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Kang L, Zhu M, Zhu G, Xu H, Zou W, Xiao M, Guo C, Zhang Y, Qin B. Decreasing denitrification rates poses a challenge to further decline of nitrogen concentration in Lake Taihu, China. WATER RESEARCH 2024; 256:121565. [PMID: 38581985 DOI: 10.1016/j.watres.2024.121565] [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: 01/02/2024] [Revised: 02/29/2024] [Accepted: 04/01/2024] [Indexed: 04/08/2024]
Abstract
Nitrogen (N) concentrations in many lakes have decreased substantially in recent years due to external load reduction to mitigate harmful algal blooms. However, little attention has been paid to the linkage between the lakes' nitrogen removal efficiency and improved water quality in lakes, especially the variation of denitrification rate (DNR) under decreasing N concentrations. To understand the efficiency of N removal under improving water quality and its influence on the N control targets in Lake Taihu, a denitrification model based on in situ experimental results was developed and long-term (from 2007 to 2022) water quality and meteorological observations were used to estimate DNR and relate it to the amount of N removal (ANR) from the lake. The concentration of total nitrogen (TN) in Lake Taihu decreased from 3.28 mg L-1 to 1.41 mg L-1 from 2007 to 2022 but the reduction showed spatial heterogeneity. The annual mean DNR decreased from 45.6 μmol m-2 h-1 to 4.2 μmol m-2 h-1, and ANR decreased from 11.85×103 t yr-1 to 1.17×103 t yr-1 during the study years. N budget analysis suggested that the amount of N removed by denitrification accounted for 23.3 % of the external load in 2007, but decreased to only 4.0 % in 2022. Thus, the contribution of N removal by internal N cycling decreased significantly as water quality improved. Notably, the proportion of ANR in winter to total ANR increased from 14 % in 2007 to 23 % in 2022 due to warming. This could potentially lead to N deficiencies in spring and summer, thus limiting the availability of N to phytoplankton. A TN concentration of less than 1.0 mg L-1 in the lake and 1.5 mg L-1 in the inflowing lake zones in spring contribute to local N-limitation in Lake Taihu for cyanobacteria control. Our study revealed a general pattern that N removal efficiency decreases with improved water quality, which is instructive for eutrophic lakes in nitrogen management.
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Affiliation(s)
- Lijuan Kang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Mengyuan Zhu
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China
| | - Guangwei Zhu
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
| | - Hai Xu
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China
| | - Wei Zou
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China
| | - Man Xiao
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China
| | - Chaoxuan Guo
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China
| | - Yunlin Zhang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China
| | - Boqiang Qin
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China
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Peng J, Chen J, Liu S, Liu T, Cao M, Nanding N, Zhuang L, Bao A, De Maeyer P. Dynamics of algal blooms in typical low-latitude plateau lakes: Spatiotemporal patterns and driving factors. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 345:123453. [PMID: 38286264 DOI: 10.1016/j.envpol.2024.123453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 12/19/2023] [Accepted: 01/24/2024] [Indexed: 01/31/2024]
Abstract
The alpine lakes distributed on the plateau are crucial for the hydrological, and biogeochemical cycle, and also serve as a guarantee for regional economic development and human survival. However, under the influence of human interference and climate fluctuations, lakes are facing problems of eutrophication and subsequent algal blooms (ABs) with acceleration, and the development and driving factors of this phenomenon need to be considered as a whole. In this study, ten lakes located on the Yunnan-Guizhou Plateau were selected as the study area to analyze the spatiotemporal distribution of ABs and possible controlling forces. The FAI (Floating Algae Index) derived from multiple MODIS products and water quality data under high-frequency monitoring were selected as the data sources for characterizing ABs. Three nutrient parameters and five meteorological variables were used to explore the driving factors affecting ABs. Various methods of trend detection and correlation analysis have been applied. The main results are as follows: (1) Dianchi Lake (in lake area) and Xingyun Lake (in area proportion) are the two lakes with the most serious ABs in the historical period; (2) ABs are mainly distributed on the shoreline and northern edge of lakes, and tend to stay away from the lake center during high-temperature periods of the day; (3) Six lakes show a decreasing trend in ABs, especially after 2018, while other lakes (including Fuxian, Chenghai, Yangzong, and Erhai) are increasing, not only in peak value but also in duration; (4) Lakes with severe ABs are all P-restricted lakes, the minimum temperature is the most sensitive meteorological factor, while the impact of precipitation against ABs has a time lag; (5) Establishing a warning system of temperature and nutrient concentration is critical in ABs adaptive strategy. This study is expected to provide scientific references for regional water management and the restoration of the eutrophic aquatic ecosystem.
