Shem

Spitsbergen, the largest of the Svalbard islands, is located on the border between the North Atlantic and the Arctic Ocean, and its marine ecosystems can be re­ garded as privileged observatories to investigate modifications related to climatic changes and anthropic impact.

Trace elements naturally occur in any ecosystem, but their concentration can be dramatically increased by human activity, representing a threat for the environment and health. In particular, heavy metals are introduced into the Arctic marine envi­ ronment by local inputs and long-range transport processes driven by oceanic and atmospheric circulation. Here, trace elements are uptaken by living organisms, ac­ cumulated in their tissues and organs and, for some elements, biomagnified through the marine food web.

The main goal of the project is hence to obtain a better knowledge of the occur­ rence, sources and transport pathways of heavy metals delivered to the Arctic via the marine suspended particulate, a major carrier of metals in the oceans. In par­ ticular, the study will focus on elements with a biological role, such as iron and copper, and contaminants of concern such as cadmium, mercury and lead.

Before each sampling, conductivity, temperature, density, fluorescence, and turbid­ ity will be determined along the water column by a CTD profiling probe. Then, sea­ water samples will be collected at various depths according to the CTD profile and the marine suspended particulate will be obtained by filtration through 0.4-µm polycarbonate filters. The samples will be analysed by atomic spectrometry tech­ niques for the determination of several major (Al, Fe, Na and Mg) and trace elementes ( Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, V and Zn). The obtained data will allow us to assess the contaminations of  seawater by heavy metals and to better understand the complex pathways by which these contaminations are delivered to Arctic from anthropogenic and natural sources.