Experimental Study of the Soil Water Dissipation Law of Vegetated Slopes under Natural Evaporation Conditions

Under the combined action of soil evaporation and vegetation transpiration, the law of soil water dissipation at different depths of vegetated slopes is unknown and the related influencing factors are unclear. In this paper, six large-scale slope models were constructed for long-term dynamic monitoring of soil water. The effects of slope ratio and vegetation on the dynamic changes in soil water at different depths were analyzed. Pearson correlation analysis was used to analyze the relationship between slope conditions, meteorological factors, and soil water dissipation. The results show that under the condition of natural evaporation, slope ratio has little effect on the dynamic change in soil water in bare slopes. However, the greater the slope ratio of vegetated slopes, the faster the soil water decreases in the 40 cm depth range. Additionally, soil water dissipation follows a logarithmic functional relationship with evaporation time in both bare and vegetated slopes. The correlation between slope conditions and soil water dissipation is stronger than that of meteorological factors. The research results can provide some theoretical support for exploring the hydrological effects of vegetated slopes.