A new ecological tool to detect chemical and physical stressors through the analysis of gregarious behaviour in terrestrial isopods
The research team of the MUSA Spoke 1 project presented the results of an innovative study entitled Disaggregation behaviour in the terrestrial isopod Porcellionides pruinosus as a new ecotoxicological endpoint for assessing infochemical disrupting activity. The group developed a new biosensor capable of rapidly and inexpensively determining the presence of disrupting elements, mainly chemical and physical stressors, in the soil. This tool uses two integrated ecological indices to quantify alterations in the gregarious behaviour of terrestrial isopods, offering an effective assessment of the health of terrestrial ecosystems.
The research team includes Dr Lorenzo Federico and professor Sara Villa from the Department of Earth and Environmental Sciences at the University of Milan-Bicocca, together with professor Gianna Serafina Monti from the Department of Economics, Management and Statistics at the same university, and professor Susana Loureiro from the Centre for Environmental and Marine Studies and the Department of Biology at the University of Aveiro.
As stated in the publication: ‘In recent years, there has been a significant increase in interest in the impact of contaminants and stressors on soil population dynamics, in line with the ecotoxicological paradigm developed in the study of ecological stress. Therefore, understanding the ethological traits associated with the migration or communication of edaphic populations, as well as the effects of contaminants and multiple stressors on their ecological niche, contributes to improving ecological realism within the framework of ecotoxicological risk assessment.’
The study introduces a new ecotoxicological endpoint related to the disaggregation effect, which allows for the rapid detection of chemicals that interfere with intraspecific communication and influence avoidance behaviour. The quantification of the disaggregation index (DI) and group disaggregation (DG) allowed the determination of EC50 values useful in the regulatory context. The study showed how exposure to certain contaminants induces terrestrial isopods to migrate to the control soil, maintaining aggregation within a certain concentration range, while higher concentrations cause disaggregation behaviour.
Future studies will focus on understanding the potential molecular mechanisms underlying the disaggregation effect in individuals of Porcellionides pruinosus, in order to confirm the alteration of gregarious behaviour induced by soil contamination.
