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Wang S, Ran F, Li Z, Yang C, Xiao T, Liu Y, Nie X. Coupled effects of human activities and river-Lake interactions evolution alter sources and fate of sedimentary organic carbon in a typical river-Lake system. Water Res 2024; 255:121509. [PMID: 38537491 DOI: 10.1016/j.watres.2024.121509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 02/28/2024] [Accepted: 03/23/2024] [Indexed: 04/24/2024]
Abstract
Interconnected river-lake systems record sedimentary organic carbon (OCsed) dynamics and watershed environmental changes, providing valuable information for global carbon budgets and watershed management. However, owing to the evolving river-lake interactions under global change, monitoring OCsed is difficult, thereby impeding the understanding of OCsed transport and fate. This study provided new insights into the dynamical mechanisms of OCsed in a typical river-lake system consisting of Dongting Lake and its seven inlet/outlet rivers (the three inlets of the Yangtze River and four tributaries) over the last century using stable isotope tracing and quantified the influences of climate change and human activities on OCsed. Results indicated that exogenous OC dominated the OCsed in the lake (58.2 %-89.0 %) and was lower in the west than in the east due to the differences in the material inputs and depositional conditions within the lake. Temporally, the distribution patterns of OCsed sources mainly responded to human activities in the basin rather than to climate change. Before 2005, the Yangtze River contributed the most OCsed (53.5 %-74.6 %), attributed to the high-intensity land use changes (path coefficient (r∂): 0.48, p-value < 0.01) and agriculture-industry activities (r∂: 0.44, p-value < 0.001) in the Yangtze River basin that increased soil erosion. After 2005, a large amount of Yangtze River OC was intercepted by the Three Gorges Dam, altering the OC exchange in the river-lake system and shifting OCsed dominance to the four tributaries (52.2 %-63.8 %). These findings highlight the active response of OCsed to the river-lake interaction evolution and anthropogenic control, providing critical information for regulating watershed management behavior under global change.
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Affiliation(s)
- Shilan Wang
- Hunan Provincial Key Laboratory for Eco-environmental Changes and Carbon Sequestration of the Dongting Lake Basin, School of Geographic Sciences, Hunan Normal University, Changsha, PR China; Institute of Interdisciplinary Studies, Hunan Normal University, Changsha 410081, PR China
| | - Fengwei Ran
- Hunan Provincial Key Laboratory for Eco-environmental Changes and Carbon Sequestration of the Dongting Lake Basin, School of Geographic Sciences, Hunan Normal University, Changsha, PR China; Institute of Interdisciplinary Studies, Hunan Normal University, Changsha 410081, PR China
| | - Zhongwu Li
- Hunan Provincial Key Laboratory for Eco-environmental Changes and Carbon Sequestration of the Dongting Lake Basin, School of Geographic Sciences, Hunan Normal University, Changsha, PR China; Institute of Interdisciplinary Studies, Hunan Normal University, Changsha 410081, PR China.
| | - Changrong Yang
- Hunan Provincial Key Laboratory for Eco-environmental Changes and Carbon Sequestration of the Dongting Lake Basin, School of Geographic Sciences, Hunan Normal University, Changsha, PR China; Institute of Interdisciplinary Studies, Hunan Normal University, Changsha 410081, PR China
| | - Tao Xiao
- Hunan Provincial Key Laboratory for Eco-environmental Changes and Carbon Sequestration of the Dongting Lake Basin, School of Geographic Sciences, Hunan Normal University, Changsha, PR China; Institute of Interdisciplinary Studies, Hunan Normal University, Changsha 410081, PR China
| | - Yaojun Liu
- Hunan Provincial Key Laboratory for Eco-environmental Changes and Carbon Sequestration of the Dongting Lake Basin, School of Geographic Sciences, Hunan Normal University, Changsha, PR China; Institute of Interdisciplinary Studies, Hunan Normal University, Changsha 410081, PR China
| | - Xiaodong Nie
- Hunan Provincial Key Laboratory for Eco-environmental Changes and Carbon Sequestration of the Dongting Lake Basin, School of Geographic Sciences, Hunan Normal University, Changsha, PR China; Institute of Interdisciplinary Studies, Hunan Normal University, Changsha 410081, PR China.
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Yang Y, Wang Y, Cong N, Wang N, Yao W. Impacts of the Three Gorges Dam on riparian vegetation in the Yangtze River Basin under climate change. Sci Total Environ 2024; 912:169415. [PMID: 38123078 DOI: 10.1016/j.scitotenv.2023.169415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 11/30/2023] [Accepted: 12/13/2023] [Indexed: 12/23/2023]
Abstract
As the largest hydroelectric project in the world, the Three Gorges Dam (TGD) is expected to have significant environmental and ecological impacts on riparian vegetation in the Yangtze River Basin (YRB). However, existing studies have mainly focused on small segments of the YRB. In addition, few studies have quantified the responses of riparian vegetation to both climatic factors and dam construction. In this study, we investigated riparian vegetation dynamics over the entire YRB before, during, and after the construction of TGD from 1982 to 2015 using the normalized difference vegetation index (NDVI). Furthermore, the effects of climatic factors and dam construction on riparian vegetation were quantitatively analyzed using path analysis. The results demonstrate that the YRB has experienced a generally greening trend after TGD construction. The impacts of climate change on riparian vegetation have exhibited notable spatial heterogeneity and temperature is the main climatic factor that affects riparian vegetation growth. Moreover, TGD becomes the major contributor to riparian vegetation dynamics in the YRB after TGD construction. TGD has not only directly enhanced riparian vegetation but also indirectly affected riparian vegetation by regulating the microclimate. This study highlights the significance of anthropogenic interference when evaluating the relationships between riparian vegetation and climatic factors, providing useful insights for the effective management and conservation of large-scale riparian ecosystems.
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Affiliation(s)
- Yang Yang
- State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China; Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
| | - Yihang Wang
- State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China
| | - Nan Cong
- Lhasa Plateau Ecosystem Research Station, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Nan Wang
- State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China
| | - Weiwei Yao
- State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China; College of Ecological Engineering, Guizhou University of Engineering Science, Bijie 551700, China.
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Liu Y, Song C, Yang X, Zhuo H, Zhou Z, Cao L, Cao X, Zhou Y, Xu J, Wan L. Hydrological regimes and water quality variations in the Yangtze River basin from 1998 to 2018. Water Res 2024; 249:120910. [PMID: 38016223 DOI: 10.1016/j.watres.2023.120910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 11/14/2023] [Accepted: 11/21/2023] [Indexed: 11/30/2023]
Abstract
Understanding the long-term variations in basins that undergo large-scale hydroelectric projects is crucial for effective dam operation and watershed management. In this study, comprehensive analyses were conducted on a dataset spanning over 20 years (1998-2018) of hydrological regime and physicochemical parameters from the Yangtze River basin to evaluate the potential impacts of the Three Gorges Dam. Water level significantly increased from 128.75±58.18 m in 2002 to 136.78±55.05 m in 2005, and the mean flow velocity significantly decreased from 2004 to 2010. However, no significant change in the flow was observed in the basin. Meanwhile, remarkable fluctuations in physicochemical parameters, including dissolved oxygen, chemical oxygen demand, conductivity, hardness, and alkalinity, were mainly observed during impoundment (2003-2009). After that, the above parameters tended to stabilize, and some even returned to their original levels. The dam's retention effect significantly reduced the suspended solids (SS) in both up- and downstream, to only one-third of the pre-operation level. And total phosphorus and chemical oxygen demand also significantly decreased with the decline of SS. Particularly, ammonium also showed a significant downward trend, with the up- and downstream of the dam falling by 36.8 % and 26.1 %, respectively. However, the increasing total nitrogen (7.5 % and 20.0 % up- and downstream of the dam, respectively) still threatened the water quality of the basin, especially in the estuaries. Additionally, the significant decline in dissolved oxygen downstream (from 8.53±1.08 mg/L to 8.11±1.36 mg/L) also exacerbated the hypoxia in the Yangtze River estuary. The results demonstrated the long-term impact of the construction of the Three Gorges Dam on the environmental elements of the Yangtze River basin, which provides reference data and guidance for the construction of big dams in major rivers in the future.
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Affiliation(s)
- Yunbing Liu
- Changjiang Basin Ecology and Environment Monitoring and Scientific Research Center, Changjiang Basin Ecology and Environment Administration, Ministry of Ecology and Environment, No. 13 Yongqing Road, Wuhan 430010, China
| | - Chunlei Song
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, 7# Donghu South Road, Wuhan 430072, China
| | - Xia Yang
- China Three Gorges Corporation Basin Hub Operation Management Center, Three Gorges Dam Area Environmental Protection Building, Yichang 443000, China
| | - Haihua Zhuo
- Changjiang Basin Ecology and Environment Monitoring and Scientific Research Center, Changjiang Basin Ecology and Environment Administration, Ministry of Ecology and Environment, No. 13 Yongqing Road, Wuhan 430010, China
| | - Zheng Zhou
- Changjiang Basin Ecology and Environment Monitoring and Scientific Research Center, Changjiang Basin Ecology and Environment Administration, Ministry of Ecology and Environment, No. 13 Yongqing Road, Wuhan 430010, China
| | - Lu Cao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, 7# Donghu South Road, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100039, China
| | - Xiuyun Cao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, 7# Donghu South Road, Wuhan 430072, China
| | - Yiyong Zhou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, 7# Donghu South Road, Wuhan 430072, China
| | - Jie Xu
- Changjiang Basin Ecology and Environment Monitoring and Scientific Research Center, Changjiang Basin Ecology and Environment Administration, Ministry of Ecology and Environment, No. 13 Yongqing Road, Wuhan 430010, China.
| | - Lingling Wan
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, 7# Donghu South Road, Wuhan 430072, China.
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Le H, Zhao C, Xiong G, Shen G, Xu W, Deng Y, Xie Z. Disentangling the role of environmental filtering and biotic resistance on alien invasions in a reservoir area. Ecol Appl 2024; 34:e2835. [PMID: 36890673 DOI: 10.1002/eap.2835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Revised: 01/17/2023] [Accepted: 01/24/2023] [Indexed: 06/18/2023]
Abstract
Large-scale water conservancy projects benefit human life but have modified the landscape and provided opportunities for alien plant invasions. Understanding the environmental (e.g., climate), human-related (e.g., population density, proximity to human activities), and biotic (e.g., native plant, community structure) factors driving invasions is essential in the management of alien plants and biodiversity conservation in areas with intense human pressure. To this end, we investigated the spatial patterns of alien plant species distribution in the Three Gorges Reservoir Area (TGRA) of China and distinguished the role of the external environment and community characteristics in determining the occurrence of alien plants with differing levels of known invasion impacts in China using random forest analyses and structural equation models. A total of 102 alien plant species belonging to 30 families and 67 genera were recorded, the majority being annual and biennial herbs (65.7%). The results showed a negative diversity-invasibility relationship and supported the biotic resistance hypothesis. Moreover, percentage coverage of native plants was found to interact with native species richness and had a predominant role in resisting alien plant species. We found alien dominance was mainly the result of disturbance (e.g., changes in hydrological regime), which drove native plant loss. Our results also demonstrated that disturbance and temperature were more important for the occurrence of malignant invaders than all alien plants. Overall, our study highlights the importance of restoring diverse and productive native communities in resistance to invasion.
