Calculation of an ecological land classification of Europe | Berechnung einer landschaftsökologischen Raumgliederung Europas

GOAL, SCOPE, AND BACKGROUND: In this first article of the series the calculation of the ecological regionalisation of Europe is described. Amongst others, the ecological regionalisation should be used for the optimisation of European environmental monitoring networks. MATERIALS AND METHODS: The land classification was calculated from surface data on the potential natural vegetation, soil texture and climate with both Classification and Regression Trees and Chisquare Interaction Detection. Europe was divided into zones on the basis of the main formations of the potential natural vegetation. According to the percentage of the surface area covered by each of the areas the respective number of ecologically defined regions were separately calculated. Subsequently the spatial classes were integrated into a comprehensive classification of Europe. RESULTS: The ecoregionalisations calculated by Classification and Regression Trees and Chisquare Interaction Detection were compared with respect to several criteria. Accordingly, the results derived by means of Classification and Regression Trees could be proved to be preferable to those computed by means of Chisquare Interaction Detection. Each of the land classes can be characterized regarding its ecological properties. This is exemplified by the biggest classes of the land classification with 40 classes. DISCUSSION: The results gathered by means of Classification and Regression Trees should be detailed in a further article. The discussion on the data used concentrates on the potential natural vegetation. Referring to the literature the potential natural vegetation can be seen as reasonable basis for the calculation in terms of ecological theory. CONCLUSIONS: Classification and Regression Trees could be proved to be an appropriate method for the calculation of ecoregionalisations which fulfil the quality criteria such as, e.g., reproducibility. Such a classification is an important instrument for monitoring the environment, because it helps to test quantitatively the representativity of monitoring sites according to the spatial resolution of the data used for the ecoregionalisation. RECOMMENDATIONS: The ecological land classification should be used for the assessment of monitoring networks from which the data are compiled for evaluations of the environmental condition in Europe. In this context, the implementation of the regionalisation and the measurement networks in a WebGIS could be useful. OUTLOOK: In the following article of the series an elaborate description of 40 ecoregions of Europe will be given. In a further article existing ecoregionalisations of Europe will be compared to the classification computed by means of Classification and Regression Trees. Another article will focus on the investigation of the representativity of environmental monitoring networks with respect to the ecological coverage presented in this article.