SGER: Rehabilitation of Impounded Rivers: Effects of Removal of a Kennebec River Dam on Food Webs

99-09717 ThorpRehabilitation of Impounded Rivers：Effects of Removal of a肯纳贝克河大坝对食物网的影响拆除大坝对河流的环境影响的证据是罕见的，即使数十个美国水电大坝将需要重新许可或退役在未来三年。 1999年，缅因州肯纳贝克河上的爱德华兹大坝将被拆除，自1837年以来第一次将24公里的河流恢复到自由流动的状态。索普博士和他的同事，包括几名本科生，将在大坝拆除前和拆除后11个月在河流的3个地点对鱼类、底栖和水生无脊椎动物、水生植物和藻类进行采样。各种分析将有助于研究人员证明大坝拆除对生态系统代谢的影响，支持食物网的能量来源以及食物网的复杂性。由于保留或拆除大坝的环境基础并不像经济理由那样发达，这项研究将有助于填补我们对河流生态系统的理解中的一个重要知识空白。

99-09717ThorpRehabilitation of Impounded Rivers: Effects of Removal of a Kennebec River Dam on Food WebsEvidence of environmental consequences of dam removal on rivers is rare, even though dozens of U.S. hydropower dams will need to be relicensed or decommissioned in the next three years. In 1999, the Edwards dam on Maine's Kennebec River will be removed, restoring 24 km of the river to a free-flowing state for the first time since 1837. Dr. Thorp and colleagues, including several undergraduate students, will sample fish, benthic and planktonic invertebrates, aquatic plants, and algae at 3 sites in the river immediately before dam removal and 11 months after. A variety of analyses will help the investigators demonstrate effects of dam removal on ecosystem metabolism, the sources of energy supporting the food web, and the complexity of the food web. Because the environmental bases for retaining or removing a dam are not as well developed as the economic justifications, this study will help fill an important knowledge gap in our understanding of river ecosystems.