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Affiliation(s)
- Jiabin Peng
- School of Earth Sciences, Yunnan University, Kunming, 650500, China
| | - Junxu Chen
- School of Earth Sciences, Yunnan University, Kunming, 650500, China; International Joint Research Center for Karstology, Yunnan University, Kunming, 650091, China.
| | - Shiyin Liu
- Institute of International Rivers and Eco-security, Yunnan University, Kunming, 650500, China
| | - Tie Liu
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, China
| | - Min Cao
- School of Earth Sciences, Yunnan University, Kunming, 650500, China; International Joint Research Center for Karstology, Yunnan University, Kunming, 650091, China
| | - Nergui Nanding
- School of Earth Sciences, Yunnan University, Kunming, 650500, China
| | - Liangyu Zhuang
- Institute of International Rivers and Eco-security, Yunnan University, Kunming, 650500, China
| | - Anming Bao
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, China
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Wei J, Li Q, Liu W, Zhang S, Xu H, Pei H. Changes of phytoplankton and water environment in a highly urbanized subtropical lake during the past ten years. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 879:162985. [PMID: 36958549 DOI: 10.1016/j.scitotenv.2023.162985] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 03/15/2023] [Accepted: 03/17/2023] [Indexed: 05/17/2023]
Abstract
Phytoplankton and water quality changes in highly urbanized lakes affect the surrounding water safety. However, due to the complexity and variability of natural changes and human disturbances, it is difficult for multi-year research with yearly sampling frequency to cover accurate changes of phytoplankton and water environment or provide constructive suggestions for managers. Based on monthly monitoring data spanning 2011-2020 in a highly urbanized subtropical lake (Hongze Lake, China), Mann-Kendall test, ANOVA analysis and variation partitioning analysis were used to assess the changes of phytoplankton and water environment, and detect dynamic responses of phytoplankton to environmental changes. Rising water temperature during winter and spring, the decrease in nitrate, and the increase in water flow and turbidity were the main environmental characteristics from 2011 to 2020. The average and maximum abundance of Chlorophyta, Bacillariophyta, and Cryptophyta significantly declined, while changes in Cyanobacteria were characterized by an increase of N2-fixing filamentous cyanobacteria and a decrease of non-filamentous cyanobacteria. The rising water temperature during spring may promote the early growth of N2-fixing filamentous cyanobacteria. The decrease in nitrate mainly resulted in the decrease of Chlorophyta and non-filamentous cyanobacteria, and the increase of N2-fixing filamentous cyanobacteria during summer and autumn. The increase of turbidity and water flow inhibited the growth of Chlorophyta, Bacillariophyta, Cryptophyta, and non-filamentous cyanobacteria, but created favourable conditions for the growth of N2-fixing filamentous cyanobacteria. In summer and autumn, managers should focus on the proliferation of N2-fixing filamentous cyanobacteria when precipitation increase, nitrogen nutrients decrease, and non-filamentous cyanobacteria risk under opposite conditions. These findings greatly improved our understanding of the dynamic response of phytoplankton communities to natural changes and anthropogenic disturbances in the urbanized subtropical lakes, and can be used to develop lake management strategies.
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Affiliation(s)
- Jielin Wei
- School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Qian Li
- Xuzhou Department of Hydrology and Water Resources Survey Office in Jiangsu Province, Xuzhou 221000, China
| | - Wei Liu
- Huai'an Department of Hydrology and Water Resources Survey Office in Jiangsu Province, Huai'an 223005, China
| | - Shasha Zhang
- School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Hangzhou Xu
- School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China; Shandong Provincial Engineering Center on Environmental Science and Technology, Jinan 250061, China
| | - Haiyan Pei
- School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China; Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; Shandong Provincial Engineering Center on Environmental Science and Technology, Jinan 250061, China.
