Abstract:Returning maize straws to soil is an important strategy to increase soil productivity, however, it can affect the mineralization process of soil organic matter (SOM), which is known as the priming effect, and then can further influence the turnover and stability of soil organic carbon (SOC). Thus, suitable maize straw addition is the key factor to improve soil potential productivity associated with high efficiency and friendly environment. In this study, an incubation was carried out to study the effects of maize straws at rates of 0(CK), 1%, 5% and 9% of dry soil on CO2 emission and priming effect of SOM. Results showed that the rate and accumulation of CO2 flux displaced parabolic curves with time across all treatments. At the early incubation, the rates of CO2 flux of all treatments were in an order of 9%>5%>1%>CK, but the rate of CO2 flux was higher in 5% treatment than in 9% treatment at the later incubation, and tended to be similar for all the treatments at the end. Higher accumulative CO2 emission in 5% treatment than in 9% treatment indicated that the community and activity of soil microbe were activated by maize straw addition. Negative priming effect with maize straws was observed during incubation, which might induce SOC accumulation. All these indicated that maize straws is beneficial to SOC in yellow-brown soil, with the adding rate of 9% of soil dry weight being better in this study.