Control of Tree Invasion of Oldfields by Cryptic Keystone Species

9306330 Ostfeld树木入侵开阔地对森林再生、生物多样性的产生和野生动物栖息地的过程至关重要。先前的研究提供的证据表明，啮齿动物对树木种子和幼苗的消耗对森林发育过程中树木入侵的速率和物种组成有着深远的影响。现有的关于老田演替、关键种和植食性植物相互作用的理论不能为预测啮齿动物的影响提供基础，这些影响包括：（1）啮齿动物种群动态，（2）入侵地点的生境特征，（3）种子和幼苗的密度和组成，（4）幼苗的大小和生长速度，（5）距林缘的距离。这项研究将使用实验，比较和建模方法来预测小型哺乳动物对森林再生的影响。从现场观察和实验的结果将被用来作为参数的一个基于个人的预测模拟模型的树木入侵的动态在老领域。 这项研究的结果将提供有价值的信息，在美国东部的老田演替过程中的森林更新模式的影响机制。这些结果预计将适用于森林生物多样性的生态恢复，电力线走廊的维护和森林生态系统的管理。 ***

9306330 Ostfeld Tree invasion of open fields is critical to processes of forest regeneration, generation of biodiversity, and wildlife habitat. Previous research provided evidence that consumption of tree seeds and seedlings by rodents has a profound effect on the rate and species composition of tree invasion during forest development. Current theories concerning oldfield succession, keystone species , and herbivore-plant interactions are unable to provide a foundation for predicting effects of rodents given variation in: (1) rodent population dynamics, (2) habitat characteristics of invasion sites, (3) density and composition of seeds and seedlings, (4) size and growth rate of seedlings, and (5) distance from the forest edge. This research will use experimental, comparative, and modelling approaches to generate a predictive understanding of the effects of small mammals on forest regeneration. Results from field observations and experiments will be used as parameters for an individual-based predictive simulation model of the dynamics of tree invasion in old fields. %%% Results from this research will provide valuable information on the mechanisms affecting patterns of forest regeneration during oldfield succession in the eastern United States. These results are expected to apply to ecological restoration of forest biodiversity, maintenance of powerline corridors, and the management of forest ecosystems. ***