Experimental Analysis of Species Percolation Through Communities

9207376群落中格伦物种的多样性部分是当地移民和灭绝动态的产物。移民障碍可能会导致主导地位的转移，并影响社区结构和功能。渗流理论为发展关于有机体在环境中运动的假说提供了一种机制。草原群落结构类似于渗流网络，但渗流网络的适用性尚未得到研究，而渗流理论对植物群落结构的适用性尚未得到评价。通过野外实验和模拟模拟验证了一系列假设，以确定渗流理论在预测草原植被优势度和多样性空间格局中的适用性。以前的研究表明，草原在小空间尺度上短期内具有高度的动态化。来自渗流网络中克隆生长刺激模型的初步结果表明，物种多样性受到移动障碍的影响。在超过临界阈值的情况下，物种多样性在这些模型中下降，因为优势竞争对手主导了可用的空间。将在草原植被中建立一系列试验性渗滤网络，并将监测多年生物种的克隆生长、局部迁徙和灭绝模式、物种多样性和空间格局。田间实验将通过模拟具有不同扩散速度和竞争能力的克隆植物的渗流来补充。这一研究将有助于确定渗流理论在草地植被小尺度植物群落动态研究中的应用。！！！F(Times New Roman符号&amp；Arial“h Y C抽象伊丽莎白·M·贝伦斯伊丽莎白·M·贝伦斯

9207376 Glenn Species diversity in a community is partially a product of the dynamics of local immigration and extinction. Barriers to immigration may result in shifts in dominance and affect community structure and function. Percolation theory provides a mechanism for developing hypotheses regarding movement of organisms through the environment. Community structure in grasslands resembles a percolation network, however, the applicability of percolation network, however, the applicability of percolation theory to plant community structure has not been evaluated. A series of hypotheses will be tested using field experiments and simulation modeling to determine the applicability of percolation theory to predicting spatial patterns of dominance and diversity in grassland vegetation. Previous studies have shown grasslands to be highly dynamic at small spatial scales over short periods. Preliminary results from stimulation models of clonal growth in percolation networks suggests that species diversity is affected by barriers to movement. Above a critical threshold, species diversity declined in these models as superior competitors dominated available space. A series of experimental percolation networks in grassland vegetation will be created and clonal growth of prennial species, local patterns of immigration and extinction, species diversity, and spatial pattern will be monitored. Field experiments will be supplemented by modelling percolation of clonal plants with different rates of spread and competitive abilities. This study will help to determine the utility of percolation theory to small-scale plant comm unity dynamics in grassland vegetation. ! ! ! F ( Times New Roman Symbol & Arial " h Y C abstract Elizabeth M. Behrens Elizabeth M. Behrens