1
|
Zhu X, Shen J, Li Y, Liu X, Xu W, Zhou F, Wang J, Reis S, Wu J. Nitrogen emission and deposition budget in an agricultural catchment in subtropical central China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 289:117870. [PMID: 34385131 DOI: 10.1016/j.envpol.2021.117870] [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: 01/31/2021] [Revised: 06/14/2021] [Accepted: 07/28/2021] [Indexed: 06/13/2023]
Abstract
The study of emissions and depositions of atmospheric reactive nitrogen species (Nrs) in a region is important to uncover the sources and sinks of atmospheric Nrs in the region. In this study, atmospheric total Nrs depositions including both wet-only and dry deposition were monitored simultaneously across major land-use types in a 105 km2 catchment called Jinjing River Catchment (JRC) in subtropical central China from 2015 to 2016. Based on activity data and emission factors for the main Nrs emission sources, ammonia (NH3) and nitrogen oxides (NOx) emission inventories for the catchment were also compiled. The estimated total Nrs deposition in JRC was 35.9 kg N ha-1 yr-1, with approximately 49.7 % attributed to reduced compounds (NHx), and 40.5 % attributed to oxidized (NOy). The total Nrs emission rate in JRC was 80.4 kg N ha-1 yr-1, with 61.5 and 18.9 kg N ha-1 yr-1 from NH3 and NOx emissions, respectively. Livestock excretion and fertilization were the two main contributing emission sources for NH3, while vehicle sources contributed the bulk of NOx emissions. The net atmospheric budgets of Nrs in paddy field, forest, and tea field were +3.7, -36.1, and +23.8 kg N ha-1 yr-1, respectively. At the catchment scale, the net atmospheric budget of Nrs was +47.7 kg N ha-1 yr-1, with +43.7 kg N ha-1 yr-1 of NHx and +4.0 kg N ha-1 yr-1 of NOy, indicating that the subtropical catchment was net sources of atmospheric Nrs. Considering that excessive atmospheric Nr emissions and deposition may cause adverse effects on the environment, effects should be conducted to mitigate the Nrs emissions from agriculture and transportation, and increasing the area of forest is good for reducing the net positive budget of atmospheric Nrs in the subtropical catchments in China.
Collapse
Affiliation(s)
- Xiao Zhu
- Key Laboratory of Agro-ecological Processes in Subtropical Region and Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jianlin Shen
- Key Laboratory of Agro-ecological Processes in Subtropical Region and Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China.
| | - Yong Li
- Key Laboratory of Agro-ecological Processes in Subtropical Region and Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China
| | - Xuejun Liu
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Wen Xu
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Feng Zhou
- College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Juan Wang
- Key Laboratory of Agro-ecological Processes in Subtropical Region and Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China
| | - Stefan Reis
- UK Centre for Ecology & Hydrology, Bush Estate, Penicuik, Midlothian, EH26 0QB, UK; University of Exeter Medical School, European Centre for Environment and Health, Knowledge Spa, Truro, TR1 3HD, UK
| | - Jinshui Wu
- Key Laboratory of Agro-ecological Processes in Subtropical Region and Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, China
| |
Collapse
|
2
|
Li Y, Li L, Sun W, Yin X. Nitrate sources and transformations along a mountain-to-plain gradient in the Taizi River basin in Northeast China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:58284-58297. [PMID: 34115303 DOI: 10.1007/s11356-021-14762-0] [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: 11/30/2020] [Accepted: 06/02/2021] [Indexed: 06/12/2023]
Abstract
Fifty-seven riverine samples in three typical regions, namely, upper mountainous (zone 1), middle hilly (zone 2), and lower plain (zone 3) regions, were collected in May (low flow) and August (high flow) of 2016, and chemical parameters and isotopes were analyzed to enrich the knowledge of riverine nitrate sources and transformations in the Taizi River basin. Results showed that NO3- concentrations in zone 3 were the highest, followed by zones 2 and 1. NO3-/Cl- molar ratios and nitrate dual isotopes indicated that NO3- was mainly from chemical fertilizer (CF) in zones 1 (57.0%) and 2 (43.1%) according to a Bayesian mixing model (SIAR) and mixed sources of CF, nitrification of soil organic nitrogen (SON), and manure and sewage (M&S) in zone 3 (92.8%), during the high-flow season. NO3- was mainly from CF and SON in zones 1 (76.7%) and 2 (74.0%), during the low-flow season. NO3-sources were different in the three rivers of zone 3 mainly due to various urban inputs. Contributions of CF, SON, and M&S increased by 13%, 8.3%, and 7.5% in zones 1, 2, and 3, respectively, from the low-flow to the high-flow season. NO3- in the Taizi River was mainly influenced by nitrification in soils, while no significant denitrification was found in the three zones. Measures for reducing NO3- inputs to rivers should be considered by improving effectively utilizing rate of chemical fertilizer and inhibit nitrification.
