生命在边缘:两种不同的极端事件通过修改自上而下的控制来改变食物网
Delbert L Smee1,2, Benjamin A Belgrad1, Evan L Pettis3
1Dauphin Island Sea Lab, Dauphin Island, Alabama, USA.
Ecology
|June 18, 2025
概括
风和结等极端天气事件对墨西哥湾的食物网产生不同的影响. 最重要的捕食者变化揭示了生态系统如何应对气候变化和干扰.
科学领域:
- 生态生态学 生态生态学
- 气候变化生物学 气候变化生物学
- 海洋生物学 海洋生物学
背景情况:
- 气候变化加剧了极端天气事件,改变了生态系统和物种相互作用.
- 了解干扰对食物网的影响对于生态系统弹性至关重要,但仍未得到充分研究.
- 关于生态系统对极端事件的反应的长期数据很少见,特别是在河口系统.
研究的目的:
- 调查两个不同的干扰对墨西哥湾河口食物网的对比影响.
- 评估顶级捕食者丰富度的变化如何影响较低的热量级和社区结构.
- 确定上下势力在极端事件期间维持生态系统弹性方面的作用.
主要方法:
- 在墨西哥湾进行了一项为期8年的研究,监测了河口食物网的动态.
- 数据收集捕获了生态系统对风哈维 (2017) 和冬季风暴乌里 (2021) 的反应.
- 分析的重点是捕食者的丰富性,热带水平的变化和礁社区结构.
主要成果:
- 哈维风导致了由于渔业减少而增加的运动鱼和减少的猎物种群.
- 乌里冬季风暴导致运动鱼的数量大幅下降,中等热带水位急剧上升.
- 运动鱼的丰富性直接影响了中等掠食者种群,改变了礁社区结构.
结论:
- 极端事件塑造了河口社区,其影响是由顶级捕食者反应介导的.
- 运动鱼的自上而下的控制对于河口的弹性至关重要,通过干扰持续存在.
- 有效的休渔业管理对于在极端气候事件期间保持生态系统弹性至关重要.
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