The importance of georeference data credibility in spatial management with particular emphasis on the analysis of validity of data on land use in selected communes of the Mazovian Voivodeship

Abstract

Spatial data, constituting the basis of the planning process, are the key element of decision making and activities related to spatial management and development planning. They constitute the starting point for analyses and concepts, and further specification of assumptions for directions of development and management. They also directly affect quality of prepared planning documents. The origin and amount of data are important indicators of changes in the planning process – a large amount of available data does not determine their completeness and credibility.
Spatial management and spatial planning are interdisciplinary issues. Therefore, they require varied georeferenced data. The type of used data and their accuracy depend on the type and size of the analysed area, as well as on their intended purpose. The current development of IT technologies, and particularly GIS software, offers extensive possibilities of processing, analysis, and visualisation of data. However, it should be emphasised, that even the most advanced analyses will not provide accurate results, if input data are not credible. In the case of application of thematic data in the digital form, a diligently developed data base is of key importance. Accurately prepared data facilitate spatial planning process. Such data should be credible, complete, and ordered coherently throughout the country.
The primary legal document regulating the issue of obtaining, maintenance, and disclosure of spatial data is the act of 4 March 2010 on spatial information infrastructure. The document emphasizes the conditions of development and application of infrastructure for spatial information, facilitating among others the use of data through optimisation of their obtaining and maintenance. The spatial information infrastructure in Poland constitutes a part of the Spatial Information Infrastructure in the European Community, specified in the Directive of the European Parliament and of the Council, called the INSPIRE directive.
The objective of this paper is to determine the importance of reference data reliability for the purposes of planning documents. The paper justifies the necessity of providing an accurate level of reliability of data used for the purposes of spatial planning. The study was conducted in selected areas of the Mazovian Voivodship (communes Małkinia Górna, Zaręby Kościelne, Cegłów). It involved the use of basic cartographic materials, obtained for spatial management purposes. Selected reference data were analysed, with the main focus on rural areas and their management. The analysis concerned data related to cadastral parcels. The data in the cadastral map were compared with those in the land register, and the actual land use.
The results unequivocally suggest that registration of changes in land use is delayed. As a result, land use data in the land register are invalid in 1-12% of the area. This particularly concerns developed and wooded or forested land. Errors resulting from inaccurate description of land also occur. This particularly results from the order of data registration. In all areas covered by the study, land use was analysed based on cadastral data, an orthophoto map, and field research.
The study reveals that in spite of the increasing possibilities of access to varied data, ensuring their credibility still poses a challenge impeding the work of geodesists and planners. It can lead to taking wrong decisions with irreversible consequences.