The Community Structure and Biodiversity of Macrozoobenthos in Daoguanhe Reservoir, Hubei Province

Abstract

1999年对湖北道观河水库大型底栖动物进行6次采样,共检出大型底栖动物17种,隶属4门16属.其中软体动物3种,环节动物5种,节肢动物8种,线形动物1种.密度和生物量分别为142ind/m²和0.99g/m².优势种类为大红德永摇蚊和霍甫水丝蚓.密度季节变化顺序为春季 >冬季 >秋季 >夏季;生物量季节变化为春季 >冬季 >夏季 >秋季.密度和生物量的水平分布为上游 >库湾 >中游 >下游.生物量与水深呈负相关关系;与水温、底泥TN、TP无显著相关关系.应用Goodnight-Whitley生物指数等对水质进行评价,结果显示该水库受到中等污染.提出在深水水库中不宜用Shannon-Wiener指数和Margalef指数等多样性指数评价水质.;In order to provide theoretic base for reasonable utilization of fisheries resource and to offer ecological strategy to the assessment and protection of aquatic environment, we studied the community structure and biodiversity of Daoguanhe Reservoir, Hubei Proince bimonthly in 1999.Macrozoobenthos were sampled from thirteen sites.Seven taxa of zoobenthos were identified.They belonged to 16 genera, 9 families, 4 phyla.Those were 3 species of mollusks, 5 species of oligochaetes, 8 species of aquatic insects and 1 of nematode.The density and biomass of the benthic animals were 142 ind/m² and 0.99 g/m², respectively.The dominant species were Tokunagayusurika akamusi and Limnorilus hoffmeisteri.The seasonal density variation order was spring > winter > autumn > summer;and biomass ranked as spring > winter > summer > autumn.The horizontal variation tendency of both density and biomass were the upper reaches > the reservoir bay > the middle reaches > the lower reaches.There was a significant negative relation between benthos biomass and water depths;but no pronounced relations between biomass and water temperature, sediment TN, TP or pH.Water quality of the reservoir was evaluated using Goodnight-Whitley index and other biological and biodiversity indices.The results demonstrated that the reservoir was polluted.We suggest Shannon-Wiener index and Margalef index are not fitted to the assessment of water quality in deep reservoirs.