Western Farm Press. 13 March 2012. In organic agriculture, nutritional building blocks like nitrogen, carbon and phosphorous are introduced via organic matter to improve soil over time. But when these nutrients are released as gases into the air or in storm water runoff, they can pollute water sources and contribute to greenhouse gas buildup. For farmers, the loss of valuable nutrients affects the bottom line because they must be replaced with more costly inputs.

Washington State University scientists are developing a series of experiments to determine the types and amounts of gases emitted by organic cropping systems.  They are working on practices that give growers a way to manage inputs that give plants the nutrition they need while not creating pollution. They are comparing how different organic farming systems with a history of different amendments and tillage frequency affect releases of carbon dioxide and nitrous oxide, two major greenhouse gases.

Both tillage and type of amendment affect the soil ecosystem, but they want to know how the microbes in these different ecosystems affect the release of greenhouse gases from the soil. The research may improve the understanding of how carbon and nitrogen cycle between land, air and water in vegetable and row crop farming systems in the Pacific Northwest and Midwest.

While a great deal is known about crop production and nitrogen fertilizers, knowledge of the way soil microorganisms regulate the cycling of nutrients is limited. read more