不同比例有机肥替代化肥对夏玉米氮肥利用率及N2O排放的影响OA北大核心CSTPCD

This study was set up to explore the effects of different organic fertilizer substitution ratios on maize yields and plant uptake and utilization of nitrogen fertilizers in 2022 and 2023 for two consecutive years,including five treatments:No fertilizer(CK),conventional fertilizer(CF),organic fertilizers substituting 10％nitrogen fertilizer(FM1),organic fertilizer substituting 30％nitrogen fertilizer(FM2)and organic fertilizer substituting 50％nitrogen fertilizer(FM3).The results showed that compared with CF treatment,the two-year average soil bulk density of FM1,FM2,and FM3 treatments decreased by 1.43％,2.15％,and 4.67％,respectively.The two-year average soil porosity increased by 2.07％,2.60％,and 5.51％,respectively.The two-year average nitrate nitrogen content increased by 9.67％,14.86％,and 11.01％,respectively.Compared with CF treatment,FM1 treatment increased the two-year average dry matter accumulation and yield of corn plants by 3.41％and 3.42％over the two years,while FM3 treatment decreased by 3.25％and 6.73％,respectively.Compared with CF treatment,FM1 treatment increased the two-year average nitrogen accumulation by 4.49％over two years,and the two-year average nitrogen fertilizer utilization efficiency and agronomic utilization efficiency increased by 13.62％and 6.1 1％respectively.The two-year average economic benefit increased by 2.87％over two years,and the two-year average nitrogen dioxide(N2O)emission decreased by 16.41％over two years.Moreover,FM1 treatment increased the nitrogen accumulation in stems and leaves.When the proportion of organic fertilizer substituting chemical fertilizer was 30％or more(FM2,FM3 treatments),the yield and nitrogen fertilizer utilization efficiency were significantly reduced,and the economic benefit was reduced.In summary,substituting 10％chemical fertilizer with organic fertilizer can significantly improve nitrogen fertilizer utilization efficiency and reduce N2O emission,making it a recommended proportion for achieving nitrogen fertilizer reduction and green and high-yield agriculture.