Shaanxi Provincial Land Engineering Construction Group Co., Ltd, Xi'an, Shaanxi, 710075, China.
Institute of Land Engineering and Technology, Shaanxi Provincial Land Engineering Construction Group Co., Ltd., Xi'an, Shaanxi, 710075, China.
Sci Rep. 2019 Oct 11;9(1):14719. doi: 10.1038/s41598-019-51257-y.
The Mu Us sandy land in China's Shaanxi Province faces a critical water shortage, with its aeolian sandy soil endangering the regional eco-environment. Here we investigated the effects of feldspathic sandstone on water retention in an aeolian sandy soil from the Mu Us sandy land. Feldspathic sandstone and aeolian sandy soil samples were mixed at different mass ratios of 0:1 (control), 1:5 (T1), 1:2 (T2), and 1:1 (T3). Soil-water characteristic curves were determined over low- to medium-suction (1-1000 kPa) and high-suction (1000-140 000 kPa) ranges, by centrifuge and water vapor equilibrium methods, respectively. Results showed that the addition of feldspathic sandstone modified the loose structure of the aeolian sandy soil mainly consisting of sand grains. The van Genuchten model described well the soil-water characteristic curves of all four experimental soils (R-values > 0.97). Soil water content by treatment was ranked as T2 > T3 > T1 > control at the same low matric suction (1-5 kPa), but this shifted to T2 > T1 > T3 > control at the same medium- to high-suction (5-140 000 kPa). T2 soil had the largest saturated water content, with a relatively high water supply capacity. This soil (T2) also had the largest field capacity, total available water content, and permanent wilting coefficient, which were respectively 17.82%, 11.64%, and 23.11% higher than those of the control (P-values < 0.05). In conclusion, adding the feldspathic sandstone in an appropriate proportion (e.g., 33%) can considerably improve the water retention capacity of aeolian sandy soil in the study area.
中国陕西省毛乌素沙地面临严重的水资源短缺问题，其风成沙质土壤危及区域生态环境。本研究调查了来自毛乌素沙地的风成沙质土壤中长石砂岩对水分保持的影响。将长石砂岩和风沙土样品按质量比 0:1（对照）、1:5（T1）、1:2（T2）和 1:1（T3）混合。采用离心和水汽平衡法分别在低-中吸力（1-1000 kPa）和高吸力（1000-140000 kPa）范围内测定土壤水分特征曲线。结果表明，长石砂岩的添加主要改变了由砂粒组成的疏松风沙土结构。Van Genuchten 模型很好地描述了所有四种实验土壤的土壤水分特征曲线（R 值>0.97）。在相同的低基质吸力（1-5 kPa）下，各处理的土壤水分含量排序为 T2>T3>T1>对照，但在相同的中-高吸力（5-140000 kPa）下，排序变为 T2>T1>T3>对照。T2 土壤的饱和含水量最大，供水能力较强。该土壤（T2）的田间持水量、总可用水量和永久萎蔫系数也最大，分别比对照高 17.82%、11.64%和 23.11%（P 值<0.05）。总之，以适当的比例（例如 33%）添加长石砂岩可以显著提高研究区风成沙质土壤的保水能力。
