地球地球行星的热量降级
James A Estes1, John Terborgh, Justin S Brashares
1Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA 95060, USA. jestes@ucsc.edu
Science (New York, N.Y.)
|July 19, 2011
概括
大型顶级消费者或顶级捕食者的丧失对全球生态系统产生了重大影响. 它们的消失会对生物多样性,疾病动态和生态系统功能 (如碳封存) 产生级联影响.
科学领域:
- 生态生态学 生态生态学
- 保护生物学 保护生物学
- 生态系统动力学 生态系统动力学
背景情况:
- 大型顶峰消费者曾经在全球范围内丰富,在生态系统结构中发挥着至关重要的作用.
- 人类活动导致了这些关键物种的广泛减少和丧失.
- 顶峰消费者损失的生态后果越来越多地被认为超越了伦理和美学方面的担忧.
研究的目的:
- 综合当前关于各种生态系统中顶峰消费者损失的级联影响的研究.
- 突出食量降级对生态过程的广泛而往往意想不到的影响.
- 强调需要跨学科的方法来理解和预测生态系统的反应.
主要方法:
- 审查经验研究,记录了顶峰消费者消失的生态影响.
- 关于自上而下的生态强迫的理论框架的综合.
- 分析受 trofhic cascades 影响的各种生态系统过程.
主要成果:
- 峰消费者损失在海洋,陆地和淡水环境中引发了显著的级联效应.
- 这些热带级流影响了关键的生态系统功能,包括疾病动态,野火制度和碳封存.
- 在全球范围内,对入侵物种和生物地化学循环的意外影响是明显的.
结论:
- 大型顶级消费者的消失代表了人类对大自然的普遍影响,并产生了深刻的生态后果.
- 热带降级破坏了生态系统的过程和弹性,需要紧急的科学关注.
- 跨学科研究对于预测顶峰消费者损失对全球生态系统的未来影响至关重要.
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