捕食者的多样性减弱了热带级流的作用
Deborah L Finke1, Robert F Denno
1Department of Entomology, University of Maryland, College Park, Maryland 20742, USA. dfinke@umd.edu
Nature
|May 28, 2004
概括
食物网中掠食者多样性的增加削弱了食物级联,减轻了自然敌人的对食草动物的影响,最终影响了植物生产力. 这凸显了更高的食物营养水平多样性如何改变生态系统的功能.
科学领域:
- 生态生态学 生态生态学
- 生态系统动力学 生态系统动力学
- 食物网络的相互作用
背景情况:
- 食物网的复杂性被假设为削弱陆地热带级流.
- 捕食者的多样性可以通过引入内捕食和共享猎物动态来增加食物网的复杂性.
- 理论表明,增加掠食者多样性可能会放松对食草动物的掠食,减轻对初级生产的级联影响.
研究的目的:
- 实证地研究掠食者多样性在自然陆地系统中调解初级生产力的作用.
- 为了比较简单与多样化的捕食者组合对食草动物和植物生产力的影响.
- 为了测试这种假设,增强的捕食者多样性削弱了食物源级流.
主要方法:
- 关节动物掠食者对食草动物和沿海沼泽地区植物生产力的影响的比较.
- 捕食者多样性的实验操纵,将一个简单的食物网 (单一的捕食者物种) 与一个复杂的食物网 (多样化的捕食者组合) 相比较.
主要成果:
- 增强的捕食者多样性被证明可以减轻自然敌人的对草食动物的影响.
- 捕食者多样性的增加导致了食物源级流的减弱.
- 变化在更高的食量层多样性显著改变了生态系统的功能.
结论:
- 捕食者多样性在介导陆地生态系统中热带级流的强度方面发挥着至关重要的作用.
- 多样化的捕食者组合所带来的复杂性可以显著改变生态系统功能,例如初级生产力.
- 这些发现强调了生物多样性在更高的食物层对生态系统稳定性和功能的重要性.
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