| The lime concrete black soil is mainly distributed in the south of huang-huai plain,which is one of the main low yield soil types in China.A major cause of the middle and low grain at lime concrete black soil area is that soil with montmorillonite in the main clay minerals are caused by a series of bad properties such as physics,chemistry,which obstacle factors performance that the texturethe of soil sticky and heavy,structural poor,drying shrinkage and wet bilg,easier to flood and drought,and tilth is poor,which lead to soil preparation sowing quality is difficult to improve.The agricultural production in this area has been inclined to apply chemical nitrogen fertilizer for a long time.And blind fertilization not only leads to the waste of fertilizer,but also limits the improvement of crop yield and quality for a long time.Moreover,the soil structure is damaged continuously,and the soil compaction is more serious,resulting in the decline of soil quality.Soil organic matter is not only the direct expression of soil fertility but also an important factor to comprehensively reflect soil quality.Therefore,sthdy condition of soil organic matter promotion in surface layer of lime concrete black soil with different tillage measures,and discusses the relationship of soil organic matter and soil and water conservation,which have important guiding significance for looking for best tillage measures improving the surface soil fertility and soil and water conservation in lime concrete black soil,improved agricultural production conditions,and provided productivity.of lime concrete black soil.This paper studyed physical and chemical properties such as infiltration capability aggregate characteristics by reviewing literature,field experiment and laboratory soil physical and chemical properties experiment.Six treatments were set: treatment 1: conventional straw return + biological activator + fertilizer;treatment 2: straw returning to field + chemical fertilizer;treatment 3: conventional straw return + biochar + fertilizer;treatment 4: no straw returned to the field + fertilizer;treatment 5: straw dislocation wheel + biological activator + fertilizer;treatment 6: straw shift wheel + fertilizer.Then this paper analyzed lime concrete black soil nutrient indicators such as soil organic matter under diffierent tillage measures in lime concrete black soil,probed into the difference of the soil infiltration capability under different cultivation measures in lime concrete black soil.The response of soil infiltration and aggregates to organic matter was studied by correlation analysis in lime concrete black soil.The main conclusions are as follows:(1)There were significant differences in soil organic matter in the surface layer(0-15 cm)of lime concrete black soil under different tillage measures,which the soil organic matter in the surface layer with biochar was significantly higher than that in other treatments(P<0.05).Compared with the control group(no straw returning to the field,no deep ploughing),conventional straw returning to the field + biochar soil organic matter significantly increased(P<0.05)during the same crop period,which was shown as follows: wheat jointing stage increased 26.46%,wheat maturity stage increased 46.01%,corn jointing stage increased 26.74%,corn maturity stage increased 26.83%.Compared with the control group,conventional straw mulching and conventional straw mulching + biological activator tillage measures had a small effect on the improvement of soil organic matter,about 2%,which indicated that conventional straw mulching had a small effect on the improvement of soil organic matter in the first year.Compared with the control group,the organic matter content in the topsoil decreased under the tillage measures of straws misaligned rotation in the first year(deep ploughing to 30 cm before wheat sowing).But,the soil organic matter content increased in the following year.(2)There was no significant difference in soil total nitrogen content in the surface layer of lime concrete black soil under different tillage measures,but the soil total nitrogen content in the surface layer with biochar was higher than that in other treatments.Compared with the control group(no straw returned to the field,no biochar added),the total nitrogen content in the soil of conventional straw returned to the field + biochar surface layer increased during the same period but not significantly.Compared with the conventional straw mulching,the total nitrogen content in the topsoil reated with misplaced straw mulching(treatment 5 and treatment 6)decreased.The contents of total phosphorus,total potassium,available phosphorus and available nitrogen in the surface layer between treatments showed no regular change.However,the available potassium content in the surface layer with biochar was significantly higher than that in other treatments(P<0.05).Compared with conventional straw mulching,the content of available potassium in the topsoil treated with misplaced straw mulching(treatment 5 and treatment 6)decreased.(3)The top layer of lime concrete black soil under different cultivation measures cumulative infiltration amount is shown as: straw returning regular + biochar > straw returning regular + biological excitation agent > straw returning regular + chemical fertilizer > straw dislocation + biological excitation agent > straw dislocation chakras also > straw returned,dislocation of straw + biological exciting agent and straw dislocation chakras also handles the top layer of the cumulative infiltration amount.This study showed that the soil infiltration performance of straw mulching combined with biochar tillage was the best,followed by straw mulching combined with bioactivator,but the improvement effect of soil infiltration performance was limited compared with that of straw mulching alone.The effect of soil infiltration was limited two years before the straw was returned to the field.(4)The top layer of lime concrete black soil under different cultivation measures of soil bulk density: no straw counters-field dislocation(1.24 g/cm3)> straw round(1.17 g/cm3)> straw dislocation wheel also + biological excitation agent(1.13 g/cm3)> straw returning regular(1.07 g/cm3)> straw returning regular + biological excitation agent(1.03 g/cm3)> straw returning regular + biochar(0.97 g/cm3)and its corresponding soil porosity is opposite.There was no regular change in the distribution characteristics of lime concrete black soil aggregates under different measures.Compared with the control group,after the application of biochar and straw mulching,the content of organic matter in the surface layer of black soil increased,the soil aggregate structure increased,the bulk density decreased,and the porosity increased.After the wheat was sown deep(up to 30cm),the deep soil turned to the surface,resulting in an increase in surface soil bulk density and a decrease in porosity.When the surface soil turns down to the deep layer,the bulk density of the deep soil become decrease and porosity become increase.Biological activator had a poor effect on the surface soil bulk density and porosity.(5)The cumulative infiltration amount and infiltration rate of the surface soil of lime concrete black soil increased with the increase of organic matter content,decreased with the increase of soil bulk density,and increased with the increase of soil porosity.Moreover,the cumulative infiltration amount of soil with biochar and straw returned to the field was the largest.Under different tillage measures,soil organic matter decreased with the increase of soil bulk density,and the soil porosity was the largest when biochar and straw were added to the soil.However,under different measures,there was no obvious regularity between the change characteristics of soil aggregates and the content of organic matter,which might be related to the characteristic of "dry compaction,wet and muddy" in the lime concrete black soil. 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