Complexity and Stability of an Old-field Ecosystem: The Role of Asymmetrical Interaction Strengths and Food Web Toplology

老生态系统的复杂性和稳定性：不对称相互作用强度和食物网拓扑的作用

• 批准号: 0816504
• 负责人: Oswald Schmitz
• 金额: $ 47.33万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0816504&HistoricalAwards=false
• 关键词: Complexity; Stability; Old; field; Ecosystem

Biodiversity provides important environmental services that support human health and economic well-being. One important and as yet unanswered question is: How do species fit together to provide the most stable supply of those services? This question will be answered by experimentation with species of insect predators and herbivores, and grassland plants. The study will test new theory that the most stable supply of services comes from complex systems in which many weakly interacting species counterbalance the effects of a few strongly interacting species. The four-year field project will test this theory by assembling experimental food webs containing different mixtures of strongly and weakly interacting predator and herbivore species. The study will measure how well the different species mixtures sustain important life-support services such as plant production for forage and the nitrogen cycle. Human activities are fundamentally changing ecological systems with attendant loss of biodiversity. This study will test the resilience of ecological systems by quantifying the risks to ecological function of species loss. It will show how seemingly benign, weakly interacting species can, in combination with many other weakly interacting species, end up being the important threads that hold ecosystems together. The results will help guide conservation strategies that ensure long-term sustainability of vital environmental services. The project will also train the next generation of undergraduate and graduate students in methods for experimental analysis of natural ecosystem function in ways that enable them to make productive, direct contributions to environmental policy.

生物多样性提供重要的环境服务，支持人类健康和经济福祉。 一个重要但尚未得到解答的问题是：物种如何组合在一起，以提供这些服务的最稳定供应？ 这个问题将通过对昆虫捕食者和食草动物以及草原植物的实验来回答。 这项研究将测试一种新的理论，即最稳定的服务供应来自复杂的系统，在这种系统中，许多弱相互作用的物种抵消了少数强相互作用物种的影响。 这个为期四年的实地项目将通过组装实验性食物网来验证这一理论，这些食物网包含了强相互作用和弱相互作用的捕食者和食草动物物种的不同混合物。 这项研究将衡量不同物种混合物维持重要生命支持服务的能力，如饲料植物生产和氮循环。 人类活动正在从根本上改变生态系统，随之而来的是生物多样性的丧失。这项研究将通过量化物种损失对生态功能的风险来测试生态系统的复原力。它将展示看似良性的弱相互作用物种如何与许多其他弱相互作用物种结合，最终成为将生态系统连接在一起的重要线索。 研究结果将有助于指导保护战略，确保重要环境服务的长期可持续性。 该项目还将对下一代本科生和研究生进行自然生态系统功能实验分析方法方面的培训，使他们能够对环境政策作出富有成效的直接贡献。