Dam would influence the flux of water and sediment, eventually disturbing ecological connectivity. In Asia, especially in China, there are many dams, but great scientific uncertainty still exists about their effects on downstream macroinvertebrates. Therefore, we investigated macroinvertebrate assemblages, in upstream and downstream reaches of a run-of-river dam on a tributary of the Xiangxi River, central China. Surber samples and associated physicochemical measurements were taken from five sites during the period from June 2003 to June 2007. According to the metrics selection principle of benthic biotic integrity index (B-IBI), we selected macroinvertebrate species richness and number of EPT taxa from 27 biological metrics to assess the effect of dam construction. We divided sites into three habitats (H1-H3) according to the impact extent of the dam. Using partial least squares (PLS), we developed two predictive models (macroinvertebrate species richness and number of EPT taxa) based on the environmental variables of the unregulated habitat (111). These models were then used to predict species richness and number of EPT taxa at impacted habitats (H2 and H3). To evaluate the impact of flow regulation residuals, i.e. the differences between observed and predicted values, were used to evaluate the impact of flow regulation. Significant impacts of flow regulation on macroinvertebrate species richness and number of EPT taxa were detected at impacted habitats (H2 and H3), where observed species richness were lower 8.7% and 28.1%, and EPT taxa also were lower 12.8% and 30.0%. Then, possible mechanisms for observed impacts were discussed. This study addressed the negative impacts of run-of-river dams on macroinvertebrates, which may lead to more sustainable management strategies.
英文摘要:
Dam would influence the flux of water and sediment, eventually disturbing ecological connectivity. In Asia, especially in China, there are many dams, but great scientific uncertainty still exists about their effects on downstream macroinvertebrates. Therefore, we investigated macroinvertebrate assemblages, in upstream and downstream reaches of a run-of-river dam on a tributary of the Xiangxi River, central China. Surber samples and associated physicochemical measurements were taken from five sites during the period from June 2003 to June 2007. According to the metrics selection principle of benthic biotic integrity index (B-IBI), we selected macroinvertebrate species richness and number of EPT taxa from 27 biological metrics to assess the effect of dam construction. We divided sites into three habitats (H1-H3) according to the impact extent of the dam. Using partial least squares (PLS), we developed two predictive models (macroinvertebrate species richness and number of EPT taxa) based on the environmental variables of the unregulated habitat (111). These models were then used to predict species richness and number of EPT taxa at impacted habitats (H2 and H3). To evaluate the impact of flow regulation residuals, i.e. the differences between observed and predicted values, were used to evaluate the impact of flow regulation. Significant impacts of flow regulation on macroinvertebrate species richness and number of EPT taxa were detected at impacted habitats (H2 and H3), where observed species richness were lower 8.7% and 28.1%, and EPT taxa also were lower 12.8% and 30.0%. Then, possible mechanisms for observed impacts were discussed. This study addressed the negative impacts of run-of-river dams on macroinvertebrates, which may lead to more sustainable management strategies.
关键词[WOS]:
BIOTIC INTEGRITY
; FISH ASSEMBLAGES
; DIATOM COMMUNITIES
; GORGES RESERVOIR
; RIVER SYSTEM
; INDEX
; FLOW
; DOWNSTREAM
; PATTERNS
; REMOVAL
1.Chinese Acad Sci, Inst Hydrobiol, State Key Lab Freshwater Ecol & Biotechnol, Wuhan 430072, Peoples R China 2.Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China
Recommended Citation:
Wang, Xingzhong; Cai, Qinghua; Jiang, Wanxiang; Qu, Xiaodong.ASSESSING IMPACTS OF A DAM CONSTRUCTION ON BENTHIC MACROINVERTEBRATE COMMUNITIES IN A MOUNTAIN STREAM,FRESENIUS ENVIRONMENTAL BULLETIN,2013,22(1):103-110
