Most of the ecosystems suffer from anthropogenic pollution in form of chemical contamination or physical stressors. Currently, the effects of multi-stressors on various ecosystems have been analyzed at different levels of biological integrations making a distinction between lower such genetic-cell level and higher individual-population level. However, the linkage between reactions from stressors on genetic and population levels has not been studied to large extent. Although, response to stressors on genetic level did not get much attention in ecotoxicology for assessment of ecological risks, genetic change is very susceptible to pollution which may lead to long-term consequences. In this research the focus will be given to several questions: 1. To what extent do responses at genetic level predict (estimate) population-level responses? 2. Is it possible to translate gene expression changes in response to stressors into responses at population level for different species? 3. What are the methods to link responses at genetic level to population level responses?