Research in my lab examines carbon, nitrogen, and water dynamics in terrestrial ecosystems, with an emphasis on responses to global change. Recent projects include: 1) the response of carbon and nitrogen cycles to elevated carbon dioxide in a Mojave Desert ecosystem, 2) the impact of invasive species on soil carbon and nitrogen dynamics, 3) mechanisms controlling plant nitrogen isotope composition, and 4) carbon isotope ratios of microbial communities to elucidate patterns of substrate use. Current research is focused on past and present patterns of atmospheric deposition and plant and ecosystem responses, and my students and I are part of the BioEarth (http://www.cereo.wsu.edu/bioearth/) and Nitrogen Systems: Policy-oriented Integrated Research and Education (NSPIRE) IGERT (http://igert.nspire.wsu.edu/) programs. Our research makes extensive use of both field and laboratory experiments, with emphasis on measurements of natural stable isotope ratios. I also direct the WSU stable isotope core laboratory (http://www.isotopes.wsu.edu/), and serve on the Executive Committee of the WSU Center for Environmental Research, Education and Outreach (CEREO) http://www.cereo.wsu.edu/.