Popis: |
To clarify the effects of alternation of drying and wetting on the formation of soil preferential flow in arid valley, taking the wasteland in the arid valley of Honghe River as the research object, we analyzed the soil preferential flow characteristics before and after the simulation of drying and wetting alternation based on dyeing tracer method, water breakthrough curve, and image processing technology. The results showed that, under the simulated alternation of drying and wetting, the matrix flow occurred in the 0-10 cm soil layer, the dyeing depth reached 35 cm, the horizontal width of the preferred path was only 3-10 cm, and the dyeing area curve fluctuated little. Simulated alternation of drying and wetting led to significant increases in the steady effluent, macropores number, and macroporosity. In the 0-20 cm soil layer, the steady effluent after alternation of drying and wetting was about 0.27 cm为明确干旱河谷气候区干湿交替作用对土壤优先流形成的影响,本研究以红河干旱河谷区的荒草地为对象,通过模拟干湿交替的方法,基于染色示踪和水分穿透曲线试验并利用图像处理技术,对比分析模拟前后土壤优先流特征的差异性规律。结果表明: 模拟干湿交替条件下基质流发生区在0~10 cm土层,染色深度高达35 cm,其优先路径的水平宽度仅为3~10 cm,且染色面积曲线波动小。模拟干湿交替条件导致土壤稳定出流速率、大孔隙数量和大孔隙率明显增加,在0~20 cm土层,实施干湿交替后的土壤稳定出流速率较非干湿交替条件高约0.27 cm |