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.
