Effects Of Different Farmland Management Methods On Soil Physico-chemical Properties And Yield In Dryland Of Loess Plateau

As important agronomic management practices,soil tillage and straw returning have important effects on soil bulk density,water storage capacity,and maize yield.Therefore,understanding the effects of cultivation and straw returning on soil physicochemical properties and crop yields of spring maize fields has important theoretical and practical significance for the sustainable development of maize production in the Loess Plateau,China.Designed in 2016,this study mainly analyzed the effects of tillage and straw returning methods on soil bulk density,porosity,water use efficiency,nutrients and their impact on crop production in order to seek the best farmland management measures.The experiment adopted a randomized block design with two-factor cracking zones.The main area was soil tillage practice(T),and four treatments were set up:no-tillage(T1);deep pine(T2),rotary tillage 3(T3),Tillage(T4).The sub area is straw returning amount:100%straw returning(S1)and 0%straw returning(S2).The results showed that:(1)With the increase of soil depth,the soil bulk density of 0-30 cm shows an increasing trend,while the total porosity and capillary porosity show a decreasing trend.(2)In the 0-30 cm section of the plough layer,the total porosity of the deep-sown and straw-returning treatments remained the largest.Soil moisture in straw returning mode,soil moisture content of no-tillage treatment before spring corn sowing in 20-180 cm soil layer was significantly higher than other tillage methods(P<0.05);no-tillage treatment soil moisture content tends to be higher and All soil layers tend to be stable.(3)Soil nutrients in the 0-40 cm soil layer showed a decreasing trend in available nutrients and total nutrient.By analyzing straw returning to soil,the profiles of total nitrogen,available nitrogen,quick-acting phosphorus,and available potassium in the soil treated with straw returning were all significantly higher than straw straws returned to field.The treatment of deep-sown and straw returning showed superiority in soil total nitrogen,available phosphorus and organic matter content.(4)The maize yield and water use efficiency showed that the yield and water use efficiency of deep-season maize under different tillage methods were significantly higher than those under other tillage methods.Under the interaction,the yield of deep-sown and straw-returning treatments and water use efficiency were the highest.