摘要：Data on greenhouse gas emission levels associated with fertilization applied in smallholder paddy rice farms in Ghana are scanty. The current study investigated fertilization types to determine their eco-friendliness on yield, Global Warming Potential (GWP) and Greenhouse Gas Intensity (GHGI) in a major rice season in the forest zone of Ghana. In total, five treatments were studied viz Farmer Practice (BAU); Biochar + Farmer Practice (BAU + BIO); Poultry Manure + Farmer Practice (BAU + M); Biochar + Poultry Manure + Farmer Practice (BAU + BIO + M); and Control (CT). Fluxes of methane (CHsub4/sub) and nitrous oxide (Nsub2/subO) were measured using a static chamber-gas chromatography method. Nsub2/subO emissions at the end of the growing season were significantly different across treatments. BAU + BIO + M had highest Nsub2/subO flux mean of 0.38 kgNhasup−1/supdaysup−1/sup (±0.18). BAU + M had the second highest Nsub2/subO flux of 0.27 kgNhasup−1/supdaysup−1/sup (±0.08), but was not significantly different from BAU at ip/i 0.05. BAU+BIO recorded 0.20 kgNhasup−1/supdaysup−1/sup (±0.12), lower and significantly different from BAU, BAU + M and BAU + BIO + M. CHsub4/sub emissions across treatments were not significantly different. However, highest CHsub4/sub flux was recorded in BAU+BIO at 4.76 kgCHsub4/subhasup−1/supdaysup−1/sup (±4.87). GWP based on seasonal cumulative GHG emissions among treatments ranged from 5099.16 (±6878.43) to 20894.58 (±19645.04) for CHsub4/sub and 756.28 (±763.44) to 27201.54 (±9223.51) kgCOsub2/subeq hasup−1/supSeasonsup−1/sup for Nsub2/subO. The treatment with significantly higher yield and low emissions was BAU + M with a GHGI of 4.38 (±1.90) kgCOsub2/subeqkgsup−1/sup.
