Bioinertization strategy by Bivalves: A new challenging technique also for CO2 balance.

Areas such as mangroves, salt marshes and seagrasses are known to be responsible for capturing and storing up to some 70 % of the carbon permanently stored in the marine system. The so called “Blue carbon” is thus emerging as another option for controlling climate change because of marine systems ability to sequester vast amounts of carbon dioxide and consequently to act as a carbon sink. In this optic it is important to better understand coastal ecosystem functioning and to quantify the contribution of the singular components in order to improve this ability. We focused our attention on a seagrass, i.e. the Venice Lagoon coastal transition environment, and we tried to estimates the importance of the role of living organisms in capturing atmospheric carbon dioxide and transform it in a storable form. First we considered the autotrophic component and its capacity to fix CO2 as organic matter photosyntheticaly; then, we tried to follow the flow of this carbon in the food web and in particular towards skeletal molluscan organisms. On the other side it’s known that the crystalline calcium carbonate lattice is able to incorporate metals. This is the reason why Bivalves are extensively used in biomonitoring programmes being efficient accumulators of contaminants and ideal bioindicators. Various species have been used for assess toxic metals levels in marine environment but the most favourite ones are filter feeding Bivalves such as mussels and oysters. This skill could be used in future applications concerning the comprehension and the following exploitation of Bivalves role in water basin self-purification mechanisms. The comprehension of the relevance of these mechanisms enable us to imagine a new challenging frontier: the exploitation of molluscan commercial production as a mean for carbon sequestration and pollutants bioinertization.