The Map Symbol Base System is not only one of the basic functions of Geographic Information System, but also an important research issue in GIS.

地图符号库系统不仅是地理信息系统中不可缺少的基础功能模块之一，也是GIS的一个重要研究课题。

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This is the best map now available on this issue, but we are updating it constantly.

NPR: Oil Slick Threatens Lebanese Coast