Soils

This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The information was prepared by digitizing maps, by compiling information onto a planimetric correct base and digitizing, or by revising digitized maps using remotely sensed and other information.本数据集属于数字土壤调查成果，一般为美国国家合作土壤调查（National Cooperative Soil Survey）所编制的最精细级别的土壤地理数据。该数据集的制作方式包括：对地图进行数字化处理；将信息整合至经过平面校正的基底图层后开展数字化作业；或是借助遥感及其他相关信息对已数字化的地图进行修订完善。