Groundwater Fauna Associated with Riverine Aquifers

Abstract

Groundwater ecology, especially that dealing with subterranean fauna, developed more slowly than other branches of limnology. In recent years a revival of interest can be seen in Europe and North America. Recent developments in Europe are reviewed. Riverine aquifers can be considered macro-ecosystems. A conceptual model for the Danube aquifer in the alluvial plain of the Vienna Basin is presented. Progress in the study of the ecology of the animal assemblages from superficial alluvial sediments is discussed. 1. The interstitial habitat of the backwaters in alluvial plains of rivers harbours a diverse and abundant fauna; this is exemplified with data from the Danube wetland in the Vienna Basin as well as from the Rhone plain. 2. The use of fixed stand-pipes disposed within a regular grid, combined with the Bou-Rouch method of pumping groundwater, allows a better description of the faunistic assemblages. 3. It is emphasized that some taxocenes, like the crustacean Ostracoda, display on a larger scale (m) a diversity pattern that can be described mathematically using a log linear model. The practical use of groundwater assemblages for monitoring environmental situations is discussed. A modern approach to the ecology of the groundwater fauna is to consider it within an individualistic and historical perspective. It is emphasized that groundwater animals migrate actively within the interstitial space and are able to find their preferred habitat. They can transform their microenvironment too. Within a historical approach the groundwater ecologist has to investigate phylogenetically related species in order to better understand the origin and evolution of the subterranean dwellers, e.g., the degree of adaptation to the subsurface environment. The succession of historical events is important for an understanding of the spatial distribution of the groundwater fauna. The protection of subterranean animals and their habitats has a cultural and practical value. More basic research within a multidisciplinary framework is emphasized as a prerequisite for the achievement of further developments in groundwater ecology.