Perturbation and Recovery of an Old-field Food Web

古老食物网的扰动与恢复

• 批准号: 0107780
• 负责人: Oswald Schmitz
• 金额: $ 21.28万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-01 至 2005-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0107780&HistoricalAwards=false
• 关键词: Perturbation; Recovery; Old; field; Food

A central goal in ecology is to develop a set of sound scientific principles that help to explain the effects of natural or human-induced disturbances on biodiversity and the functioning of natural ecosystems. This endeavor is motivated from a desire to: (1) forecast the fate of ecosystems, and the biodiversity contained within them, especially when native species are lost or exotic species invade as a consequence of the disturbances, and (2) restore the natural function of those systems through sound management. The proposed research aims to help develop the scientific principles needed to conduct sound environmental management by studying how top-predator species in New England meadow ecosystems control the diversity of plant species within those meadows and how disturbances alter that control. Past research on this system has revealed that, within a summer season, top predators such as spiders are important because they control the amount of damage that leaf-chewing herbivores such as grasshoppers and beetles inflict on plant species. It is unknown how environmental disturbances alter the ability of top-predators to control the herbivore damage. The proposed research will cause disturbances to the ecosystem by experimentally excluding spider predators from 2 m x 2m field plots for periods of 1 to 4 years. Subsequently, we will monitor how plant damage by herbivores and plant species composition of the field plots change as a consequence of short- and long-term predator exclusion. As part of this experiment, we will also reintroduce spider predators to plots after they have been excluded for 1 to 3 years. The aim is to determine whether the system can be restored to its original plant species composition and functioning following fixed periods of disturbance. Currently, ecologists believe that altering the presence of top predators in natural ecosystems should have lasting consequences for ecosystem function. Few studies, however, have evaluated the long-term responses of ecosystems when top-predators are removed and later reintroduced. The proposed work will offer key insight into the long-term consequences of disturbing the natural integrity of ecosystems on ecosystem function.

生态学的一个中心目标是制定一套合理的科学原则，帮助解释自然或人为干扰对生物多样性和自然生态系统功能的影响。这一努力的动机是希望：(1)预测生态系统及其所包含的生物多样性的命运，特别是当本土物种因干扰而丧失或外来物种入侵时，以及(2)通过健全的管理恢复这些系统的自然功能。这项拟议的研究旨在通过研究新英格兰草甸生态系统中的顶级捕食者物种如何控制这些草甸中植物物种的多样性，以及干扰如何改变这种控制，来帮助制定进行健全的环境管理所需的科学原则。过去对这一系统的研究表明，在夏季，蜘蛛等顶级捕食者是重要的，因为它们控制着蝗虫和甲虫等咀嚼树叶的草食动物对植物物种造成的损害。目前尚不清楚环境干扰如何改变顶级捕食者控制草食动物损害的能力。这项拟议的研究将通过实验将蜘蛛捕食者排除在2m x 2m的田地之外，为期1至4年，从而对生态系统造成干扰。随后，我们将监测草食动物对植物的破坏和田间地块的植物物种组成如何因短期和长期捕食者的排斥而发生变化。作为实验的一部分，我们还将在蜘蛛捕食者被排除1到3年后重新将它们引入地块。其目的是确定在固定的扰动期之后，该系统是否能恢复到原来的植物种类组成和功能。目前，生态学家认为，改变自然生态系统中顶级捕食者的存在应该会对生态系统功能产生持久的影响。然而，很少有研究评估顶级捕食者被移走并随后重新引入时生态系统的长期反应。拟议的工作将提供对扰乱生态系统自然完整性对生态系统功能的长期后果的关键洞察。