Study on the Variation Characteristics of Rising Capillary Water of Layered Soil under Variation of Sand Layer and Thickness北大核心CSCD

【Objective】The purpose of this paper is to solve secondary salinization of soil in Northwest China. 【Method】the capillary water rising movement characteristics of layered soil has been analyzed through indoor test. And the variation characteristics of capillary water movement under the influence of common change of layer and thickness of sand layer has been considered in this paper, and functional relationship between groundwater recharge and height of capillary water rising with time changing has been built. Furthermore, contour distribution of groundwater recharge and capillary water rising height has been also comparative analyzed.【Result】There was a very significant positive correlation between the horizon and the volume constant and the height constant （P<0.01）. And there was a significant negative correlation between the horizon and the stable recharge rate of groundwater and the rate of steady increase of capillary water （P<0.05）. There was a significant negative correlation between the thickness of sand layer and stable recharge rate and steady rising rate（P<0.05）. When the duration of the capillary water height was rising was 0~4 days, the sandy layer was 30~50 cm, the thickness of sand layer was 0~15 cm, which has a significant effect on the change of groundwater recharge and height of capillary water. When the duration of the capillary water height was rising was 4~12 days, the sand layer is distributed in 15~30 cm, the thickness of sand layer was 15~30 cm, which has a significant effect on the change of groundwater recharge and height of capillary water. To summarize, the results of this study were of great significance for the study of water salt movement and soil salinization in layered soils.【Conclusion】The fitting parameters of the function including volume constant (v), stable recharge rate (q*), groundwater recharge time constant (τQ), capillary water rising height (υ), steady rising rate (μ*) and rising height time constant (τh) were determined by the variation of capillary groundwater recharge and capillary water height with time changing respectively. © 2019 Journal of Irrigation and Drainage. All rights reserved.