Topic level
A topic level ( engl. Thematic layer) in a GIS is an illustration of a data source according to relevant logical aspects. she can
- as a raster or as a vector plane and
- is usually assigned to the basic data or the factual data .
Thematic levels correspond in many ways to the earlier thematic maps and are the basic principle of the level system . Typical groups of topic levels in the GIS of a federal state or in the communal information system of a larger municipality are e.g. B.
- Basic data
- digital cadastre , urban planning , administrative boundaries and
- the pipeline network (electricity, water, sewer, gas, oil),
- digital terrain model (DGM)
- Image archive (satellite and aerial images )
The first two groups are usually organized in vector form , while the data from the third and fourth groups are organized as rasters in different resolutions .
- Factual data
- Traffic and communication (various types of roads , motorway maintenance depots , railways , higher-level hiking trails, telephone network , transmission systems, etc.)
- Water network , groundwater areas , flood zones, avalanche and torrent control
- Geology (geological maps , profiles and boreholes, rock types , tectonics , deposits , bulk raw materials , geochemistry ...)
- Soil science (natural area structure, soil types , slope and exposure , erosion , test tree grid, etc.)
- Nature and spatial planning ( nature and water protection areas , EU target areas, building land borders , etc.)