Coupling Effects Of Reduced Tillage And Straw Covering On Soil Carbon Emission In Wheat-Maize Intercropping System

Agricultural activities are important parts of ecosystem carbon process, reducing greenhouse gas emission has huge potential in alleviating global warming. In order to explore more effective carbon reduction planting patterns, field experiments were conducted to study the correlation between farmland carbon emissions and decisive factors in reduced tillage and straw mulching with plastic film recycling integrated into the same intercropping mode. The sustainability of different modes was evaluated to provide basis of theory and practice for the establishment of the oasis irrigation area of carbon emission reduction measures. The main results were as follows:1. Straw covering combined with plastic film mulch for two years under reduced tillage(NTSI) can significantly reduced total soil CO2 emission in growth period. The total soil CO2 emission in growth period of NTSI was 3948.4 kg?hm-2. Compared with conventional intercropping mode, conventional monocropping maize and plastic film mulch for two years decreased by 16.6%, 35.4% and 28.0%.2. It showed that decreased of soil temperature, crop dry matter accumulation before wheat harvest and increased of soil moisture were significantly relative to decreasing emissions of straw covering combined with plastic film mulch for two years under reduced tillage(NTSI). The average soil temperature of NTSI was 19.0 ℃. Compared with conventional intercropping mode, conventional monocropping maize and plastic film mulch for two years decreased by 5.3%, 8.2%, 4.5%. The soil water content of NTSI reaching to 159 d above 18% level. Compared with conventional intercropping mode, conventional monocropping maize and plastic film mulch for two years decreased by 31 d, 95 d, 80 d and it laid a good soil moisture environment for high crop yield. Compared with wheat and maize of conventional tillage, crop dry matter accumulation of NTSI increased by 3.2% and 7.1%. It showed that NTSI had a significantly crop dry matter accumulation increase advantage.3. Compared with conventional intercropping mode and monocropping maize, straw covering combined with plastic film mulch for two years under reduced tillage(NTSI) can significantly increased yield, crop water use efficiency and carbon emission efficiency. The sustainable evaluation index of NTSI was the highest, reaching to 0.99. Compared with conventional intercropping mode, conventional monocropping maize and plastic film mulch for two years increased by 16.5%, 25.3% and 22.2%. NTSI was the most suitable cropping pattern with low carbon emission and high efficient.