秸秆还田对东北黑土区稻田温室气体排放特征和水稻产量形成的影响OA北大核心

Straw returning is an important agricultural management practice to improve soil fertility and maintain agroecosystem health,but its impact mechanism on greenhouse gas emissions under conventional fertilization management remains unclear,especially in the paddy ecosystem of the black soil region in Northeast China.This study aims to investigate the effects of straw returning and conventional fertilization on methane(CH4),nitrous oxide(N2O)emissions,and rice yield in this region,so as to identify suitable field management measures for low-carbon and high-yield rice production.Taking"Jijing 83"as the research object,four treatments are set up:CK(no straw returning,no fertilization),FP(no straw returning,conventional fertilization),S(straw returning,no fertilization),and SF(straw returning,supplemental fertilization).CH4 and N2O emission fluxes in paddy fields are monitored continuously by the static dark chamber-gas chromatography method to determine rice yield and the emission characteristics of CH4 and N2O during the rice growth period.The results show that:(1)CH4 and N2O emission fluxes are influenced by straw returning and fertilization,and the greenhouse gas emission fluxes vary across different rice growth stages.(2)Compared with treatments without straw returning,treatments with straw returning significantly increase the greenhouse gas emission fluxes of paddy fields.The global warming potential of treatments S and SF is 68.0-305.9%and 104.0-162.4%higher than that of the CK treatment,respectively.(3)Straw returning greatly improves rice yield,and the yield of the S treatment is significantly higher than that of the CK treatment,with increases of 15.9%and 17.3%over two years,respectively.These results provide theoretical support for efficient straw utilization and nutrient management for achieving high and stable yields.