滦河中游干流底栖动物种类及分布

Species and distribution of macrozoobenthos in the main stream of middle reaches of Luanhe River.

2007年10月对华北地区的重要河流——滦河干流中游段的底栖动物进行了调查。结果表明:河流底栖动物种类较为丰富,共采集到底栖动物37种,其中优势种有5种;底栖动物平均生物量为5.4g.m-2,平均密度为1128个.m-2;蜉蝣目有1种在各采样点均出现,说明滦河中游干流水质较好;下游段动物多度、生物量及生物多样性指数值都较小,上游段相应均较大,底栖生物分布与具体生境条件密切相关,下游段人为扰动使得生境质量较差,不利于底栖动物生存繁殖。

An investigation of macrozoobenthos was conducted in the main stream of middle reaches of Luanhe River, an important river in North China in October 2007. The macrozoobenthos in the stream was richer in species. A total of 37 species were collected, 5 species of which were dominant species. The mean biomass was 5.4 g · m^-2, and the mean density was 1128 ind · m^-2. Only one species of Ephemeroptera was found in all sampling sites, suggesting that the wa- ter quality of the stream was good. The abundance, biomass, and biodiversity index of the macrozoobenthos in lower reaches were lower than those in upper reaches. Macrozoobenthos distribution had a close relation to habitat condition. Lower reaches were intensively disturbed by human activities, whose habitat condition was worse in quality, being not beneficial to the survival and reproduction of macrozoobenthos.