Effect of Rice Straw Incorporation on Rice Yield and Carbon Pool Management Index under the Application of Farm Mechanization

A localization field experiment,designed with four freatments,i.e.CK,NPK,rice straw incineration and chemical fertilizers(SINPK),total rice straw incorporation and chemical fertilizers(SNPK),was conducted to examine the effect of rice straw incorporation on rice yield and carbon pool management index under the conditions of equal Nitrogen,phosphorus and potassium nutrient.The results showed that rice straw returned to field increased the next year's early rice yield,and compared with NPK and SINPK treatments,the production increased significantly by 3.4%~4.3%,the late rice yields of NPK and SNPK treatments were similar,and lower than that of SINPK treatment.Compared with NPK and SINPK treatments,the contents of all types of soil carbon and carbon pool management index(CPMI) were improved when rice straw was returned to the soil,the active carbon,mineralized carbon and CPMI increased by 5.93%~7.87%,27.14%~67.55% and 11.41%~21.49%.Correlation analysis revealed that the CPMI and yield of double cropping early rice and late rice had significant parabola correlation(r=0.982 9* and r=0.982 8*).