| Owing to the problems involved in water resources, agriculture, environment and so on, the study on the transport of water and solute in soil is always pay attention to. In addition, considering the fact that most soil profiles assume layered structure in the field and that most bare soils are exposed to the atmosphere when salt accumulation in the surface soil is very rapid in spring, a laboratory investigation was conducted for capillary water rise in, and evaporation from different sand-layered soil columns under different atmospheric evaporation powers in the presence of shallow water table. The groundwater fluid was mineral water containing 3g/l NaCl. The effect of the thickness, the position, the particle size and its distribution of the sand layer on transport of water and salt and the estimated method of evaporation rate were studied, its mechanism was further examined. And the theory evaporation rate was calculated and its results were discussed. The main results are as follows:1. The results showed that there was linear function relationship between the capillary water rise velocity and the capillary water supply rate for the uniform soil and an non-linear power function relationship between them and the time, Green-Ampt model can be applied in simulating capillary water movement for the uniform soil in the presence of the shallow water table.2. The sand-layered soil had an important effect on the upward capillary water movement compared to the uniform soil column. The movement can be not only restrained but speeded as well. This is mainly related to the relationship of the hydraulic conductivity of the two soils in the profile i.e. whose conductivity will be larger. In the paper, the rate of the capillary water rise were limited by the sand layer when the distance between the low boundary of the sand layer and the water table ismore than 5cm, and the effect was intensified not only by the thicker sand layer and the higher sand layer position, but also by the worse sand particle size distribution. The change of the capillary water rise velocity and the capillary water supply rate for the layered soil were behaved by the relative position (i. e. the ratio of the position to the buried depth of water table), the effective particle diameter (i. e. D10, particle diameter with 10%) and the no uniform coefficient (i. e. , the ratio of the particle diameter with 60 % to the particle diameter with 10%) respectively.3. Whether the maximum height of the capillary water rise and water content of each layer soil for layered soil were changed or not were mainly determined by the sand soil texture, position, thickness, and their mutual relationship, and they also were closer connected with other soil texture in the profile. When the soil profile was certain, they will decrease when the sand layer meets with the conditions, i.e. 4. As far as evaporation from the high-salt soil with 50cm depth of water table was concerned, the evaporation rate remained steady with less than the 15d evaporation duration, and tended to be no steady with more than 15d duration under different atmospheric evaporation power, this was related to the formation of salt crust which in turn restricted water evaporation.5. The calculated steady rates by the empirical equation presented by Averiyanov had a large difference with the measured ones, and the calculated ones by the equation proposed by Lei et al (1988) had a well agree with the measured data, but the low limited value of the coefficient P for later equation needed further modify. In addition, the equation proposed by Lei et al was also proved to be suitable for calculating the no steady phreatic evaporation rate when coefficient was less than the stated value.6. The phreatic evaporation rate, the accumulative salt amount and salt concentration in the topsoil from the layered soils were smaller significantly than that from uniform soils except for the treatment whose distance of the sand layer to the water table was 0, this was...
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