SHENG Jiani, LI Nian, CAI Yuanyuan, et al. Source-sink mechanisms of heavy metals in net deposited sediments in water-level fluctuation zone of Three Gorges Reservoir Area[J]. Journal of Soil and Water Conservation, 2026, 40(4):386-395.
SHENG Jiani, LI Nian, CAI Yuanyuan, et al. Source-sink mechanisms of heavy metals in net deposited sediments in water-level fluctuation zone of Three Gorges Reservoir Area[J]. Journal of Soil and Water Conservation, 2026, 40(4):386-395.DOI: 10.13870/j.cnki.stbcxb.2026.04.036. CSTR: 32310.14.stbcxb.2026.04.036.
Source-Sink Mechanisms of Heavy Metals in Net Deposited Sediments in Water-Level Fluctuation Zone of Three Gorges Reservoir Area
To clarify the newly introduced pollution fingerprints during a single hydrological regulation cycle in the Three Gorges Reservoir Area, and accurately identify the sources and driving mechanisms of heavy metals under different hydrodynamic conditions.
Methods
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In the typical riparian water-level fluctuation zones (Shibaozhai, Guojiaba, and Xiangxi River) in the middle and lower reaches of the Three Gorges Reservoir Area, intact net-deposited sediments across a complete hydrological cycle were collected using in-situ sediment columns. The potential ecological risk index (PERI), canonical correspondence analysis (CCA), and positive matrix factorization (PMF) were applied to systematically analyze the pollution characteristics, sources, and environmental driving mechanisms of heavy metals (As, Cd, Cr, Cu, Mn, Ni, Pb, Zn).
Results
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1) Pollution characteristics: Cd was the primary pollution factor, with its average content significantly higher than the background value of the reservoir area. The ecological risk level in the reservoir center was significantly higher than that in the reservoir head, and the high-risk hotspots were concentrated in the deep flooding zone (145~155 m). 2) Driving mechanisms: Flooding duration explained 54.5% of the variance in heavy metals, serving as the primary driving factor. The "hydraulic sorting effect" driven by long-term flooding facilitated the preferential adsorption and accumulation of fine particles and heavy metals in low-elevation areas. 3) Source apportionment: The PMF model identified three pollution sources, namely traffic/industrial sources (mainly contributing to Cd and Pb), agricultural/mixed sources (mainly contributing to As, Cu, and Ni), and natural sources (mainly contributing to Mn). Among these, the contribution rate of industrial sources to Cd was nearly 100%.
Conclusion
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It is confirmed that the net-deposited sediments can effectively retrace short-term pollution inputs in the reservoir area and confirm the interception effect of the midstream backwater fluctuation zone as a "sediment filter" and its vertical enrichment mechanism, thereby providing a scientific basis for the refined management and zoned prevention and control of heavy metal pollution in the water-level fluctuation zone of the Three Gorges Reservoir Area.
Tang Qiang , He Xiubin , Bao Yuhai , et al . Sedimentation process of typical riparian zones in the main stream of the Three Gorges Reservoir [J]. Science and Technology Review , 2014 , 32 ( 24 ): 73 - 77 .
Zhang Lei , Guan Jianchao , Guo Qingchao , et al . A review of hydrological and sediment research in the Three Gorges based on bibliometrics: Context evolution and frontier prospects [J]. Three Gorges Ecological Environment Monitoring , 2025 , 10 ( 3 ): 78 - 90 .
Zeng Huan . Fate and regulation mechanism of heavy metals in soil-plant system of Poyang Lake riparian zone wetland [D]. Nanchang : Jiangxi Normal University , 2025 .
Xiong Runguang . Spatial differentiation, pollution assessment and source analysis of heavy metals in soils of riparian zones in the Three Gorges Reservoir area [D]. Huangshi, Hubei : Hubei Normal University , 2023 .
Zhang Siyuan . Occurrence characteristics, source analysis and mass load of organic tracers and trace elements in sediments of riparian zones in the Three Gorges Reservoir area [D]. Chongqing : Chongqing University , 2022 .
Zhang Zhiyong , Wan Chengyan , Hu Hongqing , et al . Fraction distribution characteristics and risk assessment of heavy metals in surface sediments of the middle and upper reaches of the Yangtze River [J]. Environmental Science , 2023 , 44 ( 2 ): 770 - 780 .
Ren Hongrui . Temporal and spatial variation characteristics of cultivated land resources and cultivated land pressure in the Three Gorges Reservoir area [J]. Journal of Chongqing Normal University (Natural Science Edition) , 2010 , 27 ( 5 ): 23 - 27 .
