MCA: Plant-soil feedbacks and population dynamics of two arid system shrubs with contrasting spatial distributions and life histories

植物-土壤相互作用代表了生态研究的一个新兴和有影响力的领域，它正在提高对物种内和物种间植物-植物相互作用的理解，并控制群落结构。 本研究中包含的补充专业知识提供了一种新的合作，将植物-土壤反馈与植物种群增长相结合。 这种整合促进了对环境依赖性种群调节的理解，并有望推动未来的生态研究。 这项研究的结果将在种群水平上提供对植物-微生物反馈的重要理解，并允许对这些反馈进行长期评估，由于美国西南部干旱发生和严重程度的持续变化，这一点越来越重要。 一个综合的外联部分将支持目前为改善生态学和环境生物学方面的多样性参与所作的努力。 通过从一个现有的项目中招募代表性不足的学生参与者，该项目研究了身份与生态教育之间的关系，目前的项目提供了一个独特的机会，通过尖端研究评估学生的实地经验，这些研究涉及文化对学生保留和教育学的影响。这一综合为两项研究工作增加了价值。该项目考察了两种常见植物物种和一个经过充分研究的干旱植物系统的土壤微生物群落之间的反馈。 这些反馈将在美国西南部的两个优势物种，豚草dumosa（A。Gray）Payne Asteraceae、白色bur-sage和Larrea tridentata（DC.）科维尔Zygophyllaceae，杂酚油灌木。 这项研究将在约书亚树国家公园的一个实地进行，在那里，已经在一个永久性的地图上收集了超过35年的空间明确的人口数据。 将对微生物呼吸、微生物多样性和微生物组成响应于1）植物种类、2）植物大小和3）植物密度进行观察和实验研究，结果将用于预测未来的种群增长。 研究人员将使用专门的种群模型来测量种群轨迹的差异，这些差异包括：1）排除微生物活性，2）包括微生物呼吸但不包括多样性或组成，3）包括微生物多样性和组成但不包括呼吸，以及4）包括微生物呼吸，组成和多样性。 通过将土壤微生物组对植物生长和存活的影响纳入其中，该项目提高了理解植物固定性和可变栖息地条件如何相互作用以控制种群和社区的空间结构和动态的能力。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Plant-soil interactions represent a burgeoning and impactful area of ecological inquiry that is improving understanding of plant-plant interactions within and between species, and controls on community structure. The complementary expertise included in this study offers a novel collaboration to integrate plant-soil feedbacks with plant population growth. This integration advances understanding of context-dependent population regulation and promises to advance future ecological research. Outcomes from this research will provide important understanding of plant-microbial feedbacks at the population level and permit long-term assessment of these feedbacks, which is increasingly important due to ongoing changes in the occurrence and severity of drought in the US Southwest. An integrated outreach component will support ongoing efforts to improve diverse participation in ecology and environmental biology. By recruiting underrepresented student participants from an existing project that examines the relationship between identity and ecology education, the current project provides a unique opportunity to assess student field experiences with cutting edge research that treats cultural influences on student retention, and pedagogy. This synthesis adds value to both research efforts.The project examines feedbacks between two common plant species and the soil microbial community of a well-studied arid plant system. These feedbacks will be studied at different life history stages of two dominant species in the US Southwest, Ambrosia dumosa (A. Gray) Payne Asteraceae, white bur-sage, and Larrea tridentata (DC.) Coville Zygophyllaceae, creosote bush. The study will occur in a field site at Joshua Tree National Park where more than 35 years of spatially-explicit demographic data have been collected within a permanently mapped plot. Observational and experimental studies of microbial respiration, microbial diversity, and microbial composition in response to 1) plant species, 2) plant size and 3) plant density will be conducted, and outcomes will be used to project future population growth. The researchers will use specialized population models to measure differences in population trajectories that differ by 1) exclusion of microbial activity, 2) inclusion of microbial respiration but not diversity or composition, 3) inclusion of microbial diversity and composition but not respiration, and 4) inclusion of microbial respiration, composition, and diversity. By including the influence of the soil microbiome on plant growth and survival, this project advances the ability to understand how plant immobility and variable habitat conditions interact to control the spatial structure and dynamics of populations and communities.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.