Significant losses of nitrogen as nitrous oxide, a potent greenhouse gas, can occur during soil freeze/thaw events over winter from heavily fertilized agricultural lands. We are measuring the extent of nitrous oxide emissions from soils at the Harford Farm in Dryden, NY, and evaluating different soil and crop management practices that can help mitigate these losses.

Nitrous oxide is a potent greenhouse gas that is produced by bacteria in the process of denitrification in soils. Denitrification occurs under anaerobic conditions, such as those found in soils when frozen water and snow thaw during warming events in winter. The combination of high soluble organic C, nitrate-N and anoxic conditions lead to denitrification. Both nitrous oxide and molecular N are products of the dentrification reactions. The ratio of nitrous oxide to molecular N that results depends on the enzymatic capacity of the soil microbial community and soil conditions. Management practices need need to be developed to lower nitrous oxide emissions, thus lowering the impact of farming systems in the Northeast on global climate change.

We are working to understand the extent of nitrous oxide losses on a local farm and the conditions needed to decrease or mitigate these losses. We are measuring nitrous oxide losses during soil freeze/thaw events in plots receiving different crop and soil management treatments. We aim to identify the best management strategies for reducing the likelihood of N losses via denitrification, thus lowering greenhouse gas emissions from agricultural lands.

Global climate change is a pressing problem shared by all. Agriculture can be a major contributor to greenhouse gas emissions if soils are not properly managed. The alternative soil and crop management practices we are evaluating are aimed at helping farmers better manage their lands to reduce off-site impacts, particulary those that lead to water pollution and greenhouse gas emissions.