Collapse
Affiliation(s)
- Yanli Li
- Institute of Resources and Environment, Henan Polytechnic University, Jiaozuo, 454000, China.
| | - Linxia Li
- Institute of Resources and Environment, Henan Polytechnic University, Jiaozuo, 454000, China
- Henan Key Laboratory for Environmental Monitoring Technology, Zhengzhou, 454000, China
| | - Wei Sun
- Institute of Resources and Environment, Henan Polytechnic University, Jiaozuo, 454000, China
| | - Xijie Yin
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, 361000, China
| |
Collapse
|
3
|
Sun F, Deng Q, Li X, Tang M, Ma X, Cao X, Zhou Y, Song C. Organic carbon quantity and quality jointly triggered the switch between dissimilatory nitrate reduction to ammonium (DNRA) and denitrification in biofilters. CHEMOSPHERE 2021; 280:130917. [PMID: 34162105 DOI: 10.1016/j.chemosphere.2021.130917] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 05/03/2021] [Accepted: 05/13/2021] [Indexed: 06/13/2023]
Abstract
The effect of organic carbon (OC) quality and quantity on switch between dissimilatory nitrate reduction to ammonium (DNRA) and denitrification (DEN) was studied in biofilter systems. High OC in matrix could promote significantly nitrate (NO3--N) removal due to the reinforce of DEN. Sodium acetate (SA) addition in influent further fueled NO3--N removal in groups with low OC in matrix but increased ammonium (NH4+-N) and nitrite (NO2--N) accumulation in groups with high OC in matrix. This indicated that high OC combined different species, facilitated the DNRA over DEN. Compared to bagasse, corncob was the better suitable OC source in matrix for DEN due to slow and continuous release of OC. Hence, in order to promote NO3--N removal and decline NH4+-N accumulation in biofilters, it is very important to screen suitable OC source (mixed utilization of multiple C sources is recommended) and regulate its dosage (below 80 mg L-1).
Collapse
Affiliation(s)
- Feng Sun
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, PR China.
| | - Qinghui Deng
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, PR China; University of Chinese Academy of Sciences, Beijing, 100039, PR China.
| | - Xiaowen Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, PR China; University of Chinese Academy of Sciences, Beijing, 100039, PR China.
| | | | - Xufa Ma
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, PR China.
| | - Xiuyun Cao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, PR China.
| | - Yiyong Zhou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, PR China.
| | - Chunlei Song
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, PR China.
| |
Collapse
|
4
|
Guo Z, Boeing WJ, Xu Y, Yan C, Faghihinia M, Liu D. Revisiting seasonal dynamics of total nitrogen in reservoirs with a systematic framework for mining data from existing publications. WATER RESEARCH 2021; 201:117380. [PMID: 34198201 DOI: 10.1016/j.watres.2021.117380] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/17/2021] [Accepted: 06/18/2021] [Indexed: 06/13/2023]
Abstract
Investigation of seasonal variations of water quality parameters is essential for understanding the mechanisms of structural changes in aquatic ecosystems and their pollution control. Despite the ongoing rise in scientific production on spatiotemporal distribution characteristics of water quality parameters, such as total nitrogen (TN) in reservoirs, attempts to use published data and incorporate them into a large-scale comparison and trends analyses are lacking. Here, we propose a framework of Data extraction, Data grouping and Statistical analysis (DDS) and illustrate application of this DDS framework with the example of TN in reservoirs. Among 1722 publications related to TN in reservoirs, 58 TN time-series data from 19 reservoirs met the analysis requirements and were extracted using the DDS framework. We performed statistical analysis on these time-series data using Dynamic Time Warping (DTW) combined with agglomerative hierarchical clustering as well as Generalized Additive Models for Location, Scale, and Shape (GAMLSS). Three patterns of seasonal TN dynamics were identified. In Pattern V-Sum, TN concentrations change in a "V" shape, dropping to its lowest value in summer; in Pattern P-Sum, TN increases in late summer/early fall before decreasing again; and in Pattern P-Spr, TN peaks in spring. Identified patterns were driven by phytoplankton growth and precipitation (Pattern V-Sum), nitrate wet deposition and agricultural runoff (Pattern P-Sum), and anthropogenic discharges (Pattern P-Spr). Application of the DDS framework has identified a key bottleneck in assessing the dynamics of TN - low data accessibility and availability. Providing an easily accessible data sharing platform and increasing the accessibility and availability of raw data for research will facilitate improvements and expand the applicability of the DDS framework. Identification of additional spatiotemporal patterns of water quality parameters can provide new insights for more comprehensive pollution control and management of aquatic ecosystems.
