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      Dams and downstream aquatic biodiversity: Potential food web consequences of hydrologic and geomorphic change

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      Environmental Management

      Springer Science and Business Media LLC

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          Abstract

          / Responses of rivers and river ecosystems to dams are complex and varied, as they depend on local sediment supplies, geomorphic constraints, climate, dam structure and operation, and key attributes of the biota. Therefore, "one-size-fits-all" prescriptions cannot substitute for local knowledge in developing prescriptions for dam structure and operation to protect local biodiversity. One general principle is self-evident: that biodiversity is best protected in rivers where physical regimes are the most natural. A sufficiently natural regime of flow variation is particularly crucial for river biota and food webs. We review our research and that of others to illustrate the ecological importance of alternating periods of low and high flow, of periodic bed scour, and of floodplain inundation and dewatering. These fluctuations regulate both the life cycles of river biota and species interactions in the food webs that sustain them. Even if the focus of biodiversity conservation efforts is on a target species rather than whole ecosystems, a food web perspective is necessary, because populations of any species depend critically on how their resources, prey, and potential predators also respond to environmental change. In regulated rivers, managers must determine how the frequency, magnitude, and timing of hydrologic events interact to constrain or support species and food webs. Simple ecological modeling, tailored to local systems, may provide a framework and some insight into explaining ecosystem response to dams and should give direction to mitigation efforts.KEY WORDS: Dams; Food webs; Hydrologic disturbance; Predator-prey dynamics; Succession

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          Most cited references 49

          • Record: found
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          Diversity in tropical rain forests and coral reefs.

          The commonly observed high diversity of trees in tropical rain forests and corals on tropical reefs is a nonequilibrium state which, if not disturbed further, will progress toward a low-diversity equilibrium community. This may not happen if gradual changes in climate favor different species. If equilibrium is reached, a lesser degree of diversity may be sustained by niche diversification or by a compensatory mortality that favors inferior competitors. However, tropical forests and reefs are subject to severe disturbances often enough that equilibrium may never be attained.
            Bookmark
            • Record: found
            • Abstract: not found
            • Article: not found

            The Paradox of the Plankton

             G. Hutchinson (1961)
              Bookmark
              • Record: found
              • Abstract: not found
              • Article: not found

              Competition and Biodiversity in Spatially Structured Habitats

               David Tilman (1994)
                Bookmark

                Author and article information

                Journal
                Environmental Management
                Environmental Management
                Springer Science and Business Media LLC
                0364-152X
                1432-1009
                November 1996
                November 1996
                : 20
                : 6
                : 887-895
                Article
                10.1007/BF01205969
                8895411
                © 1996

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