Lin Li , Dong Lei , Pan Xiong , et al . Changes of water and sediment and their eco-environmental response characteristics in the Three Gorges Reservoir area after impoundment [J]. Journal of Lake Sciences , 2023 , 35 ( 2 ): 411 - 422 .
State environmental protection administration of China . solid waste-determination of metals-inductively coupled plasma mass spectrometry (ICP-MS) : HJ 766—2015 [S]. Beijing : China Environmental Science Press , 2015 .
Wang Linhua , Yu Mengxiao , Wang Senhao , et al . Effects of coral sand profile structure and hydrological conditions on slope hydrology and sand transport [J]. Journal of Soil and Water Conservation , 2025 , 39 ( 5 ): 179 - 187 .
Wang Jie , Zheng Hao , Li Zihan , et al . Effects of soil texture on effective mixing depth and solute loss [J]. Journal of Soil and Water Conservation , 2025 , 39 ( 2 ): 65 - 73 .
Hakanson L . An ecological risk index for aquatic pollution control [J]. Water Research , 1980 , 14 ( 8 ): 975 - 1001 .
Dong Ying , Yang Jie , Wu Xijun , et al . Pollution characteristics and source analysis of desert freshwater lakes based on APCS-MLR and PMF models [J]. Environmental Chemistry , 2026 , 45 ( 2 ): 649 - 662 .
Tang Jiang , Zhong Yuanping , Wang Li . Study on background values of heavy metals in soils of the Three Gorges Reservoir area [J]. Chinese Journal of Eco Agriculture , 2008 , 16 ( 4 ): 848 - 852 .
LI Ying . Plankton community structure and aquatic ecological health assessment of typical aquatic ecosystems in Jinan [D]. Dalian, Liaoning : Dalian Ocean University , 2022 .
Liu Shangwu , Li Danxu , Liu Dechun , et al . Characteristics of sedimentation and sediment trapping efficiency in the Three Gorges Reservoir, China [J]. Catena , 2022 , 208 : e105715 .
Jin Zhouwu , Feng Le , Liu Yujiao , et al . Impact of dam construction on sediment transport capacity: A case study of the Three Gorges Reservoir [J]. Hydrological Processes , 2024 , 38 ( 4 ): e15147 .
Tang Qiang , Bao Yuhai , He Xiubin , et al . Sedimentation and associated trace metal enrichment in the riparian zone of the Three Gorges Reservoir, China [J]. Science of the Total Environment , 2014 , 479-480 : 258 - 266 .
Wang Yongyan , Wen Anbang , Shi Zhonglin , et al . Characteristics of sediment and heavy metal assessment in riparian zones of typical tributary bays in the Three Gorges Reservoir area [J]. Environmental Science , 2016 , 37 ( 3 ): 935 - 941 .
Wang Yechun , Lei Bo , Yang Sanming , et al . Heavy metal contents and pollution assessment of soils at different water levels in riparian zones of the Three Gorges Reservoir area [J]. Environmental Science , 2012 , 33 ( 2 ): 612 - 617 .
Xie Yuhang . Study on sediment sources of typical riparian zones in the main and tributary streams of the Three Gorges Reservoir [D]. Wuhan : Huazhong Agricultural University , 2024 .
CHEN Musong , DING Shiming , LI Cai , et al . High cadmium pollution from sediments in a eutrophic lake caused by dissolved organic matter complexation and reduction of manganese oxide [J]. Water Research , 2021 , 190 : e116711 .
Lan Qiaojuan . Study on migration and transformation mechanisms of typical heavy metals in sediments of riparian zones in the Three Gorges Reservoir area [D]. Chongqing : Chongqing Three Gorges University , 2019 .
Gan Tingting , Zhao Nanjing , Yin Gaofang , et al . Pollution status and prevention suggestions of heavy metals in agricultural soils in the Yangtze River Delta [J]. Engineering Sciences in China , 2021 , 23 ( 1 ): 174 - 184 .
Mei Man , Zhang Jun , Lei Junsheng , et al . Pollution assessment and source analysis of heavy metals in alluvial soils of Anhui section of the Yangtze River [J]. Environmental Ecology , 2025 , 7 ( 2 ): 31 - 39 .
Liu Yue , Li Fuxiang , Cheng Yan , et al . Comparative study on heavy metal deposition records between Yalu River estuary and middle upper reaches [J]. Marine Development and Management , 2025 , 42 ( 8 ): 94 - 108 .
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