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One of the major causes: nitrogen runoff in the Midwest from agricultural activities up the Mississippi River that drain into the Gulf of Mexico.

"On average, about half of nitrogen fertilizer that is applied to agricultural crops is lost to the environment," said Laurie Drinkwater, professor of horticulture at Cornell University. But those who pollute don't pay the costs associated with resource degradation, and responses to address the problem don't always target the right problem in the right place. Or do they?

To find out, Drinkwater, as the lead scientist, and a team of colleagues at five other institutions have been awarded $1.6 million over three years from a National Science Foundation program, called Biocomplexity in the Environment -- Dynamics of Coupled Natural and Human Systems. The idea is to determine the correlation between biogeochemical processes in agriculture, such as nitrogen pollution and carbon/nitrogen cycling, and institutional processes, such as research and extension efforts, changes in regulations, property rights and subsidies and responses of businesses, public agencies and civil society organizations.