在土壤普查中,不仅要查明土壤的类型、分布和生产特性,还要查明土地资源,并对土地资源进行评价,做为省、地、县、社进行农业区划、生产规划和因地制宜地发展农业生产的依据,以达到合理利用土地、充分发挥土地生产潜力,不断提高产量和土地肥力的目的。土地资源评价也称谓土地生产力分级,它是根据土壤肥力性状和它所处的生产环境条件(如地形、水文地质条件、气候等)对土地生产力的综合评价,既反映土地的生产潜力,也反映生产上的限制因素。国外应用较早,如美国在六十年代便制订了土地生产力分级系统,把全国土地分为八级。在英国将土地分为七级。我国在这方面的研究尚少,为了配合本 In soil census, not only to identify the type of soil, distribution and production characteristics, but also identify the land resources, land resources and evaluation, as the provinces, prefectures and counties, social farming division, production planning and local conditions Development of agricultural production basis in order to achieve the rational use of land, give full play to the potential of land production, and continuously improve the yield and land fertility purposes. Land resource assessment also refers to land productivity classification, which is a comprehensive evaluation of land productivity based on soil fertility traits and the production environment conditions (such as topography, hydrogeological conditions, climate etc.), which not only reflects the productive potential of land but also reflects Production constraints. Earlier foreign applications, such as the United States in the sixties have developed land productivity rating system, the country’s land is divided into eight levels. The land is divided into seven levels in the United Kingdom. Our country still has few studies in this area, in order to cooperate with this