Plant-soil Feedback: A Mechanism to Explain the Spread of Invasive Species

植物-土壤反馈：解释入侵物种传播的机制

• 批准号: 0235052
• 负责人: Joan Ehrenfeld
• 金额: $ 59.19万
• 依托单位: Rutgers University New Brunswick
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-03-01 至 2007-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0235052&HistoricalAwards=false
• 关键词: Plant; soil; Feedback; Mechanism; Explain

ABSTRACT: Positive feedback has been proposed as a mechanism that results in thestable persistence of alternative states of an ecosystem. Such feedbackmay operate through plant-induced alterations in soil microbialcommunities, which in turn alter plant communities through changes innutrient dynamics. The recent replacement of native understory plantcommunities in eastern deciduous forests by apparently stable communitiesof exotic species provides an excellent model system in which to test thepresence of soil-mediated positive feedbacks. Previous studies of thissystem have shown that the recent shift in community composition is relatedto changes in both nutrient cycling processes and microbial communitycomposition. I propose greenhouse microcosm and field plot experiments totest whether plants drive changes in soil-based ecosystem processes byaltering the soil microbiota, and whether these changes in turn promote thedominance of the exotics. The proposed studies will explicitly contrast alitter-driven above-ground mechanism with a root-driven below-groundmechanism. BROADER IMPACTS: If the hypothesis of plant-soil positive feedback created byaltered nutrient cycling is supported, it would both demonstrate aplausible mechanism for the persistence of alternative stable communitiesand help explain the establishment of dominance by some exotic plantspecies. In addition, this project will train at least 1 graduate student and 3 undergraduates.

摘要：已提出积极的反馈作为一种机制，导致生态系统的替代状态持久性。 这种反馈婚姻是通过植物诱导的土壤微生物社区改变的，这反过来又通过改变创新动力学改变了植物群落。 最近，在东部落叶林中，近期稳定的外来物种群落在东部落叶林中取代了本地植物社区，这提供了一种出色的模型系统，可以在其中测试土壤介导的阳性反馈的呈现。先前对该系统的研究表明，社区组成的最新变化与营养循环过程和微生物社区结构的变化有关。 我提出了温室缩影和田间图实验，无论植物是否驱动基于土壤的生态系统过程的变化来促进土壤微生物群的变化，以及这些变化是否又促进了exotics的影响。 拟议的研究将与根驱动的地下机械机制明确对比易位驱动的地上机制。 更广泛的影响：如果支持植物土壤阳性反馈的假设，从而支持了替代营养循环，则两者都证明了持久性替代性稳定社区的合理机制，并有助于解释某些外来植物植物的统治地位。 此外，该项目将培训至少1名研究生和3名本科生。