Greenhouse gas fluxes from turfgrass systems: Species, growth rate, clipping management, and environmental effects

Turfgrass systems can be an important source or sink for greenhouse gases (GHG), including carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4). Further research is required in turfgrass systems; therefore, our objectives were to evaluate the effects of turfgrass species, growth rate, clipping management, and environmental conditions on GHG emissions. Greenhouse gas fluxes were measured in two separate field experiments in West Lafayette, IN. Experiment 1 investigated GHG flux in three cool‐season (C3) and two warm‐season (C4) turfgrass species during two growing seasons. Experiment 2 investigated fluxes in two C3cultivars with varying growth rates and under different clipping management regimes. The C3turfgrasses had the highest mean CO2flux rates ranging from 0.373 to 0.431 g CO2‐C m−2h−1compared with 0.273 to 0.361 g CO2‐C m−2h−1for C4turfgrasses. Mean hourly N2O flux rates ranged from 43.3 to 50.9 μg N2O‐N m−2h−1for C3compared with 11.1 to 14.4 μg N2O‐N m−2h−1for C4turfgrasses. Methane flux was more variable across time, but overall C4turfgrasses were more likely to be a CH4source, whereas C3turfgrasses were often a CH4sink. Growth rate and grass clipping management treatments had negligible impact on measured GHG flux. The differences in management practices specific to C3and C4turfgrasses had the largest impact on GHG flux. Results indicate the impact and importance of turfgrass species selection on GHG flux and also provide more information on our overall understanding on carbon and nitrogen cycling in urban soils. Turfgrass systems can be either a source or a sink for greenhouse gases.Further research is required on the effects of turfgrass species, growth rate, and clipping management.Higher CO2and N2O fluxes occurred in C3turfgrasses compared with C4turfgrasses.Management factors specific to C3or C4turfgrasses had the largest impact on GHG flux.Growth rate and grass clipping management had negligible impact on GHG flux.