气候变暖间接地通过对顶级捕食者的影响简化了食物网
Eoin J O'Gorman1, Lei Zhao2, Rebecca L Kordas3
1School of Life Sciences, University of Essex, Colchester, UK. e.ogorman@essex.ac.uk.
Nature ecology & evolution
|October 5, 2023
概括
变暖放大了鱼类捕食者的对淡水生态系统的影响,改变了食物网和营养循环. 这些互动效应凸显了考虑变暖和物种相互作用对于预测生态影响的重要性.
科学领域:
- 生态生态学 生态生态学
- 环境科学 环境科学
- 水生生态系统 水生生态系统
背景情况:
- 全球变暖通过直接的生理效应和间接的生物相互作用对生态系统产生影响.
- 由于实验挑战,这些影响在自然环境中的相对重要性仍然不清楚.
- 淡水生态系统特别容易受到变暖和掠食者-猎物动态的改变的影响.
研究的目的:
- 研究气候变暖和鱼类捕食者对淡水生态系统结构和功能的相互作用影响.
- 为了确定温度如何影响自然流环境中的捕食者的级联效应.
- 评估变暖和掠食对食物网动态和营养循环的综合影响.
主要方法:
- 实地实验是沿着自然流的温度梯度进行的.
- 操纵性实验评估了变暖的影响和鱼类捕食者的存在.
- 测量包括藻类产量,微生物分解和食物网结构 (连接性,平均热量水平).
- 使用机械模型来理解观察到的变化的驱动因素.
主要成果:
- 顶级鱼类捕食者对藻类生长和微生物分解产生了级联影响,但仅在变暖条件下.
- 无论是变暖还是鱼类的存在,都没有改变食物网结构.
- 综合变暖和鱼类的存在导致了食物网连接率的下降和由于消费物种丧失的平均热量水平.
- 改变的物种相互作用被确定为温度诱导的热量级联的主要驱动因素.
结论:
- 气候变暖显著改变了顶峰捕食者对淡水生态系统的影响.
- 变暖和掠食的互动效应可以导致食物网结构和功能发生重大变化.
- 对变暖影响的生态预测应纳入生物相互作用和食物网动态,以避免低估.
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