Effects of Plant Diversity and Functional Characteristics on Species Invasions

植物多样性和功能特征对物种入侵的影响

• 批准号: 9974159
• 负责人: David Hooper
• 金额: $ 20万
• 依托单位: Western Washington University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2002-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9974159&HistoricalAwards=false
• 关键词: Effects; Plant; Diversity; Functional; Characteristics

9974159HooperEcologists have hypothesized for decades that more diverse communities are more difficult for species to invade because greater species richness should leave less available resources for a potential invader to exploit. This research seeks to address three fundamental questions (1) Does diversity influence invasibility of communities? (2) Do functional attributes of invaders related to resource acquisition influence the success of their invasion? (3) Is there a greater probability of invasion success when the invader differs from community members in functional attributes related to resource capture? The experimental design allows separation of effects due to differences in plant composition from effects due to differences in functional group richness. Unlike previous studies that have inferred answers to these questions by surveying communities which have already been invaded, this project will directly test the patterns of invasion into communities that differ in both composition and richness of plant functional groups. It will study the role of competition as a mechanism involved in invasion outcome. The research will use already-established experimental communities in California serpentine grassland. These experimental communities allow control of several factors, including disturbance regime, soil fertility, and community history, which confound attempts to study these questions in already invaded ecosystems. By directly seeding in species that are not already a part of those experimental communities, but that occur in the local area, it also will be possible to control for the rate of propagule arrival. This control is critical for determining what limits the success of an invasion once propagules have arrived. Overall, this set of experiments will provide a direct test of hypotheses concerning community invasibility and its underlying mechanisms.

9974159 Hooperecologists假设数十年来，种类更加难以入侵，因为较高的物种丰富度应留下更少的可用资源，以供潜在的入侵者利用。这项研究试图解决三个基本问题（1）多样性会影响社区的无敌性吗？ （2）与资源获取有关的入侵者的功能属性会影响其入侵的成功吗？ （3）当入侵者与与资源捕获有关的功能属性中的社区成员有所不同时，入侵成功的可能性更大？由于功能组丰富度的差异，实验设计允许由于植物成分的差异与效应的影响分离。与以前的研究通过调查已经入侵的社区来推断这些问题的答案不同，该项目将直接测试入侵对植物官能团体组成和丰富性不同的社区的模式。它将研究竞争作为参与入侵结果的机制的作用。该研究将在加利福尼亚蛇形草原上使用已经建立的实验社区。这些实验社区允许控制几个因素，包括干扰制度，土壤肥力和社区历史，这些因素混淆了在已经入侵的生态系统中研究这些问题的尝试。通过直接在这些实验社区的一部分中直接播种，但会发生在本地，也可以控制繁殖速度的速度。一旦繁殖到来，这种控制对于确定限制入侵的成功至关重要。总体而言，这组实验将直接检验有关社区无敌性及其潜在机制的假设。