半干旱地区河滩宜林地立地条件研究

采用对应分析、回归分析方法对半干旱地区河滩宜林地土壤基本性质进行了研究．结果表明，河滩地土壤理化性质的差异主要表现为土壤质地的差异，有机质含量、ＣａＣＯ３含量、全盐量、田间持水量等与土壤机械组成中细粒级含量（尤其是＜０．００１ｍｍ、０．００１～０．００５ｍｍ两个粒级）呈正相关．半干旱地区河滩宜林地立地条件主导因子为地下水位、土壤质地和有效土层厚度．采用最优分割法对地下水位、有效土层厚度进行了分级．以主导因子分级组合法综合考虑当地具体情况，将河滩宜林地划分为２０个立地类型，并对其进行了多树种综合评价．

Soil conditions of forest fitting land along river banks in semiarid region.

Basic soil properties of forest fitting land along river banks in semiarid region were studied with correspondence and multiple regression analyses, which showed that soil physical and chemical properties were mainly affected by soil texture. The organic matter content, CaCO 3 content, conductivity and field water holding capacity were positively correlated with the content of medium and fine particles in soil mechanical composition. The dominant factors affecting forest growth were soil texture, underground water level, and available soil depth, and the last two factors were classified by means of optimal cutting method. In considering of the local specific conditions with the grading combination of the dominant factors, the forest fitting land along river banks was classified into 20 site types, and the site quality was comprehensively evaluated by multiple species.