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Yi X, Zou R, Liao X, Guo H, Liu Y. Too ill to cure? - An uncertainty-based probabilistic model assessment on one of China's most eutrophic lakes. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 328:116916. [PMID: 36470004 DOI: 10.1016/j.jenvman.2022.116916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 11/21/2022] [Accepted: 11/26/2022] [Indexed: 06/17/2023]
Abstract
Eutrophication is a global challenge, which is exemplified by the tremendous efforts but little results in restoring the sixth largest and also one of the most eutrophic freshwater lakes in China, Lake Dianchi. Considering large parametric uncertainties in water quality modeling, the traditionally used deterministic water quality model is expanded to a probabilistic model to explore the Lake Dianchi's potential responses to different levels of pollutant load reductions. The results show that, given the long pollution history and severe pollution state in Lake Dianchi, a minimum pollution load reduction by half (base year 2003) is required to maintain the water quality state as it is now in 40 years. At least a 60% nutrient load reduction is required to generate any likelihood of water quality improvement, however, the system stabilizes quickly after about 10 years, which may explain why tremendous investments have generated little results. 80% of nutrient load reduction for 40 years has 95% probability of meeting the TN target but only a below 50% (45%) probability in meeting the TP target, and even less to meet water quality target for Chla. The feasibility of ever reaching the Chinese drinking water standards for total phosphorous and total nitrogen is questionable.
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Affiliation(s)
- Xuan Yi
- China South-to-North Water Diversion Corporation Limited, Beijing, 100036, China; College of Environmental Science and Engineering, The Key Laboratory of Water and Sediment Sciences Ministry of Education, Peking University, Beijing, 100871, China
| | - Rui Zou
- Rays Computational Intelligence Lab, Beijing Inteliway Environmental Ltd, Beijing, 100871, China; Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Kunming, 650034, China
| | - Xiawei Liao
- Bay Area International Business School, Beijing Normal University, Zhuhai, 519087, Guangdong Province, China.
| | - Huaicheng Guo
- College of Environmental Science and Engineering, The Key Laboratory of Water and Sediment Sciences Ministry of Education, Peking University, Beijing, 100871, China
| | - Yong Liu
- College of Environmental Science and Engineering, The Key Laboratory of Water and Sediment Sciences Ministry of Education, Peking University, Beijing, 100871, China
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Zhang J, Song Z, Li Z, Yang J, Xie Z. Life history and population ecology of Radix swinhoei (Lymnaeidae) in nearshore regions of a hypereutrophic plateau lake. Ecol Evol 2022; 12:e9631. [PMID: 36532136 PMCID: PMC9750820 DOI: 10.1002/ece3.9631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 10/03/2022] [Accepted: 11/27/2022] [Indexed: 12/23/2022] Open
Abstract
Accurate assessment of life history and population ecology of widespread species in ultra-eutrophic freshwater lakes is a prerequisite for understanding the mechanisms by which widespread species respond to eutrophication. Freshwater pulmonate (Radix swinhoei) is widespread and abundant in many eutrophic water bodies in Asia. Despite its key roles in eutrophic lake systems, the information on life history and population ecology of R. swinhoei is lacking, especially in ultra-eutrophic freshwater plateau lakes. Here, we conducted a 1-year survey of R. swinhoei with monthly collections to measure the life history traits (life span and growth), annual secondary production, and population size structure of R. swinhoei in nearshore regions with a high seasonally variation of nutrients in Lake Dianchi, a typic hypereutrophic plateau lake in Southwest China. Our results showed that R. swinhoei had the highest biomass in autumn and had the lowest in winter. Its maximum potential life span was 2.5 years, with three recruitment periods (November, March, and July) within a year. Its annual secondary production and P/B ratio were 137.19 g WW/m2 and 16.05, respectively. Redundancy analysis showed that eutrophication-related environmental factors had weak correlations with population size structure of R. swinhoei. Our results suggested that R. swinhoei is a typical r-strategist with high secondary production and thrive in eutrophic environment. Our study can help better understand the mechanisms for widespread species to survive eutrophication and could also be relevant for biodiversity conservation and management of eutrophic ecosystems.
