Artic Ecosystems and UV-radiation

Fortunately, a long time interest for the Arctic can be combined with research in the same area. Our group has done reseach on UV-radiation and effects on aquatic ecosystems for years in the beautiful vicinity of Ny-Ålesund at Svalbard, and this has been supplemented by laboratory experiments. Some more info on this is available at www.viten.com/nyviten/hessen.htm. Based on our own studies, and that of colleagues, the role of UV-radiation on Arctic ecosystems was covered in the book UV-radiation and Arctic Ecosystems (ed. D.O. Hessen) at Springer Publishers (see books). The book covers all aspects from ozone depletion to effects on bacteria and phytoplankton to humans , focussing the arctic where the most severe effects of ozone depletion would be anticipated.

While the Montreal Protocol on substances that deplete the ozone layer is a landmark international agreement designed to protect the stratospheric ozone layer. The treaty was originally signed in 1987 and substantially amended in 1990 and 1992. The Montreal Protocol stipulates that the production and consumption of compounds that deplete ozone in the stratosphere--chlorofluorocarbons (CFCs), halons, carbon tetrachloride, and methyl chloroform--are to be phased out. Yet in spite of these substantial efforts, many countries have still not signed the protocol, ozone destructive substances have also a long life in the atmosphere, and - more alarming - global warming seem to induce cooling of the upper stratosphere, an effect that is crucial for ozone depletion. Hence in spring 2005 the lowest ozone concentrations ever recorded over the Northern hemisphere caused a substantial increase in UV-radiation in early spring, by the time of the spring bloom of marine phytoplankton. Phytoplankton in not only important for sequestering CO2 from the atmosphere, it also forms the basis for the entire marine food web. Thus there will be continued needs for UV-related research in the Arctic.

Our more recent efforts deals with the role of UV-radiation for synthesis of the crucial fatty acids, notably the polyunsaturated fatty acids, in marine and freshwater food webs, as well as the role of UV for coupled uptake of carbon, nitrogen and phosphorus in algae. We have found some highly intriguing results here that are soon to be published. For a Norwegian audience, some hints can be found at: http://www.apollon.uio.no/vis/art/2005_3/artikler/uv_straaling_svalbard

We are currently also running other project with Arctic affinities. Some are related to the genetic structure and diversity of arctic species, like our circumpolar study on the "living fossil" Lepidurus (skjoldkreps, tadpole shrimp) and various studies on Daphnia. The recent efforts here are devoted to the selection for fast growth rate via high levels of RNA and high rates of protein synthesis under low temperatures in various Arctic invertebrates, and the role of polyploidy (multiple chromosome copies) together with plant scientists.

 

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Creatures resting on icebergs Arctic flora Creatures resting on icebergs UV-radiation experiments