采用定位试验,系统研究翻耕(CT)、旋耕(RT)、免耕不覆盖(NT)3种不同耕作措施下土壤CO2排放速率,并对CO2排放速率和10cm土壤温度进行回归模拟。结果表明:夏玉米生育期CO2排放速率表现为翻耕(CT)〉旋耕(RT)〉免耕不覆盖(NT),平均分别为585.675、457.875和184.95mg·m-2·h-1。并且3种耕作措施之间差异均达到显著水平(P〈0.05);各处理夏玉米生育期CO2排放速率与土壤温度呈显著正相关;NT、RT和CT处理CO2排放速率与10cm地温相关系数分别为0.624、0.609和0.606。CO2排放速率和土壤温度呈指数函数关系(P〈0.05),利用10cm地温对夏玉米生育期农田CO2排放通量进行估算表明,CT、RT和NT处理CO2排放量分别为1.47、1.15和0.46kg·m-2。
Based on a short-term experiment,this paper investigated the CO2 flux in summer corn growth season under three treatments including moldboard plow tillage(CT),rotary tillage(RT) and no tillage(NT),and simulated the correlation between the flux and soil temperature by regression method.The results indicated that under different tillagemeasures,the average CO2 emission rate in summer corn growth season was in the order of moldboard plow tillage(CT) rotary tillage(RT) no-tillage(NT),with the value being 585.675,457.875 and 184.95 mg·m-2·h-1,respect ively.There was a significant exponential correlation between CO2 flux and soil temperature at the depth of 10 cm.The correlation coefficients were 0.624 under NT,0.609 under RT and 0.606 under CT treatments respectively.Simulating with the soil temperature at the depth of 10 cm,the CO2 flux in summer corn growth season was estimated as 1.47 kg·m-2 under CT,1.15 kg·m-2 under RT,and 0.46 kg·m-2 under NT.