Method of using benthic organisms to evaluate ecological toxicity effects of tailwater replenished rivers

The present invention involves the technical field of river ecosystem risk evaluation, and provides a method of using benthic organisms to evaluate ecological toxicity effects of 5 tailwater replenished rivers. By first evaluating evaluation scopes of rivers, each river to be evaluated is divided into multiple evaluated river segments, a corresponding number of monitoring points are set up in each evaluated river segment, benthic organisms are used as evaluation species to conduct on-site surveys at each monitoring point, by combining environmental DNA technology, multiple biological indices of large benthic lO organisms in different evaluated river segments are obtained, then comparative analysis of various biological indices of large benthic organisms in different evaluated river segments is conducted, if number of biological indices showing a decreasing trend from lower reaches to upper reaches among all biological indices exceeds a preset threshold value, and all biological indices show a decreasing trend as time increases, it is 15 determined that there are ecological toxicity effects. In the present invention, multiple, long-term interval surveys and multi-dimensional, multi-index analysis methods are employed to accurately evaluate ecological toxicity effects of tailwater on receiving water bodies.