新疆伊犁河不同生境大型底栖动物群落及其影响因素

于2014和2015年7月对新疆伊犁河支流喀什河和巩乃斯河共14个采样点的大型底栖无脊椎动物进行了调查研究, 比较分析了自然、受损、坝下和保护区4种生境的大型底栖动物群落结构特征。共采集大型底栖动物14435头, 属10目39科81属(种), 其中水生昆虫、软体动物、寡毛类分别占93.8%、2.5%和3.7%。对不同生境大型底栖动物群落结构特征进行了分析比较, 结果表明: 自然生境在物种数、优势物种数、EPT物种数、密度和物种多样性方面均高于其他3种生境, 而坝下生境均最低, 保护区生境底栖动物群落结构优于受损生境和坝下生境。冗余分析(RDA)结果共解释了物种数据累计方差的54.1%, 流速、电导率、水温和海拔是影响伊犁河底栖动物分布的主要因素(F=2.28—4.34, P<0.05)。

COMMUNITY STRUCTURE AND ENVIRONMENTAL DETERMINANTS OF MACROINVERTEBRATES IN ILI RIVER

To investigate the community structure of macroinvertebrates in the Ili River, fourteen sampling sites were selected representing four habitat types, i.e., natural habitat, damaged habitat, under-dam habitat and protected area in July 2014 and 2015. A total of 81 macroinvertebrate taxa were collected, belonging to 39 families and 10 orders, of which, 75 species (93.8％) were aquatic insects, and 2 species (2.5％) were mollusks, and 3 species (3.7％) were oligo-chaete. The natural habitat had higher density, species richness, EPT richness and biodiversity of macroinvertebrates than others, and the under-dam habitat displayed the lowest values. Results of Redundancy Analysis (RDA) explained 54.1％ of the cumulative variance of species data. Monte Carlo permutation tests for the first axis and overall canonical ordination were significant, indicating that distribution of macroinvertebrates were mainly regulated by flow rate, con-ductivity, water temperature and altitude (F=2.28—4.34, P<0.05).