Metal tolerance in marine algae - transplantation field experiments in Chile
Chile, with a shoreline of 6435 km, is one of the most biologically productive temperate marine macro-ecosystems in the world. The Humboldt Current combined with upwelling processes provides constant nutrient exchange which supports high coastal biodiversity including kelps that are the foundation for and bioengineers of food webs. Human habitation and industrial activity along the length of the country have negatively impacted these coastal ecosystems. Anthropogenic inputs of metals, mainly from mining activities, are the priority pollutants; metal stress disrupts marine communities, and represents a threat to human health as consequence of the consumption of metal contaminated resources.
Supervised by Dr Murray Brown
, Claudio Sáez Avaria
’s PhD research takes a multidisciplinary and holistic approach to marine pollution through his investigation of the mechanisms the model brown alga, Ectocarpus siliculosus
, has developed to counteract the effects of metal stress at different levels of biological organization with special emphasis in molecular and biochemical aspects. Using several cultured strains of E. siliculosus
in environmentally controlled laboratory experiments, Claudio is assessing the oxidative stress defence responses to copper and cadmium metal exposure by measuring different antioxidant, redox enzymes, metal chelators, and the expression of important genes involved in metal stress response. Although the latter can provide valuable information on specific metabolic responses against metal stress, they do not necessarily represent the mechanisms by which algae respond in natural, more complex, environments.
As a recipient of a Santander Postgraduate Mobility Support Scholarship
, Claudio will travel to Chile and perform transplantation experiments in metal polluted and non-polluted sites, in locations where some of the cultured strains originated. Due to the global distribution of Ectocarpus
in temperate latitudes, the data generated will be used to evaluate this seaweeds suitability as a bioindicator of metal pollution. This data will also aid in the development of reliable biochemical and molecular biomarkers for assessing the health status of the coastal environment. Claudio’s field research in Chile will strengthen research links between Plymouth University and Valparaiso University and Catholic University of the North, both located in Chile as well as build on existing links with academic institutions located in Italy, France, New Zealand and the UK.
Sáez, C.A., Lobos, M.G., Macaya, E., Oliva, D., Quiroz, W., Brown, M.T.. Variation in patterns of metal accumulation in thallus parts of Lessonia trabeculata (Laminariales; Phaeophyceae). Implications for biomonitoring. PLoS ONE (under review).
Sáez, C.A., Pérez-Matus, A., Lobos, M.G., Oliva, D., Vásquez, J.A., Bravo, M., 2012. Environmental assessment in a shallow subtidal rocky habitat: Approach coupling chemical and ecological tools. Chemistry and Ecology 28, 1-15.