Investigation of the methodology for determining the ecological benchmark in water ecological health assessment

Abstract

[Objective] Water ecological health assessment is an important way of integrating water resources, water environment and water ecosystem management, often through a series of quantitative indicators to assess the state of water ecosystems. Benchmarks provide a “baseline” for changes in ecological health. The identification of ecological benchmarks that are both scientifically sound and reasonable often considers the ecological desirability of water ecosystems in conjunction with human management needs, with the aim of improving the accuracy of water ecological health assessments.[Methods] From the concept of baseline and the four forms of references, several typical baseline determination method are sorted out, and their respective characteristics, advantages and disadvantages are compared. It combs, summarizes and analyzes the determination method of benchmarks for three major categories of indicators: physical habitat, physical and chemical properties, and aquatic organisms.[Results] The practical application of ecological benchmarking in different aquatic ecosystems in the Yangtze River Basin is emphasized, and the similarities and differences of the water ecological assessment related standards/by-laws issued by different management departments in China are compared. Difficulties in ecological baseline determination are discussed, such as the selection of reference sites, the selection of monitoring indicators, the accumulation of monitoring data, the regional variability of baseline determination and innovative method of determination.[Conclusion] The ecological benchmark determination method are relatively complex, and have not yet formed a unified specification, future research should be combined with advanced technologies such as big data and artificial intelligence, in order to achieve scientific, accurate and differentiated formulation, and to provide reference and technical support for the evaluation of water ecological health in China.

Keywords

water ecological health / ecological benchmark / reference site method / predictive model method / influencing factors