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Biochar has the potential to mitigate greenhouse gases emissions (GHG) from soils.A laboratory incubation study was conducted to compare the effects of soil amendments with a range of biochar feedstocks and biochar on CO2, N2O and CH4 emissions.The feedstocks included coffee grounds, wood pellets and horse bedding compost.The biochars were prepared from these feedstocks by gasification at 700℃ under low oxygen conditions.Biochar and its feedstock were incorporated into a silt loam soil (at 22 % gravimetric moisture content) at the application rate of 0.75% by weight and incubated for 30 days at ambient temperature (22 ℃).Seven treatments were studied: soil;soil + coffee grounds;soil + coffee ground biochar;soil + wood pellets;soil + wood pellet biochar;soil + horse bedding compost and soil + horse bedding compost biochar.CO2, N2O and CH4 evolution were measured after 2, 9, 16, 23, 21 and 30 days of incubation by gas chromatography (GC).The data show that amendments with the coffee ground and wood pellet feedstocks significantly increased CO2 respiration rates compared to the unamended soil.In contrast, amendments with the biochars did not affect rates of N2O and CH4 except at day 2 when N2O emission was significant greater than the unamended soil.However, horse bedding compost addition did not have effect on CO2 respiration rate compared to coffee grounds, wood pellets feedstock and as same as biochar amendment did.Further, carbon mineralization was significant greater (23.3% and 24.7% for wood pellets and coffee grounds, respectively.) in the biochar feedstock amendments than biochar amended soils, whereas biochars reduced around 0.3 % carbon mineralization compared to the unamended soil.In conclusion, this short term incubation study has shown that biochar, as a soil amendment, has potential to sequester carbon and it does not have impact on either N2O or CH4 emissions.