实验证据表明,在热带森林的食物网中存在明显的竞争
Rebecca J Morris1, Owen T Lewis, H Charles J Godfray
1NERC Centre for Population Biology, Imperial College London, Silwood Park Campus, Ascot, Berkshire SL5 7PY, UK. r.j.morris@imperial.ac.uk
Nature
|March 19, 2004
概括
在热带森林中研究了明显的竞争,即物种通过共同的自然敌人相互作用. 移除采叶昆虫减少了寄生虫和增加了其他物种的种群,这表明它在构建多样化的昆虫群落中的重要性.
科学领域:
- 生态生态学 生态生态学
- 热带生物学 热带生物学
- 昆虫生态学 昆虫生态学
背景情况:
- 热带森林拥有非常多样化的食草昆虫群体,使得它们的结构和组织原理难以辨别.
- 虽然直接的物种间竞争受到宿主植物特异性的限制,但通过共同的自然敌人明显的竞争提供了一个替代的相互作用机制.
- 理论上讨论了明显的竞争,但缺乏经验证据,特别是在超多样化的热带生态系统中.
研究的目的:
- 实验性地研究明显竞争在热带昆虫群落结构中的作用.
- 为了确定特定的食草动物物种的移除是否会影响寄生虫率和其他与自然敌人共享的物种的种群密度.
主要方法:
- 从热带森林昆虫群体中试验移除两种食草动物物种 (二虫和虫叶矿者).
- 在处理和控制地点监测其他昆虫物种的寄生率和种群密度.
- 在带有和没有被移除的食草动物物种的地点之间比较生态参数.
主要成果:
- 在这两种移除病例中,与对照人群相比,在治疗地点观察到的寄生虫率明显较低.
- 在移除二虫的叶子矿工之后,一年后记录了相关昆虫物种的大量增加.
- 清除类动物也显示出增加丰度的趋势,尽管在统计学上并不显著.
结论:
- 这些发现为明显竞争在热带森林内昆虫群落结构中的重要作用提供了实证支持.
- 分享的自然敌人可以对人口动态和社区组成在极端多样化的热带生态系统施加相当大的影响.
- 这项研究强调了明显的竞争是塑造热带草食群体组织的关键过程.
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