中文摘要：

生物多样性监测和保护过程中通常用到指示类群,然而对于这些指示类群有效性的测度仍然十分欠缺。为探讨不同类群水生昆虫群落的一致性及空间因子、环境变量的相对影响,作者于2010年4月对东苕溪流域源头溪流21个采样点进行了调查。共记录水生昆虫7目44科92属130种。我们将水生昆虫群落划分成鞘翅目（C）、蜉蝣目＋襀翅目＋毛翅目（EPT）和双翅目＋广翅目＋蜻蜓目（DMO）3个类群。一致性分析结果表明：3个类群的群落一致性（r）较高,分别为C对EPTr=0.65（P〈0.001）、C对DMOr=0.67（P〈0.001）、EPT对DMOr=0.82（P〈0.001）。方差分解表明环境变量是影响不同类群水生昆虫群落结构的主要因素,空间因子的影响相对较小。环境因子中影响不同类群水生昆虫群落的关键变量大体相似,其中海拔、pH、平均流速和化学需氧量是最主要的驱动因子。我们的结果表明该研究区域不同类群的水生昆虫群落一致性很高,且对环境变量的响应也相似;因此,在水生昆虫生物多样性保护中可考虑利用其中的某一类群,如蜉蝣目＋襀翅目＋毛翅目（EPT）类群,作为有效的指示类群。

英文摘要：

Indicator groups are often used for biodiversity monitoring and conservation, however, the effectiveness of these groups in representing biodiversity is rarely tested. To explore community congruence among different aquatic insect groups and how this may be affected by spatial factors and environmental variables, we carried out an investigation on aquatic insects in April 2010 in 21 headwater streams within the Dongtiaoxi Basin, China. In total, we recorded 130 species from 92 genera, 44 families and 7 orders. We divided the stream insects into three groups, Coleoptera （C）, Ephemeroptera ＋ Plecoptera ＋ Trichoptera （EPT）, and Diptera ＋ Megaloptera ＋ Odonata （DMO）. In Mantel tests, three aquatic insect groups showed significant cross-taxon concordance, C versus EPT （r = 0.65, P 0.001）, C versus DMO （r = 0.67, P 0.001） and EPT versus DMO （r = 0.82, P 0.001）. According to variance partitioning procedures, environmental variables were the major determinants of aquatic insect community structures, while spatial factors were less important. Species composition in different taxon groups exhibited similar relationships to environmental gradients. Altitude, pH, mean velocity and concentration of oxygen were the most important drivers of aquatic insect assemblage patterns. Overall, our results indicated that, at least in the studied region, community congruence among different aquatic insect groups was strong. We propose that one group, such as the EPT group, may be used as a biodiversity indicator in future cost-effective surveys.