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Bao Y, Sun M, Wang Y, Hu M, Hu P, Wu L, Huang W, Li S, Wen J, Wang Z, Zhang Q, Wu N. Nitrate transformation and source tracking of Yarlung Tsangpo River using a multi-tracer approach combined with Bayesian stable isotope mixing model. ENVIRONMENTAL RESEARCH 2024; 252:118925. [PMID: 38615795 DOI: 10.1016/j.envres.2024.118925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 04/01/2024] [Accepted: 04/11/2024] [Indexed: 04/16/2024]
Abstract
Excessive levels of nitrate nitrogen (NO3--N) could lead to ecological issues, particularly in the Yarlung Tsangpo River (YTR) region located on the Qinghai Tibet Plateau. Therefore, it is crucial to understand the fate and sources of nitrogen to facilitate pollution mitigation efforts. Herein, multiple isotopes and source resolution models were applied to analyze key transformation processes and quantify the sources of NO3-. The δ15N-NO3- and δ18O-NO3- isotopic compositions in the YTR varied between 1.23‰ and 13.64‰ and -7.88‰-11.19‰, respectively. The NO3--N concentrations varied from 0.08 to 0.86 mg/L in the dry season and 0.20-1.19 mg/L during the wet season. Nitrification remained the primary process for nitrogen transformation in both seasons. However, the wet season had a widespread effect on increasing nitrate levels, while denitrification had a limited ability to reduce nitrate. The elevated nitrate concentrations during the flood season were caused by increased release of NO3- from manure & sewage (M&S) and chemical fertilizers (CF). Future endeavors should prioritize enhancing management strategies to improve the utilization efficiency of CF and hinder the direct entry of untreated sewage into the water system.
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Affiliation(s)
- Yufei Bao
- State Key Laboratory of Watershed Water Cycle Simulation and Regulation, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China; Department of Water Ecology and Environment, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China.
| | - Meng Sun
- State Key Laboratory of Watershed Water Cycle Simulation and Regulation, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China; Department of Water Ecology and Environment, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China
| | - Yuchun Wang
- State Key Laboratory of Watershed Water Cycle Simulation and Regulation, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China; Department of Water Ecology and Environment, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China.
| | - Mingming Hu
- State Key Laboratory of Watershed Water Cycle Simulation and Regulation, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China; Department of Water Ecology and Environment, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China
| | - Peng Hu
- State Key Laboratory of Watershed Water Cycle Simulation and Regulation, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China
| | - Leixiang Wu
- State Key Laboratory of Watershed Water Cycle Simulation and Regulation, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China; Department of Water Ecology and Environment, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China
| | - Wei Huang
- State Key Laboratory of Watershed Water Cycle Simulation and Regulation, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China; Department of Water Ecology and Environment, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China
| | - Shanze Li
- State Key Laboratory of Watershed Water Cycle Simulation and Regulation, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China; Department of Water Ecology and Environment, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China
| | - Jie Wen
- State Key Laboratory of Watershed Water Cycle Simulation and Regulation, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China; Department of Water Ecology and Environment, China Institute of Water Resources and Hydropower Research, Beijing, 100038, China
| | - ZhongJun Wang
- School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng, 224051, China
| | - Qian Zhang
- School of Civil Engineering & Architecture, Wuhan University of Technology, Wuhan, 430070, China
| | - Nanping Wu
- School of Civil Engineering & Architecture, Wuhan University of Technology, Wuhan, 430070, China
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Mingyue L, Xuejun S, Shengnan L, Jie W, Zijian L, Qianggong Z. Hydrochemistry dynamics in a glacierized headwater catchment of Lhasa River, Tibetan Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 919:170810. [PMID: 38336076 DOI: 10.1016/j.scitotenv.2024.170810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 01/26/2024] [Accepted: 02/06/2024] [Indexed: 02/12/2024]
Abstract
Mountain glaciers are essential for supplying water resources that sustain downstream communities and livelihoods, yet the hydrogeochemical dynamics at glacier terminals and the impact of glacier retreat on downstream water chemistry are not fully understood. This study addresses this by conducting comprehensive observations and analysis of water chemistry at refined spatial and temporal resolutions in the Lhasa River Valley Glacier No. 1 (LRVG-1) catchment, a vital source of drinking and irrigation water for the local population on the Tibetan Plateau. Our findings reveal a weakly alkaline water environment within this glacierized basin, with HCO3- and Ca2+ as the dominant anions and cations, respectively, resulting in a hydrochemical pattern classified as HCO3--Ca2+ type. Solute concentrations increase along the glacier meltwater pathway, influenced by water-rock interaction, dilution, and diverse sources. The cations are predominantly from carbonate weathering, constituting 72.86 % of the total cations, followed by sulfide oxidation (11.08 %), glacier meltwater inputs (8.13 %), and silicate weathering (7.93 %). The contribution of cations from glacier meltwater diminishes as they travel along the glacier meltwater flow pathway. Our study indicates the localized yet significant impact of glacier meltwater on hydrochemistry, particularly in the vicinity of the glacier terminus. We recommend considering glacial meltwater and the entire glacier watershed as a continuum, essential for understanding the cumulative effects of glacier melt and human activities on water quality. This perspective is crucial for predicting future river chemistry trajectories in high-mountain basins and informing policy-making for water quality conservation across the Tibetan Plateau.