Collapse
Affiliation(s)
- Zhaofeng Guo
- Key Laboratory of Urban Environment and Health, Fujian Key Laboratory of Watershed Ecology, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wiebke J Boeing
- Department of Fish, Wildlife & Conservation Ecology, New Mexico State University, Las Cruces, NM 88003, USA
| | - Yaoyang Xu
- Key Laboratory of Urban Environment and Health, Fujian Key Laboratory of Watershed Ecology, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control, Ningbo Urban Environment Observation and Research Station, Chinese Academy of Sciences, Ningbo 315830, China.
| | - Changzhou Yan
- Key Laboratory of Urban Environment and Health, Fujian Key Laboratory of Watershed Ecology, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Maede Faghihinia
- Key Laboratory of Urban Environment and Health, Fujian Key Laboratory of Watershed Ecology, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control, Ningbo Urban Environment Observation and Research Station, Chinese Academy of Sciences, Ningbo 315830, China
| | - Dong Liu
- Key Laboratory of Urban Environment and Health, Fujian Key Laboratory of Watershed Ecology, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
5
|
Deng O, Chen Y, Lan T, Zhang S, Gao X, Zhou W, Ou D, Hu Y, Luo L. Contribution of atmospheric N deposition to riverine N load in a forest-dominated watershed through field monitoring for three years. CHEMOSPHERE 2021; 266:128951. [PMID: 33218727 DOI: 10.1016/j.chemosphere.2020.128951] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/09/2020] [Accepted: 11/11/2020] [Indexed: 06/11/2023]
Abstract
Increased atmospheric nitrogen (N) deposition significantly impacts N cycling in freshwater ecosystems. Relative to lakes, the importance of N deposition in riverine N load is less studied. Thus, this study monitored N deposition and riverine N load for three years and then used the export coefficient model to explore N deposition's contribution to riverine N load in a forest-dominated watershed. It is found that the annual export of total N (TN) deposition could explain 17.4%-19.2% of riverine TN load. The contribution of TN deposition to riverine TN load was significantly higher (P < 0.05) during the crop production period (recorded as CPP, lasting from June to September, 22.7%) than the non-crop production period (Non-CPP, 13.8%). The application of chemical fertilizer and manure and the high precipitation were assumed as the primary reason for the increased N deposition and increased riverine TN load during CPP. This study shows that inland plain agriculture practices might considerably influence the nearby forest-dominated watershed, and it is necessary to develop sustainable agriculture programs for reducing riverine N load.
Collapse
Affiliation(s)
- Ouping Deng
- College of Resources, Sichuan Agricultural University, Chengdu, 611130, PR China
| | - Yuanyuan Chen
- College of Resources, Sichuan Agricultural University, Chengdu, 611130, PR China
| | - Ting Lan
- College of Resources, Sichuan Agricultural University, Chengdu, 611130, PR China
| | - Shirong Zhang
- College of Environmental Sciences, Sichuan Agricultural University, Chengdu, 611130, PR China
| | - Xuesong Gao
- College of Resources, Sichuan Agricultural University, Chengdu, 611130, PR China
| | - Wei Zhou
- College of Resources, Sichuan Agricultural University, Chengdu, 611130, PR China
| | - Dinghua Ou
- College of Resources, Sichuan Agricultural University, Chengdu, 611130, PR China
| | - Yufu Hu
- College of Resources, Sichuan Agricultural University, Chengdu, 611130, PR China
| | - Ling Luo
- College of Resources, Sichuan Agricultural University, Chengdu, 611130, PR China; College of Environmental Sciences, Sichuan Agricultural University, Chengdu, 611130, PR China.
| |
Collapse
|
6
|
Rainwater Chemistry Reveals Air Pollution in a Karst Forest: Temporal Variations, Source Apportionment, and Implications for the Forest. ATMOSPHERE 2020. [DOI: 10.3390/atmos11121315] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Temporal rainwater chemistry was used to reveal air pollution in the Maolan National Karst Forest Park (MNKFP), which is representative of the typical karst forest region of southwest China (SW China). The rainwater ions’ sources, variations, trends, and potential environmental effects were investigated from 2007 to 2010 and from 2013 to 2014. Based on the analysis of the temporal ionic concentrations of rainwater in the MNKFP, significant variations of ions were observed, including in NH4+ (9.7~266.6 μeq L−1) and SO42− (14.5~1396.4 μeq L−1), which were mainly controlled by variations in the source and rainfall amount; a decreased trend of rainwater pH was also observed. Accordingly, NH4+, Ca2+, SO42−, and Cl− were regarded as the most dominant ions. Typical ionic ratios and positive matrix factorization (PMF) model-based source apportionment suggested that anthropogenic inputs (coal combustion, industrial, traffic, and agricultural emissions) contributed 51% of F−, 93% of NO3−, 62% of SO42−, and 87% of NH4+, while the natural sources (crustal dust and sea salt) were the main sources of Cl− (74%), Na+ (82%), K+ (79%), Mg2+ (94%), and Ca2+ (93%). In combination with the reducing neutralization trend of temporal rainwater observed in the MNKFP and the potential effect of rainwater ion deposition on karst forests, more detailed monitoring of the rainfall-related deposition process is required for a better understanding of its potential environmental effects on the Earth’s surface.
