Geodaten und Metadaten/en
Spatial data and metadata
According to art. 3(2) of Directive 2007/2/EG (INSPIRE Directive), spatial data is defined as "any data with a direct or indirect reference to a specific location or geographical area". Spatial data therefore describes an object in a landscape, either directly (using coordinates) or indirectly (using e.g. postcodes), or by the object’s spatial position. Spatial data can be interlinked by its spatial relationships, so as to facilitate the creation of detailed queries and analyses.
Spatial data can be further subdivided into geographic reference data and thematic geographic data
1. Geographic reference data can be understood as meaning data relating to map features such as landscapes and properties, typically provided by land registries and surveys. On the Portal, geographic reference data records comprise existing data from ALK, ALB and ATKIS, as well as DGM (previously managed separately) and scanned topographical map resources. Geographic reference data also links to reference systems, and the control networks and administrative boundaries used at a national, regional and local (e.g. plot) level. In the future, geographic reference data will also include image data such as orthophotos and aerial/satellite photos. Geographic reference data provides the basic information needed for the spatial mapping of thematic geographic data.
2. Thematic geographic data consists of the spatially referenced data collected in specific fields. Pursuant to the relevant legislation (regarding e.g. statistics, soils, conservation, etc.), thematic geographic data is managed in state- and federal-level administrations. Thematic geographic data can be presented as layers ‘on top’ of geographic reference data.
Alongside spatial data, metadata also forms an integral part of a spatial data infrastructure, and is essential when searching for, categorising, managing and archiving spatial data. Metadata, which essentially consists of ‘data about data’, provides users with a structured description of the underlying spatial data and spatial information services. Metadata describes spatial data in terms of its content, such as factual data, attributes, format, coverage, quality, spatial references and distribution. The informational content of metadata can be put to several uses, including the avoidance of redundant data collection, the discovery of existing gaps in datasets, the standardisation of data and terminology, dataset quality assurance, comparisons between alternative datasets and the creation of transparency in the spatial data market.
