Effect Of Fertilizing Biochar With Starw And Manure On Soil Aggregate And Fractions Of Organic Carbon In Yellow Clunamon Soil

The yellow cinnamon soil is distributed in Henan Province with positive conditions to crop growth such as superior hydrothermal,great depth of soil,appropriate p H,wide vegetative suitability and high potential in crop yield.However,heavy soil texture gives rise to instability of the yield.In this circumstance,the fertilization technology for improving the yield of crops and the quality of soil is necessary.It has been found that biochar promotes formation of soil aggregates(>0.25 mm)and increases content of the organic aggregate carbon.Therefore,in this research,applying biochar with crop straw and organic manure technically and practically evaluated variations of the yield and aggregates of the yellow cinnamon soil characterized by the chemical and physical properties and organic carbon component,which expected to reveal mechanism of the aggregate formation and fate of organic carbon in the soil.The main results are followed as:1 Single biochar and simultaneous application of biochar with crop straw,organic manure and chemical fertilizer have a positive effect on soil organic carbon(SOC).The increase of B treatment compared with CK treatment ranged from 31.76% to 35.34%.Compared with NPK,NPKB,NPKS,NPKSB,NPKM,and NPKMB all significantly increased SOC content.Among them,the best effect was NPKMB treatment.Compared with the treatments(CK,NPK,NPKS,and NPKM),applying biochar(B,NPKB,NPKSB,and NPKMB)significantly increased soil organic carbon(SOC)content.In addition,there was a very significant positive correlation between soil organic carbon components and SOC,and the treatment with highest correlation coefficient was the content of soil recombination organic carbon(HFOC)with a coefficient of 0.979**.2 Single biochar and simultaneous application of biochar with crop straw,organic manure and chemical fertilizer also have a certain impact on crop yield.The effect of single biochar has no effect on crop yield.Compared with NPK treatment,NPKB,NPKS,NPKSB,NPKM,and NPKMB have significantly increased the yield of crops by 1.79% to 17.66% Among them,the best is NPKMB treatment.The application of biochar on the basis of NPK treatment(NPKB),corn production increased significantly in 2015 and 2017,while in 2016,wheat production increased significantly,with an increase of 6.19%-12.2%.At the same time,the organic carbon component and the crop yield were extremely significantly positively correlated.The treatment with highest correlation coefficient was soil microbial carbon(MBC).3 Single biochar and simultaneous application of biochar with crop straw,organic manure and chemical fertilizer have positive effects on different forms of active organic carbon components.Compared with CK treatment,B treatment resulted in a significant increase in soil organic carbon content of 18.65%-32.80%.Compared with NPK treatment,NPKB treatment significantly increased the light fraction organic carbon(LFOC)and soil MBC content,while compared with NPKS and NPKM treatments,NPKSB and NPKMB treatments significantly increased soil water-soluble organic carbon(WSOC)content.Compared with CK treatment,NPKMB treatment has the most significant effect on the improvement of soil active organic carbon.At the same time,Test indexes sensitive to fertilization include the Labile organic carbon(LOC),water-soluble organic carbon(WSOC)and microbial biomass carbon(MBC),and the best indicator of soil organic carbon is soil LOC.In addition,there was a very significant positive correlation between organic carbon components and aggregate R0.25 values.The treatment with highest correlation coefficient was soil WSOC,and the correlation coefficient was 0.827**.4 Single biochar and simultaneous application of biochar with crop straw,organic manure and chemical fertilizer also have influence on organic carbon in soil particles.Compared with CK treatment,NPKMB treatment has the best effect on the increase of soil organic carbon.Sand-organic carbon content of B treatment increased significantly by 42.86%,compared with CK treatment.Compared with NPKM,the treatment with increased biochar(NPKMB)significantly increased soil organic carbon content.5 Single biochar and simultaneous application of biochar with crop straw,organic manure and chemical fertilizer have positive effects on the percent of soil macro-aggregates and the stability of agglomerates.Compared with the treatment of biomass carbon(CK,NPK,NPKM),the biochar application(B,NPKB,NPKMB)increased the percentage content of >0.25 mm particle size aggregates,which can promotes agglomeration of small-size aggregates to form large-size agglomerates.Compared with CK treatment,the best formation effect for >0.25 mm particle size aggregates are NPKS and NPKSB treatment.In addition,B and NPKB treatments can significantly increase the MWD,GMD and R0.25 values of aggregates compared with CK and NPK treatments.On the basis of NPKM,the application of biomass carbon(NPKMB)treatment also significantly increased the GMD value of aggregates.Compared with the CK treatment,the best effect for improving the stability of the aggregates is NPKMB treatment.6 Single biochar and simultaneous application of biochar with crop straw,organic manure and chemical fertilizer have a positive impact on the concentration of organic carbon in soil aggregates and the contribution rate of organic carbon.Compared with CK and NPK treatments,B and NPKB treatments can significantly increase the concentration of organic carbon in aggregates with a size of >0.5 mm.On the basis of NPKM,increasing the application of biochar(NPKMB)can increase the concentration of organic carbon in the 0.5-0.25 mm size aggregates.Among them,compared with CK treatment,the best effect of enhancing the concentration of organic carbon in large aggregates is NPKMB treatment.Compared with CK treatment,both B and NPK treatment can significantly reduce the contribution rate of <0.053 mm grain-size aggregate organic carbon with the largest decrease of 54.46%.Compared with NPK,both NPKM and NPKS significantly increased the contribution of >1 mm particle size aggregate organic carbon.Among them,compared with CK treatment,the best effect is NPKS treatment.Above all,single biochar,biochar with crop straw and organic manure have positive effects on the improvement and fertilization of yellow cinnamon soil,increasing soil organic carbon content and fractions of organic carbon content,promote the soil aggregate to a higher grade gathering,increasing content of the organic aggregate carbon,and improve the soil structure of yellow cinnamon soil,promote high yield and stable yield.