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Affiliation(s)
- Haichuan Le
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, No.20 Nanxincun, Xiangshan, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Changming Zhao
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, No.20 Nanxincun, Xiangshan, Beijing, 100093, China
| | - Gaoming Xiong
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, No.20 Nanxincun, Xiangshan, Beijing, 100093, China
| | - Guozhen Shen
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, No.20 Nanxincun, Xiangshan, Beijing, 100093, China
| | - Wenting Xu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, No.20 Nanxincun, Xiangshan, Beijing, 100093, China
| | - Ying Deng
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, No.20 Nanxincun, Xiangshan, Beijing, 100093, China
| | - Zongqiang Xie
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, No.20 Nanxincun, Xiangshan, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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Fan J, Galoie M, Motamedi A. Quantitative assessment of the variations in monthly precipitation trends induced by the impact of three gorges dam. Environ Monit Assess 2023; 195:1477. [PMID: 37966619 DOI: 10.1007/s10661-023-12116-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 11/08/2023] [Indexed: 11/16/2023]
Abstract
There are many studies that have examined the impact of the Three Gorges Dam (TGD) on changes in meteorological data, and most of them concluded that the TGD significantly reduced precipitation without taking into account the negative trends that had already existed before the impoundment. In this study, the investigation focused on the monthly precipitation data, and the Mann-Kendall (MK) trend analysis was conducted to show that the TGD had little effect on the trends of the precipitation data. Monthly data (1980-2018) from 19 stations upstream and downstream of the TGD and 5 stations located far from the main river were extracted. The analysis and results showed that although the linear long-term (1980-2018) precipitation trend upstream of the TGD was downward, the MK trend analysis showed that the precipitation trends became upward after impoundment. This situation existed even for station data located outside the region. Also, the analysis of monthly trends in different seasons showed that in spring and winter, there was only a very weak downward trend in monthly precipitation, while in summer and autumn, the trends were upward with steeper slopes. Following the upward trends of the monthly precipitation, the TGD generally positively intensified the monthly precipitation trends upstream and downstream of the dam, with the exception of a few months when total precipitation amounts were consistently low. In contrast to the trend analysis, which showed small and insignificant variations in precipitation data, the 12-month SPEI analysis showed a significant deterioration (about 20%) in the wetness index after impoundment both upstream and downstream of the TGD, while this situation did not occur outside the region. Thus, the TGD has extended dry periods both upstream and downstream of the dam over the past two decades.
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Affiliation(s)
- Jihui Fan
- Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, Sichuan, 610299, China.
| | - Majid Galoie
- Civil Engineering Department, Imam Khomeini International University, Qazvin, 34148-96818, Iran
| | - Artemis Motamedi
- Civil Engineering Department, Buein Zahra Technical University, Imam Khomeini Blvd, Buein Zahra, Qazvin, 3451745346, Iran
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Gong Y, Tong Y, Jiang H, Xu N, Yin J, Wang J, Huang J, Chen Y, Jiang Q, Li S, Zhou Y. Three Gorges Dam: Potential differential drivers and trend in the spatio-temporal evolution of the change in snail density based on a Bayesian spatial-temporal model and 5-year longitudinal study. Parasit Vectors 2023; 16:232. [PMID: 37452398 PMCID: PMC10349508 DOI: 10.1186/s13071-023-05846-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 06/21/2023] [Indexed: 07/18/2023] Open
Abstract
BACKGROUND Snail abundance varies spatially and temporally. Few studies have elucidated the different effects of the determinants affecting snail density between upstream and downstream areas of the Three Gorges Dam (TGD). We therefore investigated the differential drivers of changes in snail density in these areas, as well as the spatial-temporal effects of these changes. METHODS A snail survey was conducted at 200 sites over a 5-year period to monitor dynamic changes in snail abundance within the Yangtze River basin. Data on corresponding variables that might affect snail abundance, such as meteorology, vegetation, terrain and economy, were collected from multiple data sources. A Bayesian spatial-temporal modeling framework was constructed to explore the differential determinants driving the change in snail density and the spatial-temporal effects of the change. RESULTS Volatility in snail density was unambiguously detected in the downstream area of the TGD, while a small increment in volatility was detected in the upstream area. Regarding the downstream area of the TGD, snail density was positively associated with the average minimum temperature in January of the same year, the annual Normalized Difference Vegetation Index (NDVI) of the previous year and the second, third and fourth quartile, respectively, of average annual relative humidity of the previous year. Snail density was negatively associated with the average maximum temperature in July of the previous year and annual nighttime light of the previous year. An approximately inverted "U" curve of relative risk was detected among sites with a greater average annual ground surface temperature in the previous year. Regarding the upstream area, snail density was positively associated with NDVI and with the second, third and fourth quartile, respectively, of total precipitation of the previous year. Snail density was negatively associated with slope. CONCLUSIONS This study demonstrated a rebound in snail density between 2015 and 2019. In particular, temperature, humidity, vegetation and human activity were the main drivers affecting snail abundance in the downstream area of the TGD, while precipitation, slope and vegetation were the main drivers affecting snail abundance in the upstream area. These findings can assist authorities to develop and perform more precise strategies for surveys and control of snail populations.
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Affiliation(s)
- Yanfeng Gong
- Fudan University School of Public Health, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
| | - Yixin Tong
- Fudan University School of Public Health, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
| | - Honglin Jiang
- Fudan University School of Public Health, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
| | - Ning Xu
- Fudan University School of Public Health, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
| | - Jiangfan Yin
- Fudan University School of Public Health, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
| | - Jiamin Wang
- Fudan University School of Public Health, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
| | - Junhui Huang
- Fudan University School of Public Health, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
| | - Yue Chen
- School of Epidemiology and Public Health, Faculty of Medicine, University of Ottawa, 600 Peter Morand Crescent, Ottawa, ON K1G 5Z3 Canada
| | - Qingwu Jiang
- Fudan University School of Public Health, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
| | - Shizhu Li
- Chinese Center for Disease Control and Prevention, NHC Key Laboratory of Parasite and Vector Biology, National Institute of Parasitic Diseases, Chinese Center for Tropical Diseases Research, Shanghai, 200025 China
| | - Yibiao Zhou
- Fudan University School of Public Health, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong’an Road, Xuhui District, Shanghai, 200032 China
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Gong Y, Tong Y, Jiang H, Xu N, Yin J, Wang J, Huang J, Chen Y, Jiang Q, Li S, Zhou Y. Three Gorges Dam: the changing trend of snail density in the Yangtze River basin between 1990 and 2019. Infect Dis Poverty 2023; 12:45. [PMID: 37118831 PMCID: PMC10142781 DOI: 10.1186/s40249-023-01095-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 04/19/2023] [Indexed: 04/30/2023] Open
Abstract
BACKGROUND The area of Oncomelania hupensis snail remains around 3.6 billion m2, with newly emerging and reemergent habitats continuing to appear in recent years. This study aimed to explore the long-term dynamics of snail density before and after the operation of Three Gorges Dam (TGD). METHODS Data of snail survey between 1990 and 2019 were collected from electronic databases and national schistosomiasis surveillance. Meta-analysis was conducted to estimate the snail density. Joinpoint model was used to identify the changing trend and inflection point. Inverse distance weighted interpolation (IDW) was used to determine the spatial distribution of recent snail density. RESULTS A total of 3777 snail survey sites with a precise location of village or beach were identified. For the downstream area, snail density peaked in 1998 (1.635/0.11 m2, 95% CI: 1.220, 2.189) and fluctuated at a relatively high level before 2003, then declined steadily from 2003 to 2012. Snail density maintained lower than 0.150/0.11 m2 between 2012 and 2019. Joinpoint model identified the inflection of 2003, and a significant decreasing trend from 2003 to 2012 with an annual percentage change (APC) being - 20.56% (95% CI: - 24.15, - 16.80). For the upstream area, snail density peaked in 2005 (0.760/0.11 m2, 95% CI: 0.479, 1.207) and was generally greater than 0.300/0.11 m2 before 2005. Snail density was generally lower than 0.150/0.11 m2 after 2011. Snail density showed a significant decreasing trend from 1990 to 2019 with an APC being - 6.05% (95% CI: - 7.97, - 7.09), and no inflection was identified. IDW showed the areas with a high snail density existed in Poyang Lake, Dongting Lake, Jianghan Plain, and the Anhui branch of the Yangtze River between 2015 and 2019. CONCLUSIONS Snail density exhibited a fluctuating downward trend in the Yangtze River basin. In the downstream area, the operation of TGD accelerated the decline of snail density during the first decade period, then snail density fluctuated at a relatively low level. There still exists local areas with a high snail density. Long-term control and monitoring of snails need to be insisted on and strengthened.
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Affiliation(s)
- Yanfeng Gong
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
| | - Yixin Tong
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
| | - Honglin Jiang
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
| | - Ning Xu
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
| | - Jiangfan Yin
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
| | - Jiamin Wang
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
| | - Junhui Huang
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
| | - Yue Chen
- School of Epidemiology and Public Health, University of Ottawa, 600 Peter Morand Crescent, Ottawa, ON, K1G 5Z3, Canada
| | - Qingwu Jiang
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China
| | - Shizhu Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, 200025, China.
- Chinese Center for Tropical Diseases Research, NHC Key Laboratory of Parasite and Vector Biology, Shanghai, 200025, China.
| | - Yibiao Zhou
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China.
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China.
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai, 200032, China.
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8
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Ma Y, Chai Y, Xu YJ, Li Z, Zheng S. Spatial and Temporal Changes of Sand Mining in the Yangtze River Basin since the Establishment of the Three Gorges Dam. Int J Environ Res Public Health 2022; 19:16712. [PMID: 36554593 PMCID: PMC9778690 DOI: 10.3390/ijerph192416712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/06/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
The global demand for sand and gravel is at 50 billion tons per year, far exceeding global resource capacities. It reached 7.6 billion tons in 2021 in the Yangtze River Basin (YRB), China. However, production is severely limited in the YRB. Therefore, the incongruity between the supply and demand of river sand is prominent. Wise management of decreasing sand resources in the YRB has become critical since the Three Gorges Dam became operational in 2003. This study synthesized spatial and temporal changes in sand mining activities and quantities along the Yangtze River and its major tributaries from 2004 to 2020. Results from the study show that the mining amount during the period reached 76.2 million tons annually. At the same time, riverine suspended sediment discharge (SSD) downstream of the Three Gorges Dam decreased largely. SSD reduction leads to riverbed erosion, further limiting the riverine sand and gravel sources for mining. Thus, alternative sand and gravel resources, as well as optimizing supply/demand balance, are necessary for sustainable development. There is an urgent need to assess the relationship between river sand resources and exploitation in the YRB for creating a sand and gravel data management system in order to cope with the increasing incongruity between their supply and demand.
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Affiliation(s)
- Yugai Ma
- Department of Resource and Environment, Shijiazhuang University, Shijiazhuang 050035, China
| | - Yingying Chai
- College of Geography and Environment, Shandong Normal University, Jinan 250358, China
| | - Y. Jun Xu
- Coastal Studies Inst, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Zijun Li
- College of Geography and Environment, Shandong Normal University, Jinan 250358, China
| | - Shuwei Zheng
- College of Geography and Environment, Shandong Normal University, Jinan 250358, China
- Dongying Institute, Shandong Normal University, Dongying 257092, China
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9
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Guo Y, Deng B. Seasonal variation of heavy metals in suspended sediments downstream the Three Gorges Dam in the Yangtze River. Environ Monit Assess 2022; 194:660. [PMID: 35945328 DOI: 10.1007/s10661-022-10337-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
High sediment flux in large rivers provide sufficient dilution to the heavy metals' concentration. However, sediment starvation caused by hydrological engineering in recent decades has been reported worldwide. Thus, a study is necessary on the influences of recent declining sediment flux on heavy metal pollution change in the suspended sediments. In this study, heavy metal concentrations and speciation (Cd, Pb, Zn, Cu, Co, Ni, and Cr) in suspended sediments were investigated downstream the Three Gorges Dam (TGD) during dry and flood seasons. Substantial changes of Pb, Zn, Cd, and Cu along the river channel were found which were constrained by the dilution efficiency of suspended sediment during the dry season. High proportion of labile fraction revealed anthropogenic sources of heavy metal. Moreover, the historical trend of metal content illustrated TGD construction together with anthropogenic influx both contribute to the increasing environmental risk in the Yangtze River basin.
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Affiliation(s)
- Yutong Guo
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200241, China
| | - Bing Deng
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200241, China.
- Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, 519080, China.
