在黄河上游的布式水电开发下,水生食物网结构的演变
1State Key Laboratory of Regional Environment and Sustainability, School of Environment, Beijing Normal University, Beijing, 100875, China; School of Biological and Chemical Engineering, Guangxi University of Science and Technology, Liuzhou, Guangxi, 545006, China.
Journal of environmental management
|December 9, 2025
概括
水电大改变了河流生态系统,改变了鱼群和食物网. 虽然复杂性增加,但稳定性下降,揭示了受监管河流中的权衡.
科学领域:
- 生态生态学 生态生态学
- 环境科学 环境科学
- 渔业 科学 渔业 科学
背景情况:
- 布式水力发电开发显著改变了河流水文和息地.
- 这些变化会影响鱼群的聚集,食物网结构和生态系统的稳定性.
- 了解这些变化对于管理受监管的河流生态系统至关重要.
研究的目的:
- 调查黄河上游龙阳 ?? - 柳家 ?? 级联系统内鱼类食物网的时间变化.
- 量化食物网复杂性和稳定性在不同水力发电发展阶段的变化.
- 评估水电监管下的复杂性和稳定性之间的权衡,以及入侵物种的存在.
主要方法:
- 整合历史记录与当代现场调查进行时间分析.
- 开发了特定阶段的食物网模型来量化网络的复杂性 (物种丰富,链接数量,链接密度,连接性).
- 评估了食物网的稳定性,使用了诸如平均热量水平,杂食,模块化和准静止状态等指标.
主要成果:
- 布开发有利于居民物种和增加息地异质性,导致非本地物种入侵.
- 非本地物种重组了食用相互作用,增加了物种丰富性和拓复杂性.
- 尽管增加了复杂度指标 (链接,密度,热量级,食肉,模块化),但准静止状态下降,表明局部稳定性降低.
结论:
- 水力发电开发和入侵物种在河流生态系统中造成了复杂性-稳定性权衡.
- 密集的水力发电监管影响了生态系统的弹性.
- 需要综合管理策略来平衡工程影响,入侵物种控制和生态弹性.
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