Sublethal effects of heavy metal contamination on marine sponges: Responses at different biological levels

by Cebrian Pujol, Emma

SUMMARY: Many antrophic activities release pollutants to the marine environment. Among them heavy metals are of great importance, since they are conservative pollutants, which can be accumulated through trophy chains. Sometimes, the liberation to the marine waters is acute and drastic, leading to massive mortalities. However, more often, the liberation is by means of low and chronic concentrations. The main objective of the present thesis is to analyze the sponge responses in face to sublethal concentrations of heavy metals and to determine, if it is possible, whether they can be used as biomonitors of such kind of pollution. First, we have studied their availability to accumulate havey metals in both, temporal and especial scales. And then, by means of the use of different biomarkers, to analyze the sublethal effects of heavy metals on sponges at different levels of biological organization, from molecules to populations. The present thesis has been performed by means of experiments in situ and at the laboratory, in order to elucidate heavy metal accumulation patterns and their effects depending on the specie and metal considered.