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10
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Xu X, Xu Y, Xu N, Pan B, Ni J. Pharmaceuticals and personal care products (PPCPs) in water, sediment and freshwater mollusks of the Dongting Lake downstream the Three Gorges Dam. Chemosphere 2022; 301:134721. [PMID: 35483658 DOI: 10.1016/j.chemosphere.2022.134721] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/15/2022] [Accepted: 04/21/2022] [Indexed: 06/14/2023]
Abstract
Pharmaceuticals and personal care products (PPCPs) are a group of emerging anthropogenic pollutants. Here we investigated the occurrence and concentrations of 35 typical PPCPs in water, sediment, and freshwater mollusks (Hyriopsis cumingii, Unio douglasiae, Sinanodonta woodiana, Lamprotula leai and Corbicula fluminea) of the Dongting Lake downstream of the Three Gorges Dam. As results, 33 PPCPs were detected in water and sediment of the lake. Ketoprofen (not detected (ND)-292.8 ng/L, mean 91.1 ng/L) and roxithromycin (13.7-141.9 ng/L, mean 30.4 ng/L) were the primary PPCPs measured in lake water, while ibuprofen (ND-105.0 ng/g, mean 30.0 ng/g) and ketoprofen (ND-142.9 ng/g, mean 27.6 ng/g) were dominant in the sediment. Distinct seasonal difference in PPCP compositions was observed in both water and sediment of the Dongting Lake, potentially associated with the water-level fluctuations driven by the Three Gorges Dam operations. Ketoprofen and ibuprofen were also frequently detected in the soft tissues of freshwater mollusks, with concentrations of 42.5-1206.6 and 44.9-992.7 ng/g, respectively. Significant species-specific accumulation characteristics of PPCPs in mollusks were observed, with the highest total contents being reported for Corbicula fluminea (3.18 ± 1.13 μg/g). Moreover, gonads of mollusks were identified as the target organ to accumulate these compounds. Correlation analysis further revealed the strong associations of PPCP concentrations in mollusks with those in water and sediment, suggesting the importance of controlling dissolved and sedimentary bioavailability of PPCPs for ecological risk management in this freshwater lake ecosystems.
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Affiliation(s)
- Xuming Xu
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China; State Environmental Protection Key Laboratory of All Materials Fluxes in River Ecosystems, Peking University, Beijing, 100871, China
| | - Yaru Xu
- The Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Nan Xu
- The Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, 518055, China.
| | - Baozhu Pan
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, 710048, China
| | - Jinren Ni
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China; State Environmental Protection Key Laboratory of All Materials Fluxes in River Ecosystems, Peking University, Beijing, 100871, China
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11
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Luo W, Shen F, He Q, Cao F, Zhao H, Li M. Changes in suspended sediments in the Yangtze River Estuary from 1984 to 2020: Responses to basin and estuarine engineering constructions. Sci Total Environ 2022; 805:150381. [PMID: 34818786 DOI: 10.1016/j.scitotenv.2021.150381] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 09/12/2021] [Accepted: 09/12/2021] [Indexed: 06/13/2023]
Abstract
Suspended sediments in the estuary play an important role in regulating the erosion-accretion and shaping the geomorphological patterns. Yet, it can be strongly impacted by the human activities. Constructions of basin and estuarine engineering in the Yangtze River Estuary (YRE), including constructions of Three Gorges Dam (TGD) further upstream of the Yangtze River and Deep Waterway Project (DWP) in the estuary, have greatly modified the distribution of estuarine suspended sediment concentration (SSC). In this study, we retrieved the surface water SSC in the YRE from a total of 149 Landsat-TM/ETM+/OLI images (from 1984 to 2020) and 515 GOCI images (from 2011 to 2020) to obtain its long-term dynamics. The results indicate that the SSC estimation model performed well with a mean absolute percentage error of 12.83% and a root mean square error of 0.027 g/L. The SSC in the YRE demonstrated an overall declining pattern over the past 37 years, particularly during the flood season, which was related to the decrease in the sediment discharge of Yangtze River. The SSC in different sub-regions across the entire YRE responded differently to the reduced sediment discharge caused by the impoundment of the TGD. The SSC in the inner estuary responded promptly with a 40.3% decline noted immediately after the impoundment of the TGD, whereas hysteresis of SSC changes was found in the estuarine turbidity maximum zone (TMZ) and have begun to decline by 20.0-30.0% in the recent 5 years. Constructions of local estuarine engineering, such as the DWP also exert important controls on the estuarine SSC dynamics by blocking the lateral transport of suspended sediments between the shoal and the river channel. Our results highlight the strong influence of engineering constructions on the SSC dynamics in the world large river-influenced estuaries.
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Affiliation(s)
- Wei Luo
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, China
| | - Fang Shen
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, China; Institute of Eco-Chongming (IEC), East China Normal University, Shanghai, China.
| | - Qing He
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, China
| | - Fang Cao
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, China
| | - Haiyang Zhao
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, China
| | - Mengyu Li
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, China
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12
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Ran Y, Liu Y, Wu S, Li W, Zhu K, Ji Y, Mir Y, Ma M, Huang P. A higher river sinuosity increased riparian soil structural stability on the downstream of a dammed river. Sci Total Environ 2022; 802:149886. [PMID: 34525683 DOI: 10.1016/j.scitotenv.2021.149886] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 08/20/2021] [Accepted: 08/20/2021] [Indexed: 06/13/2023]
Abstract
Hydropower dam constructions and operations have dramatically changed the original hydrological regime of natural rivers. Because of significantly slashed and suspended sediments blocked by damming, discharged "clear" water was found to play a strong undercutting effect on the riverbank and to exacerbate riparian soil erosion on the downstream near dams. Yet, it is still an unsettled issue whether the instability of riparian soil structure would be simply correlated negatively with the distance to a dam. In this study, soils along the downstream riparian zone of a huge dam on the River Yangtze, China, were sampled to examine the distance effect on the riparian soil structural stability. Water-stable aggregates were fractionated by the wet-sieving method. Mean weight diameter (MWD) and geometric mean diameter (GMD) were used to indicate riparian soil stability. Further, the fractal dimension (D) and soil erodibility parameter (K) were used to represent the likelihood of riparian erosion. Our results revealed that riparian soil structural stability demonstrated a high spatial heterogeneity along the River Yangtze, and was less affected by the spatial distance to the dam. Rather, the soil stability was primarily influenced by a river shape index (sinuosity) and local edaphic properties. The river sinuosity index demonstrated a positive relationship with soil structural stability. Additionally, soil organic matter was found as a major edaphic factor in stabilizing soil structure. The results indicated that river sinuosity plays a crucial role in stabilizing soil by accumulating soil organic matters. Our findings implied that the potential negative impact of damming effect on soil stability may be attenuated by maintaining a higher sinuosity of the river. Against the risk of riparian soil erosion along the dammed river, the configuration of river morphology shall be considered as one of the potential managements in offsetting the negative impacts of damming.
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Affiliation(s)
- Yiguo Ran
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Yan Liu
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Shengjun Wu
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China.
| | - Wenjuan Li
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Kai Zhu
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China.
| | - Yongyue Ji
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yaseen Mir
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Maohua Ma
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China.
| | - Ping Huang
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China.
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13
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Wang H, Yuan W, Zeng Y, Liang D, Deng Y, Zhang X, Li Y. How does Three Gorges Dam regulate heavy metal footprints in the largest freshwater lake of China. Environ Pollut 2022; 292:118313. [PMID: 34634400 DOI: 10.1016/j.envpol.2021.118313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 09/12/2021] [Accepted: 10/06/2021] [Indexed: 06/13/2023]
Abstract
Herein, a two-dimensional (2-D) vertically-averaged hydrodynamic model was applied to study the heavy metal particle footprints pre- and post-Three Gorges Dam (TGD) in Poyang Lake. Two defined indexes-Reserve Impact Index (σRII) and Species Impact Index (ηSII) were applied to assess the potential impact of the copper footprint on nature reserves and sensitive species quantitatively. The results demonstrated that the movement speed, distribution, and trajectory of copper particle footprints differed enormously pre- and post-TGD. By contrast, the post-TGD footprints were more complex because of the dam-induced variations in hydrology and meteorology. TGD had both pros and cons for the copper footprint on the reserves based on the results of σRII. It had changed the way for the transport of heavy metals and altered the patterns of exposure risk in the reserves. Sustainable management of Poyang Lake could be achieved by optimizing daily monitoring works. The ηSII for Finless Porpoises do not differ significantly between scenarios, but the ηSII for Siberian White Cranes increased by 0.92 and 0.83 for the two periods pre- and post-TGD, respectively. Heavy metals in food sources and the excreta of Siberian White Cranes could be of great concern in future studies. This study provides a theoretical basis for the in-depth study of the TGD-induced impact on Poyang Lake and provides a reference for the long-term treatment of Poyang Lake and the protection of key species.
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Affiliation(s)
- Hua Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China.
| | - Weihao Yuan
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China
| | - Yichuan Zeng
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China
| | - Dongfang Liang
- Department of Engineering, University of Cambridge, Cambridge, CB2 1PZ, UK
| | - Yanqing Deng
- Water Quality Department, Jiangxi Hydrological Bureau, Nanchang, 330000, China
| | - Xinyue Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China
| | - Yuanyuan Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China
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14
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Zhao B, Yao P, Li D, Yu Z. Effects of river damming and delta erosion on organic carbon burial in the Changjiang Estuary and adjacent East China Sea inner shelf. Sci Total Environ 2021; 793:148610. [PMID: 34328970 DOI: 10.1016/j.scitotenv.2021.148610] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 06/17/2021] [Accepted: 06/18/2021] [Indexed: 06/13/2023]
Abstract
River damming reduces sediment load in rivers, leading to instability and erosion of coastal deltas; this is a global issue in many large-river delta-front estuaries (LDEs). The total organic carbon, stable carbon isotope, total nitrogen, lignin phenols in suspended particulate matter, and three sediment cores collected from the Changjiang LDE were analyzed to study the effects of river damming and delta erosion on the redistribution and burial of organic carbon (OC) in the coastal margin. The OC budgets that include the delta erosion process were established to better constrain the burial fluxes of OC in the Changjiang River system before and after river damming. We used a three-end-member mixing model with Monte Carlo simulation and found that the ratio of deltaic OC to riverine OC significantly increased in estuarine SPM and sediment cores in the Changjiang LDE after the operation of the Three Gorges Dam (TGD), reflective of reduced sediment load and enhanced delta erosion. Our budget showed that, compared with the pre-dam period (1953-1985), the burial of terrestrial OC in the Changjiang LDE sediments had been reduced by ~97.3%, on the basis of 72.7% and 82.7% reductions in sediment load and particulate OC flux, respectively. Although trapping of terrestrial OC in reservoirs is the key driver in these reductions, re-exposure and decomposition of OC from eroding delta sediments also contribute significantly to OC losses in coastal sediments. On the contrary, the ratio of marine OC to riverine OC increased in sediment cores after TGD building, due in part to more inputs of marine OC because of serious eutrophication in recent decades. As continued dam construction and sea-level rise change the spatial and temporal dynamics of carbon sequestration in the coastal zones of LDEs, further consideration of alterations in these carbon burial "hotspots" is needed in global carbon models.
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Affiliation(s)
- Bin Zhao
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, and Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Peng Yao
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, and Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China.
| | - Dong Li
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China
| | - Zhigang Yu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, and Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
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15
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Gao Y, Chen L, Zhang W, Li X, Xu Q. Spatiotemporal variations in characteristic discharge in the Yangtze River downstream of the Three Gorges Dam. Sci Total Environ 2021; 785:147343. [PMID: 33932668 DOI: 10.1016/j.scitotenv.2021.147343] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 03/29/2021] [Accepted: 04/20/2021] [Indexed: 06/12/2023]
Abstract
Large dams on rivers have substantial impacts on the flow process, sediment transport, and river morphology. The flow-sediment regimes and river morphology in the Yangtze River downstream of the Three Gorges Dam (TGD) have undergone significant adjustments owing to the impoundment of the TGD. Different methods have been adopted to assess the spatiotemporal variations in characteristic discharge in the reaches downstream of the TGD, which can quantitatively assess the channel-forming capacity of flow-sediment regimes. However, agreement on the spatiotemporal variations in characteristic discharge in a long-distance reach downstream of the TGD does not exist thus far. Therefore, in this study, the effective discharge, dominant discharge, and bankfull discharge were calculated to assess the spatiotemporal variations in the characteristic discharge from Yichang to Datong. It was found that, after the impoundment of the TGD, the attenuation of the flow process, bedload coarsening, and changes in the water surface slope together led to a decrease in dominant discharge, which was consistent with the adjustment of the main deformation area from the bankfull channel to the medium-flow channel. This indicates that the dominant discharge is most representative of the characteristic discharges in the reaches downstream of the TGD. Results show that the post-dam characteristic discharge at each station from Yichang to Datong was reduced by 700-5700 m3/s. Spatially, owing to the tributaries along the main stem, the characteristic discharge decreased from Yichang to Jianli and then increased from Jianli to Datong in the pre- and post-dam periods. This study serves as a valuable reference for quantitatively assessing the channel-forming capacity of flow-sediment regimes for other rivers worldwide. Moreover, it facilitates the prediction of the evolution of river morphology.
