DISSERTATION RESEARCH : Species pool influences on the structure and function of fungal symbiont communities

为了解释当地生态系统的多样性和物种组成，有必要说明更大区域的物种分布情况。在广泛的空间和时间尺度上发生的过程，如地理隔离和物种进化，驱动这些区域模式，并确定区域物种库，或可能占据一个位置的物种群。该项目将使用实验来确定当地社区或来自大区域的物种是否解释了与植物及其根部相关的真菌的数量和种类。由于这些真菌无处不在，它们是全球营养循环和生态系统生产力的重要驱动力。 将通过支持一名博士生的教育和培训以及代表性不足群体的本科生的参与，加强科学工作者队伍。 该项目将有助于改善园艺和保护，区域物种库将以多种方式影响当地社区的集会。 这个问题将被解决的真菌共生体与一个地方性的夏威夷植物，越橘的根。使用植物-真菌微宇宙，实验共生体物种池将被引入到无菌幼苗中，真菌物种的数量随着共生体最初被分离的地点的平均年龄和环境异质性而沿着变化。高通量分子方法将与物理测量和分析化学相结合，以评估实现本地共生体群落组成的根。将检验三个假设：（1）较老或环境异质性较大的区域将导致区域物种库中更大的功能多样性;（2）来自较老或环境异质性较大的区域的物种库将导致相对于区域物种库的规模而言更大的已实现的地方多样性;（3）区域物种库的丰富性和功能多样性将是共生功能的主要驱动力，以宿主植物的生物量和养分积累来衡量。一个区域的地质年代和环境异质性将通过区域物种库的组成与当地社区的聚集和功能联系起来。

In order to explain the diversity and species composition of local ecosystems it is necessary to account for species distributions across larger areas. Processes occurring over broad spatial and temporal scales, such as geographic isolation and species evolution, drive these regional patterns and determine the regional species pool, or group of species that could potentially occupy a location. This project will use experiments to determine whether local communities or species from large regional areas explain the number and kinds of fungi associated with plants and their roots. Because these fungi are ubiquitous, they are globally important drivers of nutrient cycling and ecosystem productivity. The scientific workforce will be strengthened through support for the education and training of a doctoral student and participation of undergraduates from underrepresented groups. The project will contribute to improved horticulture and conservation.The regional species pool will affect local community assembly in multiple ways. This problem will be addressed for fungal symbionts associated with the roots of an endemic Hawaiian plant, Vaccinium calycinum. Using plant-fungal microcosms, experimental symbiont species pools will be introduced to sterile seedlings, varying the number of fungal species along with the mean age and environmental heterogeneity of the sites from which the symbionts were initially isolated. High-throughput molecular methods will be used in combination with physical measurements and analytical chemistry to assess the realized local symbiont community composition within roots. Three hypotheses will be tested: (1) older or more environmentally heterogeneous regions will result in greater functional diversity in the regional species pool; (2) species pools from older or more environmentally heterogeneous regions will result in greater realized local diversity relative to the size of the regional species pool; (3) the richness and functional diversity of the regional species pool will be the primary driver of symbiotic function, measured as the host plant's biomass and nutrient accumulation. The geologic age and environmental heterogeneity of a region will be linked to local community assembly and function via the composition of the regional species pool.