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美国农业研究机构通过研究建立了能够描述山坡断面上土壤再分布的耕蚀预测模型 (TEP) ,并用此模型来解释坡耕地上耕作引起的土壤侵蚀和沉积模式 ,此模型以分散率为基础 ,其中表示土壤迁移和坡度关系的回归系数用分散系数k′来描述。利用已公布的有壁犁的k′值 ,计算了Minnesota中西部地区一个已测定好的地形断面上5 0a内土壤的再分布情况 ,另外还模拟总结出了二次耕作 (串连耙 )和坡段的检测长度对模型计算出的土壤再分布率的影响。结果表明 ,使用k′为 2 34kg/m的有壁犁耕作时 ,所测断面土壤侵蚀和沉积率大于 10t/ (hm2 ·a)的面积为 14 7% ,若k′为 3 30kg/m时 ,则侵蚀或沉积率大于 10t/ (hm2 ·a)的面积增加到 2 6 % ,另外的二次耕作 (串连耙 )将进一步使土壤再分布的面积增加到 5 9%。该模型能依据地形结构确定耕作引起的土壤再分布的面积
The US Agricultural Research Institute established a model of cropland erosion prediction (TEP) that can describe the redistribution of soil on hillsides and used it to explain soil erosion and deposition patterns caused by tillage on tillage. Based on the dispersion rate, The regression coefficient, which indicates the relationship between soil migration and slope, is described by the dispersion coefficient k ’. Based on the published k ’values for wall plows, redistribution of soil over a 50-aa section of a well-defined topography in the central and western Minnesota has been calculated. In addition, secondary tillage (tandem rake) and Influence of the detection length of slope section on the soil redistribution rate calculated by the model. The results showed that the area with soil plowing and sedimentation rate greater than 10t / (hm2 · a) was 14.7% when k ’was 2 34kg / m, and when k’ was 330kg / m , The area of erosion or deposition greater than 10t / (hm2 · a) increased to 26%. The additional secondary tillage (tandem rake) further increased the area of soil redistribution to 59%. The model determines the area of redistribution of soil due to tillage based on the topography