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对旱坡地水土保持的截流沟措施、横坡种植措施和植物篱措施进行效益研究,结果表明:在裸露耕地上,水土流失十分严重,地表径流达到4 044.4m3/hm2.a、土壤流失高达172.4 t/hm2.a,以此速率流失土壤,其耕层(15 cm)约在12年后,将被冲刷殆尽。截流沟措施与横坡种植措施相比,可减少地表径流702.6m3/hm2.a和土壤流失19.2 t/hm2.a;但其占地面积大,农作物产量低,收益小。植物篱种植措施与横坡种植相比可减少地表径流345.3m3/hm2.a;土壤流失21.0 t/hm2.a。虽然植物篱占据耕地面积,但并不影响农作物产量。植物篱种植下的耕层土壤的酸碱度和质地得到改善,土壤养分含量有所提高,土壤侵蚀速率远低于易风化土壤的成土速率,同时结合人工翻耕,每年平均以17.5 cm的速度形成梯坎,以1.1°的速度减缓坡度。该项措施最终可实现坡改梯的目的,实现旱坡地的可持续利用。
The results showed that the soil erosion on the bare land was very serious, the surface runoff reached 4044.4m3 / hm2.a, and the soil loss reached as high as 172.4 t / hm2.a, the soil is lost at this rate and the topsoil (15 cm) will be washed away after about 12 years. Closure ditch measures can reduce the surface runoff 702.6m3 / hm2.a and soil loss 19.2 t / hm2.a compared with the horizontal slope planting measures; however, it covers a large area with low yield and low profit. The hedgerow planting measures can reduce the surface runoff 345.3m3 / hm2.a and the soil loss 21.0 t / hm2.a compared with the horizontal slope planting. Although Hedgerow covers the area of arable land, it does not affect the crop yield. The soil pH and texture of the topsoil planted under hedgerows were improved, and the soil nutrient content was increased. The soil erosion rate was much lower than that of the easily weedy soil. At the same time, with the manual tillage, the average annual rate was 17.5 cm Trapezoid, 1.1 degrees to slow down the slope. This measure will ultimately achieve the purpose of slope upgrading to realize the sustainable use of dry land.