三峡库区蓄水期长江口底栖生物数量动态分析  

Fluctuation in abundance of benthic organisms in the Changjiang Mouth during the reservoir time of the Three-Gorges Reservoir

作　　者：吴耀泉[1] 

机构地区：[1]中国科学院海洋研究所,山东青岛266071

出　　处：《海洋环境科学》2007年第2期138-141,共4页Marine Environmental Science

基　　金：国务院三峡工程建设委员会资助项目(SX2004-010)

摘　　要：三峡库区蓄水期于2004年在长江口区进行季节性（2、5、8、11月）综合调查。结果表明，该水域出现底栖生物种类依序为2月127种，5月为114种，8月和11月分别为83种和97种。在种类组成中，以多毛类占首位（42—70种）、其次软体类17—32种。甲壳类和棘皮类较少。底栖生物优势种有15种，其优势度（D2）值以多毛类丝异须虫（0．27-0．36）和小头虫（0．18—0．26）明显高于其他种类。底栖生物的平均总生物量以2月和5月较高，分别为19．7g／m^2和23．4g／m^2。在生物量组成中，以软体类最高为5．6—12．2g／m^2。底栖生物的平均总密度以5月和11月最高，分别为623．0个／m^2和781．7个／m^2。在生物密度组成中，多毛类的密度居首位（194．8—625．6个／m^2）。底栖生物多样性指数（H’）值最高为2月（2．94）和5月（2．76）。生物种类丰度指数（D）值以2月较高为1．34。各月的生物种类均匀度指数（J）值均不足1。通过调查分析，长江口外水域及口北少数站的底栖生物量和密度，仍保持高于河口附近测站的分布格局。Analysis of seasonal fluctuation of species number of benthic organisms based on monthly investigation carried out in February （winter） , May （spring）, August （summer） and September （autunm） shows that February and May registered a peak of 127 and 114 species respectively as against 83 and 97 species in August and November. Of 15 dominant benthic species, Heteromastus filiformis and Capitella capitata have high dominance indices （ D2 ） between 0.27 and 0.36 and between 0. 18 and 0.26 respectively which are obviously higher than those of the other dominant species. High average total benthic biomass of 19.7g/m^2 was registered in February and 23.4g/m^2 in May as against much lower biomass of 12.7 g/m^2 in August and 19.6 g/m^2 in November. High total densities of 623.0 ind./m^2 was registered in May and 781.7 ind./m^2 in November. Much lower densities of 375.0 ind./m^2 and 309.5 ind./m^2 were recorded in February and August respectively. The monthly community diversity index （H＇） ranges from a moderate level of 2.42 and 2.94. Margalef＇s index （D） between 0.98 - 1.34 and the Pielou index （J） of 〈 1 shows uneven distribution of the benthic community in the river mouth. Analysis of monthly investigation of benthic biomass shows that the Changjiang Mouth and a few sampling stations north of it still maintain a rather higher biomass than that of adjacent sampling areas.

关 键 词：三峡库区蓄水 底栖生物生态 长江口 

分 类 号：Q-9[生物学] X17[环境科学与工程—环境科学]