关键词：
大型底栖动物群落;优势类群;生产量;黑竹冲河
摘 要：
大型底栖动物在河流生态系统中发挥着重要作用,2003年6月至2004年6月间对汉江流域2级河流——黑竹冲河大型底栖动物群落优势种类的生产力进行为期一周年的调查研究,结果表明,主要优势种纹石蛾(Hydropsyche sp.)、扁蜉(Ecdyrus sp.)和细蜉(Caenissp.)生活史均为一年两代,河蚬(Corbicula fluminea)基本为三年一代。纹石蛾种群现存量在1月达到峰值,河蚬种群多度在3月、6—9月保持较高水平,生物量在10月达到峰值,而扁蜉种群的生物量和多度分别在4月和6月达到峰值,细蜉的生物量和多度则分别2月和6月达到峰值。采用龄期频率分布法(size-frequency method)测算的周年生产量(湿重或带壳湿重)和P/B系数分别为:纹石蛾,267.464g/m2.a,P/B为9.8;河蚬,783.1g/m2.a,P/B系数为2.3;扁蜉,267.46g/m2.a,P/B为15.4;细蜉,53.60g/m2.a,P/B为9.4。
译 名：
SECONDARY PRODUCTION OF SEVERAL DOMINANT MACROZOOBENTHOS IN HEIZHUCHONG STREAM OF HANJIANG RIVER BASIN
作 者：
YAN Yun-Jun and LI Xiao-Yu (School of Life and Technology, Huazhong University of Science and Technology, Wuhan 430074)
关键词：
Macrozoobenthos community;Dominant species; Production; Heizhuchong Stream
摘 要：
Macrozoobenthos community plays an important role in material cycle and energy flow in riverine ecosystem. During June, 2003 to June, 2004, an investigation on the life cycle and production of dominant species of macrozoobenthos community in a second-grade river of Hanjiang River Basin was carried out. From the upper reach to the lower reach of Heizhuchong Stream, we chose six types of habitats to sample. Station 1 (S1) lied in the middle of the stream with big round rocks there in the upper reach, station 2 (S2) was in the inner part of a weir with cobble substratum, station 3 (S3) in the middle of a peacefully flowing section with gravel-sand bottom, station 4 (S4) at the side of the riparian with aquatic macrophytes and snags, station 5 (S5) was in the middle of the riffle, station 6 (S6) at the lower reach with a sewage outlet ca 100 meters upper. At each station, two quantitative samples were taken with a 167μm D-frame kick net or a Surber net, and the samples were sieved with a 167μm net, sorted in a porcelain dish with naked eye. The specimens were kept in 10% formalin for later processing. The life cycle of the species were analyzed by the monthly size frequency distribution, the cohort and annual production were estimated by size frequency method. The results showed that the dominant species Hydropsyche sp.,Ecdyrus sp. and Caenis sp. each completed two generations a year, while Corbicula fluminea completed one generation per 3 years. Standing crop of Hydropsyche sp. reached its peak in January. Abundance of Corbicula fluminea kept at a higher level in March, June to September, and its biomass only attained its peak in October. Abundance and biomass of Ecdyrus sp. reached their peaks in April and June, respectively; while those of Caenis sp. peaked in February and June, respectively. The annual production and P/B ratio of the above dominant species estimated by size-frequency method were: Hydropsyche sp., 267.464g/m2.a wet wt and 9.8; Corbicula fluminea, 783.1g/m2.a wet wt with shell and 2.3; Ecdyrus sp., 267.46g/m2.a wet wt and 15.4; Caenis sp, 53.60g/m2.a wet wt and 9.4.
