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风蚀和水蚀是黄土高原风蚀水蚀交错区土壤侵蚀的主要方式,研究风水交错侵蚀对土壤颗粒的影响对于准确评价该区土壤质量及环境影响有重要意义.本文采用风洞与模拟降雨试验相结合的方法,分析了风水交错侵蚀条件下侵蚀泥沙颗粒变化特征.结果表明:在11、14 m·s-1风速的风蚀下,坡面表层(0~1 cm)土壤颗粒粗化.其中,细颗粒(<0.01 mm)减小9.8%~10.8%,粗颗粒(>0.05 mm)增加16.8%~20.8%.风蚀改变了坡面物理性状,进而影响了降雨侵蚀泥沙颗粒变化.相对于未风蚀,风蚀处理的侵蚀泥沙细颗粒增加2.7%~18.9%,粗颗粒降低3.7%~9.3%.风蚀处理后,在不同雨强、不同降雨历时下,侵蚀泥沙颗粒变化趋势不同.雨强60、80、100 mm·h-1时,侵蚀泥沙颗粒变化较大,而雨强150 mm·h-1、产流>15 min时,变化趋势减缓.
Wind erosion and water erosion are the main ways of soil erosion in the ecotone between wind and water erosion in the Loess Plateau, and it is of great significance to study the effect of alternating erosion of soil and water on the soil particles in order to accurately evaluate the soil quality and environmental impact in this area.By combining wind tunnel with simulated rainfall test, The results show that under the wind erosion of 11,14 m · s-1, the grain size of the surface layer (0 ~ 1 cm) is roughened, among which, fine The decrease of particle size (<0.01 mm) by 9.8% -10.8% and the increase of coarse particles (> 0.05 mm) by 16.8% -20.8%. Wind erosion changed the physical properties of slope and further affected the change of sediment particles under rainfall erosion. , The erosion of the erosion of fine sand particles increased by 2.7% to 18.9%, coarse particles decreased by 3.7% ~ 9.3% after wind erosion treatment, under different rainfall intensity, rainfall duration, erosion sediment particles change trend. , And 80,100 mm · h-1, the sediment particles changed greatly. However, when the rainfall intensity was 150 mm · h-1 and the flow rate was more than 15 min, the change tendency was slowed down.