DATABASE TRANSFORMATION, CADASTRE AUTOMATIC DATA PROCESSING IN QGIS AND IMPLEMENTATION IN WEB GIS
Keywords: Standard land values, Cadastre land register, Semi-automatic Mapping, QGIS, PostgreSQL, Python, Web GIS
Abstract. On the judicial basis of § 196 Baugesetzbuch (BauGB, 2018) every municipality in the Federal Republic of Germany must publish standard land values in €/m2 for its whole district area in a biennial cycle. The standard land values have to be derived comprehensively for different land use categories within this district. With the help of Geographic Information Systems (GIS) all the necessary data for the derivation of the standard land values can be analyzed. This data consists of cadastral information (ALKIS) (AdV, 2008) for each municipality district like streets, buildings, land parcels, areas of application for special building law as well as geocoded data about purchasing prices within the district’s real estate transactions. The following work contributes to both requirements, the statutory determination of the standard land values answering the legal necessity and the setting up of the generated geo data in the Web according to the transparency demanded by the European INSPIRE (Infrastructure for Spatial Information in Europe) directive. This report describes the implementation of the automated process of the setup of the relevant data layers based on ALKIS data in an Open Source GIS (QGIS) using SQL and Python scripts. The standard land values are visualized and presented in a Web GIS. After the evaluation of different alternatives, QGIS Server and Lizmap, an Open Source QGIS Web Client, were used for the web based presentation and accordingly configured.