【摘要】 2005年4月(春季)、7月(夏季)、10月(秋季)和2006年1月(冬季)。对长江口九段沙潮间带大型底栖动物进行了定性和定量调查。共采集到大型底栖动物73种,平均丰度442.94ind.m-2,生物量40.78 g.m-2。与历史资料比对,大型底栖动物的种数显著增加,新记录31种,曾经有过报道但未采集到标本的有3种;大型底栖动物的丰度变化不大,生物量有明显增加,多样性指数增大。大型底栖动物的丰度、生物量、多样性指数和相对重要性指数随季节的不同而有所变化,其中丰度和生物量以秋季最高,夏季次之,春季和冬季较低;多样性指数冬季最高,夏季次之,春季和秋季较低。优势种为谭氏泥蟹、梨形环棱螺、绯拟沼螺、琵琶拟沼螺、河蚬、焦河篮蛤、中国绿螂和丝异蚓虫;相对重要性指数值较高的有无齿相手蟹、天津厚蟹、谭氏泥蟹、中华拟蟹守螺、堇拟沼螺、绯拟沼螺、琵琶拟沼螺、梨形环棱螺、中国绿螂、焦河篮蛤、河蚬和丝异蚓虫。大型底栖动物的分布主要受水温、水文和工程的影响,此外,工程建设和互花米草扩散对其也造成了一定的影响。更多还原

【Abstract】 As a basal part,the macrobenthos is extremely important for wetland ecosystem.However the species diversity and distribution trend have not been fully investigated in the Jiuduansha wetland.In April(spring),July(summer),October(autumn) of 2005 and January of 2006(winter),9 sections were set for investigation of macrobenthic fauna in Jiuduansha wetland of the Yangtze River estuary.Along each transect,3 sites were sampled from the high to the low tidal zone.In this investigation,totally 73 species were collected,in which crustaceans were the richest in number of species.The species records in this investigation were more than those of previous data.31 species without previous record were acquired,while 3 species with previous record were not found in this investigation.The average diversity and biomass were 442.94 ind· m-2 and 40.78 g· m-2 respectively.The variety of average abundances was not even,the biomass was doubled and the diversity increased compared with the previous data.The abundance,biomass,diversity and index of relative importance(IRI) varied in different seasons.The abundance and biomass were the greatest in autumn,less in summer and the least in spring and winter;the diversity index was the highest in winter,lower in summer and the lowest in spring and winter.Along transects,the average values of abundance and biomass were the highest in the middle tidal muddy sand area,1306.73 ind· m-2 and 73.86 g· m-2 respectively.Among the dominant species were Ilyrplax deschampsi,Glauconome chinensis,Bellamya purificata,Assiminea violacea,A.latericea,A.lutea,Corbicula fluminea,Potamocorbula ustulata,Heteromastus filiformis.And 10 species with high IRI were: Ilyrplax deschampsi,Glaucomya chinensis,Helice tidentsinensis,Potamocorbula ustulata,Corbicula fluminea,Assiminea lutea,Bellamya purifcata,Heteromastus filiformis,Sesarma deihaani,Cerithidea sinensis took turns.The macrobenthos distribution was affected by temperature and other environmental factors(depth,salinity,tidal current velocity,sediment composition etc.).Additionally,constructional engineering and the expanding invasion of Spartina alterniflora interfered with the benthic community.更多还原