坡度及作物种类对红壤坡耕地水土流失的影响研究

Study on the Effects of Slope and Crop Species on Soil Erosion in Red Soil Slope Farmland

坡耕地水土流失会导致作物产量及土壤生产力下降,坡度及作物种类是其主要影响因素之一,针对不同坡度及作物种类开展水土流失量对比研究,对于南方红壤区合理利用土地及水土流失防治措施具有指导意义。在5°、10°、15°坡地种植大豆、木薯、玉米等作物,开展了连续4 a的降雨侵蚀观测。2016-2019年的观测数据表明:作物种植类型对坡面径流量和土壤流失量影响显著,在自然降雨情况下,同一坡度的坡面,大豆种植的产流量及产沙量明显小于时蔬,并且大豆种植不仅是在种植当年能有效减少水土流失,在种植两年大豆之后再在同一坡面种植时蔬的单位面积土壤流失量要比一直种植时蔬的坡面小0.6 t/hm2,花生与木薯间作能降低年径流量与径流侵蚀量,是同坡度条件下的三分之二,在间作种植木薯与花生的情况下15°的坡面产流与产沙要明显小于10°的坡面,说明大豆种植及花生木薯间作更有利于南方红壤地区的水土保持治理,15°的坡面更利于种植经济作物。

Soil and water erosion in sloped farmland will lead to the decline of crop yield and soil productivity.Slope and crop species are one of the main influencing factors.The comparative study of soil and water erosion in different slope and crop species is of guiding significance for the rational use of land and soil and water erosion prevention and control measures in southern red soil area.Four consecutive years of rainfall erosion observation were carried out on 5°,10°and 15°slopes with soybean,cassava,corn and other crops.The observation data from 2016 to 2019 showed that crop species had a significant impact on slope runoff and soil erosion.When the slope is the same,the runoff and sediment yield of soybean planting were significantly lower than vegetables under natural rainfall condition.Soybean planting not only can effectively reduce soil erosion in the year of planting,but also resulted in 0.6 t/hm2 less soil loss per unit area two years after soybean planting compared to vegetable crops on the same slope..And peanut and cassava intercropping can reduce the annual runoff and runoff erosion,which is two-thirds of the same slope conditions.Under the condition of intercropping cassava and peanut,the runoff and sediment yield of 15°slope was significantly less than that of 10°slope.It shows that soybean planting and peanut cassava intercropping are more conducive to soil and water conservation in southern red soil area,and 15°slope is more conducive to planting economic crops.