Effects of water level fluctuation on thermal stratification in a typical tributary bay of Three Gorges Reservoir, China

Juxiang Jin; Scott A Wells; Defu Liu; Guolu Yang; Senlin Zhu; Jun Ma; Zhengjian Yang

doi:10.7717/peerj.6925

Effects of water level fluctuation on thermal stratification in a typical tributary bay of Three Gorges Reservoir, China

PeerJ. 2019 May 15:7:e6925. doi: 10.7717/peerj.6925. eCollection 2019.

Authors

Juxiang Jin¹, Scott A Wells², Defu Liu³, Guolu Yang¹, Senlin Zhu⁴, Jun Ma³, Zhengjian Yang³

Affiliations

¹ School of Water Resources and Hydropower Engineering, Wuhan University, Wuhan, Hubei, China.
² Department of Civil and Environmental Engineering, Portland State University, Portland, OR, USA.
³ Hubei Key Laboratory of Ecological Restoration of River-Lakes and Algal Utilization, Hubei University of Technology, Wuhan, Hubei, China.
⁴ State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing, China.

Abstract

Xiangxi River is a typical tributary of Three Gorges Reservoir (TGR) in China. Based on field observations in 2010, thermal stratification was significant in most months of the year. Through field data analysis and numerical simulations, the seasonal and spatial variation of thermal stratification as related to the impact of the operation of TGR were investigated. Thermal stratification was most pronounced from April to September in the Xiangxi River tributary. Air temperature (AT) and water level (WL) were the two dominant variables impacting thermal stratification. AT affected the surface water temperature promoting the formation of thermal stratification, and high WLs in TGR deepened the thermocline depth and thermocline bottom depth. These results provide a preliminary description of the seasonal variation and spatial distribution of thermal stratification, which is important for better understanding how thermal stratification affects algae blooms in Xiangxi River.

Keywords: CE-QUAL-W2; Thermal stratification; Three Gorges Reservoir; Water level fluctuation; Xiangxi River.

Grants and funding

This work was supported financially by the National Natural Science Foundation of China (91647207), the National Natural Science Foundation of China (51709096), the National Natural Science Foundation of China (51879099), the Natural Science and Technology Major Special Program of China (2016YFC0402204) and the Natural Science and Technology Major Special Program of China (2016YFC0401702). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.