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Affiliation(s)
- Junqian Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of HydrobiologyChinese Academy of SciencesWuhanChina
| | - Zhuoyan Song
- Great Lakes Institute for Environmental ResearchUniversity of WindsorWindsorOntarioCanada
| | - Zhengfei Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of HydrobiologyChinese Academy of SciencesWuhanChina
| | - Jiali Yang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of HydrobiologyChinese Academy of SciencesWuhanChina,University of Chinese Academy of SciencesBeijingChina
| | - Zhicai Xie
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of HydrobiologyChinese Academy of SciencesWuhanChina
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Tong Y, Huang Z, Janssen ABG, Wishart M, He W, Wang X, Zhao Y. Influence of social and environmental drivers on nutrient concentrations and ratios in lakes: A comparison between China and Europe. WATER RESEARCH 2022; 227:119347. [PMID: 36399843 DOI: 10.1016/j.watres.2022.119347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 10/24/2022] [Accepted: 11/08/2022] [Indexed: 06/16/2023]
Abstract
Global anthropogenic flows of nitrogen (N) and phosphorus (P) have exceeded planetary boundaries with significant implications for pollution of the freshwater resources in the world. Understanding the global patterns and drivers of N and P concentrations and their ratios in the lakes could help design more effective management and remediation strategies to mitigate the impacts of eutrophication. While a suite of drivers are associated with the sources of nutrients, their transport and internal processes that control concentrations of N and P in the lakes, much less is known about the relative importance of different drivers in explaining spatial variations of lake nutrients and ratios. In this study, we compared N and P concentrations and their ratios in the lakes across China and Europe and examined the differences of dominant environmental and social drivers on lake nutrients. Our comparison showed that total nitrogen (TN) and total phosphorus (TP) concentrations were much higher in the lakes in China compared to those in Europe (i.e., TN: 1.13 mg/L in China vs. 0.64 mg/L in Europe; TP: 35.83 μg/L in China vs. 19.38 μg/L in Europe, the median value). However, lake N/P ratios for both regions were not statistically different. Concentrations of TN and TP showed decoupling in both regions, with the majority of lakes having high N/P mass ratios when evaluated by the commonly accepted threshold of 23 (i.e., 61% in China and 68% in Europe), indicating that phytoplankton are more P limited relative to N. Agricultural activity in the lake catchment is an important predictor for both nutrient concentrations and their ratio in Europe. This reflects successful investments in infrastructure and policy prescriptions in addressing point sources of pollution. In comparison, lake depth and water residence time are important in the decoupling of N and P concentrations in China. The regional difference between the dominant drivers can provide important insights into development of effective water pollution control measures. It is necessary for policy makers and water resource managers to be aware of large-scale imbalance of nutrients in lake due to the potential environmental consequences. A set of spatially flexible policies for water quality controls would be beneficial for sustaining the ecological integrity and future health of lakes.
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Affiliation(s)
- Yindong Tong
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; School of Science, Tibet University, Lhasa 850000, China.
