Establishment Of Water Ecological Health Evaluation System Of Guizhou Plateau River And Its Application In Nanming River

In this paper,the water ecosystem of Nanming River in Guizhou Plateau is taken as the research object.According to the existing research results and the collected index data,the alternative indexes are screened,and the principal component analysis method is used to screen the alternative indexes.The evaluation index system of water ecological health in Nanming River of Guizhou Plateau is constructed.Based on this,the characteristics of phytoplankton community in Nanming River,the dominance index Berger-Parker phytoplankton,and the comprehensive pollution index of water quality in Nanming River were analyzed.The reliability of water ecological health evaluation results of Nanming River in Guizhou plateau was analyzed.The main conclusions are as follows:（1）Conduct a field survey on Nanming River in July,August and November 2020,select 30 candidate indicators based on the collected data,and select 12 indicators through discriminative analysis of indicators,characteristic contribution rate and independence analysis Evaluation indicators,namely,flow process variation（FD）,ecological flow assurance（EF）,riparian zone stability（BSK）,artificial disturbance（RD）,total nitrogen（TN）,total phosphorus（TP）,permanganic acid Salt Index(COD_Mn),Dissolved Oxygen（DO）,Heavy Metal Lead（Pb）,Phytoplankton Shannon-Wiener Diversity Index（P-H）,Zooplankton Shannon-Wiener Diversity Index（Z-H）and Public Satisfaction（SS）.（2）The comprehensive health index is used to evaluate the health of the Nanming River aquatic ecology in the Guizhou Plateau.The comprehensive health index of Nanminghe in July,August and November of 2020 were 60.96,61.74 and 63.03,respectively,and the results of the 3assessments were all healthy.July 2020 S12（Guanzhou Bridge）,S13（Hongyan Bridge）,S14（Happy Mushroom City）,S17（Xinzhuang Sewage Treatment Plant）,S18（Intersection of Nanming River and Toubao River）,S20（Namming River and Baishui River）River intersection)health status is sub-healthy;August 2020 S5（Shanshui Qiancheng）,S11（Jiaxiu Building）,S12（Guanzhou Bridge）,S13（Hongyan Bridge）,S14（Happy Mushroom City）,S18（Intersection of Nanming River and Toubao River）,S20（Intersection of Nanming River and Baishui River）health status is sub-healthy;November 2020 S7（Qingshan Sewage Treatment Plant）,S8（Intersection of Nanming River and Xiaoche River）,S12（Guanzhou Bridge）,S13（Hongyan Bridge）,S14（Happy Mushroom City）health status is sub-healthy.（3）By comparing the comprehensive health index with the Berger-Parker dominance index of phytoplankton and the comprehensive water quality pollution index,from the comprehensive health index and the phytoplankton Berger-Parker dominance index change trend and the comprehensive health index and the comprehensive water pollution index The change trend analysis shows that the water ecological health evaluation index system of the Nanming River in Guizhou Plateau constructed in this paper is reliable in analyzing the health results of the Nanming River.