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Affiliation(s)
- Li Mingyue
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Sun Xuejun
- School of Environmental and Resource Sciences, Shanxi University, Taiyuan 030006, China
| | - Li Shengnan
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wang Jie
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lu Zijian
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhang Qianggong
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Lhasa Earth System Multi-Dimension Observatory Network (LEMON), Lhasa 850000, China.
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Yang D, Yao T, Wu G, Zhao H, Zhu M, Deji, Qu D, Shi Y. Identifying the natural and agricultural impacts on the glaciochemistry of the Aru ice core on the northwestern Tibetan Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167501. [PMID: 37783433 DOI: 10.1016/j.scitotenv.2023.167501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 09/28/2023] [Accepted: 09/28/2023] [Indexed: 10/04/2023]
Abstract
Glaciochemical data sourced from ice cores in polar regions and the Alps have been extensively examined. However, quantitative studies on glaciochemical records of the Tibetan Plateau (TP) are scarce. To address this, we investigated annual variations in the major soluble ions (Ca2+, Mg2+, Na+, K+, NH4+, Cl-, NO3-, and SO42-) in the Aru ice core on the northwestern TP from 1850 to 2016. Applying a positive matrix factorization model, the sources of the major soluble ions and three factors to evaluate natural and agricultural impacts were identified. Factor 1, crustal dust with high loadings of Mg2+ (81.9 %) and Ca2+ (68.7 %), significantly positively correlated with wind speed and significantly negatively correlated with δ18O and net accumulation recorded by the ice core, suggesting that strong winds contributed to crustal dust transport from arid and semi-arid regions of Central Asia and deposition in the Aru glacier. However, relatively warm and wet climate prevented the transport of crustal dust. Factor 2 comprised salt lakes with high dominant loadings of Na+ (75.3 %), SO42- (64.1 %), Cl- (60.8 %), NO3- (52.2 %), and K+ (49.4 %). Declining lake water levels exposed salt lake minerals, which were carried to glaciers under the dynamic conditions of strong winds, whereas warming resulted in an expansion of glacial meltwater and lake water volume, which decreased the contribution of salt lake sediments. Therefore, the contribution of salt lake deposition decreased. Factor 3 was agricultural sources with a high loading of NH4+ (82 %), whose trend aligned closely with the population number and N productions from agricultural sources in South and Central Asia, suggesting that NH3 emissions from agricultural practices are a critical contributor to Factor 3. This study quantified the proportional contribution of natural and agricultural sources to glaciochemical composition, advancing our understanding of glaciochemical records in ice cores from source recognition to quantification.
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Affiliation(s)
- Dandan Yang
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Science, Beijing 100049, China
| | - Tandong Yao
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Center for the Pan-Third Pole Environment, Lanzhou University, Lanzhou, China.
| | - Guangjian Wu
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Huabiao Zhao
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Meilin Zhu
- Center for the Pan-Third Pole Environment, Lanzhou University, Lanzhou, China
| | - Deji
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Dongmei Qu
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Yanyun Shi
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
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