State of knowledge of enchytraeid communities in German soils as a basis for biological soil quality assessment
Within a project aiming to improve the preconditions for the protection of the habitat function of soils in Germany, the database ‘Bo-Info’ was established. In this database soil biological data from permanent soil monitoring sites of several German states as well as from the literature were compiled. Soil biological data on the abundance and dominance of Enchytraeidae (potworms) were analysed with respect to their distribution, site characteristics (habitat type, land use) and soil properties (pH, texture, organic matter). Reliable data for potworms were available from 133 of 208 sites. In total, 96 species of the 122 species known to occur in Germany were present in the database, 24 of which were very common. Ecological preferences regarding land use, pH, soil organic matter (SOM) and soil texture were derived for these 24 plus another 16 species typical for specific habitat types. The occurrence of enchytraeids at the species and ecological-group level was most strongly determined by land use and pH value and less by soil texture. A distinction between litter and soil dwelling species was found regarding SOM. Enchytraeid communities of habitat types representing the four major land use types (grassland, arable land, deciduous and coniferous forests) clearly differed. Using three examples from different land use forms, typical species could be identified at the second level of detail of habitat types, given a sufficient number of data. As a result, qualitative expectation (= reference) values for species richness and composition are proposed for the most important habitat types (e.g. different types of arable land, grassland and coniferous forests). The data basis regarding taxonomy, biogeography and ecology of German enchytraeids clearly needs to be enlarged. Due to their ecological relevance, the use of enchytraeids for soil biological site classification and assessment is recommended.
Biogeography | habitat function | Enchytraeidae | permanent soil monitoring sites | reference system | Oligochaeta | Clitellata