Collapse
|
7
|
Zeng J, Yue FJ, Li SL, Wang ZJ, Wu Q, Qin CQ, Yan ZL. Determining rainwater chemistry to reveal alkaline rain trend in Southwest China: Evidence from a frequent-rainy karst area with extensive agricultural production. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 266:115166. [PMID: 32682186 DOI: 10.1016/j.envpol.2020.115166] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 07/01/2020] [Accepted: 07/01/2020] [Indexed: 06/11/2023]
Abstract
Rainwater chemistry plays an important role in the earth-surficial ecosystem, but studies on rainwater chemical composition of karst agro-ecosystem are rare. To explore the rainwater alkalization and the provenance of components responsible for neutralization, two-years chemical monitoring of rainwater was carried out in a karst agricultural catchment in Southwest China. The main findings suggest that SO42-, NO3-, Ca2+, and NH4+ are the principal ions. All the ionic contents show distinctly seasonal variation (highest in winter) in response to variations in seasonal precipitation because the rain-scour process can efficiently remove atmospheric materials. Source identification indicates that Cl- and Na+ are mainly derived from marine input whereas SO42- and NO3- are controlled by anthropogenic emission, in particular, fixed emission sources. The source of NH4+ is attributed to intense agricultural production, while Ca2+ and Mg2+ are mainly derived from calcite dissolution. The rainwater alkalization caused by the seasonal acid neutralization (via basic components, Ca2+ and NH4+) is beneficial to crop growth but also reflect agricultural overfertilization. Sulfur controlled the total wet acid deposition (68%-94%) and could be a potential agent of weathering.
Collapse
Affiliation(s)
- Jie Zeng
- Institute of Earth Sciences, China University of Geosciences (Beijing), Beijing, 100083, China
| | - Fu-Jun Yue
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, China; Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin, 300072, China; Puding Karst Ecosystem Research Station, Institute of Geochemistry, Chinese Academy of Sciences, Anshun, 562100, China.
| | - Si-Liang Li
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, China; Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin, 300072, China; Puding Karst Ecosystem Research Station, Institute of Geochemistry, Chinese Academy of Sciences, Anshun, 562100, China
| | - Zhong-Jun Wang
- Puding Karst Ecosystem Research Station, Institute of Geochemistry, Chinese Academy of Sciences, Anshun, 562100, China
| | - Qixin Wu
- Key Laboratory of Karst Environment and Geohazard, Ministry of Land and Resources, Guizhou University, Guiyang, 550025, China
| | - Cai-Qing Qin
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Ze-Long Yan
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, China
| |
Collapse
|
8
|
Zhang L, Tian M, Peng C, Fu C, Li T, Chen Y, Qiu Y, Huang Y, Wang H, Li Z, Yang F. Nitrogen wet deposition in the Three Gorges Reservoir area: Characteristics, fluxes, and contributions to the aquatic environment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 738:140309. [PMID: 32806348 DOI: 10.1016/j.scitotenv.2020.140309] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 06/15/2020] [Accepted: 06/15/2020] [Indexed: 06/11/2023]
Abstract
Measurements of nitrate nitrogen (NO3--N), ammonia nitrogen (NH4+-N), and dissolved organic nitrogen (DON) in precipitation were conducted at six different sites in the hinterland of the Three Gorges Reservoir (TGR) area from January 2016 to December 2017. The characteristics and the sources of nitrogen (N) species were identified. N flux of wet deposition in the hinterland of the TGR area were 13.56 ± 2.95 kg N ha-1 yr-1, of which the proportions of NO3--N, NH4+-N and DON were 60.9%, 25.1% and 14.0%, respectively. N flux in urban area was significantly higher than those in suburban, agricultural, and wetland areas. Industrial activities, biomass burning, and secondary transformation were the main contributors of N in urban area. In agricultural area, biomass burning, crustal, and manure were main sources of N. In suburban area, mixed emissions from industry, agriculture, and crustal sources were primary contributors of N. For wetlands, the major contributions were from industrial sector and biomass burning. Additional, analysis of regional distribution of dissolved N deposition in the TGR area was conducted by combining current study data and previously published data between 2000 and 2017. N flux of wet deposition in the entire TGR area ranged from 12.17 to 51.93 kg N ha-1 yr-1, with an average of 26.81 kg N ha-1 yr-1. Regional N distribution was greatest in the tail region, followed by the head region, and then the hinterland in the TGR area. The amount of N entering the TGR directly through atmospheric wet deposition was 2906 t yr-1, accounting for 2.1% of the total N inputs. N load from wet deposition had exceeded the critical loads from that of the water, forest, and even some farmland ecosystems in the TGR area. Decreasing NH3 emissions from agricultural activities is the key to alleviate the regional N deposition.
