An ecotope map of the trilateral Wadden Sea
Description
These data present the first digital, publicly available, ecotope map of the trilateral Wadden Sea covering the Netherlands, Germany and Denmark. This ecotope map, representative for the time period 2008-2012, was developed on the basis of bathymetry, salinity, flow velocity, exposure time, sediment composition, hard substrates and salt marshes. Ecotopes are discrete classes of the physical environment based on the distributions of communities in an ecosystem. An ecotope map can give a first–order estimate of the potential spatial distribution of species and communities. The use of a single, consistent and well-defined ecotope system makes it possible to compare the proportions of the different ecotopes and compare properties of the tidal basins over the entire trilateral Wadden Sea. This ecotope map of the trilateral Wadden Sea area followed the ecotope system for coastal waters ZES.1 typology that was developed in the Netherlands. This ecotope system is based on the notion that local physical environmental factors and processes are main determinants of communities. The main physical environmental factors and processes in the ZES.1 system were mean and variability of salinity, substratum type, mean water depth, and hydrodynamics. Class boundaries were used to classify the continuous variables in order to define the ecotopes. The ZES.1 ecotype system hierarchically arranges the ecotope variables on the basis of the dominance of the physical environmental factors and processes in determining community composition. Within the scale level of ecotopes, typical ecological communities with structuring characteristics may occur in smaller areas, deviating from the general ecological communities that are present elsewhere in the ecotope involved. These are called eco-elements. The occurrence of eco-elements depends partly on coincidental processes and partly on small-scale factors that are not adequately described by the ecotope variables. The trilateral map of the Wadden Sea contains two of such eco-elements, i.e. mussel/oyster beds and seagrass meadows. The data file is a zipped file containing a folder SHPdir that has: - Shapefile of the ecotopes (EcotopeWS3_mp). - Shapefile of the boundaries of 39 tidal basins (tidalbasins_ETRS_1989_UTM32). - Shapefile of the eco-element mussel/oysterbeds (bivbeds_focc). - Shapefile of the eco-element seagrass meadows (eelgras_presence). - Style Layer Descriptor (SLD)-files including PNG-files that show sediment-properties. - Excel-file showing the coding-scheme of the ecotopes (linked with .dbf-attribute table of the shapefile of the ecotopes).