Potential use of freshwater molluscs for monitoring river pollution

Abstract

To control the increasing pollution of streams in urban and industrial areas, ecological criteria such as indicator properties of organisms and biocoenoses are required. Hereby, the distribution and abundance of populations is determined by their genetic structure, that react in different ways to the intensity of burdening parameters.The Saar River is excessively polluted by industrial sewage, thermal wastes and chemicals. Therefore monitoring programs were established to analyze the structure of benthic populations in order to control the influence of the present pollution of the river.Genetic and popu|ation-eco|ogicat analyses of the freshwater gastropod Physa acuta Drap. indicate gradually significant differences in the allele frequencies and their heterozygoties. The results demonstrate correlated strategies in different populagions, whereby balanced allele frequency distribution patterns indicate the influence of the toxic substances.These analyses Serve for a better understanding of evolutionary processes in urban environments as well as for an objective consideration of the indicator systems by detecting changes before the extinction of a taxon.

Biological assessment of the Zayandeh Rud River, Iran, using benthic macroinvertebrates

“…The seventh station was dominated by Physa acuta (Gastropoda) and Oligochaeta, which are known to be able to tolerate unfavorable conditions such as low dissolved oxygen and high pollutant concentrations (Zadory and Müller, 1981;Brinkhurst, 1967). The results of water quality parameters showed that the river was highly polluted at S 7 .…”

Toxicological and Biochemical Investigation of certain Herbicides on Culex pipiens L. (Diptera: Culicidae) Mosquitoes under Laboratory Conditions

“…Negatively, persistence of some herbicides (e.g., glyphosate) on mosquitoes aquatic breeding sites led to increase the mosquitoes resistance to various types of pesticides and that action have been occurred through inductions of some detoxification enzymes in these pests which involved in the metabolism and degradation of these pesticides [27][28]. In this interim, some genetics methods such as isozyme analysis and sodium dodecyl sulphate-total protein (SDS-total protein) have been utilized as a bio-indicator assay for the changes occurred in the molecular basis in organisms (i.e., insects and snails) exposed to different types of xenobiotic and the environmental stress such as accumulation of pollutants [19,29].…”