中文摘要：

基于静态箱法和气井法分别测定新疆棉田覆膜位置的土壤CO2通量和CO2浓度.结果表明：土壤CO2通量和CO2浓度时间变化特征与土壤温度变化趋势一致,均表现为7月较高,10月最低.观测期内,棉田土壤CO2累积排放量非覆膜处理为2032.81 kg C·hm^-2,覆膜处理为1871.95 kg C·hm^-2;而1 m深度内土壤CO2浓度非覆膜处理为2165-23986μL·L^-1,覆膜处理为5137-25945μL·L^-1,即覆膜减少了棉田土壤排放CO2的同时增加了土壤CO2积累量.覆膜和非覆膜处理下不同深度土壤CO2浓度和CO2通量的相关系数分别为0.60-0.73和0.57-0.75,表明地表释放的CO2强烈依赖于土壤剖面储存的CO2.覆膜和非覆膜处理下Q10值分别为2.77和2.48,表明覆膜处理下的土壤CO2通量对土壤温度变化的响应更敏感.

英文摘要：

A field study was conducted to compare soil C02 efflux and CO2 concentration between mulched and non-mulched cotton fields by using closed chamber method and diffusion chamber technique. Soil CO2 efflux and CO2 concentration exhibited a similar seasonal pattern, decreasing from July to October. Mulched field had a lower soil C02 efflux but a higher CO2 concentration, compared to those of non-mulched fields. Over the measurement period, cumulative CO2 efflux was 1871.95 kg C·hm^-2 for mulched field and 2032.81 kg C ·hm^-2 for non-mulched field. Soil CO2 concentration was higher in mulched field （ ranging from 5137 to 25945 μL·L^-1 ） than in non- mulched field （ ranging from 2165 to 23986μL·L^-1 ）. The correlation coefficients between soil CO2 concentrations at different depths and soil CO2 effluxes were 0.60 to 0.73 and 0.57 to 0.75 for the mulched and non-mulched fields, indicating that soil CO2 concentration played a crucial role in soil CO2 emission. The Q10 values were 2.77 and 2.48 for the mulched and non-mulched fields, respectively, suggesting that CO： efflux in mulched field was more sensitive to the temperature.