【摘要】 <正> 一、前言水生昆虫是各类淡水水体中底栖大型无脊椎动物(简称底栖动物)的主要组成部分,一般情况下,水生昆虫无论在种类或数量方面均在各类底栖动物中居首位。水生昆虫不仅是多种经济鱼类特别是底层鱼类如鲤、鲫、青鱼等的天然优良饵料,而且在水体环境保护方面也起着重要的作用。部分水生昆虫能摄食水体底部沉积的有机物质,在加速水体内的物质循环、促进水体的自净方面起着积极的作用;在环境水质系统监测及评价中,还可根据水生昆虫的种群结构、数量分布及其变动情况等资料来确定水质污染状况。更多还原

【Abstract】 It was done to investigate benthic macroinver-tebrates and assess water quality of Tuo Jiang River for the period 1983—1984. Eight stations of collecting specimens were set up in Tuo Jiang River. Using the methods of collecting specimens with Square wood frame and man-made base, twenty-eight families in seven orders of aquatic insects were got. Resistance of different species of aquatic insects to pollution is different. Their community composition and abundance distribution have direct bearing on water quality pollution. The places with a lot of tipulidae larvae and chironomidae larvae, such as lower section in Ziyang, Shanyuan Ferry in Neijian and Lijia River Bend, are moderately polluted. The others slightly. In the different time of a year the level of water pollution is not the same. From September to November, the water pollution is slighter than that of the other time.更多还原