Research On The Ecological Impact Assessment Method Of Typical Inland Waterway Project

With the rapid development of China’s water transport industry,in order to meet the growing demand for transportation,the transportation department has continued to carry out the construction of inland waterway projects in recent years.Usually the construction process will affect the ecological environment,so it is necessary to study the ecological impact assessment method of the waterway construction process.This paper analyzes the domestic and foreign ecological environment impact assessment methods,draws on the methods and principles of domestic and foreign waterway engineering environmental impact assessment,and summarizes the typical waterway engineering ecological environment impact assessment methods.The section from Xijin Junction to Guigang junction in Yujiang River Basin is taken as the research area,and studies the ecological environment impact assessment method from two aspects:terrestrial ecology and aquatic ecology.In the assessment of terrestrial ecosystems,the Environmental Index（EI）is used to assess the quality of the ecological environment of segmented objects.The index consists of biological abundance index,vegetation coverage index,water network density index,land stress index,It is composed of pollution load index and environmental restriction index.The EI values before and after the project construction are 63.56 and 63.20,respectively,indicating that the terrestrial ecological environment before and after the project construction was good.After completion,the quality of the terrestrial ecological environment has decreased,but there has been no significant change.The assessment results show that the impact of the project construction on terrestrial vegetation is mainly reflected in the destruction of the original surface vegetation by the land occupied by the facility and the reduction of regional biomass.Due to the migratory ability of animals,the project construction has little impact on wildlife.The aquatic ecosystem is divided into two parts:water quality evaluation and biological evaluation.The water quality evaluation adopts the comprehensive quality index to comprehensively evaluate the five water quality indicators of p H,COD_Cr,BOD₅,total phosphorus and ammonia nitrogen.The results show that the comprehensive water quality index before and after construction decreased from 0.37.Up to 0.29,according to the grading standard before and after construction,there was mild pollution;the biological evaluation used Shannon index,evenness index and Simpson diversity index to evaluate phytoplankton and zooplankton respectively.The results showed that the Shannon index of phytoplankton increased from 2.095 to 2.144,phytoplankton evenness index increased from 0.342 to 0.415,phytoplankton Simpson diversity index decreased from 0.719 to 0.691;zooplankton Shannon index increased from 1.920 to 2.810,zooplankton evenness index increased from 0.335 to 0.573,zooplankton Simpson diversity index The index rose to 0.833 from 0.720.The results show that the long-term impact of waterway construction on water quality is less.According to the diversity index data,the pollution levels before and after construction are all slightly polluted.According to the uniformity index,both before and after construction are moderately polluted.Finally,the entropy method was used to measure p H,SS,COD_Cr,BOD₅,total phosphorus,ammonia nitrogen,phytoplankton Shannon index,phytoplankton evenness index,phytoplankton Simpson diversity index,zooplankton Shannon index,zooplankton evenness index and the zooplankton Simpson Diversity Index was weighted and an overall aquatic ecosystem health index was calculated.The comprehensive health index of aquatic ecosystems before and after construction was 53.13 and 46.87,respectively.According to the classification standard of habitat health index,both before and after construction were at a moderate level,but the comprehensive health index decreased slightly after construction.The results show that the construction project has a certain negative impact on aquatic ecology,but the impact is not significant.Judging from the evaluation results,the project construction has a certain degree of negative impact on the ecological environment of the flight segment,but the impact is less.According to the evaluation results,this study puts forward the following suggestions:in terms of terrestrial ecology,the ecological slope protection plant adopts the method of combining bermudagrass herb and rose bush;in terms of aquatic ecology,it is recommended to reduce the damage to fish caused by engineering construction and strengthen fishery management.This study summarizes and establishes an ecological impact assessment method for inland waterway regulation projects in the country,which provides a reference for the ecological impact assessment of other inland waterway regulation projects.