Effects Of Tillage And Application Of Fertilizer On Paddy Soil Carbon Emission And Carbon Balance

Agriculture is an important source of greenhouse gases, greenhouse gas emissions of agricultural sources of greenhouse gas emissions, accounting for 17% of the total; methane emissions from agricultural activities account for the total methane emissions in china 50.15%. Agriculture is an important source of greenhouse gases in china. Currently efforts are being made for a variety of measures to effectively control greenhouse gas concentrations rise.carbon emissions and carbon budget in different tillage and fertilization were studied through field experiments and laboratory.This study was conducted to mainly studied the effects of tillage and fertilizer on soil physical and chemical properties, soil carbon emissions,rice yield,those studies would benefit to evaluate the impact of the changes of paddy farming systems on carbon cycling in the paddy ecosystem.The main results are summarized as follows:1.Tillage significantly affected the soil organic carbon, no-tillage significantly increased the total organic carbon in the paddy soil surface (0-5 cm).2.1n the rice growth period,the CO2 emission flux of each treatment was 1079.05 g/m2,927.68 g/m2,911.09 g/m2,774.55 g/m2, followed by CTF,NTF,NTO,CTO, Fertilization significantly increased CO2 emissions;tillage did not affect the CO2 emissions in the paddy soil, but one week after tillage, no-tillage treatment was significantly lower than emissions from tillage treatment, which may the soil aggregates was undermined by tillage, Made the physical protection of soil carbon to be released, The Interaction of tillage and fertilization significantly affected CO2 emissions.Correlation analysis showed that, CO2 emissions in soil temperature, soil organic C, biomass was significantly positively correlated, indicating that the soil temperature, soil organic C and aboveground biomass were important factors of CO2 emissions.3. During rice growth, the CH4 emission flux of each treatment was 123.64 g/m2,97.66 g/m2,93.17 g/m2,87.3 g/m2, followed by NTO,CTF,CTO,NTF. Tillage and fertilization did not affect the CH4 emissions in the paddy soil, however, tillage significantly increased CH4 emissions in the seedling - tillering stage and booting-maturing stage.Correlation analysis showed that, CH4 emissions in soil temperature was significantly positively correlated,methane emissions did not has correlation with TOC,WSOC,aboveground biomass. It shows that CH4 emissions from paddy soil was a comprehensive reflection of the process soil, so evaluation the affect of tillage on the CH4 emissions must be integrated into the structure and biochemical properties of soil influence.4. Fertilization significantly increased the yield of rice. Carbon budget analysis showed that tillage significantly affected C budget, the Net input of NTO and NTF treatment were ere 515.9,700.3 g/m2, higher 167.2 g/m2,178.2 g/m2 than CTO and CTF;fertilization increased net C input 184.4g/m2,173.4g/m2, no-tillage and fertilization can increase the carbon revenues, with a strong carbon sink effects.However, the no-tillage significantly decreased the rice yield, indicating that the current situation no-tillage was not a low-carbon and high-yield technology, how to achieve low-carbon and high-yield in no-tillage paddy will be our focus of future research.