Greenhouse Gas Emissions from an Ornamental Crop as Impacted by Two Best Management Practices: Irrigation Delivery and Fertilizer Placement1

Abstract Agriculture is one of the largest contributors of greenhouse gas (GHG) emissions. To date, much work on reducing GHG emissions has centered on row crops, pastures, forestry, and animal productionsystems, while little emphasis has been placed on specialty crop industries such as horticulture. In this horticulturecontainer study, Japanese boxwood ( Buxus microphyllaSiebold & Zucc.) was used to evaluate the interaction of irrigation (overhead vs drip) and fertilizer placement (dibble vs incorporated) on GHG emissions (CO2, N2O, and CH4). Plants were grown in 11.4 L (#3) containers with a 6:1 pine bark:sand substrate with standard amendments. All containers received 6.35 mm (0.25 in) water three times daily. Gas samples were collected in situ using the static closed chamber method according to standard protocols and analyzed using gas chromatography. Total cumulative CO2 loss was not affected by differences in irrigation or fertilizer placement. Total cumulative N2O efflux was least for drip-irriga...