Exposure to solar UV radiation leads to adverse effects on the biosphere including terrestrial and aquatic ecosystems as well as public health. Several plants react to increased UV radiation with reduced growth or diminished photosynthetic activity.
Some of the adverse effects of the UV irradiance may relate to the frequency of the extreme UV-B events or to UV doses at particular times of the year (such as those that Antarctic plants undergo annually the late winter/spring as a consequence of the ozone hole). However, other adverse effects of the UV irradiance may be strictly proportional to cumulative UV dose. Not all the parts of a plant have the same exposure to solar UV radiation; the UV dose affecting plants depends on the UV radiance distribution (the radiance is defined as radiant flux per differential solid angle and surface element).
Due to in Worldwide the radiance has not been as extensively examined as irradiance, this project has planned to set up a sky scanner system, which will comply with strict specifications and thus will allow us to tie our ground-based spectral UV radiance measurements into international programs. It is expected that the high quality ground-based UV datasets will enable to assess the influence of the albedo and the cloud conditions on the UV radiance distribution in Antarctica. The observations should enable us to determine some of the characteristic of the local surface UV climatology, and therefore to generate better estimations of the UV doses on endemic species.
This research on the UV-linked effects will be focused on the cuticles and on the DNA molecules of some Antarctic species. In order to understand the mechanism of DNA mutagenesis, it is fundamental to know how DNA in different conformations is affected by UV light. It is expected that by analyzing the extent of the change in the properties of the DNA molecule due to the UV radiation, the UV-linked damage on DNA conformation will be assessed. Moreover, we expect that our planned tests on the UV-linked effects (on the cuticles and on the DNA molecules) will allow us to integrate our research into the ongoing global effort of assessing the biological effects of climate change.
Raúl Cordero (Anillo Director)
Luis Da Silva