertilization and cropping patterns) in the semi-arid area of northern China (SAC) during two periods, 1983–1999 and 2000–2010 (drier and warmer). Our results suggest that crop WUE was an intrinsical system sensitive to climate change and agronomic measures. Crops tend to reach the maximum WUE (WUEmax) in warm-dry environment while reach the stable minimum WUE (WUEmin) in warm-wet environment, with a difference between WUEmax and WUEmin ranging from 29.0%-55.5%. Changes in temperature and precipitation in the past three decades jointly enhanced crop WUE by 8.1%-30.6%. Elevated fertilizer and rotation cropping would increase crop WUE by 5.6–11.0% and 19.5–92.9%, respectively. These results indicate crop has the resilience by adjusting WUE, which is not only able to respond to subsequent periods of favorable water balance but also to tolerate the drought stress, and reasonable agronomic practices could enhance this resilience. However, this capacity would break down under impact of climate changes and unconscionable agronomic practices (e.g. excessive N/P/K fertilizer or traditional continuous cropping). Based on the findings in this study, a conceptual crop WUE model is constructed to indicate the threshold of crop resilience, which could help the farmer develop appropriate strategies in adapting the adverse impacts of climate warming.
Collapse
Affiliation(s)
- Jingting Zhang
- College of Resources and Environmental Science, China Agricultural University, Beijing, 100193, China
- Key Ecology and Environment Experimental Station of Ministry of Agriculture for Field Scientific Observation in Hohhot, Wuchuan, Hohhot, 011705, China
| | - Wei Ren
- Department of Plant & Soil Sciences, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, 40506, United States of America
- International Center for Climate and Global Change Research, Auburn University, Auburn, AL, 36849, United States of America
| | - Pingli An
- College of Resources and Environmental Science, China Agricultural University, Beijing, 100193, China
- Key Ecology and Environment Experimental Station of Ministry of Agriculture for Field Scientific Observation in Hohhot, Wuchuan, Hohhot, 011705, China
- * E-mail:
| | - Zhihua Pan
- College of Resources and Environmental Science, China Agricultural University, Beijing, 100193, China
- Key Ecology and Environment Experimental Station of Ministry of Agriculture for Field Scientific Observation in Hohhot, Wuchuan, Hohhot, 011705, China
| | - Liwei Wang
- College of Resources and Environmental Science, China Agricultural University, Beijing, 100193, China
- Key Ecology and Environment Experimental Station of Ministry of Agriculture for Field Scientific Observation in Hohhot, Wuchuan, Hohhot, 011705, China
| | - Zhiqiang Dong
- College of Resources and Environmental Science, China Agricultural University, Beijing, 100193, China
- Key Ecology and Environment Experimental Station of Ministry of Agriculture for Field Scientific Observation in Hohhot, Wuchuan, Hohhot, 011705, China
| | - Di He
- College of Resources and Environmental Science, China Agricultural University, Beijing, 100193, China
| | - Jia Yang
- International Center for Climate and Global Change Research, Auburn University, Auburn, AL, 36849, United States of America
| | - Shufen Pan
- International Center for Climate and Global Change Research, Auburn University, Auburn, AL, 36849, United States of America
| | - Hanqin Tian
- International Center for Climate and Global Change Research, Auburn University, Auburn, AL, 36849, United States of America
| |
Collapse
|
14
|
Bourne AE, Haigh AM, Ellsworth DS. Stomatal sensitivity to vapour pressure deficit relates to climate of origin in Eucalyptus species. TREE PHYSIOLOGY 2015; 35:266-278. [PMID: 25769338 DOI: 10.1093/treephys/tpv014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 01/24/2015] [Indexed: 06/04/2023]
Abstract
Selecting plantation species to balance water use and production requires accurate models for predicting how species will tolerate and respond to environmental conditions. Although interspecific variation in water use occurs, species-specific parameters are rarely incorporated into physiologically based models because often the appropriate species parameters are lacking. To determine the physiological control over water use in Eucalyptus, five stands of Eucalyptus species growing in a common garden were measured for sap flux rates and their stomatal response to vapour pressure deficit (D) was assessed. Maximal canopy conductance and whole-canopy stomatal sensitivity to D and reduced water availability were lower in species originating from more arid climates of origin than those from humid climates. Species from humid climates showed a larger decline in maximal sap flux density (JSmax) with reduced water availability, and a lower D at which stomatal closure occurred than species from more arid climates, implying larger sensitivity to water availability and D in these species. We observed significant (P < 0.05) correlations of species climate of origin with mean vessel diameter (R(2) = 0.90), stomatal sensitivity to D (R(2) = 0.83) and the size of the decline in JSmax to restricted water availability (R(2) = 0.94). Thus aridity of climate of origin appears to have a selective role in constraining water-use response among the five Eucalyptus plantation species. These relationships emphasize that within this congeneric group of species, climate aridity constrains water use. These relationships have implications for species choices for tree plantation success against drought-induced losses and the ability to manage Eucalyptus plantations against projected changes in water availability and evaporation in the future.
Collapse
Affiliation(s)
- Aimee E Bourne
- Hawkesbury Institute for the Environment, University of Western Sydney, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Anthony M Haigh
- School of Science and Health, University of Western Sydney, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - David S Ellsworth
- Hawkesbury Institute for the Environment, University of Western Sydney, Locked Bag 1797, Penrith, NSW 2751, Australia
| |
Collapse
|
15
|
Ecosystem resilience despite large-scale altered hydroclimatic conditions. Nature 2013; 494:349-52. [PMID: 23334410 DOI: 10.1038/nature11836] [Citation(s) in RCA: 356] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 12/03/2012] [Indexed: 11/08/2022]
Abstract
Climate change is predicted to increase both drought frequency and duration, and when coupled with substantial warming, will establish a new hydroclimatological model for many regions. Large-scale, warm droughts have recently occurred in North America, Africa, Europe, Amazonia and Australia, resulting in major effects on terrestrial ecosystems, carbon balance and food security. Here we compare the functional response of above-ground net primary production to contrasting hydroclimatic periods in the late twentieth century (1975-1998), and drier, warmer conditions in the early twenty-first century (2000-2009) in the Northern and Southern Hemispheres. We find a common ecosystem water-use efficiency (WUE(e): above-ground net primary production/evapotranspiration) across biomes ranging from grassland to forest that indicates an intrinsic system sensitivity to water availability across rainfall regimes, regardless of hydroclimatic conditions. We found higher WUE(e) in drier years that increased significantly with drought to a maximum WUE(e) across all biomes; and a minimum native state in wetter years that was common across hydroclimatic periods. This indicates biome-scale resilience to the interannual variability associated with the early twenty-first century drought--that is, the capacity to tolerate low, annual precipitation and to respond to subsequent periods of favourable water balance. These findings provide a conceptual model of ecosystem properties at the decadal scale applicable to the widespread altered hydroclimatic conditions that are predicted for later this century. Understanding the hydroclimatic threshold that will break down ecosystem resilience and alter maximum WUE(e) may allow us to predict land-surface consequences as large regions become more arid, starting with water-limited, low-productivity grasslands.
Collapse
|