长江口北支水域潮间带大型底栖动物研究

Study on intertidal macrobenthos in North Branch of Changjiang Estuary

2003年7月（丰水期）和2004年1月（枯水期）在长江口崇明北沿滩涂潮间带，共设置3个断面，按《全国海岸带和海涂资源综合调查简明规程》进行底栖动物调查。结果表明，丰水期底栖无脊椎动物17种，种类组成以甲壳动物最高（占41．18％），枯水期7种，种类组成以多毛类最高（占57．14％）；丰水期的优势种（优势度≥0．02）为伍氏厚蟹（Helice japonica）、豆形短眼蟹（Xenophthalmus pinnotheroides）、弹涂鱼（Perlophthalmus cantonensis）和无齿相手蟹（Sesarma hacmatocheir）。枯水期的优势种为豆形短眼蟹、小头虫（Capitella capitata）、日本刺沙蚕（Neanthss japonica）和纽虫（Nemertini spp.）。丰水期的生物量为枯水期的20．65倍；枯水期生物量下降的主要原因是无齿相手蟹、伍氏厚蟹、弹涂鱼的生物量出现大幅度下降，生物量、栖息密度和物种多样性指数呈现随离口门距离减小而呈增加的趋势，丰、枯水期底栖动物均分为3个群落。丰、枯水期群落演替现象明显。

In July of 2003（high water period） and Jan. of 2004（low water period） , three intertidal transets, which are Yongiongsha（A） section, Fuminlongchang（B） section and Dongwangsha（C） section, were set up in the north edge of Island Chongming. In high water period, there are 17 species and the species of crustacea are the most. In low waterperlod, the species of poiychaetous annelids are the most in sevea species. In high water period, Heliee japonica is the dominant species, on the other hand, in low water period, Xenophthalmus pinnotheroides is the main. As the biomass reduction of Sesar haematocheir,Heliee japonica and Periophthalmus eantonensis in low water period, the biemass in high water period is 20 - 65 times to the bionmss in low. Biomass, species number and species diversity are increased as the reduction of the distance to Chanjiang Estuary. The community sueceseion hetween the high and low water period was distinet.