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刺槐、柠条、沙棘、沙棘×油松、沙棘×小叶杨幼林到郁闭成林的蓄水保土效益变化分３个阶段。１～３年生为低下阶段，有侵蚀性降雨就会发生水土流失；４年生为由低到高的过渡阶段，蓄水保土效益迅速增加，５年生以上为效益显著阶段。一般在无大暴雨情况下基本不发生水土流失，且６０％的林分覆盖度对减少土壤侵蚀量的作用显著。各郁闭成林的枯落物蓄积量和容水量以沙棘及其混交林最多，刺槐林中等，柠条林最少。并且枯落物的厚度是增强土壤抗冲性效应的重要指标。同时森林改善了土壤物理性质，使土壤容重变小，入渗和抗冲性增强。
Robinia pseudoacacia, Caragana korshinskii, Seabuckthorn × Pinus tabulaeformis, Seabuckthorn × Populus × euphratica forest to Yu closed forest water and soil conservation benefits changes in three stages. 1 to 3 years of low stage, there will be soil erosion erosion erosion; 4-year-old from low to high transitional stage, water and soil conservation benefits increased rapidly, more than 5 years of age as a significant stage of efficiency. Generally, no soil erosion occurred under the condition of heavy rainstorm, and the effect of 60% coverage on reducing soil erosion was significant. The litter volume and water holding capacity of each canopy closed forest were the highest in seabuckthorn and mixed forest, the middle of acacia forest and the smallest in Caragana korshinskii. And the thickness of litter is an important index to enhance the soil anti-scourability effect. At the same time, the forest improved the physical properties of the soil, reduced the soil bulk density, and enhanced the infiltration and impact resistance.