Trace metals in Antarctica related to climate change and increasing human impact

• Main Author: BARGAGLI, R.
• Other Authors: Bargagli, R.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2000
• Subjects: Antarctic; Arctic; Southern Ocean; The Antarctic; Antarc*; Antarctica; Climate change
• Online Access: http://hdl.handle.net/11365/6431

Metals are natural constituents of the abiotic and biotic components of all ecosystems, and under natural conditions they are cycled within and between the geochemical spheres - the atmosphere, lithosphere, hydrosphere, and biosphere - at quite steady fluxes. In the second half of the twentieth century, the huge increase in energy and mineral consumption determined anthropogenic emissions of several metals exceeding those from natural sources, e.g., volcanoes and windborne soil particles. In the Northern Hemisphere, the biogeochemical cycles of Pb, Cd, Zn, Cu, and other metals were significantly altered, even in Arctic regions. On the contrary, available data on trace metal concentrations in abiotic matrices from continental Antarctica, summarized in this review, suggest that the biogeochemical cycle of Pb is probably the only one that has been significantly altered by anthropogenic emissions in Antarctica and elsewhere in the Southern Hemisphere, especially in the period 1950-1975. Environmental contamination by other metals from anthropogenic sources in Antarctica itself can generally only be detected in snow samples taken within a range of a few kilometers or several hundred meters from scientific stations. Local metal pollution from human activities in Antarctica may compromise studies aimed at assessing the biogeochemical cycle of trace elements and the effects of global climate change. Thus, this review focuses on concentrations of metals in atmospheric particulate, snow, surface soils, and freshwater from the Antarctic continent and surface sediments and seawater from the Southern Ocean, which can plausibly be regarded as global background values of trace elements. These baselines are also necessary in view of the construction of new stations, the expansion of existing facilities to support research, and the growth of tourism and fisheries. Despite difficulties in making comparisons with data from other remote areas of the world, concentrations of trace metals in most samples of atmospheric particulates, ...