DISSERTATION RESEARCH: Fungal endophytes and forest ecosystem function

所有的树叶表面和组织内都有不同的真菌群落。这组微生物惊人的多样性才刚刚开始被探索，对它们在生态系统中的作用还知之甚少。这个项目试图了解这些真菌的一个可能的作用：它们如何影响分解过程。一般的分解模式是，落叶落叶到达地面后，被土壤生物侵占并分解。如果生活在健康活叶中的一些真菌是潜在的分解者，那么与土壤生物相比，它们在分解垃圾方面将领先一步，而它们在树叶衰老时的存在甚至可能影响分解的进行。该项目将通过使用下一代高通量测序技术，结合生化和营养分析来验证这一假设，以识别单一、广泛分布的树种(多形绿僵菌)中的真菌，并通过操纵实验室和基于现场的实验在夏威夷的环境基质中通过分解过程来追踪这些真菌。这项研究的更广泛影响包括来自加利福尼亚州和夏威夷的高中生和本科生的参与。这项研究的结果对理解热带生态系统中的养分循环和微生物生物多样性具有重要意义，并将通过期刊文章、会议演讲以及与夏威夷的保护生物学家和土地管理人员的持续互动进行交流。

All leaves harbor diverse communities of fungi, both on their surface and within their tissues. The startling diversity of this group of microorganisms has just begun to be explored, and very little is yet known about their function in ecosystems. This project seeks to understand one possible role of these fungi: how they influence the process of decomposition. The general model of decomposition is that leaf litter is colonized and broken down by soil organisms after it reaches the ground. If some of the fungi inhabiting healthy, living leaves are latent decomposers, then they would have a head-start in breaking down litter compared to soil organisms, and their presence as the leaves senesce could even influence how decomposition proceeds. This project will test this hypothesis by using next-generation high throughput sequencing technologies, paired with biochemical and nutrient assays, to identify the fungi in a single, widely dispersed tree species (Metrosideros polymorpha), and trace these fungi through the process of decomposition in manipulative lab and field based experiments across an environmental matrix in Hawaii.The broader impacts of this study include the participation of high school students and undergraduates from both California and Hawaii. The results of this research have important implications for understanding nutrient cycling and microbial biodiversity in tropical ecosystems, and will be communicated through journal articles, conference presentations, and via ongoing interactions with conservation biologists and land managers in Hawaii.