长春南湖水生生态系统中浮游动物群落特征

研究了2001～2002年长春南湖生态系统中的浮游动物群落特征． 发现浮游动物94种, 其中51种为轮虫． 浮游动物优势种存在明显的季节变化, 浮游动物的个体数量在夏季和秋季各出现一次高峰． 浮游动物年净产量为704.45 kJ·m^-2, 年总产量为1 642.50 kJ·m^-2; 全年浮游动物群落的P/B系数为41.4（以年净产量计）或96.4（以年总产量计）． 浮游动物群落对水柱原位浮游植物和浮游细菌的牧食力分别为2.57 kJ·m^-2·h^-1 和1.47 μg C·L^-1·h^-1, 是浮游植物和细菌同期净生产力的51.7%和32.9%．形成浮游动物净生产力的碳量是浮游植物总碳固定的8.2%． 浮游动物群落在一定程度上体现了南湖为温带富营养化湖泊的特征．

Characteristics of Zooplankton Community in the Aquatic Ecosystem of Nanhu Lake of Changchun

The zooplankton community characteristics were studied in the Nanhu Lake ecosystem of Changchun in 2001～2002. 94 Species of zooplankton were found, including 51 species of Rotifera. The seasonal changes of dominant zooplankton species were obvious. Twice peaks of zooplankton individual number were found in summer and autumn. The annual net and gross productions of zooplankton were 704.45 kJ·m^-2and 1 642.50 kJ·m^-2, respectively. The annual gross production of zooplankton was 13.9% of annual net production of phytoplankton. The P/B index of zooplankton community was 41.4（calculated by P_n）or 96.4（calculated by P_g）. Based on the determination result of in situ experiment, the grazing abilities of zooplankton community on phytoplankton and bacteriaplankton were 2.57 kJ·m^-2·h^-1 and 1.47 μg C·L^-1·h^-1 respectively,which were 51.7% of phytoplankton net productivity and 32.9% of bacteriaplankton net productivity in the same period. The carbon amount forming zooplankton net productivity was 8.2% of the total carbon amount fixed by phytoplankton. The zooplankton community indicates, to some extent, the feature of the Nanhu Lake as an eutrophicated lake in temperate zone.