EXPERIMENTAL STUDY ON THE EFFECT OF HABITAT ISOLATION ON RIVER ECOLOGY
Field investigations and an experiment were conducted in the Juma River, in the suburbs of Beijing, to study the effect of habitat fragmentation on river ecology using benthic macroinvertebrates as indicator species. Three experimental plots were isolated from a relatively undisturbed stream habitat with sheet iron. Benthic assemblages were measured by sampling periodically. The results indicate that the abundance, taxa richness and bio-diversity of invertebrates significantly decrease in the experimental plots owing to the habitat isolation. The smaller the experimental habitat plot, the more significantly these biotic indices decrease. Comparison of the benthic communities shows that the relative abundances of Ephemeroptera and Diptera are reduced significantly in the isolated plots, and that of Odonata and Lamellibranchia increase significantly. It is also found that the benthic communities need time to stabilize after isolation, and then present apparent variation with time. There is a relatively high degree of taxa turnover between isolated plots and the non-isolated reach, which can be attributed to the flight and dispersal of many aquatic insects in their adult stages. However, the benthic communities in isolated plots are not nested subsets of that in the natural non-isolated stream.
habitat isolation and fragmentation macroinvertebrates river ecology dispersal
Xuehua Duan Zhaoyin Wang
State Key Laboratory of Hydroseienee and Engineering, Tsinghua University,Beijing, China State Key Laboratory of Hydroseience and Engineering, Tsinghua University,Beijing, China
国际会议
第16届亚太地区国际水利学大会暨第3届水工水力学国际研讨会(16th IAHR-APD Congress and 3rd Symoposium of IAHR-ISHS)
南京
英文
2235-2240
2008-10-20（万方平台首次上网日期，不代表论文的发表时间）