土壤盐渍化是影响农业生产与生态环境的一个重要因素。长期以来,宁夏银川平原的次生土壤盐渍化问题十分突出,形成了许多盐渍型中低产田,影响和制约了区域农业的可持续发展。主要采用遥感解译方法提取了银川平原土壤盐渍化的分类与分布的现状信息。在此基础上,依据中低产田的分类标准,将相关的耕地类型、土壤肥力、作物产量、灌排水指标等因子转化成数字化专题图层,采用多源信息复合分类的方法,通过“综合分析,主导因子判定”实现了GIS辅助下的中低产田分类,为遥感和地理信息系统技术在土壤盐渍化和中低产田调查研究中的应用,探索出了一条可行的途径。

The soil salinity is an important problem to agriculture production and ecological environment.The salinity has been a key factor to form a lot medium & low yield croplands and to affect the sustainable agriculture development in Yinchuan Plain(YCP),Northwest China.In the study,the suitable time for receiving the remote sensing data(TM) is selected.Based on the remote sensing data and the some soil investigation,the soil salinity has been extracted and their classification is made.It is found that the soil salinization degree and the total distribution area of soil salinity are being alleviated remarkably from 1985.With the support of the RS and GIS,the thematic information related to the formation of the medium & low yield croplands such as the types of farmland,soil salinity degree;fertility,crop yield etc.,are extracted and are put into the compound classification.Through this method,the present situation including their classification and distribution of the medium & low yield croplands in the area is determined clearly.Finally,some analyses on the causes of the soil salinity change in YCP are brought forward.