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Affiliation(s)
- Yu Gao
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China
| | - Li Chen
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China.
| | - Wei Zhang
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China.
| | - Xin Li
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China
| | - Quanxi Xu
- Bureau of Hydrology, Changjiang Water Resources Commission, Wuhan 430010, China
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16
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Zheng J, Arif M, Zhang S, Yuan Z, Zhang L, Dong Z, Tan X, Charles W, Li C. The convergence of species composition along the drawdown zone of the Three Gorges Dam Reservoir, China: implications for restoration. Environ Sci Pollut Res Int 2021; 28:42609-42621. [PMID: 33818726 DOI: 10.1007/s11356-021-13774-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 03/29/2021] [Indexed: 05/20/2023]
Abstract
Many rivers across the globe are regulated by dams, resulting in a strong alteration of the plant community composition of the drawdown zone. But, how these changes happen along the drawdown zone is less understood. In this study, a multivariate analysis was used to explore plant composition and similarity along the drawdown zone of the Three Gorges Dam Reservoir (TGDR), China. The dominant plant species, species richness, indicator species, and growth form were compared among the upstream, midstream, and downstream of the TGDR. Moreover, variation partitioning was used to determine the relative importance of environmental factors and spatial factors. Results showed that only a few species contributed the most to the community composition of the study area, and there was an extreme similarity in the plant community composition across the three different river segments. Furthermore, the results of the linear regression model demonstrated a steady declining trend in species richness along the drawdown zone, with the lowest species richness in the downstream segment. In addition, variation partitioning revealed 11% and 8% of the species composition change under environmental and spatial factors, respectively. Our results suggested that the dam impoundment led to the convergence of species composition along the drawdown zone of the TGDR, and environmental filtering and dispersal limitation played an imperative role in shaping species composition. The study highlighted the importance of restoration activities in overcoming the barriers of seed dispersal and seedling establishment in the degraded drawdown zone ecosystem of the TGDR.
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Affiliation(s)
- Jie Zheng
- Key Laboratory of Eco-environments in the Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources Research in the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Muhammad Arif
- Key Laboratory of Eco-environments in the Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources Research in the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Songlin Zhang
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China
| | - Zhongxun Yuan
- Key Laboratory of Eco-environments in the Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources Research in the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Limiao Zhang
- Key Laboratory of Eco-environments in the Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources Research in the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Zhi Dong
- Key Laboratory of Eco-environments in the Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources Research in the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Xue Tan
- Key Laboratory of Eco-environments in the Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources Research in the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Wokadala Charles
- Key Laboratory of Eco-environments in the Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources Research in the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Changxiao Li
- Key Laboratory of Eco-environments in the Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources Research in the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, 400715, China.
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Grabb KC, Ding S, Ning X, Liu SM, Qian B. Characterizing the impact of Three Gorges Dam on the Changjiang (Yangtze River): A story of nitrogen biogeochemical cycling through the lens of nitrogen stable isotopes. Environ Res 2021; 195:110759. [PMID: 33497682 DOI: 10.1016/j.envres.2021.110759] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 01/12/2021] [Accepted: 01/15/2021] [Indexed: 06/12/2023]
Abstract
The alterations of nitrogen sources and cycling within the Three Gorges Reservoir (TGR) and downstream the Changjiang were investigated to understand the impacts of the construction of the Three Gorges Dam (TGD) and anthropogenic inputs from the associated watershed. Water samples collected in October 2016 were analyzed for hydrologic parameters, nutrient concentrations, and stable isotopes of nitrate (NO3-), ammonium (NH4+) and particulate matter. Nitrate dual stable isotope values ranged from +5.8‰ to +7.1‰ and -1.9‰ to +0.4‰ for δ15N and δ18O, respectively. δ15N values in particulate nitrogen (PN) ranged from +0.5‰ to +8.5‰, with slightly lower values before the dam. δ15N-NH4+ values ranged between +10.5‰ and +19.4‰, likely reflecting the presence of ammonium assimilation throughout the TGR. The contribution of different nitrogen sources was calculated using a Bayesian mixing model. These sources, including soil organic nitrogen, ammonium fertilizer, and sewage effluent, contributed to elevated DIN concentrations within the TGR (83.2 μM-178.5 μM). The construction of the dam has also likely induced changes in the river environment such as ammonium assimilation in the surface waters and nitrification and/or remineralization within the deep waters of the TGR. Overall, during this investigation period, the TGR acted as a sink of PN (retaining 29%), yet negligibly influenced levels of TDN with ~96.5% of TDN exported to the downstream Changjiang and estuary. It is important to understand the long-term impacts of the TGD on the ecological environment of the Changjiang. This study highlights the influence that anthropogenic nitrogen sources have on the natural biogeochemical cycling within the TGR, showing the urgent need to reduce anthropogenic nitrogen pollution.
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Affiliation(s)
- Kalina C Grabb
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; MIT-WHOI Joint Program in Oceanography/Applied Ocean Science & Engineering, Cambridge and Woods Hole, MA, USA
| | - Shuai Ding
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
| | - Xiaoyan Ning
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
| | - Su Mei Liu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China.
| | - Bao Qian
- Bureau of Hydrology, Changjiang Water Resources Commission, Wuhan, 430010, China
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Wang S, Hou W, Jiang H, Huang L, Dong H, Chen S, Wang B, Chen Y, Lin B, Deng Y. Microbial diversity accumulates in a downstream direction in the Three Gorges Reservoir. J Environ Sci (China) 2021; 101:156-167. [PMID: 33334511 DOI: 10.1016/j.jes.2020.08.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 08/04/2020] [Accepted: 08/07/2020] [Indexed: 06/12/2023]
Abstract
Organic and inorganic materials migrate downstream and have important roles in regulating environmental health in the river networks. However, it remains unclear whether and how a mixture of materials (i.e., microbial species) from various upstream habitats contribute to microbial community coalescence upstream of a dam. Here we track the spatial variation in microbial abundance and diversity in the Three Gorges Reservoir based on quantitative PCR and 16S rRNA gene high-throughput sequencing data. We further quantitatively assess the relative contributions of microbial species from mainstem, its tributaries, and the surrounding riverbank soils to the area immediately upstream of the Three Gorges Dam (TGD). We found an increase of microbial diversity and the convergent microbial distribution pattern in areas immediately upstream of TGD, suggesting this area become a new confluence for microbial diversity immigrating from upstream. Indeed, the number of shared species increased from upstream to TGD but unique species decreased, indicating immigration of various sources of microbial species overwhelms local environmental conditions in structuring microbial community close to TGD. By quantifying the sources of microbial species close to TGD, we found little contribution from soils as compared to tributaries, especially for sites closer to TGD, suggesting tributary microbes have greater influence on microbial diversity and environmental health in the Three Gorges Reservoir. Collectively, our results suggest that tracking microbial geographic origin and evaluating accumulating effects of microbial diversity shed light on the ecological processes in microbial communities and provide information for regulating aquatic ecological health.
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Affiliation(s)
- Shang Wang
- CAS Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Weiguo Hou
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing 100083, China
| | - Hongchen Jiang
- School of Ocean Sciences, China University of Geosciences, Beijing 100083, China
| | - Liuqin Huang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China
| | - Hailiang Dong
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing 100083, China; Department of Geology and Environmental Earth Science, Miami University, Oxford, OH 45056, USA
| | - Shu Chen
- School of Environment and Resource, Southwest University of Science and Technology, Sichuan 621010, China.
| | - Bin Wang
- School of Environment and Resource, Southwest University of Science and Technology, Sichuan 621010, China
| | - Yongcan Chen
- School of Environment and Resource, Southwest University of Science and Technology, Sichuan 621010, China
| | - Binliang Lin
- Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China
| | - Ye Deng
- CAS Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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Geng M, Wang K, Yang N, Li F, Zou Y, Chen X, Deng Z, Xie Y. Evaluation and variation trends analysis of water quality in response to water regime changes in a typical river-connected lake (Dongting Lake), China. Environ Pollut 2021; 268:115761. [PMID: 33035913 DOI: 10.1016/j.envpol.2020.115761] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 09/26/2020] [Accepted: 09/28/2020] [Indexed: 06/11/2023]
Abstract
Lake water pollution has caused many serious ecological issues globally. An emerging public concern over water quality deterioration in lakes has heightened the need to evaluate the water quality of lakes at long-term scales, particularly for those with high hydrological alterations. This study combines the Mann-Kendall (M-K) test and self-organising map (SOM) to characterise and evaluate water quality trends in Dongting Lake, China, from 1991 to 2018, before and after the inauguration of the Three Gorges Dam (TGD). Herein, six water quality parameters were selected, namely pH, permanganate index (CODMn), ammonia nitrogen (NH3-N), total nitrogen (TN), total phosphorus (TP), and the five-day biochemical oxygen demand (BOD5). Our results show that the concentrations of TN and BOD5 increase significantly throughout the study period (|Z| ≥ 1.96). The number of abrupt change points for the six water quality parameters in the post-TGD period was greater than that in the pre-TGD period, which indicates an increased risk of water deterioration in the post-TGD period. The SOM results show that the pH values ranged from 7.64 to 7.85 among the four clusters; besides, the concentrations of the remaining water quality parameters from 1991 to 1997 and 2000 to 2003 were relatively lower, suggesting that the water quality in the pre-TGD period was better. The classification of TN and TP ranged from Level Ⅳ-Ⅴ among the clusters, which did not satisfy the level Ⅲ standard for potable water, thereby posing a higher ecological risk to the Dongting Lake. These results indicate the deterioration of the water quality in Dongting Lake during the post-TGD period under the influences of pollution load and hydrological regulation. Therefore, strict controls on the external nutrient loading and hydrological regulations should be considered for water quality management.
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Affiliation(s)
- Mingming Geng
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kelin Wang
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China
| | - Nan Yang
- College of Architecture and Urban Planning, Hunan City University, Yiyang, 413000, Hunan, China
| | - Feng Li
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China.
| | - Yeai Zou
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China
| | - Xinsheng Chen
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China
| | - Zhengmiao Deng
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China
| | - Yonghong Xie
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, 410125, Hunan, China
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Li J, Gao Y, Xu N, Li B, An R, Sun W, Borthwick AGL, Ni J. Perfluoroalkyl substances in the Yangtze River: Changing exposure and its implications after operation of the Three Gorges Dam. Water Res 2020; 182:115933. [PMID: 32650148 DOI: 10.1016/j.watres.2020.115933] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/30/2020] [Accepted: 05/11/2020] [Indexed: 06/11/2023]
Abstract
Potential ecological risk from perfluoroalkyl substances (PFASs) under changing exposure in large river systems has become a new challenge recently. Based on systematic monitoring of PFASs at 43 hydrologic stations along a 4300 km continuum of the Yangtze River, we investigated the ecological risk of PFASs under changing exposure resulting from operation of the Three Gorges Dam (TGD). Importantly, perfluorooctanoic acid (PFOA) was found extensively exposed in most mainstream water samples, accounting for about 90% of the total content of PFASs in both spring and autumn, while short-chain PFASs contributed more than PFOA in sediment. The significant inversion of long-chain PFASs occurrence from sediment to water reflected a profound change in exposure due to loss of finer sediments resulting from long-distance and long-term scour of the riverbed downstream of the TGD. The coarsening of bed materials would weaken sorption of long-chain PFASs in sediments and enhance their exposure in water, resulting in substantial increase of ecological risk to representative aquatic organisms. In the long term, particular attention should be paid to reduction of PFOA discharge to downstream of the TGD from typical industries. This also highlights the significance of huge dams to alternative exposures of persistent organic pollutants and the necessity of new strategy for ecological risk management of large river systems.
