DISSERTATION RESEARCH: Synthesizing the Mass-ratio and Novel-trait Hypotheses to Explain Variability in the Impact of Plant Invasions on Coupled C and N Cycling

论文研究：综合质量比和新性状假设来解释植物入侵对碳氮耦合循环影响的变异性

• 批准号: 1406809
• 负责人: Justin Wright
• 金额: $ 2万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-15 至 2018-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1406809&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Synthesizing; Mass; ratio

Invasive plant species can have significant detrimental effects on ecosystem services that sustain ecosystem and human health. These impacts, however, are highly variable and hard to predict, raising difficulties for policy makers deciding how to allocate finite resources to address plant invasions. This project aims to understand factors that drive variability in the impact of one of the most widespread invasive plant species in the eastern US, Microstegium vimineum (Japanese stiltgrass) on carbon and nitrogen cycling. Specifically, the project will investigate the relative importance of two hypotheses that describe variation in invader impacts: first, that species have greater impacts where they are most abundant; and second, that species have greater impacts where they function most differently from the resident vegetation with respect to the ecosystem process of interest. Investigators will use a combination of observational studies and field manipulations to test these hypotheses, and a modeling approach to link drivers of variability in invader impacts to biogeochemical processes that control nutrient fluxes from plant litter across varying soil environments. The modeling approach will explore invader characteristics and abundances that limit or promote its impact on carbon and nitrogen cycling. By combining observational, experimental and modeling approaches, this research will provide a unique and powerful synthesis that will both inform the management of this species and address key questions of basic ecological interest.Determining the role that individual species play in controlling ecosystem processes is one of ecology?s grand challenges as global distribution of organisms shift due to human activity. This project addresses how individual invasive plant species can impact critical ecosystem processes that have a strong influence on global climate, soil fertility, ecosystem productivity, and ecosystem resilience. This research will produce novel information on how the impacts of non-native species invasions on ecosystem functions are mediated by the individual and interactive effects of coexisting species. Such information will improve general theory on consequences and mechanisms of non-native species invasions under different conditions, and will advance our ability to predict when and where biological invasions will have the greatest effects. This research will result in broader impacts in three key areas. First, the project will provide excellent experience and broad training for an undergraduate student each academic year of the project and will substantially improve a PhD student?s research. Second, the PIs will disseminate their research findings to land managers, other ecologists, and the general public through a web site, web blog, public presentations, and publications. Third, the project will provide important information for predicting where and under what conditions invasive species will have the greatest impacts. Specifically, the focal species, Microstegium, is one of the most common invasive plants in eastern deciduous forests where it has significant community and ecosystem impacts. Improving the ability of land managers to efficiently target invasive removal and restoration efforts will greatly enhance conservation and management efforts in the eastern U.S.

入侵植物物种会对维持生态系统和人类健康的生态系统服务产生重大不利影响。然而，这些影响是高度可变和难以预测的，这给决策者决定如何分配有限的资源来解决植物入侵问题带来了困难。该项目旨在了解美国东部最广泛的入侵植物物种之一，日本高脚草（Microstegium vimineum）对碳和氮循环影响的变化因素。具体来说，该项目将调查描述入侵者影响变化的两种假设的相对重要性：第一，物种最丰富的地方影响更大；其次，这些物种对生态系统的影响更大，因为它们的功能与当地植被最不同。研究人员将使用观察研究和实地操作相结合的方法来验证这些假设，并采用建模方法将入侵者影响的可变性驱动因素与控制不同土壤环境中植物凋落物的养分通量的生物地球化学过程联系起来。建模方法将探索限制或促进其对碳和氮循环影响的入侵者特征和丰度。通过结合观察、实验和建模方法，本研究将提供一个独特而有力的综合，既可以为该物种的管理提供信息，也可以解决基本生态利益的关键问题。确定单个物种在控制生态系统过程中所起的作用是生态学的一个问题。由于人类活动，生物的全球分布发生了变化，这是一个巨大的挑战。该项目研究入侵植物如何影响对全球气候、土壤肥力、生态系统生产力和生态系统恢复力有重大影响的关键生态系统过程。本研究将提供关于非本地物种入侵对生态系统功能的影响是如何通过共存物种的个体效应和相互作用来调节的新信息。这些信息将改善关于不同条件下非本地物种入侵后果和机制的一般理论，并将提高我们预测生物入侵何时何地将产生最大影响的能力。这项研究将在三个关键领域产生更广泛的影响。首先，该项目将为每个学年的本科生提供出色的经验和广泛的培训，并将大大提高博士生的水平。年代的研究。第二，通过网站、网络博客、公开演讲和出版物向土地管理者、其他生态学家和公众传播他们的研究成果。第三，该项目将为预测入侵物种在什么地方和什么条件下会产生最大影响提供重要信息。其中，焦点种微剑属（Microstegium）是东部落叶林中最常见的入侵植物之一，具有重要的群落和生态影响。提高土地管理者的能力，有效地针对入侵的清除和恢复工作，将大大加强美国东部的保护和管理工作