Collapse
Affiliation(s)
- Liuyi Zhang
- Chongqing Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir Area, Chongqing Three Gorges University, Wanzhou 404000, China; CAS Key Laboratory of Reservoir Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - Mi Tian
- College of Environmental and Ecology, Chongqing University, Chongqing 400044, China
| | - Chao Peng
- CAS Key Laboratory of Reservoir Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - Chuan Fu
- Chongqing Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir Area, Chongqing Three Gorges University, Wanzhou 404000, China
| | - Tingzhen Li
- Chongqing Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir Area, Chongqing Three Gorges University, Wanzhou 404000, China.
| | - Yang Chen
- CAS Key Laboratory of Reservoir Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - Yang Qiu
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Yimin Huang
- Chongqing Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir Area, Chongqing Three Gorges University, Wanzhou 404000, China
| | - Huanbo Wang
- CAS Key Laboratory of Reservoir Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China; College of Environmental and Ecology, Chongqing University, Chongqing 400044, China
| | - Zhe Li
- CAS Key Laboratory of Reservoir Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - Fumo Yang
- Chongqing Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir Area, Chongqing Three Gorges University, Wanzhou 404000, China; CAS Key Laboratory of Reservoir Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China; College of Environmental and Ecology, Chongqing University, Chongqing 400044, China; College of Architecture and Environment, Sichuan University, Chengdu 610065, China; National Engineering Research Center for Flue Gas Desulfurization, Department of Environmental Science and Engineering, Sichuan University, Chengdu 610065, China.
| |
Collapse
|
9
|
Measurement of Total Nitrogen Concentration in Surface Water Using Hyperspectral Band Observation Method. WATER 2020. [DOI: 10.3390/w12071842] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Nitrogen overload is one of the main reasons for the deterioration of surface water quality. Hence, monitoring nitrogen loadings is vital in maintaining good surface water quality. Increasingly, the use of spectral reflectance to monitor nitrogen concentration in water has shown potentials, but it poses some problems. Therefore, it is necessary to explore new methods of quantitative monitoring of nitrogen concentration in surface water. In this paper, hyperspectral data from surface water in the Ebinur Lake watershed are used to select sensitive bands using spectral transformation, the spectral index, and a coupling of these two methods. The particle swarm optimization support vector machine (PSO-SVM) model, constructed on the basis of sensitive bands, is used quantitatively to estimate the total nitrogen concentration in surface water and subsequently to verify its accuracy. The results show that the bands near 680, 850, and 940 nm can be used as sensitive bands for estimation of the total nitrogen concentration of surface water in arid regions. Compared with the best estimation models constructed by sensitive bands selected using the spectral transformation or the spectral index alone, the best model based on the coupling of these two measures is more accurate (R2 = 0.604, Root Mean Square Error (RMSE) = 1.61 mg/L, Residual Prediction Deviation (RPD) = 2.002). This coupling method leads to a robust, accurate, and strong predictability model, and can contribute to improved quantitative estimation of water quality indexes of rivers in arid regions.
Collapse
|
10
|
Gao Y, Zhou F, Ciais P, Miao C, Yang T, Jia Y, Zhou X, Klaus BB, Yang T, Yu G. Human activities aggravate nitrogen-deposition pollution to inland water over China. Natl Sci Rev 2020; 7:430-440. [PMID: 34692058 PMCID: PMC8288964 DOI: 10.1093/nsr/nwz073] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 05/03/2019] [Accepted: 06/21/2019] [Indexed: 11/21/2022] Open
Abstract
In the past three decades, China has built more than 87 000 dams with a storage capacity of ≈6560 km3 and the total surface area of inland water has increased by 6672 km2. Leaching of N from fertilized soils to rivers is the main source of N pollution in China, but the exposure of a growing inland water area to direct atmospheric N deposition and N leaching caused by N deposition on the terrestrial ecosystem, together with increased N deposition and decreased N flow, also tends to raise N concentrations in most inland waters. The contribution of this previously ignored source of N deposition to freshwaters is estimated in this study, as well as mitigation strategies. The results show that the annual amounts of N depositions ranged from 4.9 to 16.6 kg · ha-1 · yr-1 in the 1990s to exceeding 20 kg · ha-1 · yr-1 in the 2010s over most of regions in China, so the total mass of ΔN (the net contribution of N deposition to the increase in N concentration) for lakes, rivers and reservoirs change from 122.26 Gg N · yr-1 in the 1990s to 237.75 Gg N · yr-1 in the 2010s. It is suggested that reducing the N deposition from various sources, shortening the water-retention time in dams and decreasing the degree of regulation for rivers are three main measures for preventing a continuous increase in the N-deposition pollution to inland water in China.
