Linking pattern and process in community assembly

包括竞争、捕食和扩散在内的生态过程在构建自然群落中起着重要的作用。然而，目前还不清楚这些过程如何促成物种组织、丰度和多样性的几种令人信服和解释不足的模式。我的研究计划的中心目标是解决我们对生态过程如何促成这些有趣的模式的理解上的差距。通过扩展我们对群落如何组成的知识，我的研究可以为保护和恢复行动提供信息，并帮助减轻入侵物种和气候变化的负面影响。我主要在陆地植物群落中进行这项研究。实验表明，大型植物物种是光的更好竞争者；然而，在竞争激烈的植被中，小型植物物种仍然很常见。我的目标是了解小物种如何在竞争的群落中生存下来，方法是：1)确定较小的植物物种是否通过在季节较早的时候生长和开花，在光照资源竞争较少的时候生存下来；2)测试草本植物群落中非短暂的小型植物物种表现出耐荫性的证据；以及3)检查当竞争更激烈时，大小优势是更明显，还是在土壤施肥后对植物的快速生长做出反应。为了理解在群落中组织物种的过程，我研究了为什么一些物种经常被发现在一起或分开(分别是积极的和消极的共生)，以及为什么共存的植物物种在一些基本特征上不同(例如，开花时间)。我的研究将通过以下两个方面增加我们对共生模式的理解：1)使用来自全球实验网络的数据来测试负共现物种对是否更有可能随着时间的推移而减少数量，以响应施肥；2)测试物种共生模式是否与土壤养分和竞争强度(田间估计)的变化有关。我的研究还将通过测试来调查为什么共存植物物种在开花时间上的重叠比预期的要少：1)当相邻植物物种的开花时间不重叠时，种子产量是否会提高；以及2)共存物种之间的开花时间重叠是否会受到经历的竞争强度的影响。我提出的研究计划将回答以下基本问题：小型植物物种如何避免被大型物种竞争、什么过程驱动物种共存的模式，以及什么因素导致共存植物物种之间观察到的开花时间不同步。这项研究解决了关于生态过程如何有助于植物群落中不完全了解的物种组织模式的具体和基本问题，解决了植物生态学领域的关键问题。

Ecological processes including competition, predation, and dispersal play important roles in structuring natural communities. However, it remains unclear how these processes contribute to several compelling and insufficiently explained patterns of species organization, abundance, and diversity. The central goal of my research program is to address gaps in our understanding of how ecological processes contribute to these intriguing patterns. By extending our knowledge of how communities are assembled, my research can inform conservation and restoration initiatives and help mitigate the negative impacts of invasive species and climate change. I conduct this research primarily in terrestrial plant communities. Experiments indicate that large plant species are better competitors for light; however, small species remain common in vegetation where competition is intense. My goal is to understand how small species to persist in competitive communities by 1) determining whether smaller plant species survive competition with taller species by growing and flowering earlier in the season, when light resources are less contested, 2) testing for evidence that small, non-ephemeral plant species in herbaceous communities exhibit shade tolerance, and 3) examining whether a size-advantage is more apparent when competition is more intense, or in response to rapid plant growth following soil fertilization. To understand the processes that organize species within communities, I examine why some species are regularly found together or apart (positive and negative co-occurrence, respectively), and why coexisting plant species differ in some fundamental characteristics (e.g. flowering time). My research will increase our understanding of co-occurrence patterns by 1) using data from a global network of experiments to test whether negatively co-occurring pairs of species are more likely to decrease in abundance over time in response to fertilization, and 2) testing whether species co-occurrence patterns are related to variation in soil nutrients and competition intensity (estimated in the field). My research will also investigate why coexisting plant species overlap in flowering time less than expected by testing: 1) whether seed production improves when neighbouring plant species do not overlap in flowering time, and 2) whether overlap in flowering time among coexisting species is influenced by the intensity of competition experienced. My proposed research program will answer fundamental questions concerning how small plant species avoid being outcompeted by larger species, what processes drive patterns of species co-occurrence, and what factors contribute to observed flowering time asynchrony among coexisting plant species. This research addresses specific and fundamental questions about how ecological processes contribute to incompletely understood patterns of species organization in plant communities, addressing key questions in the field of plant ecology.