CAREER: Large-scale nitrogen cycles and underrepresented groups: A plan for advancement

氮是地球上最重要的资源之一，影响着从粮食生产到全球气候系统的方方面面。该项目将使用天然存在的氮（15N）和氧的同位素来研究从沙漠到温带雨林等一系列陆地生态系统中氮循环的控制。现场和实验室实验将用于测试15N的富集是否可以用于量化氮向气态形式的转化，这是氮循环的一部分，在大空间尺度上特别难以测量。这些实验结果将用于参数化和改进现有的全球氮循环模型，最终目标是开发大空间尺度上研究陆地氮循环的新方法。这项工作对理解氮在气候变化中的作用具有重要意义，因为氮对二氧化碳吸收的影响以及氧化亚氮的自然来源的重要性。氧化亚氮是一种含氮分子，是一种比二氧化碳更强的温室气体。种族和文化多元化的学生将积极参与拟议的研究。PI是加州大学戴维斯分校两个项目的校内顾问：生态教育、多样性和可持续性战略（SEEDS）和环境。这些项目的使命是通过激发和培养未被充分代表的群体的兴趣，使生态学专业多样化和进步。SEEDS和environments的学生将参与这项研究，从而促进本科和高中水平的智力/文化协同作用。一名博士后研究员、两名研究生和五名本科生将参与这项研究，进一步发展未来的劳动力。

Nitrogen is one of the most important resources on Earth, affecting everything from food production to the global climate system. This project will use naturally occurring isotopes of nitrogen (15N) and oxygen to examine controls on nitrogen cycling across an array of terrestrial ecosystems ranging from desert to temperate rainforest. Field and laboratory experiments will be used to test whether enrichment of 15N can be used to quantify conversion of nitrogen to a gaseous form, a part of the nitrogen cycle that has been particularly difficult to measure at large spatial scales. Results of these experiments will be used to parameterize and improve an existing model of the global nitrogen cycle, with the ultimate goal of developing new ways to study terrestrial nitrogen cycles at large spatial scales. This work has implications for understanding the role of nitrogen in climate change because of the influence of nitrogen on the uptake of carbon dioxide and because of the importance of natural sources of nitrous oxide, a nitrogen-containing molecule that is a much more potent greenhouse gas than carbon dioxide. Ethnically and culturally diverse students will be actively engaged in the proposed research. The PI is the on-campus (UC Davis) advisor to two programs: Strategies for Ecology Education, Diversity and Sustainability (SEEDS) and EnvironMentors. The mission of these programs is to diversify and advance the profession of ecology through opportunities that stimulate and nurture the interest of underrepresented groups. Students in SEEDS and EnvironMentors will be engaged in this research, thereby promoting intellectual/cultural synergism at both undergraduate and high-school levels. Additional development of the future workforce will result from involvement of a postdoctoral researcher, two graduate students, and five undergraduates in this research.