Collapse
Affiliation(s)
- Yang Gao
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| | - Feng Zhou
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Philippe Ciais
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
- Laboratoire des Sciences du Climat et de l’Environnement, CEA CNRS UVSQ, Gif-sur-Yvette 91191, France
| | - Chiyuan Miao
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China
| | - Tao Yang
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Center for Global Change and Water Cycle, Hohai University, Nanjing 210098, China
| | - Yanlong Jia
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Xudong Zhou
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Center for Global Change and Water Cycle, Hohai University, Nanjing 210098, China
| | - Butterbach-Bahl Klaus
- Institute for Meteorology and Climate Research, Atmospheric Environmental Research, Karlsruhe Institute of Technology, 82467 Garmisch-Partenkirchen, Germany
| | - Tiantian Yang
- Department of Civil and Environmental Engineering, University of California, Irvine, CA 92697, USA
| | - Guirui Yu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| |
Collapse
|
11
|
Li J, Yang C, Liu X, Ji H, Shao X. Soil aggregate size influences the impact of inorganic nitrogen deposition on soil nitrification in an alpine meadow of the Qinghai-Tibet Plateau. PeerJ 2020; 8:e8230. [PMID: 31938575 PMCID: PMC6953337 DOI: 10.7717/peerj.8230] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 11/18/2019] [Indexed: 11/20/2022] Open
Abstract
Background Ammonium (NH4 +) and nitrate (NO3 -) are two inorganic forms of nitrogen (N) that are deposited from the atmosphere into soil systems. As the substrate and product of soil nitrification, these two forms of inorganic nitrogen will affect or be affected by the soil net nitrification rate (Nr). Our knowledge regarding soil nitrification is mainly derived from studies with bulk soil. However, soil is composed of different aggregate fractions, which may have an important impact on Nr. Methods In 2017, we collected soil samples from an alpine meadow of the Qinghai-Tibet Plateau and separated them into four soil aggregates (2-4, 1-2, 0.25-1, and <0.25 mm) using the dry sieving method. The four soil aggregate sizes amended with the 2 N deposition forms (NH4 +-N and NO3 --N) were then incubated at 25 °C for 28 days, and the soil aggregates for each treatment were collected on day 0, 7, 14, 21, and 28 to determine the NO3 --N concentration. The soil Nr and contribution of soil aggregates to the nitrification rate in the bulk soil were calculated. Results There were differences in the physicochemical properties of the soil aggregates. The addition of N and aggregate size had strong effects on soil Nr, which were significantly increased under high levels of NH4 + addition across all soil aggregates. The Nr during the 4 week incubation period differed among aggregate sizes. Nr in the 2-4 mm aggregates was higher than in the other aggregates, which was correlated with the maximum values of the soil porosity observed in the 2-4 mm aggregates. Furthermore, almost half of the soil was composed of aggregates of <0.25 mm, indicating that the <0.25 mm aggregates made a higher contribution to the nitrification rate in the bulk soil than the other aggregates, even though these aggregates had a lower nitrification ability. Overall, our study revealed that the soil nitrification rate was influenced by both the N addition and soil aggregates, and that the 2-4 mm aggregates had a dominant effect on the response of soil N transformation processes to future nitrogen deposition in the alpine meadow.
