东昌湖小型底栖生物群落结构研究

Studies on the Meiofauna Community in Dongchang Lake of Liaocheng

于2007年8月(夏季)和10月(秋季)分别在聊城市东昌湖取样进行了小型底栖生物的调查研究.结果表明,夏季、秋季小型底栖生物的平均丰度分别为1557±579ind.10cm-2和1182±530ind.10cm-2;平均生物量分别为1461±875μgdwt.10cm-2和735±432μgdwt.10cm-2.共鉴定出7个小型底栖生物类群,按丰度自由生活线虫为最优势类群,夏秋季节的优势度分别为82.4和91.7;其他类群夏季依次为寡毛类、腹毛类和涡虫类;秋季依次为腹毛类、桡足类、轮虫类、寡毛类;小型底栖生物分布在0～2cm的表层沉积物的比例在夏秋季节分别为42.5和68.0,线虫分布在0～2cm的比例分别为37.1和67.9.与冬春季节的研究结果(丰度为773±92ind.10cm-2和655±123ind.10cm-2;生物量为374±6μgdwt.10cm-2和307±54μgdwt.10cm-2;线虫的优势度为96.3和97.1)进行了比较,结果表明小型底栖生物的平均丰度和生物量均按夏季、秋季、冬季、春季呈递减趋势.

Two seasons investigation on the meiofauna in Liaocheng Dongchang Lake 3-point was made in August 2007 and October 2007. Results showed that the average abundance of meiofauna was 1 557±579 ind .10 cm^-2and 182±530 ind · 10 cm^-2and the biomass was 954.38±403.93 ug dwt · 10 cm^-2and 1 120. 72±487.21ug dwt · 10 cm^-2. A total of seven meiobenthic groups were identified. Free-living nematodes was the most dominant group in abundance with a relative dominance of 82.4 % in August and 91.7 % in October,followed by Oligochaeta,Gastrotricha and Turbellaria in summer and Gastrotricha, benthic harpacticoids copepoda, Rotifera and Oligochaeta in autumn. 42. 5 % of the meiobenthos distributed in the top 0-2 cm of sediment in summer,while nematode was 37. 1%. In autumn the number was 68.0 % and 67.9 %. After the investigation of summer and autumn,the study made a comparison to the results of December 2006 and April 2007. （the results were 773±92 ind · 10 cm 2and 655 ±123 ind · 10 cm^-2in abundance; 374±6 ug dwt · 10 cm^-2and 307±54 ug dwt · 10 cm^-2 in biomass; the dominant group-nematodes with a relative abundance 96.3 % in winter and 97.1% in spring）. The results showed that the average abundance of meiofauna was decreasing from summer, autumn,winter to spring. The biomass showed the same trend.