砷污染已成为世界上许多淡水水体重要的环境问题之一。目前对砷危害水生生物的认识主要来自短期毒理学实验和生物富集研究，为了科学评价砷对水生态系统的健康风险，亟需加强砷对淡水生态系统的影响研究。本项目以受到砷污染的云南阳宗海为研究水体，拟开展砷影响浮游动物群落的综合研究。首先对阳宗海进行逐月采样，系统了解浮游动物的群落结构和多样性，揭示当前砷污染背景下浮游动物群落的时空变化特征及影响因素；利用微宇宙实验，研究砷污染对阳宗海浮游动物群落的直接和间接作用，认识不同类群、关键种对砷的响应特征，并甄别直接和间接作用；开展中型实验，探讨砷污染和富营养化的相互作用如何影响浮游动物群落，最终揭示阳宗海在受到砷污染和富营养化过程中浮游动物群落演替的驱动机制。该研究将丰富砷污染对浮游动物群落影响的理论认识，有助于科学评价砷污染对阳宗海生态系统的健康风险，并为云南高原湖泊的环境保护和污染物治理提供科学依据。

Arsenic pollution is one of the important environmental issues in many freshwaters around the world. The adverse effects of arsenic on aquatic organisms have been largely investigated in short-term ecotoxicological experiments to date. In contrast, little is known about the effect of arsenic on ecosystem health and freshwater ecosystems. The present project will be conducted to comprehensively study the impact of arsenic on the zooplankton community in Yangzong Lake, where arsenic pollution is a major environmental problem. First, we plan to sample the lake monthly to study the zooplankton community, hence we aim to reveal the spatial-temporal change characteristics of the zooplankton community and explore the determinant factors under arsenic stress. Second, we plan to study the direct and indirect effects of arsenic on the zooplankton community typical of Yangzong Lake and its watershed via a microcosm experiment. Through this experiment, our goal is to understand how different functional groups and keystone species of zooplankton respond to arsenic stress, and disentangle the direct and indirect effects of arsenic on zooplankton. Finally, we will perform a mesocosm experiment to study the interactive effect of eutrophication and arsenic pollution on the zooplankton community. This will help us understand how eutrophication and arsenic pollution modulate the succession of zooplankton community in Yangzong Lake together. The present study will improve our understanding of the effect of arsenic pollution on zooplankton community, help to objectively evaluate the threat of arsenic pollution to ecosystem health in Yangzong Lake, and provide scientific evidence for protecting the environment and pollution control in Yunnan plateau lakes.