杭州地区3种典型水体环境水生昆虫群落特征及环境影响因子分析

Community Characteristics and Environmental Impact Factors of Aquatic Insects in Three Typical Water Environments in Hangzhou Region

2015年夏季(7—9月)对杭州市3种典型水体——西溪湿地、虎山水库、农田水系(萧山区文伟村水稻田)共15个采样点进行了3次调查,分析各水体水生昆虫群落结构及其与环境因子之间的关系,并评价各水体的水质状况.所有采样点共记录水生昆虫1840只,隶属于6目65科,其中蜻蜓目、鞘翅目、半翅目和双翅目为四大优势类群.群落相似性分析结果表明夏季水质对农田水系、虎山水库和西溪湿地的水生昆虫群落结构产生了中等程度的影响.农田水系富营养化严重,随着富营养化程度提高,其群落多样性下降,且水体中摇蚊数量明显增加.综合理化指标和生物指数评价结果显示,西溪湿地和虎山水库处于中度污染状态,农田水系处于重中度污染状态.这些结果为研究水生昆虫在水生生态系统中的作用以及重金属对水生昆虫生长发育的影响,提供了基础数据和理论支持.

In the summer of 2015(July to September),three typical water bodies in Hangzhou,Xixi Wetland,Hushan Reservoir,farmland water system(Wenwei village paddy field in Xiaoshan District),were investigated for three times.The community structure of the aquatic insects in each water body and its relationships with environmental factors were analyzed,and the water quality of each water body was evaluated.1840 aquatic insects were recorded in all 15 sampling sites,belonging to 65 families of 6 orders,of which dragonflies,Coleoptera,Hemiptera and Diptera were four dominant groups.The results of community similarity analysis showed that the water quality in summer had a moderate impact on the community structure of the aquatic insects in farmland water system,Hushan Reservoir and Xixi Wetland.The eutrophication of farmland water system was serious.With the increase of eutrophication degree,the community diversity decreased,and the number of chironomid in water body increased obviously.The results of comprehensive physical and chemical indexes as well as biological indexes showed that Xixi Wetland and Hushan Reservoir were in the state of moderate pollution,and farmland water system was in the state of severe and moderate pollution.These results provided basic data and theoretical support for the study of the role of aquatic insects in the aquatic ecosystem and the impacts of heavy metals on the growth and development of aquatic insects.