Solute transport characteristics at the lakebed sediment-water interface due to multiple influences of dual seasonal lakes

Siyi Zhang; Chen Chen; Hongwu Tang; Guangqiu Jin; Bo Zhou; Haiyu Yuan; Hexiang Chen

doi:10.1016/j.scitotenv.2024.170284

Solute transport characteristics at the lakebed sediment-water interface due to multiple influences of dual seasonal lakes

Sci Total Environ. 2024 Mar 25:918:170284. doi: 10.1016/j.scitotenv.2024.170284. Epub 2024 Jan 22.

Authors

Siyi Zhang¹, Chen Chen², Hongwu Tang³, Guangqiu Jin⁴, Bo Zhou⁵, Haiyu Yuan¹, Hexiang Chen¹

Affiliations

¹ The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing, China; College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing, China.
² State Grid Zhejiang Electric Power Co., Ltd, Hangzhou, China.
³ The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing, China; Yangtze Institude for Conservation and Development, Hohai University, Nanjing, China; Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources, Hohai University, Nanjing, China.
⁴ The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing, China; Yangtze Institude for Conservation and Development, Hohai University, Nanjing, China; Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources, Hohai University, Nanjing, China. Electronic address: jingq@hhu.edu.cn.
⁵ School of Naval Architecture and Ocean Engineering, Dalian University of Technology, Dalian, China.

PMID: 38266724
DOI: 10.1016/j.scitotenv.2024.170284

Abstract

Multiple coexisting seasonal lakes are observed in the Poyang Lake basin. The interaction between surface water and groundwater, along with solute transport at the sediment-water interface (SWI), plays a crucial role in material cycling within the Poyang Lake ecosystem. However, the mechanisms governing how the relative positions of these lakes influence solute transport at the SWI remain unclear. This study employs indoor experiments and simulations based on real topography to investigate how the separation distance and elevation differences between two seasonal lakes, termed "lake A" (situated farther from the main lake) and "lake B" (closer to the main lake), affect solute transport. Findings highlight a distinct recharge pattern from lake A to lake B and the main lake during periodic water level fluctuations. A reduced distance between dual seasonal lakes results in a diminished water level drop in lake B during dry seasons. Proximity allows lake A to contribute more solutes to the main lake while promoting solute transport from lake B to the main lake, increasing the pore water recharge flux to overlying water in lake B. In cases where the separation distance has insufficient impact on water levels, the speed of pore water flow in this area inversely correlates with the distance between dual lakes. Reducing the distance intensifies solute transport into the bottom of lake A. Lower the elevation of lake B increases the water level difference between dual seasonal lakes, curtailing pollution within the lakebed. Elevating lake B forms hydrological isolation and more severe pollution of the lakebed. Solutes predominantly transport between lake B and the main lake, with pollution spreading to the lakebed of lake A and transitioning to downward diffusion over time. This research provides valuable insights for the hydraulic regulation of seasonal lakes and holds significance for the ecological restoration of Poyang Lake.

Keywords: Horizontal separation distance; Relative elevation; Seasonal lake; Sediment-water interface; Solute transport.