坡耕地垄作区田水土保持效益的研究

Study on Soil and Water Conservation Benefit of Contour Check in Sloping Field

黑龙江省的耕地约有５０％是坡耕地，在顺坡垄作改为横坡垄作以后，减轻了水土流失。但由于微地形的起伏变化，垄向仍然存在着一定的坡度，遇较大降雨仍能产生较强的水土流失。为此，探索一条防治坡耕地水土流失更为有效的途径是发展农业生产，改善生态环境的迫切需要。该文采用天然降雨和人工降雨方法对本课题组由数学模型所确定的最佳土挡间距进行了充分验征。结果表明：大豆增产１４．５％～２２．８％，玉米增产１６．２％～１９．７％，径流量减少８５％～１００％，冲刷量减少９０％～１００％，径流发生时间延长１５～１７倍。

The sloping fields account for about 50%of total fields in Heilong jiang province. Afterdownslope tillage changed into contour tillage,soil and water loss were alleviated,but because ofthe changes of small topography,direction of ridges still exist certain slope degree,however it meetheavy rain,serious soil and water loss can be produced.In order to prevent soil and water loss ofsloping field,develop agricultural production and improve ecological environment,this paper havefully testified the best ridge distance of contour check determined by mathematic model,which havebeen set tip by means of the method of natural rainfall and artificial simulated rainfall. The resultsindicated the contour check increased soybean yield by 14.5%～22.8%,increased maize yield by16.2%～19.2%,reduced runoff volume by 85%～100%,reduced erosion amount by 90%～100%,runoff producing time of the ridge tillage is 16～18 times as much as contrast.