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Affiliation(s)
- Jie Li
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China
| | - Yue Gao
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Nan Xu
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
| | - Bin Li
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Rui An
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China
| | - Weiling Sun
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China
| | | | - Jinren Ni
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China; School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, China.
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21
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Wang Q, Zhou L, Little SH, Liu J, Feng L, Tong S. The geochemical behavior of Cu and its isotopes in the Yangtze River. Sci Total Environ 2020; 728:138428. [PMID: 32339845 DOI: 10.1016/j.scitotenv.2020.138428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 04/01/2020] [Accepted: 04/02/2020] [Indexed: 06/11/2023]
Abstract
Copper (Cu) isotopes can be a useful tool to constrain the interaction of water and the environment, but they have not been widely applied to riverine research in the preceding decades. Isotopically heavy Cu in rivers (global average: about +0.7‰) compared to rocks (at about 0‰) has been attributed to: a) the mobilization of heavy Cu during oxidative weathering, and b) partitioning between an isotopically heavy, organically complexed dissolved pool, and an isotopically light pool adsorbed to particulates. Here, we report Cu concentrations and isotope ratios of the main stream of the Yangtze River and its several tributaries. We find that the Yangtze River exhibits anomalously heavy Cu isotope compositions compared to other rivers: δ65CuNIST 976 of dissolved Cu for the main stream, from Chongqing to Nanjing, ranges from +0.59 to +1.65‰, while the tributaries vary from +0.48 to +1.20‰. A negative correlation is observed between Cu concentrations and Cu isotope compositions. We attribute the anomalous Cu isotope geochemistry of the Yangtze River to two key features of the basin: first, the influence of the Three Gorges Dam (TGD), and second, the presence of extensive Cu sulphide deposits close to the lower reaches of the river. In the upper reaches, downstream towards the TGD, δ65Cu values increase as Cu concentrations decrease, reflecting the preferential adsorption of light Cu by sedimenting particulate phases. δ65Cu values continue to increase to a maximum of +1.65‰ in the middle reaches, at Guangxingzhou. The lower reaches, from Jiujiang to Tongling, are characterized by less positive values of δ65Cu (at about +0.60‰), due to the oxidative weathering of Cu sulphide deposits. The overall Cu-δ65Cu trend in the river reflects mixing of these waters from the lower reaches, influenced by Cu sulphides, with waters from upstream, which have lower Cu concentrations and elevated δ65Cu values.
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Affiliation(s)
- Qian Wang
- State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 430074, China
| | - Lian Zhou
- State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 430074, China.
| | - Susan H Little
- Department of Earth Sciences, University College London, Gower Street, WC1E 6BT, London
| | - Jinhua Liu
- State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 430074, China
| | - Lanping Feng
- State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 430074, China
| | - Shuoyun Tong
- State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 430074, China
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Zhang C, Fujiwara M, Pawluk M, Liu H, Cao W, Gao X. Changes in taxonomic and functional diversity of fish communities after catastrophic habitat alteration caused by construction of Three Gorges Dam. Ecol Evol 2020; 10:5829-5839. [PMID: 32607193 PMCID: PMC7319164 DOI: 10.1002/ece3.6320] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 04/04/2020] [Accepted: 04/06/2020] [Indexed: 11/25/2022] Open
Abstract
Habitat alterations that result from anthropogenic disturbance impact both the abiotic and biotic conditions of ecosystems, causing changes in biodiversity in many parts of the world. Recently, the use of functional diversity has been suggested as an approach to better evaluate the effects of such disturbance on particular communities. Here, we investigated the temporal changes in species and functional diversities of fish communities in the downstream area of the Three Gorges Dam (TGD) before, during, and after impoundment. We found two regime shifts in the fish community in 2004 and 2013 following impoundment. Although taxonomic diversity declined sharply at the first regime shift, it increased at the second shift. On the other hand, functional diversity declined throughout the same period, indicating the loss of functional diversity despite increased species diversity. Our analysis also showed that the fish communities shifted from under-dispersion to over-dispersion due to both a decrease in the relative abundance of migratory fish and an increase in the number of fish adapted to the new hydrologic conditions. Our results indicated that the impacts of dams on downstream fish communities may change over time. Interactions between species may become more important when the environment is stable.
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Affiliation(s)
- Chen Zhang
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of HydrobiologyChinese Academy of SciencesWuhanChina
- University of Chinese Academy of SciencesBeijingChina
| | - Masami Fujiwara
- Department of Ecology and Conservation BiologyTexas A&M UniversityCollege StationTXUSA
| | - Michaela Pawluk
- Department of Wildlife and Fisheries SciencesTexas A&M UniversityCollege StationTXUSA
| | - Huanzhang Liu
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of HydrobiologyChinese Academy of SciencesWuhanChina
| | - Wenxuan Cao
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of HydrobiologyChinese Academy of SciencesWuhanChina
| | - Xin Gao
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of HydrobiologyChinese Academy of SciencesWuhanChina
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Dai X, Yu Z, Yang G, Wan R. Role of Flooding Patterns in the Biomass Production of Vegetation in a Typical Herbaceous Wetland, Poyang Lake Wetland, China. Front Plant Sci 2020; 11:521358. [PMID: 33178232 PMCID: PMC7596249 DOI: 10.3389/fpls.2020.521358] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 09/18/2020] [Indexed: 05/20/2023]
Abstract
Flooding is an important factor influencing the biomass production of vegetation in natural wetland ecosystems. However, how biomass production is linked to flooding patterns in wetland areas remains unclear. We utilized gauging station data, a digital elevation model, vegetation survey data, and a Landsat 8 image to study the effects of average inundation depth (AID) and inundation duration (IDU) of flooding on end-of-season biomass of vegetation in Poyang Lake wetland, in particular, after operation of Three Gorges Dam. The end-of-season biomass of wetland vegetation showed Gaussian distributions along both the AID and IDU gradients. The most favorable flooding conditions for biomass production of vegetation in the wetland had an AID ranging from 3.9 to 4.0 m and an IDU ranging from 39% to 41%. For sites with a lower AID (<3.9 m; IDU < 39%), the end-of-season biomass values were positively related, whereas for sites with a higher AID (4.0 m; IDU > 41%), the end-of-season biomass values were negatively related. After the operation of the Three Gorges Dam, flooding patterns characterized by AID and IDU of the Poyang Lake wetland were significantly alleviated, resulting in a mixed changing trend of vegetation biomass across the wetland. Compared with 1980-2002, the increase of end-of-season biomass in lower surfaces caused by the alleviated flooding pattern far exceeded the decrease of end-of-season biomass in higher surfaces, resulting in an end-of-season biomass increase of 1.0%-6.7% since 2003. These results improved our understanding of the production trends of vegetation in the wetland and provided additional scientific guidance for vegetation restoration and wetland management in similar wetlands.
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Affiliation(s)
- Xue Dai
- State Key Laboratory of Hydrology–Water Resources and Hydraulic Engineering, Hohai University, Nanjing, China
- College of Hydrology and Water Resources, Hohai University, Nanjing, China
- *Correspondence: Zhongbo Yu,
| | - Zhongbo Yu
- State Key Laboratory of Hydrology–Water Resources and Hydraulic Engineering, Hohai University, Nanjing, China
- College of Hydrology and Water Resources, Hohai University, Nanjing, China
- Rongrong Wan,
| | - Guishan Yang
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, CAS, Nanjing, China
- University of Chinese Academy of Sciences, Beijing, China
- Xue Dai,
| | - Rongrong Wan
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, CAS, Nanjing, China
- University of Chinese Academy of Sciences, Beijing, China
- Guishan Yang,
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Huang Y, Mi W, Hu Z, Bi Y. Effects of the Three Gorges Dam on spatiotemporal distribution of silicon in the tributary: evidence from the Xiangxi River. Environ Sci Pollut Res Int 2019; 26:4645-4653. [PMID: 30565109 DOI: 10.1007/s11356-018-3707-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 11/06/2018] [Indexed: 06/09/2023]
Abstract
In order to get insight into the impact of Three Gorges Dam construction on silicon distribution pattern due to the altered hydraulic and environmental conditions, the Xiangxi River was chosen as the delegate of the tributaries in the Three Gorges Reservoir; dissolved silica (DSi), biogenic silica (BSi), and lithogenic silica (LSi) were investigated monthly from November 2015 to October 2016 and the hydrodynamic conditions and environmental parameters were addressed synchronously. DSi, BSi, and LSi ranged from 56.07 to 106.07 μmol/L, 0 to 5.64 μmol/L, and 0.49 to 11.47 μmol/L, with the average concentration of 81.84 ± 14.65 μmol/L, 1.11 ± 0.69 μmol/L, and 2.68 ± 1.97 μmol/L, respectively. DSi was significantly lower in the wet season than the dry season (P < 0.05), but BSi and LSi showed a converse trend. DSi was the dominant component in the total silicon (> 90%) and it has a higher concentration in the midstream than other sites. While BSi and LSi exhibited a decrease trend from the upstream to the downstream. Statistical analysis showed that DSi and LSi was primarily controlled by discharge. BSi concentration was affected by algal growth since it was positively correlated with Chla. The backwater area retained 3.67% total silicon. It was concluded that the spatiotemporal heterogeneity of silicon distribution related to hydrodynamics was determined by the regulation of dam; permanent backwater area was the main deposition area for silicon.
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Affiliation(s)
- Yubo Huang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wujuan Mi
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Zhengyu Hu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Yonghong Bi
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
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Yang Y, Zheng SB, Yang Y, Cheng WT, Pan X, Dai QQ, Chen Y, Zhu L, Jiang QW, Zhou YB. The Three Gorges Dam: Does the Flooding Time Determine the Distribution of Schistosome-Transmitting Snails in the Middle and Lower Reaches of the Yangtze River, China? Int J Environ Res Public Health 2018; 15:E1304. [PMID: 29933638 PMCID: PMC6069228 DOI: 10.3390/ijerph15071304] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 06/17/2018] [Accepted: 06/18/2018] [Indexed: 11/16/2022]
Abstract
BACKGROUND Schistosomiasis is one of the most devastating tropical diseases in the world. Oncomelania hupensis is the only intermediate host of Schistosoma japonicum, and its growth and development are sensitive to environmental factors. The Three Gorges Dam has substantially altered the water level in the Yangtze River. This study focused on the impact of the flooding time on the occurrence of Oncomelania snails in Hunan Province, China. METHODS The data regarding Oncomelania snails were collected from the Schistosomiasis Atlas of the People's Republic of China. Air temperature, hours of daylight and relative humidity from 1995 to 2002 were collected from the China Meteorological Data Sharing Service System. The data for rainfall and days inundated with water were collected from the Hunan flood control information system and hydrological stations in Hunan Province. A generalized additive model was used to estimate the impact of these factors on the presence or absence of snails. RESULTS The number of days inundated with water in the areas with snails ranged from 56 to 212 days. However, 82 percent of the areas without snails were inundated with water less than 60 days. The lowest air temperature in a year in the areas without snails ranges from -2.88 °C to -2.10 °C, and the range was from -2.88 °C to -2.34 °C for areas with snails. Annual rainfall in the areas with snails ranged from 989 to 1565 mm, and the range was from 1230 mm to 1647 mm for the areas without snails. The results from the generalized additive model showed that the number of days inundated with water, lowest air temperature in a year, annual rainfall, days of daily rainfall greater than 0.1 mm, and hours of daylight were the factors that significantly affect the occurrence of snails in Hunan Province, China. CONCLUSIONS The number of days inundated with water may be a key factor determining the geographical distribution of Oncomelania snails in Hunan Province and the favorable number of days inundated with water for the survival of snails ranges from about 2 to 7 months.
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Affiliation(s)
- Yu Yang
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong An Road, Xuhui District, Shanghai 200032, China.
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
| | - Sheng-Bang Zheng
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong An Road, Xuhui District, Shanghai 200032, China.
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
| | - Ya Yang
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong An Road, Xuhui District, Shanghai 200032, China.
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
| | - Wan-Ting Cheng
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong An Road, Xuhui District, Shanghai 200032, China.
