1:500000数字地理底图数据库的建立与应用

数字地理底图具备地图数学基础和基本地理要素(水系、居民地、交通、行政区界、地形等)，它是用作专题地图数据库或专题地图产品的骨架和控制的统一地理基础的数字地图。其主要作用是为专业部门建立专题数据库、编制各种专题图提供基本的数学基础、自然要素和人文要素，用于专题信息的定位，表现其与周围地理环境的关系和分布规律。是为满足各专业部门对地理信息数据的需求而开发的制作周期短、针对性强、信息量适中、易于使用、能够快速提供的数字地图产品。是对多尺度、多种类基础地理信息数据产品的补充。

Establishment and Application of the 1:500000 Digital Base-Map Database

Digital base-map with the map mathematical foundation and basic geographic elements (river system,inhabitant areas, transportation,boundaries,topography,etc.)can be used in the thematic map database of for the framework and control of some thematic map products. Its principal role is to provide basic mathematial base,natural elements and human elements for establishing varius thematic database and compiling various thematic maps, so as to locat the thematic information and prsent the relations and distributed law with the environment.Digital base-map are deveolped for the various special industrys' need.These industries require such digital map products with the following features:short period of production,strongly aiming at,moderate information volume,easy to use, and quickly providing.The digital base-map are a supplement to the multi-scale,multi-category basic geo-information products.