Study On Protective Tillage Measures In Maoshan Watershed Of Zhalaite County Inner Mongolia

With the development of society and the increase of population,the exploitation of natural resources by human beings has become more and more fierce.As a result of unreasonable utilization and management,the ecological and environmental conditions tend to deteriorate.Soil erosion is an ecological problem worthy of our attention.In this paper,Maoshan watershed is selected as the research object,assisted by GIS technology.Combined with land resource survey and soil nutrient spatial analysis for the purpose of agricultural utilization of land capacity evaluation,and protective cultivated land measures in the Maoshan watershed were further studied.It provides theoretical basis and technical support for protecting effective farmland and reducing soil erosion.Combining relevant data and applying scientific and reasonable theoretical analysis methods,the following conclusions are obtained:(1)The soil nutrient distribution in Maoshan watershed conforms to normal distribution,and the variation coefficients of soil organic matter,alkali-hydrolyzed nitrogen,available phosphorus and available potassium were 17.34%-40.81%.The soil nutrient spatial distribution generally increased from northwest to southeast,and the content in the middle of the basin was higher than that in the east and west sides.(2)The results of land capacity evaluation in Maoshan watershed are divided into six grades:Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ and VI,which account for 10.67%,30.04%,33.41%,9.42%,10.99%and 5.38%respectively.(3)Under the same rainfall conditions,cross-slope tillage,bamboo-ridge I and bamboo-ridge II have different effects on reducing runoff and sediment compared with downslope tillage,and bamboo ridge Ⅱ has the most significant effect.The bamboo ridge Ⅱwork best,the initial time of runoff was prolonged by 38min and the reduction rates of runoff and sediment were 57.1%and 51.9%respectively but soil organic matter,nitrogen,phosphorus and potassium in 0～20cm soil average content were increased by 5.89%,11.48%,16.54%,21.75%compared to cross-slope tillage.(4)The average content of soil organic matter,available phosphorus and available potassium increased with the increase of organic fertilizer,except for alkali-hydrolyzed nitrogen.(5)The hedgerow on the ridge has obvious water and soil conservation benefits compared with the downslope and cross-slope tillage.The runoff is reduced by 81.53%and 65.71%,and the erosion is reduced by 74.89%and 54.26%.In terms of soil nutrients,hedgerows on ridges increased by 15.89%-36.05%and 3.64%-13.47%respectively compared with downslope tillage and cross-slope tillage.