Author(s): Lei-Lei Qin; Zhong-Luan Yan; Er-Peng Wang; Jia Li; Xian-Yong Dong
Linked Author(s): Jia LI
Keywords: Xiluodu Hydropower reservoir; Xiangjiaba Hydropower reservoir; Stoplog gate; Water temperature
Abstract: With the operation of the Jinshajiang cascade hydropower station, thermal regime of rivers occurs as a result of anthropogenic perturbations, the effect of cascade operation on the thermal regime of reservoirs and downstream are gradually revealed. In this paper we collected historical statistical data of river water temperature, to clarify the temporal and spatial variation of water temperature affected by the development of hydropower in the lower reaches of Jinsha River mainstream. Then we analyzed the vertical temperature profiles in reservoirs and thermal regime in the downstream during ecological regulation. The result showed that the water temperature at the Baihetan hydrological station appeared colder than the natural during spring and summer, warmer than the natural during autumn and winter in 2016. There is an accumulated thermal effect due cascade hydropower dams. The phase of released water was more delayed than natural, and the annual variation was more flattened. During the ecological regulation, there are a significant temperature stratification in Xiluodu and Xiangjiaba reservoirs. Water temperature of intake elevation was increased 0.5℃, the water temperature of tributary Min River is higher than mainstream, which can ease the impact of cold water release. The water temperature of protection river reach can meet the requirements for fish breeding. The research results can provide scientific basis and experience for the operation and management of the ecological regulation of large-scale water conservancy and hydropower projects.
Year: 2018