中文摘要：

新丰江水库是位于广东省境内的一座大型深水贫营养水库．为了解这一典型贫营养水体的浮游动物群落特征，于2002-2003年对该水库的轮虫和浮游甲壳动物进行了研究．新丰江水库的浮游动物主要为广布性种类，优势类群是桡足类，其幼体的数量高于成体，优势种为舌状叶镖水蚤、温中剑水蚤和微小近剑水蚤．枝角类优势种是长额象鼻涵、短尾秀体潘和角突网纹潘．轮虫优势种为个体较小的螺形龟甲轮虫和彩胃轮虫、优势种的个体体长为50—1450μm，个体最大的是舌状叶镖水蚤，平均体长为1190μm，个体最小的是彩胃轮虫，平均体长为80μm．在12月份，可能由于银鱼的摄食强度较高，导致大个体（主要为舌状叶镖水蚤及其大个体的哲水蚤幼体）的数量和生物量较低．在其余3个采样月份，浮游动物受银鱼影响相对较小，舌状叶镖水蚤的数量和生物量均远高于透明涵，可能与它们临界食物浓度及滤食方式的差异有关．根据对优势种的分析，新丰江水库的浮游动物群落具有典型的贫营养水体特点、

英文摘要：

Xinfengjiang Reservoir is a large deep oligotrophic reservoir located in Guangdong Province, South China. In order to understand the structure of zooplankton community in this oligotrophic water body, rotifers, cladocerans and copepods, were investigated in 2002 and 2003. The zooplankton species were mainly composed of eurythermal ones, and only a few thermophil ones were also found. The zoopkankton were dominated by copepods, in which nauplii and copepodites contributed more than 72.5% to the total abundance of copepods. The dominant species were Phyllodiaptomus tunguidus, Mesocyclops thermocyclopoides and Tropocyclops parvu. Cladocerans were mainly composed of Bosmina longirostris, Diaphanosoma brachyurum and Ceriodaphnia cornuta. Bosmina longirostris had the highest abundance in the cladocerans, and its dominance was probably related to its adaption to oligotrophic status and being free of invertebrate predation. Rotifer＇s dominant species were Keratella cochlearis and Chromogaster sp.. The body lengths of zooplankton in the reservoir ranged from 50 μm to 1400 μm. The largest dominant species was Phyllodlaptomus tunguidus with an average length of 1190 μm. Chromogaster sp. was the smallest dominant one, and its average length was 80 μm. In December, perhaps due to the heavy predation by ice-fish （Neosalanx taihuensis Chen）, the abundance and biomass of Phyllodiaptomus tunguidus were lower than in three other sampling periods. The dominance of Phyllodiaptomus tunguidus in the reservoir was probably related to its low threshold food concentration and efficient filtering mode in comparison with Daphnia hyalina. In viewpoint of the species composition, the zooplankton in Xinfengjiang Reservorir has a typical identification of oligotrophic water bodies.