Groundwater fauna in an urban area – natural or affected?

Abstract. In Germany, 70 % of the drinking water demand is met by groundwater, for which quality product multiple physical–chemical and biological processes. As healthy groundwater ecosystems help to provide clean water, it necessary assess their ecological conditions. This particularly true densely populated urban areas, where faunistic investigations are still scarce. The aim this study is, therefore, a first assessment fauna in an area. Thus, we examine status anthropogenically influenced aquifer analysing 39 monitoring wells city Karlsruhe (Germany). For classification, apply ecosystem index (GESI), threshold more than crustaceans less 20 oligochaetes serves as indication very good Our reveals that only 35 residential, commercial industrial areas 50 forested area fulfil these criteria. However, did not find clear spatial patterns with respect land use other anthropogenic impacts, particular temperature. Nevertheless, there noticeable differences distribution species combination abiotic characteristics different city, indicate comprehensive required evaluate detail. particular, indicators, such temperature, indicator species, delineation site-specific natural reference conditions should be considered.