Quantitative research on the water ecological environment of dam-controlled rivers: case study of the Shaying River,China

ABSTRACT

To solve the contradiction between regulation and protection of the water ecological environment in a dam-controlled river, it is necessary to identify the main influencing factors of that environment and the interactions between the water quantity, quality and ecology. In this paper, the redundancy analysis (RDA) technique is used to identify the key influencing factors of water eco-environment in the Shaying River, China. The multivariate nonlinear quantization method is used to quantify the interactive relationship between water quantity, water quality and water ecology, and a quantitative model of the dam-controlled river eco-environment is constructed. The results show the relative importance of the various environmental factors. The Shannon-Wiener diversity index is used to assess phytoplankton, zooplankton and benthos (P-SWI, Z-SWI and B-SWI, respectively). The R² of the quantization models for P-SWI, Z-SWI and B-SWI in the fitting phase were 0.81, 0.72 and 0.66, respectively, and, in the validation phase, they were 0.36, 0.31 and 0.41, respectively. The results of this study can provide reference and support for the environmental regulation of dam-controlled rivers.