| The wind erosion of farmland in Bashang,Hebei Province is serious.Conservation tillage is one of the effective measures to curb farmland wind erosion.In recent years,no-tillage in autumn and late ploughing in spring has been promoted and achieved certain results.However,due to the inconclusive effect on wind erosion prevention,water retention and fertilizer retention,there are certain difficulties in popularization and application.Therefore,taking Kangbao County,Bashang District as a typical area,the differences in topsoil properties are compared through field sampling,taking no-tillage in autumn and late ploughing in spring as references.The effect of no-tillage in autumn and late ploughing in spring on wind erosion as well as its impact on soil fertilizer and moisture were studied in the paper.The results revealed as follow:(1)According to grain composition contrast,the average soil loss of no-tillage in autumn and late ploughing in spring is significantly lower than that of tillage farmland and early spring cultivated land,which were 26.77% and 63.26% respectively.The comparative study on sediment transport and wind erosion deposition also confirmed that no-tillage in autumn and late ploughing in spring can effectively inhibit farmland wind erosion,and hold topsoil.(2)The average soil moisture content of the cultivated layer of tillage farmland and early spring cultivated land is 8.16%.Correspondingly,average soil moisture content of tillage farmland is 7.22% and that of early spring cultivated land is 7.24%.The average soil moisture content of no-tillage in autumn and late ploughing in spring increase 13.2% and 11.55% respectively.Especially in the 0-10 cm soil layer,the water content of no-tillage in autumn and late ploughing in spring is 33.04% higher than that of tillage farmland and 19.61% higher than that of early spring cultivated land,indicating a protective effect on moisture.(3)After wind erosion,the average content of sand with no-tillage in autumn and late ploughing in spring decreased by 0.86% and the content of dry aggregate particles with diameter <0.85 mm in surface soil decreased slightly.Correspondingly,the average content of sand with no-tillage increased by 0.95%.The content of dry aggregate particles with diameter <0.85 mm decreased by 3.24%.The average content of sand with early spring cultivated land increased by 0.24% and the content of dry aggregate particles with diameter <0.85 mm decreased by 2.36%.The result showed that conservation tillage is effective in soil conservation.(4)After wind erosion,the contents of organic matter,total nitrogen,total phosphorus and total potassium in the surface soil of no-tillage in autumn and late ploughing in spring increased by 5.63%,1.14%,0.68% and 0.99% respectively.Correspondingly,the surface soil of tillage farmland decreased by 3.32%,1.61%,4.38% and 0.12% respectively.The surface soil of early spring cultivated land decreased by 0.52%,0.21% and 0.90%,but total potassium increased by 1.89%respectively.The results show that conservation tillage is effective in fertilizer conservation.In short,this paper uses extensive experimental data to confirm that compared with the traditional tillage and early spring cultivated land,the implementation of no-tillage in autumn and late ploughing in spring is effective in topsoil,water and fertilizer conservation. |
