Ecological Health Assessment of Typical Deep Pool Habitat in the Upper Reaches of the Yangtze River.

As an important theory of water ecological protection and restoration, fish habitat health assessment has always been the focus of research, but there is a lack of in-depth research on quantitative comprehensive assessment. By taking 5 typical deep-pool habitats in the upper reaches of the Yangtze River as examples, this paper establishes a quantitative evaluation system of fish habitat health status. Based on the habitat health assessment (primary index) of the typical deep pool in the upper reaches of the Yangtze River, the study is divided into habitat environment and habitat function (secondary index), covering 5 tertiary indexes (water quality, biological environment, hydrological environment, fish resource status, habitat quality) and 29 quaternary indexes. A mathematical model for comprehensive assessment of habitat health is built based on entropy weight method. The typical habitat health status is characterized by comprehensive health indicator (p), and the health status of the habitat is evaluated comprehensively. The results show that one of typical deep pool habitatin the upper reaches of Yangtze River is in a very healthy state with a health grade of I . The evaluation of the three places is II level, in the health state. A site is rated as level III, in the sub-health state, and no healthy or poor tide point. On the whole, the typical habitat in the upper reaches of the Yangtze River is basically in health state, and shows strong spatial heterogeneity. The evaluation results objectively reflect the health status of the typical habitat in the upper reaches of the Yangtze River to a certain extent. Finally, according to the scoring grades, the urgent problems in the fish habitat ecosystem in the upper reaches of the Yangtze River are discussed, and the countermeasures and suggestions for habitat restoration are put forward. [ABSTRACT FROM AUTHOR]