In order to assess Berlin’s soil associations in regard to their soil quality, sensitivities and pollution, it is necessary to analyse their ecological properties, while also gaining a general understanding of their distribution and heterogeneity in the municipal area (cf. Map 01.01). This primarily involves examining characteristic values regarding the chemistry, physical state and water balance of the soil. While these values are primarily defined by the soil associations, they may also be substantially influenced by current land use.
The soil-scientific characteristic values described here have been derived from the soil associations, while also considering land use (cf. Maps 06.01 and 06.02). It was assumed that, within the desired level of accuracy, the characteristic values remain consistent across all areas sharing the same combination of soil association and land use.
The characteristic values for every combination of land use and soil association were gathered from existing documents and established as representative values. The primary source of this data was the companion volume to the map of soil associations (Dissertation, Grenzius 1987), which documents landscape segments and sample profiles of particular soil associations, based largely on measurements conducted by the Soil Science Department of the Technical University of Berlin (TU Berlin). In addition, various other soil-scientific maps were consulted, along with the results of the extensive soil analyses carried out as part of the Heavy-Metal Investigation Programme for humus content and pH values. For certain combinations, no measurements were available. In these cases, experts estimated the values based on data available for comparable land uses or comparable soil associations. Due to the variable number of measurements available per combination and the large number of inferred conclusions, the precision of the values presented varies greatly.
For most characteristic values, data is provided separately for the topsoil (0 to 10 cm) and the subsoil (90 to 100 cm).
Due to the map scale, the legend items associated with the soil map may represent soil associations with highly heterogeneous soil-ecological properties. To simplify the presentation, the complexity of ecological conditions has been greatly reduced by associating characteristic values with a typical soil type within their soil association. Therefore, the soil-scientific database contains not only the representative value (e.g. typical pH value) but also the maximum and minimum values, which are available for further evaluation.
For these reasons, the maps are designed for general purposes only at a scale of 1 : 50,000 and cannot replace individual site-specific investigations.