Collaborative Research: Dispersal Limitation as a Primary Factor in Determining Ectomycorrhizal Community Structure

提案标题：合作研究：作为确定外生菌根群落结构的主要因素的扩散限制机构：加州大学伯克利分校摘要日期：12/04/07外生菌根真菌与温带森林树木(如松树、橡树、杨树和桦树)互惠共生。这些真菌为树木提供矿物质营养，以换取糖，树木需要它们来生长和生存。在森林火灾或伐木等严重干扰之后，树木需要重新建立与菌根真菌的关系才能生存。先前的工作表明，这些真菌在受到这种干扰后，会以有序的顺序或“演替”到达。提出了一个新的模型，通过菌根真菌在孢子扩散和竞争相互作用方面的差异来解释这种观察到的模式。该模型关于气生孢子传播的限制和树根密度对真菌竞争的影响的四个关键预测将通过田间采样和操纵性生长室实验相结合进行验证。这项工作的更广泛的影响是，它将帮助我们了解树建立所必需的基本生物过程，并将为一组重要的未被研究的生物体建立基本的生态学知识基础。研究生和本科生的培养将是这项研究的重要组成部分。此外，这项工作利用其在雷耶斯角国家海滨的位置，将其反馈给公园内的管理决策，并通过针对公共教育的外联努力。

Proposal Title: Collaborative Research: Dispersal Limitation as a Primary Factor in Determining Ectomycorrhizal Community Structure Institution: University of California-Berkeley Abstract Date: 12/04/07 Ectomycorrhizal fungi are obligate mutualists with temperate forest trees such as pines, oaks, aspens, and birch. These fungi provide mineral nutrients to the trees in exchange for sugars, and trees require them for growth and survival. Following severe disturbance such as forest fires or logging, trees need to reestablish their relationships with mycorrhizal fungi in order to survive. Prior work has shown that these fungi arrive in an ordered sequence, or "succession", after such disturbances. A new model is proposed to explain this observed pattern through differences in spore dispersal and competitive interactions among mycorrhizal fungi. Four key predictions of this model concerning limitations to aerial spore dispersal and effect of tree root density on fungal competition will be tested through a combination of field sampling and manipulative growth-chamber experiments. The broader impacts of this work are that it will help us understand an essential biotic process necessary for tree establishment, and will build a foundation of basic ecological knowledge for an important group of understudied organisms. Training of graduate and undergraduate students will be an important component of this research. In addition this work takes advantage of its location within Point Reyes National Seashore by feeding back into management decisions within the park and through outreach efforts directed towards public education.