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Roland Pesch, University of Vechta (Germany)
Winfried Schröder, University of Vechta (Germany)
Arne Unruh, University of Applied Sciences (Germany)
Lutz Vetter, University of Applied Sciences (Germany)
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We designed and implemented a WebGIS to serve as a planning tool for marine monitoring activities in the North and the Baltic Sea. Such systems are appropriate vehicles for publishing and illustrating of research results, thereby enabling to engage the public in the importance of environmental issues. Furthermore, web-based geoin-formation systems may serve to accomplish legally obligated report duties and to support environmental monitoring activities. Our WebGIS is realised using Open-Source-software considering standards and specifications for interfaces and handling of geodata determined by the Open Geospatial Consortium (OGC) to ensure interoperability between Web Map and Feature services (WMS/WFS). The software compo-nents consist on the Apache HTTP-Server and the UMN Mapserver. The mapserver thereby allows inquiries and analyses on spatial data (raster and vector) as well as generating and visualising maps. The database management system used is Post-greSQL with the spatial extension PostGIS. The Mapbender of CCGIS is used as user interface and for administration of map services.
The geodata that is up to now integrated in the WebGIS-application were mostly col-lected within the framework of the MarGIS project which was part of the GEOTECHNOLOGIES research focus. Approximately 235000 sample point data on salinity, temperature, silicate, nitrate, and ammonium at the interface Water body / sediment, and on grain size ranges could be made available from different national and interna-tional projects and databases. This data was compiled and structured in a relational database management system and linked with biological data on e.g. fish catches. Further data that can be visualised and queried by the application consists of raster information on bathymetry and geochemical, biological and sedimentological charac-teristics of the sea floor of the North Sea. Most of this data had been derived geosta-tistically and was used to calculate benthic habitat maps that can be used as a spa-tial reference system for monitoring activities in the North Sea. The geodata can be visualised using interactive tools like zooming, panning or centering. Data attributes can be screened by spatial as well as by logical queries. Additional GIS functions like intersection and buffering tools are furthermore implemented. Together with statistical functionalities it is possible to interactively select measurement sites for a certain area, for instance a certain habitat type and to compute chosen statistical measures.
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