Quantification of Organic Nitrogen use in FACE and Culture Experiments

大部分植物的氮供应，特别是树木，是通过共生（菌根）真菌，从他们的宿主树木获得糖和作为回报转移氮。然而，方法上的困难限制了菌根真菌在满足植物氮需求方面的作用的量化。在这个项目中，碳和氮同位素的比例从两个田间实验在杜克大学和莱因兰德，威斯康星州将被用来评估有机氮的吸收不同的菌根真菌和植物。这些信息将与菌根植物的实验室研究相结合，以提供第一个现实的和定量的有机氮使用的估计。 该项目正在开发的新方法将确定不同生态系统和不同种类的菌根真菌对有机氮的利用模式是否不同。这项工作将开发和完善量化植物和菌根真菌对有机氮的利用的新方法，这将改变研究人员对土壤中氮循环及其与土壤碳的联系的看法。这对森林管理有影响。教育工作将涉及与当地几位高中教师合作，扩大他们对户外教室的使用，并使用真菌作为生物学教学的工具。对公众的宣传还将包括教育阿巴拉契亚山俱乐部（AMC）的自然学家在森林中的真菌作用，以及领导AMC自然散步。该项目将包括培养一名博士。学生和几名本科生，包括从伊丽莎白城州立大学招收学生，这是一所历史上与联合国大学有着密切学术联系的黑人大学。

Much of plant nitrogen supply, particularly for trees, is supplied through symbiotic (mycorrhizal) fungi that obtain sugars from their host trees and in return transfer nitrogen. However, methodological difficulties have limited quantification of the role that mycorrhizal fungi play in meeting plant nitrogen demands. In this project, ratios of carbon and nitrogen isotopes from two field experiments at Duke University and at Rhinelander, Wisconsin will be used to assess organic nitrogen uptake by different mycorrhizal fungi and plants. This information will be combined with laboratory studies on mycorrhizal plants to provide the first realistic and quantitative estimates of organic nitrogen use. New methodologies being developed for this project will determine whether patterns of organic nitrogen use differ across ecosystems and across species of mycorrhizal fungi.This work will develop and perfect new methods to quantify organic nitrogen use by plants and mycorrhizal fungi which will transform how researchers think about nitrogen cycling in the soil and its connections to soil carbon. This has implications for forest management. Educational work will involve collaboration with several local high school teachers to expand their use of outdoor classrooms and use of fungi as a tool to teach biology. Outreach to the public will also include educating Appalachian Mountain Club (AMC) naturalists on fungal roles in forests as well as leading AMC nature walks. The project will involve training for a Ph.D. student and several undergraduates, including recruitment of students from Elizabeth City State University, a historically black institution with strong academic ties to UNH.