GHORMA MoussaGHOZLENE Djalel2024-02-292024-02-292017577-043-Mhttp://dspace.univ-khenchela.dz:4000/handle/123456789/2477Abstract In this experimental study we were interested in the evaluation of impacts pollution of the grounds of some biotopes of Khenchela by the use of a bioindicator, Helix aspersa, (Mollusca, Gasteropoda), snail very abandant on the level of four sites study. The physicochemical analysis of grounds reveals us that we are in the presence of ground with argilo-muddy texture, slightly basic (pH > 7,5) no saline (conductivity, 1-0,3 m mohs/cm), who retain little hygroscopic moisture and who have a rather strong porosity between 10-20% in the four sites of studies. The proportioning of two biomarqueurs (AChE and GST) reveals that the sites of Fais, Kais and El-Hamma. Ain Toiula is the site less polluted.frThesis