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
| | - Xiang Pan
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong An Road, Xuhui District, Shanghai 200032, China.
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
| | - Qing-Qing Dai
- Department of Statistics, Oklahoma State University, Stillwater, WA 74078, USA.
| | - Yue Chen
- School of Epidemiology and Public Health, Faculty of Medicine, University of Ottawa, 600 Peter Morand Crescent, Ottawa, ON K1G 5Z3, Canada.
| | - Lan Zhu
- Department of Statistics, Oklahoma State University, Stillwater, WA 74078, USA.
| | - Qing-Wu Jiang
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong An Road, Xuhui District, Shanghai 200032, China.
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
| | - Yi-Biao Zhou
- Fudan University School of Public Health, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Building 8, 130 Dong An Road, Xuhui District, Shanghai 200032, China.
- Fudan University Center for Tropical Disease Research, Building 8, 130 Dong'an Road, Xuhui District, Shanghai 200032, China.
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Ren J, Zheng Z, Li Y, Lv G, Wang Q, Lyu H, Huang C, Liu G, Du C, Mu M, Lei S, Bi S. Remote observation of water clarity patterns in Three Gorges Reservoir and Dongting Lake of China and their probable linkage to the Three Gorges Dam based on Landsat 8 imagery. Sci Total Environ 2018; 625:1554-1566. [PMID: 29996452 DOI: 10.1016/j.scitotenv.2018.01.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 12/27/2017] [Accepted: 01/05/2018] [Indexed: 06/08/2023]
Abstract
The Secchi disk depth (ZSD) plays a critical role in describing water clarity. Several studies have shown linkages between Three Gorges Dam (TGD) and the downstream lacustrine ecosystem in the middle and lower Yangtze River basin. However, the potential influence on the ZSD fluctuation in the entire anthropogenic reservoirs of Three Gorges (ER) and Dongting Lake (DTL) has not been reported, possibly due to technical obstacles in obtaining statistically significant spatial and temporal results. We addressed this challenge by using remote sensing technology: the Landsat 8 Operational Land Imager (OLI). We proposed a new, robust remote-sensing algorithm to estimate ZSD from OLI imagery using red and green band-ratio, leading to MAPE of 21.68% and RMSE of 0.076m for ZSD ranging from 0.1m to 1.05m. After satisfactory image-based validation, the algorithm was implemented on OLI data to derive ZSD patterns over ER and DTL from 2013 to 2017. Several crucial findings can be drawn: 1) Spatial-temporal patterns of ZSD exhibited notable fluctuations over both ER and DTL, and they also demonstrated a significant correlation with each other because of the opposite temporal cycle of ZSD fluctuations between ER and DTL; 2) Temporally, monthly fluctuations of ZSD between ER and DTL had opposite temporal cycles, which was mainly attributed to the surface runoff and sediment discharge driven by the outbound runoff variations of TGD. Spatially, the heterogeneity of the ZSD pattern in ER might have resulted from the different geographical regions being divided by large anthropologic hydrological facilities, such as TGD; 3) The relationship between ZSD and total suspended matter (TSM) showed a significant negative correlation, as did the relationship between ZSD and Kd(490). These findings demonstrate that TSM often plays a principal role in light attenuation of extremely turbid inland waters; 4) An inversed phenomenon of water clarity was observed at the intersection of DTL and the Yangtze River around Chenglingji site (YRAC), which was due to the opposite temporal cycle of ZSD fluctuations between DTL and ER after the impoundment of TGD; and 5) Owing to the analysis of noise-equivalent ZSD, OLI data can be used to derive ZSD, since the imagery uncertainty is 0.07m by means of our band-ratio algorithm, which demonstrates similar results to MODIS. The proposed ZSD-derived algorithm in this study could be suitable for other turbid lakes or reservoirs to formulate related strategies of water quality management in the middle and lower Yangtze River basin, and the unveiled findings here improve our understanding of ZSD spatiotemporal fluctuations in large river-connected lakes, such as Poyang Lake.
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Affiliation(s)
- Jingli Ren
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, College of Geographic Science, Nanjing Normal University, Nanjing 210023, China; Gannan Normal University, Ganzhou 341000, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China.
| | - Zhubin Zheng
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, College of Geographic Science, Nanjing Normal University, Nanjing 210023, China; Gannan Normal University, Ganzhou 341000, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China.
| | - Yunmei Li
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, College of Geographic Science, Nanjing Normal University, Nanjing 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China.
| | - Guonian Lv
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, College of Geographic Science, Nanjing Normal University, Nanjing 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China.
| | - Qiao Wang
- Satellite Environment Application Center, Ministry of Environmental Protection, Beijing 100029, China.
| | - Heng Lyu
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, College of Geographic Science, Nanjing Normal University, Nanjing 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China.
| | - Changchun Huang
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, College of Geographic Science, Nanjing Normal University, Nanjing 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China.
| | - Ge Liu
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, College of Geographic Science, Nanjing Normal University, Nanjing 210023, China.
| | - Chenggong Du
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, College of Geographic Science, Nanjing Normal University, Nanjing 210023, China.
| | - Meng Mu
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, College of Geographic Science, Nanjing Normal University, Nanjing 210023, China.
| | - Shaohua Lei
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, College of Geographic Science, Nanjing Normal University, Nanjing 210023, China.
| | - Shun Bi
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, College of Geographic Science, Nanjing Normal University, Nanjing 210023, China.
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Guo Y, Lai S, Zhang J, Liu Q, Zhang H, Ren Z, Mao D, Luo C, He Y, Wu H, Li G, Ren D, Liu X, Chang Z. Mosquito population dynamics during the construction of Three Gorges Dam in Yangtze River, China. Acta Trop 2018; 182:251-256. [PMID: 29545160 DOI: 10.1016/j.actatropica.2018.03.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 03/02/2018] [Accepted: 03/10/2018] [Indexed: 10/17/2022]
Abstract
BACKGROUND Mosquitoes are responsible for spreading many diseases and their populations are susceptible to environmental changes. The ecosystems in the Three Gorges Region were probably altered because of changes to the environment during the construction of the Three Gorges Dam (TGD), the world's largest hydroelectric dam by generating capacity. METHODS We selected three sites at which to monitor the mosquitoes from 1997 to 2009. We captured adult mosquitoes with battery-powered aspirators fortnightly between May and September of each year in dwellings and sheds. We identified the mosquito species, and examined changes in the species density during the TGD construction. We monitored changes in the species and density of mosquitoes in this area for 13 years during the TGD construction and collected information that could be used to support the control and prevention of mosquito-borne infections. RESULTS We found that the mosquito species composition around the residential areas remained the same, and the density changed gradually during the TGD construction. The changes in the populations tended to be consistent over the years, and the densities were highest in July, and were between 3 and 5 times greater in the sheds than in the dwellings. CONCLUSIONS The mosquito species and populations remained stable during the construction of the TGD. The mosquito density may have increased as the reservoir filled, and may have decreased during the clean-up work. Clean-up work may be an effective way to control mosquitoes and prevent mosquito-borne diseases.
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Hu JY, Xie YH, Tang Y, Li F, Zou YA. Changes of Vegetation Distribution in the East Dongting Lake After the Operation of the Three Gorges Dam, China. Front Plant Sci 2018; 9:582. [PMID: 29765388 PMCID: PMC5938568 DOI: 10.3389/fpls.2018.00582] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 04/13/2018] [Indexed: 05/29/2023]
Abstract
Water regime is regarded as the primary factor influencing the vegetation distribution in natural wetland ecosystems. However, the effect of water regime change induced by large-scale hydraulic engineering on vegetation distribution is still unclear. In this study, multi-temporal TM/ETM+/OLI images and hydrological data from 1995 to 2015 were used to elucidate how the change in water regime influenced the vegetation distribution in the East Dongting Lake (EDTL), especially after the operation of the Three Gorges Dam (TGD) in 2003. Using unsupervised and supervised classification methods, three types of land cover were identified in the study area: Water and Mudflat, Grass, and Reed and Forest. Results showed that the total vegetation area in EDTL increased by approximately 78 km2 during 1995-2015. The areas of Reed and Forest and Grass exhibited a contrasting trend, dramatic increase in Reed and Forest but sharp decrease in Grass, particularly after the operation of TGD. The lowest distribution elevations of Grass and Reed and Forest decreased by 0.61 and 0.52 m, respectively. As a result of water level variation, submergence duration increased at 20-21 m and 28 m elevations (1-13 days), but significantly decreased at 22-27 m and 29-30 m elevations (-3 to -31 days). The submergence duration of Grass and Reed and Forest was 246 and 177 days, respectively. This study indicated that wetland vegetation pattern significantly changed after the operation of TGD, mainly as a result of changes in submergence condition. Submergence duration might be an effective indicator to predict the shift of vegetation distribution in EDTL, and which could provide scientific guidance for vegetation restoration and wetland management in this lake.
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Affiliation(s)
- Jia-Yu Hu
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
- Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yong-Hong Xie
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
- Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
| | - Yue Tang
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
- Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
| | - Feng Li
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
- Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
| | - Ye-Ai Zou
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
- Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
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Zhang J, Li S, Dong R, Jiang C. Physical evolution of the Three Gorges Reservoir using advanced SVM on Landsat images and SRTM DEM data. Environ Sci Pollut Res Int 2018; 25:14911-14918. [PMID: 29546519 DOI: 10.1007/s11356-018-1696-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 03/05/2018] [Indexed: 06/08/2023]
Abstract
The Three Gorges Reservoir (TGR) is one of the largest hydropower reservoirs in the world. However, changes of the important physical characteristics of the reservoir covering pre-, during-, and post- dam have not been well studied. This study analyzed the lengths and water surface areas of the TGR using advanced support vector machine method (SVM) combined Landsat images with the Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM), which showed an increasing trend of lengths and surface areas with variable growth rates from pre-dam period to post-dam period. The highest water level (ca. 171.5 m) was reported in 1st Jan, 2015, with the longest length of 687.8 km and largest water surface area of 1106.2 km2 during the study period. The lowest increasing magnitude of the reservoir length occurred in the first stage (2000-2005) but with the fastest magnitude of water surface area increase. The third stage (2010-2015) showed highest increase magnitude of length and lowest increase magnitude of water surface area. Meanwhile, the increased reservoir areas were mainly from cultivated land, forest land, and building land, with the biggest increase rate of cultivated land regardless of periods. Specifically, cultivated land contributed 39.1-46.0% to increased reservoir water area; the proportions were 22.6-29.6%, 22.1-24.1%, and 5.6-9.4% for forest, building land, and grassland, respectively. The study provides important data for the TGR physical evolution in the Holocene.
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Affiliation(s)
- Jing Zhang
- College of Resources and Environment, Southwest University, Chongqing, 400716, People's Republic of China
- Chongqing Institute of Green and Intelligent Technology (CIGIT), Chinese Academy of Sciences (CAS), 266, Fangzheng Avenue, Shuitu High-tech Park, Beibei, Chongqing, 400714, People's Republic of China
| | - Siyue Li
- Chongqing Institute of Green and Intelligent Technology (CIGIT), Chinese Academy of Sciences (CAS), 266, Fangzheng Avenue, Shuitu High-tech Park, Beibei, Chongqing, 400714, People's Republic of China.
| | - Ruozhu Dong
- Chongqing Institute of Green and Intelligent Technology (CIGIT), Chinese Academy of Sciences (CAS), 266, Fangzheng Avenue, Shuitu High-tech Park, Beibei, Chongqing, 400714, People's Republic of China
| | - Changsheng Jiang
- College of Resources and Environment, Southwest University, Chongqing, 400716, People's Republic of China.