| | - Zhao Huang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Annette B G Janssen
- Water Systems and Global Change Group, Wageningen University & Research, PO Box 47, 6700 AA Wageningen, the Netherlands
| | | | - Wei He
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, China
| | - Xuejun Wang
- College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Yingxin Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
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Xie H, Gao T, Wan N, Xiong Z, Dong J, Lin C, Lai X. Controls for multi-temporal patterns of riverine nitrogen and phosphorus export to lake: Implications for catchment management by high-frequency observations. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 320:115858. [PMID: 36056487 DOI: 10.1016/j.jenvman.2022.115858] [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: 05/10/2022] [Revised: 07/22/2022] [Accepted: 07/22/2022] [Indexed: 06/15/2023]
Abstract
Intensifying human activity coupled with climate change increase the transport of excess riverine nitrogen (N) and phosphorus (P) loading from catchment to lake, leading to eutrophication and harmful algal blooms worldwide. To improve understanding of multi-temporal patterns of riverine N and P export and their hydro-biogeochemical controls over both episodic events and long-term trend, we analyzed and interpreted high-frequency data of total nitrogen (TN), ammonia-nitrogen (NH4-N), and total phosphorus (TP) provided by an automatic water quality monitoring station in a typical agricultural catchment draining to Lake Chaohu, China. Mann-Kendall test revealed a significant decreasing trend of riverine N and P concentration most of the time during 2018-2020. At the sub-daily scale, intraday TN concentrations varied by more than 1 mg/L in 31.8% of the period. Monthly TN and TP concentrations were particularly high in December 2019, indicating combined effect of hydrologic (long dry antecedent period and subsequent intensive rainfall events) and anthropogenic controls (fertilization and agricultural drainage). Significantly higher TN concentrations in winter and TP concentrations in summer reflected coupled dominances of precipitation and temperature on hydrologic and biogeochemical processes. Rainfall events with very heavy intensity drove disproportionate N and P loads (more than 20% of the total export) in only 3.2% of the period. Moderate and very heavy events registered the highest TN and TP concentrations, respectively. Our results highlighted the importance of automatic water quality monitoring station to reveal dynamics of riverine N and P export, which may imply future nutrient loading abatement plans for lake-connected catchment.
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Affiliation(s)
- Hui Xie
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Tiantian Gao
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China; Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Nengsheng Wan
- Institute of Lake Ecology and Environment, Chaohu Lake Bureau of Anhui Province, Hefei, 238000, China
| | - Zhuyang Xiong
- Institute of Lake Ecology and Environment, Chaohu Lake Bureau of Anhui Province, Hefei, 238000, China
| | - Jianwei Dong
- School of Marine Science and Engineering, Nanjing Normal University, Nanjing, 210023, China
| | - Chen Lin
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Xijun Lai
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China.
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Ding S, Dan SF, Liu Y, He J, Zhu D, Jiao L. Importance of ammonia nitrogen potentially released from sediments to the development of eutrophication in a plateau lake. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 305:119275. [PMID: 35413405 DOI: 10.1016/j.envpol.2022.119275] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 04/01/2022] [Accepted: 04/04/2022] [Indexed: 06/14/2023]
Abstract
Sedimentary nitrogen (N) in lakes significantly influenced by eutrophication plays a detrimental role on the ecological sustainability of aquatic ecosystems. Here, we conducted a thorough analysis of the importance of N potentially released from sediments during the shift of "grass-algae" ecosystem in plateau lakes. From 1964 to 2013, the average total amount of sedimentary potential mineralizable organic nitrogen (PMON) and exchangeable N in whole Lake Dianchi were 5.50 × 103 t and 3.44 × 103 t, respectively. NH4+-N was the main product (>90%) of sedimentary PMON mineralization. The PMON in sediments had great release potential, which tended to regulate the distribution of aquatic plants and phytoplankton in Lake Dianchi and facilitated the replacement of dominant populations. Moreover, NH4+-N produced by sedimentary PMON mineralization and exchangeable NH4+-N have increased the difficulty and complexity of ecological restoration in Lake Dianchi to a certain extent. This study highlights the importance of sedimentary N in lake ecosystem degradation, showing the urgent need to reduce the continuous eutrophication of lakes and restore the water ecology.
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Affiliation(s)
- Shuai Ding
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; Environmental Standard Institute, Ministry of Ecology and Environment of the People's Republic of China, Beijing, 100012, China
| | - Solomon Felix Dan
- Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf, Beibu Gulf University, Qinzhou, 535011, China
| | - Yan Liu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; Environmental Standard Institute, Ministry of Ecology and Environment of the People's Republic of China, Beijing, 100012, China
| | - Jia He
- Kunming Institute of Eco-Environmental Sciences, Kunming, 650032, China
| | - Dongdong Zhu
- University of Brest, CNRS, IRD, Ifremer, Institut Universitaire Européen de la Mer, LEMAR, Rue Dumont d'Urville, 29280, Plouzané, France; Frontiers Science Center for Deep Ocean Multi-spheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China
| | - Lixin Jiao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; Institute of Water Environment Research, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
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