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堤对河流生态系统的影响取决于大小,以及对拆除水的结果的影响
Rebecca L Brown1, Don Charles2, Richard J Horwitz2
1Department of Biology, Eastern Washington University, Cheney, Washington, USA.
概括
的大小对河流生态系统产生重大影响. 较大的水会导致更大的生态变化,这表明它们的移除为恢复河流和改善生态健康提供了最大的潜力.
科学领域:
- 河流生态学 河流生态学
- 环境科学环境科学
- 堤防影响研究研究
背景情况:
- 拆除水是河流恢复的一个关键战略.
- 大型水的生态影响得到了充分的记录,但小水的影响不太了解.
- 的大小是影响下游生态变化的关键因素.
研究的目的:
- 调查大大小如何影响下游的生态特征.
- 为了比较各种大小的水对生态的影响.
- 通过了解水特定影响,为河流恢复的优先确定提供信息.
主要方法:
- 在中大西洋地区对16座水进行了多学科研究.
- 测量生态变量,包括地形,水化学和水生/河岸生物群.
- 与下游-上游生态差异相关的水大小 (高度,液压停留时间).
主要成果:
- 较大的水对水面宽度等物理属性产生了更大的影响.
- 在较大的水下,水质更恶化 (溶解氧较低,温度更高).
- 的大小影响了营养动态和水生生物群落 (物种组成,多样性,污染耐受性).
- 植物的反应,包括入侵物种的存在,在大和小的影响之间有所不同.
结论:
- 的大小是生态影响的主要决定因素.
- 较大的水对河流生态系统的影响不成比例.
- 清除大的优先级应该考虑大的大小,以获得最大的恢复效益.
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