Dimensions US-China: Collaborative Research: Microbe eco-evolutionary feedbacks as drivers of plant coexistence and diversity gradients

草地占全球陆地面积的26%，占农业生产用地的80%。除了在农业上的重要性外，草原还在各种生态系统服务中发挥关键作用，包括生产清洁水和预防洪水。天然草原往往物种丰富，随着年降水量的增加而增加，随着干扰而减少。这些多样性模式可能会产生重要的后果，因为物种丰富的草原已被证明更有生产力，对干旱，洪水或龙卷风破坏等不可预测的事件更具弹性。了解植物多样性格局和植物多样性效益的控制过程，对更好地管理草原地区至关重要。在草原上共存的植物物种的丰富多样性的创造和维持的不同过程是未知的，但最近的研究表明，植物病原体可能发挥作用。该项目通过在美国和中国的多个实地进行平行实验，研究植物病害在多大程度上决定了草原植物多样性的自然模式。本科生，研究生和博士后研究人员将接受不同领域和实验室方法的培训，包括来自伊利诺伊州，密苏里州和堪萨斯研究地点附近的学院和社区学院的学生和教师。这一项目的数据将为牧场管理提供新的方向，并提高农业和当地生态系统的产量和复原力，预计病原体在植物系统发育多样性低、植物遗传多样性低和降水量高的草原上积累和限制植物生产力的作用最大。这些预测将通过一套协调的实地观察，实地操作，温室试验，在北美和亚洲草原上进行平行的多样性和降雨梯度进行测试。具体而言，植物和病原体系统发育多样性的模式，由于遗传多样性的植物抗性的模式，以及生态和进化反馈的模式将在美国中部和中国的降雨梯度进行测试。实验植物群落的降雨操作将测试植物物种共存的环境依赖性，植物多样性的生产力效益，以及病原体作为这些过程的驱动因素的作用。这些经验研究将与数学模型相结合，以预测植物生物多样性的格局和效益，并预测草原对环境扰动的脆弱性。

Grasslands comprise 26% of global land area and 80% of agriculturally productive land. In addition to their agricultural importance, grasslands also play key roles in diverse ecosystem services, including the production of clean water and the prevention of flooding. Native grasslands are often very species-rich, with richness increasing with increasing annual precipitation and declining following disturbance. These patterns of diversity can have important consequences because species-rich grasslands have been shown to be more productive and more resilient to unpredictable events like drought, flooding, or tornado damage. It is essential to understand the processes that govern both the patterns of plant diversity and the benefits of plant diversity to better manage grassland areas. The different processes that create and maintain the rich diversity of plant species coexisting in grasslands are unknown, but recent research suggests that plant pathogens may play a role. This project examines the extent plant disease determines natural patterns of plant diversity within grasslands by conducting parallel experiments at multiple field sites within the United States and China. Undergraduates, graduate students and post-doctoral researchers will be trained in diverse field and laboratory methods, including students and faculty from colleges and community colleges adjacent to study sites in Illinois, Missouri and Kansas. Data from this project will generate new directions for the management of rangelands and also lead to improvements in the yield and resilience of agricultural and native ecosystems.Pathogens are predicted to accumulate and limit plant productivity most strongly in grasslands with low plant phylogenetic diversity, low plant genetic diversity and high precipitation. These predictions will be tested through a coordinated set of field observations, field manipulations, and greenhouse assays, performed on parallel diversity and rainfall gradients in North American and Asian grasslands. Specifically, patterns of plant and pathogen phylogenetic diversity, patterns of plant resistance due to genetic diversity, and patterns of ecological and evolutionary feedback will be tested across rainfall gradients in central United States and China. Rainfall manipulations of experimental plant communities will test environmental dependence of plant species coexistence, productivity benefits of plant diversity, and the role of pathogens as drivers of these processes. These empirical studies will be integrated with mathematical models to generate predictions of patterns and benefits of plant biodiversity, as well as predictions of vulnerabilities of grasslands to environmental perturbations.