为研究新疆伊犁河谷上游水库水环境质量状况,基于生物多样性指数、综合营养状态指数、冗余分析（RDA）等方法,于2019年6月（丰水期）、9月（平水期）和12月（枯水期）对恰甫其海水库浮游动物及水环境理化指标进行了调查分析。结果表明：（1） 恰甫其海共检出浮游动物37种,其中原生动物17种,轮虫10种,枝角类4种,桡足类6种;优势种主要包括侠盗虫属（Strobilidium sp.）、匣壳虫属（Centropyxis sp.）、王氏似铃壳虫（Tintinnopsis wangi）、疣毛轮属（Synchaeta sp.）、广布多肢轮虫（Polyarthra vulgaris）,共5种;浮游动物丰水期、平水期和枯水期丰度分别为580.40 ind·L^-1、152.68 ind·L^-1、137.01 ind·L^-1,生物量分别为0.550 mg·L^-1、0.018 mg·L^-1、0.007 mg·L^-1,丰度和生物量最大值均出现在丰水期。（2） 浮游动物多样性指数存在典型的时空分布特征,Shannon-Wiener指数（H′）和Margalef指数（D）在丰水期呈现由库尾向坝前增高的趋势,在平水期和枯水期以库中最高,H′和D均值分别为1.19和0.82。（3） RDA结果表明,水温（WT）、化学需氧量（COD_Mn）和营养盐浓度如总氮（TN）、总磷（TP）、硝酸盐氮（$NO_{3}^{-}-N$）、亚硝酸盐氮（$NO_{2}^{-}-N$）、氨态氮（$NO_{4}^{+}-N$）、正磷酸盐（$PO_{4}^{3-}-P$）等是影响浮游动物群落结构变化的主要环境因子。综合生物多样性指数和综合营养状态指数结果表明,恰甫其海水质处于贫-中营养状态,水环境质量状况良好,可以作为鱼类越冬场、产卵场和索饵场。

To study the community structure of zooplankton and aquatic environment at Qapchy Lake, Xinjiang, China, a survey was conducted in July (abundant water period), September (level water period), and December (dry water period) in 2019. Biodiversity indices and comprehensive trophic level index method were used to analyze the aquatic environment state during different months. The redundancy analysis method was used to analyze the relationship between the structures of the zooplankton community and environmental factors. The results showed that: (1) Thirty-seven species of zooplankton were detected, including 17 species of protozoa, 10 species of rotifer, 4 species of Cladocera, and 6 species of Copepods. The community structure of zooplankton was dominated by Strobilidium sp., Centropyxis sp., Tintinnopsis wangi, Synchaeta sp., Polyarthra vulgaris, and Centropyxis sp. The abundance of zooplankton was 580.40 ind·L ^-1 during the abundant water period, 152.68 ind·L^-1 during the level water period, and 137.01 ind·L^-1 during the dry warer period. Zooplankton biomass was 0.550 mg·L^-1, 0.018 mg·L^-1, and 0.007 mg·L^-1 during the abundant water period, level water period, and dry water period, respectively. The maximum values of zooplankton abundance and biomass values appeared in the abundant water period. (2) The spatial and temporal distribution of the diversity index differed in each water period. In the abundant water period, H \mathrm{\text{'}} and D values showed an increasing trend from reservoir head to the dam. Conversely, in the level water and dry water periods, H \mathrm{\text{'}} and D values of zooplankton in the middle position of the reservoir showed the lowest values. H \mathrm{\text{'}} and D mean values of zooplankton in Qapchy Lake of three water periods were 1.19 and 0.82. (3) As the results of redundancy analysis showed, water temperature, chemical oxygen demand, and nutrient salt (including the concentration of TN, TP, $NO_{3}^{-}-N$, $NO_{2}^{-}-N$, $NO_{4}^{+}-N$, $PO_{4}^{3-}-P$) were environmental factors influencing the change in zooplankton community. Water temperature was the main factor affecting the community structure of zooplankton in different water periods. Based on the results from the biodiversity and trophic state indices, the water environment of Qapchy Lake was oligotrophy or mild moderately eutrophication, meaning that the water environment in the reservoir of the upper Ili River was less disturbed by herding, cropping, and human activities. The relatively healthy water environment made a good habitat for freshwater fishes, which was suitable for them as wintering, swamping, and feeding ground.