147B Plant Science
I have a broad interest in using science to develop sustainable societies that provide for all people while preserving natural resources and biosphere integrity for future generations. Achieving this goal requires an understanding of the fundamental nature of managed ecosystems and the mechanisms that govern human-environmental interactions. The prospect of developing food production systems that enhance ecological processes while contributing to sustainability is a key idea guiding all facets of my work.
My research group conducts studies of soil nutrient cycling processes in agroecosystems at scales ranging from the rhizosphere to farm and watershed scales. We investigate mechanisms within the plant-soil-microbial continuum that control ecosystem processes such as energy flows and nutrient cycling. Current research projects are focused on achieving a better understanding of the biotic and abiotic mechanisms regulating linkages between carbon and nitrogen cycles, with particular emphasis on the following processes: 1) symbiotic biological N-fixation, 2) decomposition and mineralization and 3) microbially-mediated N transformations such as nitrification, denitrification. Our work is also geared toward the development of management practices that improve soil quality while optimizing carbon and nitrogen cycling in intensive horticultural systems. Most of our research involves some degree of interdisciplinary collaboration. We are currently working with colleagues from molecular microbial ecology, resource economics, environmental sociology, biogeochemical modeling and weed ecology.
I place a high value on my interactions with farmers and other practitioners. Over the years, these interactions have had considerable influence on the research that I have undertaken. My lab group carries out extension and outreach activities in conjunction with research through partnerships that entail the active participation of farmers. Currently we are engaged in on-farm research that addresses soil and nutrient management problems. Our educational activities are aimed at farmers who rely on green manures as nitrogen sources or who are interested in using cover crops in their farming system.
The graduate and undergraduate courses I teach integrate ecological and agricultural knowledge. My over-arching goal in teaching and mentoring students is to contribute to the development of scientists who will be equipped to address the global challenges we face in agriculture and environmental management. In my classes we engage in participatory, independent and collaborative learning and work to improve key life skills including critical and synthetic thinking, verbal and written communication. Graduate seminars that I have offered include 1) Decomposition, 2) Sustainability: Ethical, socioeconomic and biophysical dimensions, 3) Agroecosystems: Research and design.