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运用RS与GIS技术,结合统计学方法研究了渭干河流域土壤盐渍化分布状况、表层土壤(0 cm-30 cm)盐渍化特征及其驱动力。结果表明:①流域盐渍化耕地总面积11.48×104 km2,占总耕地面积的39.83%。土壤盐渍化现象普遍,主要分布在绿洲的下部边缘地带,河流中下游、地势平缓低洼等区域。盐渍化土壤呈条形状分布,在绿洲边缘带呈片状分布,边缘的重度盐渍化土壤交错分布在轻度和中度盐渍化土壤中。②流域土壤pH值平均值为8.42,属于碱性土壤。土壤含盐量较高,平均值达到19.28g/kg,土壤盐渍化类型主要以硫酸盐和氯化盐为主。③渭干河流域土壤盐渍化是自然因素和人为因素相结合的产物,自然因素是形成条件,人为因素则促进了盐渍化的发展。
The distribution of soil salinization and the salinization characteristics of the topsoil (0 cm-30 cm) and its driving forces were studied using RS and GIS techniques combined with statistical methods. The results showed that: (1) The salinized cultivated land in the basin is 11.48 × 104 km2, accounting for 39.83% of the total cultivated land. Soil salinization is widespread and mainly distributed in the lower margin of the oasis, the middle and lower reaches of the river, and the gentle low-lying terrain. The salinized soil is in the shape of a bar, distributed in the form of flakes in the marginal zone of the oasis, and the heavily salinized soils in the margin are distributed in the mild and moderate saline soil. ② The mean value of soil pH in the watershed is 8.42, belonging to alkaline soil. Soil salt content is higher, the average value reached 19.28g / kg, soil salinization types are mainly sulfate and chloride. ③ Soil salinization in Weigan River Basin is a combination of natural and man-made factors. Natural factors are the formation conditions and human factors promote the development of salinization.