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在生态网络中功能性灭绝的高频率
Torbjörn Säterberg1, Stefan Sellman, Bo Ebenman
1Department of Physics, Chemistry and Biology, Division of Theoretical Biology, Linköping University, SE-58183 Linköping, Sweden.
Nature
|July 9, 2013
概括
在物种消失之前,它们可以在功能上灭绝,从而影响生态系统. 保护工作应专注于生态功能,而不仅仅是物种的持续存在,以防止灭绝级联.
科学领域:
- 生态生态学 生态生态学
- 保护生物学 保护生物学
- 网络理论 网络理论
背景情况:
- 人类活动增加了物种死亡率和减少了种群,冒着生态系统状态转移的风险.
- 功能性灭绝发生在一个物种的消失导致其他物种的灭绝时,即使它仍然存在.
- 功能性灭绝的频率和模式在很大程度上是未知的.
研究的目的:
- 探索生态网络中功能性灭绝的频率和模式.
- 通过分析推导出食物网中物种的临界丰度值.
- 了解物种死亡率对生态系统稳定的影响.
主要方法:
- 开发了一种新的建模方法来确定临界丰度值.
- 增加物种的死亡率,以确定生态网络中的灭绝点.
- 将模型应用于自然和理论食品网络数据集.
主要成果:
- 经历死亡率增加的物种往往不是第一个灭绝的物种.
- 最多80%的最初灭绝涉及不同的物种,这表明先前的功能性灭绝.
- 大型,顶级掠食者物种比较小的,较低的食水平物种更容易受到功能性灭绝的影响.
结论:
- 功能性灭绝是生态网络中一个重要的,被低估的现象.
- 保护战略必须考虑生态功能,以防止生态系统崩.
- 以社区为导向的方法至关重要,优先考虑物种的角色而不仅仅是生存.
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