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沙坡头地区降水是水份的主要补给来源,占补给总量的98.3％;凝结水仅对一年生短命植物有作用,无明显实际意义,尤其对灌木和半灌木。沙地蒸发散量是主要的消耗项,其占年降水的89.7—112.8％,有负亏缺现象,特别是固沙年代较长地区,人工防护体系发生变化和演替,水分不足是主要原因。热量变化是沙地水分运动的主要动力条件,容积热容量、导热系数、热扩散量是沙地热力学运动的基础参数,它与土壤水分和干容重相互制约,壤中热流和壤中水流耦合运动研究将进一步揭示水分运动规律的实质。
Precipitation in Shapotou is the main source of water supply, accounting for 98.3% of the total supply. Condensate has only an effect on one-year-old ephemeral plants, with no obvious practical significance, especially for shrubs and semi-shrubs. The evapotranspiration of sandy land is the main consumption item, accounting for 89.7-112.8% of the annual precipitation, which has the negative deficit. Especially in the longer area of the sand fixing, the change and succession of the artificial protective system are the main reasons. The change of heat is the main dynamic condition of water movement in sandy land. The volumetric heat capacity, thermal conductivity and thermal diffusivity are the basic parameters of the thermodynamics of sandy land. They interact with the soil moisture and dry weight, and the coupling of heat flow and soil water flow in the soil Will further reveal the essence of the law of water movement.