【摘要】 河流连续性概念(rivercontinuumconcept,RCC)将自然河流生态系统视为物理和生物的连续体,河流物理环境的梯度变化决定了生物的演变格局.为探索自然河流系统受人类干扰后大型底栖无脊椎动物的演变规律,作者于2002年5月、8月、11月对安徽省祁门县阊江河1~6级支流的大型底栖无脊椎动物进行了调查,共获7纲57科101属119种,计8813头,并详细记载了各级支流样点的栖境特点.运用“河流连续性概念”理论分析结果表明该河1~6级支流大型底栖无脊椎动物各取食功能团演变趋势符合该理论,但上游至下游的生物区系演替程度明显小于未受干扰的自然河流,1~6级支流各功能团的分布(P/%)梯度变化趋于平缓,仅捕食者数量分布与理论预测模式比较接近.各级支流相同取食功能团的优势类群各异,其种类的耐污能力随河流级别的增加总体呈上升趋势.同级支流各取食功能团的分布(P/%)比例存在季节性差异.图2表3参15更多还原

【Abstract】 The river continuum concept (RCC) asserted that streams were continua of both geomorphologic and biological factors. The community structure of macroinvertebrates in river system was largely regulated by geomorphologic factors. The objective of this research was to explore longitudinal changes of functional feeding groups (FFGs) from first to sixth order tributaries of the Changjiang River continuum. The research was carried out in May, August and November of 2002, macroinvertebrates were sampled at 6 sites from first to sixth order tributaries, respectively, and the habitat characters of each site were recorded as well. As a result, 8 813 individuals of 119 species were totally collected, belonging 101 genera, 57 families and 7 classes. The data were analyzed and compared with RCC theory. Our study showed that the substrates and some other physical variables from 1st to 6th order tributaries of the Changjiang River presented a continuous gradient of physical conditions. Accordingly, the changing trend of each functional feeding group (P/%) from 1st to 6th order tributaries was congruent with RCC, however, the degrees of the gradient changes of shredder (P/%), collector (P/%) and scraper (P/%) groups were much smaller than those predicted by the theory. Furthermore, the distribution of functional feeding groups was seasonal. Dominant species of each functional feeding group from 1～6 order tributaries were analyzed and the pollution tolerance of the most dominant species was increasing gradually along the Changjiang River continuum. Fig 2, Tab 3, Ref 15更多还原