Review of the Occurrence of Herbicides in Environmental Waters of Taihu Lake Basin and Its Potential Impact on Submerged Plants

Abstract

Over the past 20 years, a series of problems caused by eutrophication in Taihu Lake, and its surrounding environmental waters has received sustained and widespread attention. With the gradual extinction of submerged plants, which are the important basis for maintaining the aquatic ecological health of lakes, Taihu Lake has shifted from a grass-type clearwater lake to an algae-type turbid lake, posing severe challenges to the aquatic ecological health and security in this region. In addition, the occurrence of herbicides in the environmental waters of the Taihu Lake region has attracted the attention of several researchers. This study reviewed the evolution of submerged plants in Taihu Lake over recent decades. Moreover, the use of herbicides in the Taihu Lake region and their environmental occurrence in the past 20 years were statistically analyzed, and their toxic effects on submerged plants in previous reports summarized. Then, the potential impact of the environmental occurrence concentration of herbicides on submerged plants in the Taihu Lake region was evaluated. In conclusion, according to the results reported in the past paper, the environmental herbicide concentration in Taihu Lake has sometimes reached a level that can affect a variety of submerged plants, especially in the germination stage, which means that as an important cause of the degradation of submerged plants in shallow lakes, the effect of herbicides needs to be paid more attention to. The results of this review offer significant guidance for promoting science-based and standard use of herbicides and preventing their ecological risks in this region.