Historical Digital Basic Landscape Model NW

The Digital Basic Landscape Model (Base DLM) describes the landscape in the form of topographical objects and represents a presentation-neutral, object-based vector database. The national database of the base DLM is frozen at the end of a year and is historicalised as a timeline. These timelines complement the data set of the Historical Basic DLM.

Geobasis NRW has been providing the Historical Basic DLM since 1997 in the data formats Shape and Geopackage and since 2008 additionally in NAS format.

数字基础景观模型（Digital Basic Landscape Model，Base DLM）以地形对象为载体对景观进行刻画，属于一类与呈现方式无关、基于对象的矢量数据库。该模型的国家级数据库会于每年年末冻结，并以时间线形式完成历史归档，此类时间线可作为历史基础数字景观模型（Historical Basic DLM）的数据集补充内容。
北威州地理基础数据中心（Geobasis NRW）自1997年起，便以Shape和Geopackage两种数据格式对外提供历史基础数字景观模型（Historical Basic DLM）；自2008年起，新增NAS格式的供应支持。