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Shi L, Wang Y, Jia Y, Lu C, Lei G, Wen L. Vegetation Cover Dynamics and Resilience to Climatic and Hydrological Disturbances in Seasonal Floodplain: The Effects of Hydrological Connectivity. Front Plant Sci 2017; 8:2196. [PMID: 29312423 PMCID: PMC5744444 DOI: 10.3389/fpls.2017.02196] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Accepted: 12/13/2017] [Indexed: 06/07/2023]
Abstract
Floodplain wetlands are valuable ecosystems for maintaining biodiversity, but are vulnerable to hydrological modification and climatic extremes. The floodplain wetlands in the middle Yangtze region are biodiversity hotspots, particularly important for wintering migratory waterbirds. In recent years, extremely low winter water level events frequently occurred in the middle Yangtze River. The hydrological droughts greatly impacted the development and distribution of the wet meadows, one of the most important ecological components in the floodplains, which is vital for the survival of many migratory waterbirds wintering in the Yangtze region. To effectively manage the wet meadows, it is critical to pinpoint the drivers for their deterioration. In this study, we assessed the effects of hydrological connectivity on the ecological stability of wet meadow in Poyang Lake for the period of 2000 to 2016. We used the time series of MODIS EVI (Enhanced Vegetation Index) as a proxy for productivity to infer the ecological stability of wet meadows in terms of resistance and resilience. Our results showed that (1) the wet meadows developed in freely connected lakes had significantly higher resilience; (2) wet meadows colonizing controlled lakes had higher resistance to water level anomalies; (3) there was no difference in the resistance to rainfall anomaly between the two types of lakes; (4) the wet meadow in freely connected lakes might approach a tipping point and a regime shift might be imminent. Our findings suggest that adaptive management at regional- (i.e., operation of Three Gorges Dam) and site-scale (e.g., regulating sand mining) are needed to safeguard the long-term ecological stability of the system, which in term has strong implications for local, regional and global biodiversity conservation.
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Affiliation(s)
- Linlu Shi
- School of Nature Conservation, Beijing Forestry University, Beijing, China
| | - Yuyu Wang
- School of Nature Conservation, Beijing Forestry University, Beijing, China
| | - Yifei Jia
- School of Nature Conservation, Beijing Forestry University, Beijing, China
| | - Cai Lu
- School of Nature Conservation, Beijing Forestry University, Beijing, China
| | - Guangchun Lei
- School of Nature Conservation, Beijing Forestry University, Beijing, China
| | - Li Wen
- Water, Wetlands and Coastal Science Branch, NSW Office of Environment and Heritage, Sydney, NSW, Australia
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Su X, Nilsson C, Pilotto F, Liu S, Shi S, Zeng B. Soil erosion and deposition in the new shorelines of the Three Gorges Reservoir. Sci Total Environ 2017; 599-600:1485-1492. [PMID: 28531957 DOI: 10.1016/j.scitotenv.2017.05.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 04/25/2017] [Accepted: 05/01/2017] [Indexed: 06/07/2023]
Abstract
During the last few decades, the construction of storage reservoirs worldwide has led to the formation of many new shorelines in former upland areas. After the formation of such shorelines, a dynamic phase of soil erosion and deposition follows. We explored the factors regulating soil dynamics in the shorelines of the Three Gorges Reservoir (TGR) on the Yangtze River in China. We selected four study sites on the main stem and three on the tributaries in the upstream parts of the reservoir, and evaluated whether the sites close to the backwater tail (the point at which the river meets the reservoir) had more soil deposition than the sites far from the backwater tail. We also tested whether soil erosion differed between the main stem and the tributaries and across shorelines. We found that soil deposition in the new shorelines was higher close to the backwater tail and decreased downstream. Soil erosion was higher in the main stem than in the tributaries and higher at lower compared to higher shoreline altitudes. In the tributaries, erosion did not differ between higher and lower shoreline levels. Erosion increased with increasing fetch length, inundation duration and distance from the backwater tail, and decreased with increasing soil particle fineness. Our results provide a basis for identifying shorelines in need of restorative or protective measures.
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Affiliation(s)
- Xiaolei Su
- Key Laboratory of Eco-Environments in Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources in Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, PR China; Landscape Ecology Group, Department of Ecology and Environmental Science, Umeå University, SE-901 87 Umeå, Sweden.
| | - Christer Nilsson
- Landscape Ecology Group, Department of Ecology and Environmental Science, Umeå University, SE-901 87 Umeå, Sweden.
| | - Francesca Pilotto
- Landscape Ecology Group, Department of Ecology and Environmental Science, Umeå University, SE-901 87 Umeå, Sweden.
| | - Songping Liu
- Key Laboratory of Eco-Environments in Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources in Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, PR China.
| | - Shaohua Shi
- Key Laboratory of Eco-Environments in Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources in Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, PR China.
| | - Bo Zeng
- Key Laboratory of Eco-Environments in Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources in Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, PR China.
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Chen L, Yang Y, Chen J, Gao S, Qi S, Sun C, Shen Z. Spatial-temporal variability and transportation mechanism of polychlorinated biphenyls in the Yangtze River Estuary. Sci Total Environ 2017; 598:12-20. [PMID: 28433818 DOI: 10.1016/j.scitotenv.2017.04.069] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2016] [Revised: 02/27/2017] [Accepted: 04/11/2017] [Indexed: 06/07/2023]
Abstract
Although the variability of polychlorinated biphenyls (PCBs) is strongly dependent on the hydro-sediment pattern, the quantification of this interaction is still not well described, especially for estuary areas. In this study, both chemical analyses and numerical simulation were conducted to explain the temporal-spatial variability and transportation mechanism of PCBs in the Yangtze River Estuary (YRE). The impacts of the upstream Three Gorges Dam (TGD) on estuarine PCBs were also addressed with a simulated scenario. The results showed that the PCBs levels in the YRE were relatively low or moderate and the highest levels were related to the maximum turbidity zone. The spatial variability of PCBs is strongly dependent on the hydrological circulation, which resulted in a declining trend from the inner YRE to the adjacent sea. The seasonal variability of PCBs could be due to the joint influence of the current and the erosion/deposition environment. The opposite temporal trends of the overlaying water and sediment are driven by the seasonal characteristics of hydro-sediment patterns. The simulated results also indicated that the distribution, fluxes and transport ability of PCBs in the South Branch changed as a result of the sediment discharge reduction after construction of the TGD.
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Affiliation(s)
- Lei Chen
- State Key Laboratory of Water Environment, School of Environment, Beijing Normal University, Beijing 100875, PR China.
| | - Ye Yang
- State Key Laboratory of Water Environment, School of Environment, Beijing Normal University, Beijing 100875, PR China; Department of Civil Engineering, The University of Hong Kong, Hong Kong, PR China
| | - Jing Chen
- State Key Laboratory of Water Environment, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Shuohan Gao
- State Key Laboratory of Water Environment, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Shasha Qi
- State Key Laboratory of Water Environment, School of Environment, Beijing Normal University, Beijing 100875, PR China; China Offshore Environmental Services LTD, Beijing, PR China
| | - Cheng Sun
- State Key Laboratory of Water Environment, School of Environment, Beijing Normal University, Beijing 100875, PR China
| | - Zhenyao Shen
- State Key Laboratory of Water Environment, School of Environment, Beijing Normal University, Beijing 100875, PR China.
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Niu B, Wang H, Loáiciga HA, Hong S, Shao W. Temporal variations of groundwater quality in the Western Jianghan Plain, China. Sci Total Environ 2017; 578:542-550. [PMID: 27847182 DOI: 10.1016/j.scitotenv.2016.10.225] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 10/29/2016] [Accepted: 10/30/2016] [Indexed: 06/06/2023]
Abstract
The Western Jianghan Plain (WJHP) lies in the middle reaches of the Yangtze River. It has been impacted by anthropogenic activities during the past decades. The long-term variations of the WJHP's regional aquifer's hydrochemistry and groundwater quality have not been previously assessed. Sixteen physiochemical parameters at 29 monitoring wells within the Western Jianghan Plain were monitored during 1992-2010 and analyzed with multiple approaches. The confined groundwater is predominantly of the HCO3-Ca-Mg type with Cl-, SO42-, NH4-N, and NO3-N showing remarkable spatial variations. Correlation analysis was used to identify the origins and contamination sources of groundwater. The seasonal Mann-Kendall test revealed that pH, NO3-N, and Cl- concentrations at 27, 26 and 15 wells, respectively, exhibited significant increasing trends during 1992-2010. The increase of pH may be attributed to CO2 degassing caused by extensive groundwater extraction. Regional average NO3-N concentrations of groundwater increased coincidently with the increased use of fertilizer, which suggests that nitrate pollution is caused by agricultural activities. Abnormally high values of Cl- and SO42- at some wells were induced by industrial chemicals. In addition, the similarity of the temporal variations of the regional average of pH, NH4-N, and NO3-N concentrations in groundwater with those in the Yangtze River at the outlet of the Three Gorges Reservoir (TGR) suggests that the variations of these parameters in the WJHP is partly due to water storage by the TGR. This study presents an analysis of temporal variations of groundwater quality in the WJHP that reveals a relation between the creation of the TGR and downstream groundwater quality. This paper's findings provide clues for measures that could be taken to protect the groundwater quality of the WJHP's aquifer.
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Affiliation(s)
- Beibei Niu
- School of Resource and Environmental Sciences, Wuhan University, Wuhan 430079, China
| | - Huanhuan Wang
- School of Resource and Environmental Sciences, Wuhan University, Wuhan 430079, China
| | - Hugo A Loáiciga
- Department of Geography, University of California, Santa Barbara, CA 93106, USA
| | - Song Hong
- School of Resource and Environmental Sciences, Wuhan University, Wuhan 430079, China.
| | - Wei Shao
- Scientific Institute of Pearl River Water Resource Protection, Guangzhou 510611, China
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Wen Z, Wu S, Chen J, Lü M. NDVI indicated long-term interannual changes in vegetation activities and their responses to climatic and anthropogenic factors in the Three Gorges Reservoir Region, China. Sci Total Environ 2017; 574:947-959. [PMID: 27665454 DOI: 10.1016/j.scitotenv.2016.09.049] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 09/07/2016] [Accepted: 09/07/2016] [Indexed: 05/22/2023]
Abstract
Natural and social environmental changes in the China's Three Gorges Reservoir Region (TGRR) have received worldwide attention. Identifying interannual changes in vegetation activities in the TGRR is an important task for assessing the impact these changes have on the local ecosystem. We used long-term (1982-2011) satellite-derived Normalized Difference Vegetation Index (NDVI) datasets and climatic and anthropogenic factors to analyze the spatiotemporal patterns of vegetation activities in the TGRR, as well as their links to changes in temperature (TEM), precipitation (PRE), downward radiation (RAD), and anthropogenic activities. At the whole TGRR regional scale, a statistically significant overall uptrend in NDVI variations was observed in 1982-2011. More specifically, there were two distinct periods with different trends split by a breakpoint in 1991: NDVI first sharply increased prior to 1991, and then showed a relatively weak rate of increase after 1991. At the pixel scale, most parts of the TGRR experienced increasing NDVI before the 1990s but different trend change types after the 1990s: trends were positive in forests in the northeastern parts, but negative in farmland in southwest parts of the TGRR. The TEM warming trend was the main climate-related driver of uptrending NDVI variations pre-1990s, and decreasing PRE was the main climate factor (42%) influencing the mid-western farmland areas' NDVI variations post-1990s. We also found that anthropogenic factors such as population density, man-made ecological restoration, and urbanization have notable impacts on the TGRR's NDVI variations. For example, large overall trend slopes in NDVI were more likely to appear in TGRR regions with large fractions of ecological restoration within the last two decades. The findings of this study may help to build a better understanding of the mechanics of NDVI variations in the periods before and during TGDP construction for ongoing ecosystem monitoring and assessment in the post-TGDP period.
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Affiliation(s)
- Zhaofei Wen
- Ecological Process and Reconstruction Research Center of the Three Gorges Ecological Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, No. 266 Fangzheng Avenue, Shuitu Hi-tech Industrial Park, Shuitu Town, Beibei District, Chongqing 400714, China; University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China.
| | - Shengjun Wu
- Ecological Process and Reconstruction Research Center of the Three Gorges Ecological Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, No. 266 Fangzheng Avenue, Shuitu Hi-tech Industrial Park, Shuitu Town, Beibei District, Chongqing 400714, China.
| | - Jilong Chen
- Ecological Process and Reconstruction Research Center of the Three Gorges Ecological Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, No. 266 Fangzheng Avenue, Shuitu Hi-tech Industrial Park, Shuitu Town, Beibei District, Chongqing 400714, China.
| | - Mingquan Lü
- Ecological Process and Reconstruction Research Center of the Three Gorges Ecological Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, No. 266 Fangzheng Avenue, Shuitu Hi-tech Industrial Park, Shuitu Town, Beibei District, Chongqing 400714, China; University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China.
