**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** NITROGEN CAN BE LOST FROM AGRICULTURAL SOILS THROUGH MULTIPLE PATHWAYS, INCLUDING LEACHING OF NITRATE IN GROUNDWATER, AND EMISSIONS OF THE GREENHOUSE GAS NITROUS OXIDE (N2O). NITRIC OXIDE IS A TRACE GAS THAT IS PRODUCED BY SOIL MICROBES AND EMITTED TO THE ATMOSPHERE, WHERE IT IS IS IMPORTANT IN THE FORMATION OF OZONE AND PARTICULATE MATTER POLLUTION. NO EMISSIONS ARE AN IMPORTANT LOSS PATHWAY FOR NITROGEN FROM AGRICULTURAL SYSTEMS, AND THESE EMISSIONS CAN INCREASE SUBSTANTIALLY WITH THE ADDITION OF FERTILIZER. WINTER NOX (NO + NITROGEN DIOXIDE (NO2)) EMISSIONS FROM NON-URBAN SOURCES HAVE BEEN SUGGESTED TO BE AN IMPORTANT PRECURSOR TO PARTICULATE MATTER POLLUTION OVER THE MIDWESTERN U.S. UNFORTUNATELY, AGRICULTURAL NOX EMISSIONS IN THE MIDWESTERN U.S. ARE POORLY CONSTRAINED OVER DURING WINTER. IN PARTICULAR, THE EFFECTS OF FREEZE-THAW EVENTS ON SOIL NO EMISSIONS ARE NOT WELL UNDERSTOOD, EVEN THOUGH THEY ARE GLOBALLY IMPORTANT SOURCES OF N2O.WE WILL CONDUCT A SERIES OF LINKED ACTIVITIESTO IMPROVE OUR UNDERSTANDING OF SOIL NO EMISSIONS DURING WINTER AS WELL AS THE REST OF THE GROWING SEASON: 1) WE WILL USE THE EDDY COVARIANCE TECHNIQUE AT THE PLATTE RIVER - HIGH PLAINS AQUIFER LONG TERM AGRICULTURAL RESEARCH SITE (PR-HPA) TO CONDUCT CONTINUOUS, HIGH-FREQUENCY MEASUREMENTS NOX FLUXES FOR ONE YEAR--THE FIRST SUCH HIGH FREQUENCY OBSERVATIONS OF NOX FROM AN AGRICULTURAL SYSTEM IN THE UNITED STATES. 2) WE WILL USE HIGH RESOLUTION SATELLITE-BASED OBSERVATIONS OF NO2 TO EVALUATE THE IMPACT OF FREEZE-THAW EVENTS ON REGIONAL ATMOSPHERIC COMPOSITION TO DETERMINE IF THEY ARE AN IMPORTANT SOURCE OF NOX IN THE MIDWESTERN U.S. 3) WE WILL CONDUCT LABORATORY INCUBATIONS OF SOILS FROM CONVENTIONAL AGRICULTURAL MANAGEMENT AND MANAGEMENT THAT INCORPORATES A GREATER CONSERVATION APPROACH AT PR-HPA TO EVALUATE BIOGEOCHEMICAL AND MICROBIAL RESPONSES TO FREEZE-THAW EVENTS, AND TO IDENTIFY THE PHYSICAL AND BIOLOGICAL FACTORS THAT ARE RESPONSIBLE FOR FREEZE-THAW EMISSIONS OF NO. THE OUTCOMESOF THIS PROJECT WILL ADDRESS GOALS A) AND B) OF THE SOIL HEALTH PROGRAM AREA PRIORITY, AS WELL AS BOTH SUGGESTED TOPICS FOR FY2020: THE EFFECTS OF MANAGEMENT PRACTICES ON SOIL MICROBIAL COMMUNITY FUNCTION AND THE ASSESSMENT OF APPROACHES FOR ENHANCING UNDERSTANDING OF BIOGEOCHEMICAL PROCESSES CONTRIBUTING TO AGRICULTURAL SUSTAINABILITY.

Research Foundation Of The City University Of New York, New York NY

Investigators