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一、盐碱土的地理分布成因榆林地区位于陕北黄土高原的北端,毛鸟素沙漠的南缘,盐碱土主要分布在本区长城沿线以北的风沙滩地区及无定河中上游河流两岸,据统计,全区重盐碱土达31.72万亩,多为低产的盐荒地。按盐碱土分布区的水文地理特征,可分为西部定、靖内流区湖盆滩地;东部横、榆、神外流区丘间滩地;无定河中上游河流阶地三大不同类型分布区(图1)。
First, the geographical distribution of saline-alkali causes Yulin region is located in the northern tip of northern Shaanxi Loess Plateau, the southern margin of the molluscan desert, saline-alkali soil is located in the area along the Great Wall along the north of the windy beach area and the middle and upper reaches of the Wuding River, according to Statistics, the region reached 317200 acres of salt and alkali soil, mostly low-yielding salt wasteland. According to the hydrological characteristics of the saline-alkali soil distribution area, it can be divided into the lakeside beach in the western Dingjing and Jing-yi rivers, the inter-mound beachland in the east, the elm and the Shen-outflow areas, and the three different types of distribution in the middle and upper reaches of the Wudinghe 1).