The Effects of Cultivation Practices and Fertilizer Use on the Mitigation of Greenhouse Gas Emissions from Kentucky Bluegrass Athletic Fields.

Greenhouse gas emissions are known to contribute to global warming and thus climate change. The influence of cultural management practices need to be evaluated to determine the impact they have in contributing to greenhouse gas emissions. A two-year field study on a Kentucky bluegrass (Poa pratensis) football field evaluating cultivation practices (hollow tine aerification, verticutting, and control) and fertilizer use (220 kg N ha-1 yr-1 using Urea and 0 kg N ha-1 yr-1) on greenhouse gas emissions. Samplings occurred weekly throughout the summer and fall of 2013-2014. Gas samples were taken using a vented closed gas chamber for 40 minutes following the USDA-ARS GRACEnet methods. Soil temperature, soil moisture, canopy greenness, and turfgrass quality were also collected. Cultivation practice was significant (p<.05) for 5 dates and fertilizer use was significant (p<.05) for 7 dates in 2013 where verticutting and the lack of urea decreased CO2 emissions in 2013; similar results were observed in 2014. Cultivation practice was significant (p<.05) for only 4 dates during 2013-2014 for N2O. Fertilizer use was significant (p<.05) all dates in 2014 where urea applications increased N2O emissions. For CH4, cultivation practice was not significant in 2013-2014. Fertilizer use was significant (p>.05) for only two dates in 2013 and four dates in 2014 where urea applications increased CH4 emissions. For canopy greenness, cultivation practice was significant (p<.01) for all dates in 2013-2014 except for two dates in August 2013 and July 2014. The use of fertilizer was significant for all dates in 2013-2014 for canopy greenness except for one date. Fertilizer use significantly (p<.0001) increased turfgrass quality for all dates in 2013-2014. The results from this study will provide information about cultivation practices and fertilizer usage that minimize greenhouse gas emissions which can be utilized to evaluate the environmental efficacy of our current cultural management strategies.