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Chen X, Shen Z, Yang Y. Response of the turbidity maximum zone in the Yangtze River Estuary due to human activities during the dry season. Environ Sci Pollut Res Int 2016; 23:18466-18481. [PMID: 27287491 DOI: 10.1007/s11356-016-6872-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 05/09/2016] [Indexed: 06/06/2023]
Abstract
The interaction between a river and the sea results in a turbidity maximum zone (TMZ) within the estuary, which has a great impact on the local ecosystem. In the Yangtze River Estuary, the magnitude and extent of the TMZ vary with water discharge. In this study, the cumulative human activity altered the water discharge regime from the river to the estuary. In the post-Three Gorges Dam (TGD) period, water discharge increased by 35.10 % at Datong in February compared with that in the pre-TGD period. The effects of water discharge variation on the characteristics of the TMZ were analyzed during spring and neap tidal periods using the three-dimensional environmental fluid dynamic code (EFDC) model. The area of the TMZ decreased by 3.11 and 17.39 % during neap and spring tides, respectively. In addition, the upper limit of the TMZ moved 11.68 km seaward during neap tide, whereas the upper limit of the TMZ in the upstream and downstream areas moved seaward 9.65 and 2.34 km, respectively, during spring tide. These findings suggest that the area and location of the TMZ are more sensitive to upstream runoff during spring tide than during neap tide. These changes in the TMZ will impact the biochemical processes in the Yangtze River Estuary. In the foreseeable future, the distribution characteristic of TMZ will inevitably change due to variations in the Yangtze River discharge resulting from new human activities (i.e., new dams), which are being constructed upstream in the Yangtze River system.
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Affiliation(s)
- Xiaofeng Chen
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
| | - Zhenyao Shen
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China.
| | - Ye Yang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
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Deng K, Yang S, Lian E, Li C, Yang C, Wei H. Three Gorges Dam alters the Changjiang (Yangtze) river water cycle in the dry seasons: Evidence from H-O isotopes. Sci Total Environ 2016; 562:89-97. [PMID: 27096630 DOI: 10.1016/j.scitotenv.2016.03.213] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Revised: 03/29/2016] [Accepted: 03/29/2016] [Indexed: 06/05/2023]
Abstract
As the largest hydropower project in the world, the Three Gorges Dam (TGD) has attracted great concerns in terms of its impact on the Changjiang (Yangtze) River and coastal marine environments. In this study, we measured or collected the H-O isotopic data of river water, groundwater and precipitation in the mid-lower Changjiang catchment during the dry seasons of recent years. The aim was to investigate the changes of river water cycle in response to the impoundment of the TGD. Isotopic evidences suggested that the mid-lower Changjiang river water was ultimately derived from precipitation, but dominated by the mixing of different water masses with variable sources and isotopic signals as well. The isotopic parameter "deuterium excess" (d-excess) yielded large fluctuations along the mid-lower mainstream during the initial stage of the TGD impoundment, which was inherited from the upstream water with inhomogeneous isotopic signals. However, as the reservoir water level rising to the present stage, small variability of d-excess was observed along the mid-lower mainstream. This discrepancy could be explained that the TGD impoundment had significantly altered the water cycle downstream the dam, with the rising water level increasing the residence time and enhancing the mixing of reservoir water derived from upstream. This eventually resulted in the homogenization of reservoir water, and thus small fluctuations of d-excess downstream the dam after the quasi-normal stage (2008 to present). We infer that the retention effect of large reservoirs has greatly buffered the d-excess natural variability of water cycle in large river systems. Nevertheless, more research attention has to be paid to the damming effect on the water cycle in the river, estuarine and coastal areas, especially during the dry seasons.
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Affiliation(s)
- Kai Deng
- School of Ocean and Earth Science, Tongji University, Shanghai, 200092, China; State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China
| | - Shouye Yang
- State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China; Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266061, China.
| | - Ergang Lian
- School of Ocean and Earth Science, Tongji University, Shanghai, 200092, China; State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China
| | - Chao Li
- State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China
| | - Chengfan Yang
- School of Ocean and Earth Science, Tongji University, Shanghai, 200092, China; State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China
| | - Hailun Wei
- School of Ocean and Earth Science, Tongji University, Shanghai, 200092, China; State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China
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Zhou YB, Liang S, Chen Y, Jiang QW. The Three Gorges Dam: Does it accelerate or delay the progress towards eliminating transmission of schistosomiasis in China? Infect Dis Poverty 2016; 5:63. [PMID: 27377962 PMCID: PMC4932735 DOI: 10.1186/s40249-016-0156-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 06/17/2016] [Indexed: 11/29/2022] Open
Abstract
The Three Gorges Dam, located in the largest endemic area of schistosomiasis in China, is one of the world’s largest hydroelectric projects to date. Some large-scale hydro projects have resulted in schistosomiasis emergence or re-emergence. Therefore, the dam’s potential impact on the transmission of Schistosoma japonicum has raised concerns from medical researchers worldwide. A systematic literature review, coupled with an analysis of data on the water level and snail density in the Yangtze River was conducted to assess the impact of the dam on schistosomiasis transmission after more than 10 years of operation. The dam has significantly altered the water levels in the Yangtze River according to different seasons. These changes directly impact the ecology of the schistosome snail host. Due to the dam, there has been a reduction in the density of Oncomelania snails and/or changes in the distribution of snails. The prevalence of infection with S. japonicum has decreased in the downstream areas of the dam, including in the Dongting and Poyang Lakes. The prevalence of infection with S. japonicum in humans has decreased from 6.80 % in 2002 (before the dam began operating) to 0.50 % in 2012, and the number of people infected with S. japonicum have decreased from 94 208 in 2002 to 59 200 in 2011 in the Poyang Lake region. The presence of the dam does not seem to affect snail breeding or the prevalence of schistosomiasis in the Three Gorges Reservoir. Overall, the Three Gorges Dam has significantly contributed to changes in hydrology after more than 10 years of the dam operating. The changes caused by the dam, together with integrated control of schistosomiasis, might be accelerating the progress towards eliminating the transmission of S. japonicum in the middle and lower reaches of the Yangtze River. Despite the positive effect the dam is having in controlling S. japonicum transmission, continued surveillance is required to monitor the future ecological impacts of the dam over the long term.
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Affiliation(s)
- Yi-Biao Zhou
- Department of Epidemiology, School of Public Health, Fudan University, 138 Yi Xue Yuan Road, Shanghai, 200032, China. .,Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, 138 Yi Xue Yuan Road, Shanghai, 200032, China. .,Center for Tropical Disease Research, Fudan University, 138 Yi Xue Yuan Road, Shanghai, 200032, China.
| | - Song Liang
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, Gainesville, FL, USA.,Emerging Pathogens Institute, University of Florida, Gainesville, FL, USA
| | - Yue Chen
- School of Epidemiology, Public Health and Preventive Medicine, Faculty of Medicine, University of Ottawa, 451 Smyth Road, Ottawa, Ontario, Canada
| | - Qing-Wu Jiang
- Department of Epidemiology, School of Public Health, Fudan University, 138 Yi Xue Yuan Road, Shanghai, 200032, China. .,Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, 138 Yi Xue Yuan Road, Shanghai, 200032, China. .,Center for Tropical Disease Research, Fudan University, 138 Yi Xue Yuan Road, Shanghai, 200032, China.
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Tang Q, Bao Y, He X, Fu B, Collins AL, Zhang X. Flow regulation manipulates contemporary seasonal sedimentary dynamics in the reservoir fluctuation zone of the Three Gorges Reservoir, China. Sci Total Environ 2016; 548-549:410-420. [PMID: 26803740 DOI: 10.1016/j.scitotenv.2015.12.158] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 12/29/2015] [Accepted: 12/30/2015] [Indexed: 06/05/2023]
Abstract
Since the launch of the Three Gorges Dam on the Yangtze River, a distinctive reservoir fluctuation zone has been created and significantly modified by regular dam operations. Sediment redistribution within this artificial landscape differs substantially from that in natural fluvial riparian zones, due to a specific hydrological regime comprising steps of water impoundment with increasing magnitudes and seasonal water level fluctuation holding a range of sediment fluxes. This study reinterpreted post-dam sedimentary dynamics in the reservoir fluctuation zone by stratigraphy determination of a 345-cm long sediment core, and related it to impact of the hydrological regime. Seasonality in absolute grain-size composition of suspended sediment was applied as a methodological basis for stratigraphic differentiation. Sedimentary laminations with relatively higher proportions of sandy fractions were ascribed to sedimentation during the dry season when proximal subsurface bank erosion dominates source contributions, while stratigraphy with a lower proportion of sandy fractions is possibly contributed by sedimentation during the wet season when distal upstream surface erosion prevails. Chronology determination revealed non-linear and high annual sedimentation rates ranging from 21.7 to 152.1cm/yr. Although channel geomorphology may primarily determine the spatial extent of sedimentation, seasonal sedimentary dynamics was predominantly governed by the frequency, magnitude, and duration of flooding. Summer inundation by natural floods with enhanced sediment loads produced from upstream basins induced higher sedimentation rates than water impoundment during the dry season when distal sediment supply was limited. We thus conclude that flow regulation manipulates contemporary seasonal sedimentary dynamics in the reservoir fluctuation zone, though little impact on total sediment retention rate was detected. Ongoing reductions in flow and sediment supply under human disturbance may have profound implications in affecting sedimentary equilibrium in the reservoir fluctuation zone. The results herein provide insights of how big dams have disrupted the sediment conveyance processes of large scale fluvial systems.
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Affiliation(s)
- Qiang Tang
- Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China; State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yuhai Bao
- Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
| | - Xiubin He
- Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China.
| | - Bojie Fu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Adrian L Collins
- Sustainable Soils and Grassland Systems Department, Rothamsted Research, North Wyke, Okehampton EX20 2SB, UK
| | - Xinbao Zhang
- Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
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Li Z, Nie X, Zhang Y, Huang J, Huang B, Zeng G. Assessing the influence of water level on schistosomiasis in Dongting Lake region before and after the construction of Three Gorges Dam. Environ Monit Assess 2016; 188:28. [PMID: 26661964 DOI: 10.1007/s10661-015-5033-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 12/02/2015] [Indexed: 05/15/2023]
Abstract
Schistosomiasis is a severe public health problem in the Dongting Lake region, and its distribution, prevalence, and intensity of infection are particularly sensitive to environmental changes. In this study, the human and bovine schistosomiasis variations in the Dongting Lake region were studied from 1996 to 2010, and the relationships between schistosomiasis and water level were examined. Furthermore, based on these results, the potential effects of the Three Gorges Dam (TGD) on schistosomiasis were investigated. Results showed an increase in human schistosomiasis and in the scope of seriously affected regions, along with a decrease in bovine schistosomiasis. Human schistosomiasis was negatively correlated with water level during wet season (from May to October), particularly the average water level in October. This finding indicated that the decreasing water level may be highly related to the increasing of human schistosomiasis in the Dongting Lake region. Based on this result and the variation of schistosomiasis before and after the construction and operation of TGD, the impoundment of the Three Gorges reservoir is believed to decrease the water level and increase the contact between people and schistosomiasis. Therefore, the TGD, which is operated by regulating water and scheduling water operations, is not good for the control of human schistosomiasis in the Dongting Lake region. Although the extent of the influence of the TGD on schistosomiasis remains unclear, the influence of the TGD on preventing and controlling schistosomiasis should not be ignored.
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Affiliation(s)
- Zhongwu Li
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, People's Republic of China.
- Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, People's Republic of China.
| | - Xiaodong Nie
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, People's Republic of China
- Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, People's Republic of China
| | - Yan Zhang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, People's Republic of China
- Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, People's Republic of China
| | - Jinquan Huang
- Department of Soil and Water Conservation, Yangtze River Scientific research Institute, Wuhan, 430010, People's Republic of China
| | - Bin Huang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, People's Republic of China
- Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, People's Republic of China
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, People's Republic of China
- Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, People's Republic of China
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Affiliation(s)
- Paul K S Lam
- State Key Laboratory in Marine Pollution, Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
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