农业工程学报Issue(14)：115-123,9.DOI:10.3969/j.issn.1002-6819.2014.14.015
适量砒砂岩改良风沙土的吸水和保水特性
Improvement of water absorbing and holding capacities of sandy soil by appropriate amount of soft rock
摘要
Abstract
The contiguous areas of Shanxi, Shaanxi and Inner Mongolia in China are rich in mineral resources and serves as energy supply base. Desertification and soil-water losses are very serious problems in this area. Water is a main limiting factor of local ecological environment and the development of farming and animal husbandry. Soft rock is widely distributed in the area, which has strong water retention ability. Using soft rock to improve the sandy soil has a great potential, but little is known about the hydraulic properties of soft rock amended sandy soil. This study was conducted to understand the effect of different amount of soft rocks on water absorbing and holding capacities of sandy soil. In this paper, we measured the water infiltration, saturated hydraulic conductivity and soil water characteristic curves of soft rock and sandy soil mixtures. The various soil water characteristic curve models included in the RETC software was used to analyze the water absorbing and water holding properties of soft rock-sand soils mixtures. The objectives of this study were to evaluate the improvement of soft rock on the soil absorbing-holding water properties of sand soils, and to select optimal mixture ratio of the soft rock and sandy soil. The results showed that:1) Soft rock significantly decreased the water infiltration rate and saturated hydraulic conductivity, but increased the saturate water content and residual water content, and hence increased the capacity of sandy soil to retain water. The saturated water content and residual water content of sandy soil increased with the amount of soft rock added into sandy soil. For the treatment of 25%soft rock and 75% sandy soil mixtures, the amended sandy soil have the similar saturated water content and soil water characteristic curve as the loess soils. 2) The effects of soft rock on water absorbing and holding capacities of sandy soil were significantly influenced by bulk density. Water infiltration rate, saturated hydraulic conductivity and saturated water content decreased with the increasing of the bulk density in the same mixture pattern. With the increase of bulk density of the mixture, the volumetric water content decreased at the low soil water suction condition, but increased at the relatively higher soil water suction condition. 3) RETC software contains eight models, and every model can be used to fit the soil water characteristic curves of soft rock amended sandy soil. Among the eight models, VGM (m, n) was the best model with the largest R2 and F value. 4) Parameter of VGM (m, n) model is an empirical parameter, the smaller the parameter, the slower the soil water released. Fitting results in VGM (m, n) showed that the parameter of the soil with the 25%soft rock and 75%sandy soil was less than sandy soil and greater than soft rock. The results from this study suggested that the mixture of 25%soft rock and 75%sandy soil can significantly improve the water absorbing and holding capacities of sandy soil and this mixture pattern can be recommended in practice.关键词
土壤/水分/入渗/砒砂岩/风沙土/饱和导水率/土壤水分特征曲线Key words
soils/moisture/infiltration/soft rock/sandy soil/saturated hydraulic conductivity/soil water characteristic curve分类
农业科技引用本文复制引用
摄晓燕,张兴昌,魏孝荣..适量砒砂岩改良风沙土的吸水和保水特性[J].农业工程学报,2014,(14):115-123,9.基金项目
中国科学院西部行动计划（KZCX2-XB3-13-02）；教育部新世纪优秀人才支持计划 （）
