ECOREGIONS AND ECODISTRICTS - ECOLOGICAL REGIONALIZATIONS FOR THE NETHERLANDS ENVIRONMENTAL-POLICY

For communicating data on the state of the environment to policy maker s, various integrative frameworks are used, including regional integra tion. For this kind of integration we have developed two related ecolo gical regionalizations, ecoregions and ecodistricts, which are two lev els in a series of classifications for hierarchically nested ecosystem s at different spatial scale levels. We explain the compilation of the maps from existing geographical data, demonstrating the relatively ho listic, a priori integrated approach. The resulting maps are submitted to discriminant analysis to test the consistancy of the use of mappin g characteristics, using data on individual abiotic ecosystem componen ts from a national database on a 1-km(2) grid. This reveals that the s patial patterns of soil, groundwater, and geomorphology correspond wit h the ecoregion and ecodistrict maps. Differences between the original maps and maps formed by automatically reclassifying 1-km(2) cells wit h these discriminant components are found to be few. These differences are discussed against the background of the principal dilemma between deductive, a priori integrated, and inductive, a posteriori, classifi cation.