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我国北方土石山区的地形特点是土层薄、坡长坡陡、波状起伏、以坡耕地水土流失为主。该区水土流失严重,侵蚀沟道密集,对当地和下游造成严重的水土流失问题。为解决波状坡耕地水土流失的治理问题,针对波状坡耕地形态特征和水土流失特点,设计波状坡耕地拦挡淀排技术,并将其布设于野外径流小区进行观测。结果表明:1)拦挡淀排技术对波状坡耕地削流和减蚀作用均有较好的效果,2年平均的削流率和减蚀率分别为53.72%和87.21%,该技术对于各种类型的降雨均有较好的坡面削流效果,该措施的排水系统表现出可靠性和稳定性。2)通过对不同类型的降雨造成的径流量分析,拦挡淀排技术对波状坡耕地的径流调控率在降雨强度较大的情况下能发挥出较好的效果。通过趋势线分析,对照小区的产沙量与降雨量间的直线斜率大于措施小区(趋势线接近水平),说明拦挡淀排措施下不同降雨量产生的泥沙量都很小,拦挡淀排技术减沙效果显著。3)通过对次降雨资料分析表明,措施小区泥沙侵蚀量均远小于对照小区。波状坡耕地的年泥沙侵蚀量主要是由几场大暴雨引起的,拦挡淀排技术在大暴雨情况下也有显著的减蚀效果。通过添加趋势线分析发现措施小区泥沙侵蚀量与降雨量,降雨强度和I30之间均没有良好的线性关系,措施小区泥沙侵蚀量受降雨量,降雨强度和I30的共同影响。在雨季,措施小区泥沙侵蚀量受地表粗糙度的影响较大。4)从农作物产量来看,相同施肥条件下,拦挡淀排技术在干旱年比平水年份对作物增产的作用更明显。因此,拦挡淀排技术能够有效防治波状坡耕地水土流失,可作为一项新型坡耕地水土流失防治技术。
The terrain characteristics of the mountainous areas in the northern part of China are that the soil layer is thin, the slope is long and steep, undulating, and the main soil and water loss is on the sloping farmland. The soil erosion in this area is serious, with intensive erosion channels and serious soil and water loss problems both locally and downstream. In order to solve the problem of soil and water erosion in the wavy sloping arable land, aiming at the characteristics of the arable land and its characteristics of soil and water erosion, the technology of stopping the stubble in the arable slope was designed and placed in the field of runoff in the wild for observation. The results showed that: (1) The technology of barred stubble had a good effect on the creek cutting and erosion reduction. The average cutting rate and erosion reduction rate in two years were 53.72% and 87.21% respectively. The type of rainfall has a better slope cutting effect, the measures of the drainage system shows the reliability and stability. 2) Based on the analysis of runoff caused by different types of rainfall, the runoff control technology of barrage technology can exert good effect on the runoff regulation rate of arable land under the condition of heavy rainfall intensity. Through the trend line analysis, the slope of the straight line between the sediment yield and rainfall in the control plot is larger than that in the measure plot (the trend line is near the horizontal line), indicating that the amount of sediment produced by different rainfalls is very small, Sediment effect is significant. 3) Through the analysis of sub-rainfall data shows that the amount of sediment erosion in residential areas are much smaller than the control plot. The amount of annual sediment erosion in the wavy arable land is mainly caused by several heavy rainstorms. The technology of blocking the stubble drainage also has a significant effect of reducing erosion under heavy rainfall. By adding the trend line analysis, it is found that there is no good linear relationship between the amount of sediment erosion and the rainfall, rainfall intensity and I30 in the measures plot. The sediment erosion of the plot is affected by the rainfall, rainfall intensity and I30. In rainy season, the amount of sediment erosion in residential area is greatly affected by the roughness of the ground surface. 4) From the perspective of crop yield, under the same fertilization conditions, the effect of barging-stubbing technology on crop yield during drought years is more obvious than that of plain water years. Therefore, blocking the sediment technology can effectively prevent and control the water and soil erosion in the wavy sloping arable land, and can be used as a new prevention and control technology of soil and water loss on sloping farmland.