Collapse
Affiliation(s)
- Jingjing Li
- College of Grassland Science and Technology, China Agricultural University, Beijing, China
| | - Chao Yang
- Grassland Agri-Husbandry Research Center, College of Grassland Science, Qingdao Agricultural University, Qingdao, China
| | - Xiaoli Liu
- College of Grassland Science and Technology, China Agricultural University, Beijing, China
| | - Hanzhong Ji
- Institute of Haibei Tibetan Autonomous Prefecture Animal Husbandry and Veterinary Science, Xining, China
| | - Xinqing Shao
- College of Grassland Science and Technology, China Agricultural University, Beijing, China.,Technical Platform for Adaptive Management of Livestock System in Alpine Grassland, Xining, China.,Key Laboratory of Restoration Ecology of Cold Area in Qinghai Province, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
| |
Collapse
|
12
|
Zhang X, Lin C, Zhou X, Lei K, Guo B, Cao Y, Lu S, Liu X, He M. Concentrations, fluxes, and potential sources of nitrogen and phosphorus species in atmospheric wet deposition of the Lake Qinghai Watershed, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 682:523-531. [PMID: 31129540 DOI: 10.1016/j.scitotenv.2019.05.224] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 04/08/2019] [Accepted: 05/15/2019] [Indexed: 06/09/2023]
Abstract
Plateau lakes are typically dystrophic and are sensitive to small changes in nutrient deposition. With this assumption, we investigated the concentrations, fluxes, and sources of nitrogen (N) and phosphorus (P) in the atmospheric wet deposition (AWD) of the Lake Qinghai Watershed (LQW), which is the largest inland lake in China, for one year from October 2017 to September 2018. The results showed that the annual volume-weighted mean (VWM) concentrations (mg L-1) in the AWD were 1.97 for NH4+-N, 0.55 for NO3--N, 0.04 for NO2--N, 0.77 for dissolved organic N (DON), 3.33 for total dissolved N (TDN), 0.30 for dissolved inorganic P (DIP), 0.07 for dissolved organic P (DOP), 0.36 for total dissolved P (TDP), and 0.99 for reactive sulfur (SO42--S). The annual AWD fluxes of TDN and TDP were 16.82 and 1.86 kg ha-1 yr-1, respectively. Strong dilution effects in the wet season, a long residency time of nutrient-rich aerosols in the dry season, strong ammonia volatilization in the wet and warm seasons, and moisture sources dominated the seasonal or monthly changing characteristics of N and P concentrations in the AWD, including high in the wet season and low in the dry season for NH4+-N, low in the wet season and high in the dry season for NO3--N, and generally increasing from April to September for DIP and DOP. Precipitation quantity dominated the monthly changes in the N and P fluxes of the AWD, which gradually increased from April to August and then decreased in September. N and P in the AWD mostly originated from anthropogenic sources. High ammonia volatilization from local intense animal husbandry, alkaline soils and lakes led to a relatively high NH4+-N concentration compared with other sites of the Qinghai-Tibet Plateau, China, and in the world. The N/P molar ratio in the precipitation was higher than 16, which might have effect on the aquatic ecosystems of Lake Qinghai. Ammonia volatilization fluxes and atmospheric dry deposition fluxes of N and P should be further studied to completely understand the geochemical cycles of N and P in the LQW.
Collapse
Affiliation(s)
- Xuan Zhang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Chunye Lin
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China.
| | - Xueli Zhou
- Tiebujia Grassland Improvement Experiment Station, Gonghe 813000, China
| | - Kai Lei
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Bobo Guo
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Yuanxin Cao
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Shuang Lu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Xitao Liu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Mengchang He
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| |
Collapse
|
13
|
Wang W, Xu W, Wen Z, Wang D, Wang S, Zhang Z, Zhao Y, Liu X. Characteristics of Atmospheric Reactive Nitrogen Deposition in Nyingchi City. Sci Rep 2019; 9:4645. [PMID: 30874577 PMCID: PMC6420578 DOI: 10.1038/s41598-019-39855-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 02/01/2019] [Indexed: 11/09/2022] Open
Abstract
Atmospheric reactive nitrogen (N) deposition has been proven to be an important nutrient input from external environments to forest ecosystems. However, the magnitude of atmospheric N deposition in the Tibetan region of China is not well known. In this study, multi-year (between 2005 and 2016) measurements of dry and wet N deposition were carried out in Nyingchi (NC) city, southeastern Tibet. Bulk deposition was collected by the rain gauge method; dry deposition was calculated by the inferential method, namely, multiplying ambient N concentrations by dry deposition velocity (Vd) of the N species. During the entire period, annual bulk and dry N deposition fluxes averaged 2.19 and 1.85 kg N ha-1 yr-1, respectively. Total N deposition fluxes (the sum of reduced and oxidized N species in dry and bulk deposition) showed an obvious increasing trend, especially for oxidized N species. Both bulk and dry N deposition showed a consistent seasonal pattern, with the highest fluxes in summer and the lowest in winter. Our findings suggest that N deposition to the urban environment in southeast Tibet has recently shifted from ammonium-dominated to nitrate-dominated conditions.
Collapse
Affiliation(s)
- Wei Wang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China.,Xizang Agriculture and Animal Husbandry University, Nyingchi, Tibet, 860000, China
| | - Wen Xu
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Zhang Wen
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Dandan Wang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Sen Wang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Zhiwei Zhang
- Xizang Agriculture and Animal Husbandry University, Nyingchi, Tibet, 860000, China
| | - Yuanhong Zhao
- Laboratory for Climate and Ocean-Atmosphere Sciences, Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing, 100871, China
| | - Xuejun Liu
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China.
