淮北采煤塌陷区两个小型湖泊浮游甲壳动物群落结构及其与环境因子的关系

Community structure of crustacean zooplankton and its relationship with environmental factors in two small lakes of Huaibei excavating coal subsidence region

2017年4月、7月、10月和2018年1月对淮北采煤塌陷湖泊东湖和刘桥湖浮游甲壳动物群落结构的季节变化进行研究。结果表明:2个湖泊共记录浮游甲壳动物12种,其中枝角类7属8种,桡足类4属4种;东湖浮游甲壳动物的年平均密度和生物量(12.8 ind·L-1和0.26 mg·L^(-1))明显高于刘桥湖(4.4 ind·L-1和0.1 mg·L^(-1));东湖夏秋季的主要优势种为短尾秀体溞(Diaphanosoma brachyurum)和广布中剑水蚤(Mesocyclops leuckarti),冬春季为方形尖额溞(Alona quadranyularis)、盔形溞(Daphnia galeata)、卵形盘肠溞(Chydorus ovalis)和近邻剑水蚤(Cyclops vicinus);刘桥湖夏秋季的主要优势种为象鼻溞(Bosmina sp.)、短尾秀体溞和广布中剑水蚤,冬春季为方形尖额溞和近邻剑水蚤;东湖和刘桥湖Shannon多样性指数分别为0.64"0.27和0.93"0.29;冗余分析结果表明,水温、营养盐(TN、TP)和浮游植物生物量是影响2个湖泊浮游甲壳动物群落结构变化的重要因素;鲢、鳙鱼的捕食压力对浮游甲壳动物群落结构具有重要的影响。

The seasonal dynamics of community structure of crustacean zooplankton in the collapse lakes of Huaibei mining areas (Lake Donghu and Lake Liuqiao) were investigated in April, July, and October 2017 and January 2018. The results showed that a total of 12 species were recorded in two lakes, out of which 8 species (7 genera) belong to cladocera and 4 species (4 genera) belong to copepoda. The annual average density and biomass of crustacean zooplankton in Lake Donghu (12.8 ind·L^-1 and 0.26 mg·L^-1) were higher than those in Lake Liuqiao (4.4 ind·L^-1 and 0.1 mg·L^-1). In Lake Donghu, Mesocyclops leuckarti and Diaphanosoma brachyurum were the dominant species in summer and autumn, whereas Cyclops vicinus, Alona quadranyularis, Daphnia galeata, and Chydorus ovalis were the dominant species in winter and spring. In Lake Liuqiao, Bosmina sp., D. brachyurum and M. leuckarti were the dominant species in summer and autumn, whereas A. quadranyularis and C. vicinus were the dominant species in winter and spring. The average values of Shannon index in Lake Donghu and Lake Liuqiao were 0.64±0.27 and 0.93±0.29, respectively. Results from the redundancy analysis showed that water temperature, nutrient concentration (TN and TP), and phytoplankton biomass were main environmental factors affecting the community structure of crustacean zooplankton. The predation pressure of Hypophthalmichthys molitrix and Aristichthys nobilis had an important influence on the seasonal dynamics of crustacean zooplankton community in both lakes.