What can gastropod assemblages tell us about freshwater environments?

TIETZE, ELEONOR; DE FRANCESCO, CLAUDIO GERMÁN; NÚÑEZ, MARIA VERÓNICA

Gastropods: Diversity, Habitat and Genetics

Nova Science Publishers

Lugar: New York; Año: 2011; p. 1 - 36

Gastropods are among the most ubiquitous shelly remains preserved in Quaternary non-marine sediments of the Neotropical Region, constituting an invaluable source of data for reconstructing past environments, in particular the hydrodynamics of past water bodies. There are several of these species that are widely known of being good indicators of environmental conditions. Worldwide studies over the last 40 years have returned strong positive correlations between the abundance and/or diversity of freshwaters mollusks and water quality variables. However, the absence of ecological data for many species as well as a general inadequacy in our understanding of the factors controlling their distribution has limited their broad use as paleoecological indicators. This situation is particularly worrying in Argentina where the scarce ecological information existent is scattered in studies with different objectives, most of them published in local journals of difficult access for an international audience. As an example in the Pampean Region, which constitutes the most studied area in the country, a total of 23 species belonging to Ampullaridae, Cochliopidae, Chilinidae, Lymnaeidae, Planorbidae and Physidae has been recorded. In the present chapter ecological aspects of these species are reviewed in order to provide a synthesis of the works from previous years through the present day, seeking to unify criteria. Besides, the statistics applied to the analyses of the relationship between these organisms and environmental factors are also discussed. The final aim is to contribute to an understanding of the value freshwater snails as paleoenvironmental indicators.