| |
Collapse
|
14
|
Hao Z, Zhang X, Gao Y, Xu Z, Yang F, Wen X, Wang Y. Nitrogen source track and associated isotopic dynamic characteristic in a complex ecosystem: A case study of a subtropical watershed, China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 236:177-187. [PMID: 29414338 DOI: 10.1016/j.envpol.2018.01.078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 01/18/2018] [Accepted: 01/22/2018] [Indexed: 06/08/2023]
Abstract
By identifying the main sources of nitrate (NO3-) can obtain useful information to support the management of NO3- pollution, particularly in subtropical catchments with shallow drinking water wells. This study used water chemistry and dual stable isotopes δ15N and δ18O methods to assess seasonal and spatial variations of NO3- in precipitation, surface water, and groundwater in an agricultural and forest subtropical catchment in Jiangxi Province, China. The maximum concentrations of nitrate-nitrogen (NO3--N) and ammonium-nitrogen (NH4+-N) were 10.4 and 10.8 mg L-1in samples collected from 221 rainfall events from 2011 to 2013. About 4.4% and 12.3% NH4+-N concentrations of surface water and groundwater exceeded the thresholds of 1.0 and 0.2 mg L-1. The NO3--N concentrations in surface water were closely correlated with NH4+-N concentrations in surface water and groundwater (r = -0.71 and r = -0.71, P < 0.05). The concentrations of NH4+-N and NO3--N were significantly higher in a fishery pond and nearby drinking wells than in other monitoring points. Annual exports of NO3--N and NH4+-N were 4.06 × 104 and 8.14 × 103 kg yr-1, respectively and NO3--N is the main form of N loss. The δ15N values ranged from 0‰ to 20‰ in surface water and groundwater, and the δ18O values ranged from 0‰ to 15‰ and 1‰-13‰, respectively. Dual stable isotope natural abundance distribution and water chemistry [NO3-]/[Cl-] molar ratio information suggested that manure and sewage and soil N were the main sources of NO3- in surface water and manure and sewage in groundwater in summer and winter. In spring, water occurred denitrification and ammonium fertilizer, manure and sewage were the main sources of NO3- in surface water and groundwater which sampling points were closer residential area and fish ponds than paddy field and local farmers used more Manure. Manure applications should be reasonable around drinking water wells to protect the drinking water quality.
Collapse
Affiliation(s)
- Zhuo Hao
- Key Laboratory of Ecosystem Network Observation and Modeling, 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
| | - Xinyu Zhang
- Key Laboratory of Ecosystem Network Observation and Modeling, 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.
| | - Yang Gao
- Key Laboratory of Ecosystem Network Observation and Modeling, 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.
| | - Zhiwei Xu
- College of Geographical Sciences, Northeast Normal University, Changchun, 130024, China
| | - Fengting Yang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Xuefa Wen
- Key Laboratory of Ecosystem Network Observation and Modeling, 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
| | - Yueming Wang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| |
Collapse
|
15
|
Gao Y, Hao Z, Yang T, He N, Wen X, Yu G. Effects of atmospheric reactive phosphorus deposition on phosphorus transport in a subtropical watershed: A Chinese case study. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2017; 226:69-78. [PMID: 28410509 DOI: 10.1016/j.envpol.2017.03.067] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 03/27/2017] [Accepted: 03/27/2017] [Indexed: 06/07/2023]
Abstract
Atmospheric phosphorus (P) deposition is not only an important external macronutrient source for aquatic ecosystems but also a major cause of high export coefficient (EC) values. However, there are limited numbers of studies in the literature that focus on estimating the deposition flux of reactive P (Pr). The aim of this study is to estimate the Pr deposition on the Xiangxi River watershed, and therefore, provide a comprehensive understanding about the Pr deposition on subtropical watersheds in China. Results have shown that maximal Pr deposition fluxes reached 12 kg km-2 in our selected subtropical watershed. Furthermore, we found out the particulate phosphorus (PP) were dominating the total Pr deposition in the Xiangxi River watershed. According to our experiments, certain forms of Pr deposition were associated with high correlation coefficients with respect to the variation of rainfall intensity. Results also demonstrated that the dissolved organic phosphorus (DOP) and soluble reactive phosphorus (SRP) via wet deposition had large influences on the DOP and SRP concentrations in runoff, while the PO4-P and PP via wet deposition only affected PO4-P and PP loads through runoff discharge. Our experiments also shown that most parts of the Pr in runoff water was derived from rainfall and its magnitudes varied with land types. Results suggested that during the dry season, the Pr wet deposition not only was an important source for the Pr transport driven by runoff, but also was one of the most important influencing factors that dominated the Pr transport in subtropical watersheds.
Collapse
Affiliation(s)
- Yang Gao
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, PR China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, PR China.
| | - Zhuo Hao
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, PR China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, PR China
| | - Tiantian Yang
- Department of Civil and Environmental Engineering, University of California, Irvine, CA 92697, United States
| | - Nianpeng He
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, PR China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, PR China
| | - Xuefa Wen
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, PR China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, PR China
| | - Guirui Yu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, PR China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, PR China
| |
Collapse
|