Direct and Indirect Effects on Community Resilience in Oak Forests

[04:19640 . Ostfeld]生态学家的一个关键作用是预测相互作用的物种群落受到扰动的后果。了解群落结构和动态决定因素的传统方法侧重于种群对其他种群的直接影响，而忽略了间接影响。PI将开始在纽约州东南部的橡树林中测试直接和间接相互作用的重要性。具体来说，橡树的偶发性桅杆产生通过引起啮齿动物种群密度的短暂增加和鹿对空间利用的变化，刺激了一系列直接和间接的影响。反过来，啮齿动物似乎是低密度舞毒蛾种群的关键调节者，也是莱姆病病原的主要宿主。白尾鹿是成年鹿蜱的主要宿主，而成年鹿蜱是莱姆病的媒介。这个项目的目的是为了证明在橡树林中，最长的年份对啮齿动物种群动态的影响。这将通过大规模的田间试验进行测试，在2.25公顷的重复地块上添加或移除橡子。啮齿动物的数量将被监测一年。该奖项旨在证明大规模橡子操纵实验的可行性，并确定啮齿动物种群对操纵的反应是否如预测的那样。这些信息将为了解橡子生产对落叶森林景观的直接和间接影响提供第一步。

9419640 Ostfeld A critical role for ecologists is to predict the consequences of perturbations to communities of interacting species. Traditional approaches to understanding the determinants of community structure and dynamics have focused on direct effects of populations on other populations and have ignored indirect effects. The PI's will begin to test the importance of both direct and indirect interactions in oak forest of southeastern New York state. Specifically, episodic mast production by oak trees stimulates a series of direct and indirect effects by causing transient increases in the density of rodent populations, and changes in space use by deer. Rodents, in turn, appear to be key regulators of low-density gypsy moth populations, and are the primary reservoirs for the etiological agent of Lyme Disease. White-tailed deer are the primary host for adult deer ticks, the vectors of Lyme Disease. The purpose of this project will be to demonstrate the effects of mast years on rodent population dynamics in oak forests. This will be tested with a large scale field experiment in which acorns are added to or removed from replicated 2.25 ha plots. Rodent populations will be monitored for one year. %%% This is an award that is designed to demonstrate the feasibility of the large scale acorn manipulation experiment, and to determine if rodent populations respond to the manipulation as predicted. Such information will provide the first step in understanding the direct and indirect effects of acorn production in deciduous forest landscapes.