模仿自然流动制度的功能元素有助于在受监管的河流中促进本地鱼类的恢复
Ethan M Baruch1,2, Sarah M Yarnell1, Theodore E Grantham3
1Center for Watershed Sciences, University of California Davis, Davis, California, USA.
概括
在被堵塞的河流中恢复环境流动可以帮助本地鱼群恢复. 向自然流动模式的转变降低了本地鱼类减少的风险,并抑制了非本地物种.
科学领域:
- 生态生态学 生态生态学
- 水文学 水文学
- 保护生物学 保护生物学
背景情况:
- 改变的河流流程制度威胁到水生生态系统的健康和淡水生物多样性.
- 环境流恢复旨在通过支持生态功能和地形学过程来保护生物多样性.
- 由于监测缺陷和生态反应不确定性,环境流动的有效性往往不太清楚.
研究的目的:
- 分析环境流实施对加利福尼亚州一条被堵塞的河流中的鱼群的影响.
- 检查本地和非本地鱼群对年度流量制度的具体,可量化的变化所产生的反应.
- 评估功能环境流在支持本地鱼类恢复方面的有效性.
主要方法:
- 利用时间序列模型分析了25年的鱼群数据.
- 在实施环境流动之前和之后收集的数据.
- 检查了功能流组件的变化与鱼群准灭绝风险之间的关系.
主要成果:
- 功能性流动组件向其自然范围的转移降低了本地鱼群的准灭绝风险.
- 特定的流量组成部分 (干季持续时间,秋季脉冲,雨季时间) 将本地鱼类的准灭绝风险降低至少40%.
- 随着流量组成部分向自然范围转移,非本土物种的丰富性减少,而当它们转移时增加.
结论:
- 环境流动可以使本地鱼类受益,并抑制非本地物种,即使是对自然流动模式的适度转变.
- 这项研究提供了强有力的证据,证明了功能性环境流在规范河流恢复中的有效性.
- 恢复自然流动组件对于维持本地鱼群和整体水生生态系统健康至关重要.
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