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Full-Text Articles in Social and Behavioral Sciences

Responses Of Plants In Polar Regions To Uvb Exposure : A Meta-Analysis, K. K. Newsham, Sharon A. Robinson Nov 2009

Responses Of Plants In Polar Regions To Uvb Exposure : A Meta-Analysis, K. K. Newsham, Sharon A. Robinson

Sharon Robinson

We report a meta-analysis of data from 34 field studies into the effects of UV-B radiation on Arctic and Antarctic bryophytes and angiosperms. The studies measured plant responses to decreases in UV-B radiation under screens, natural fluctuations in UV-B irradiance, or increases in UV-B radiation applied from fluorescent UV lamps. Exposure to UV-B radiation was found to increase the concentrations of UV-B absorbing compounds in leaves or thalli by 7% and 25% (expressed on a mass or area basis, respectively). UV-B exposure also reduced aboveground biomass and plant height by 15% and 10%, respectively, and increased DNA damage by 90%. …


Desiccation Protects Antarctic Mosses From Ultraviolet-B Induced Dna Damage, Johanna Turnbull, Sharon A. Robinson, Simon J. Leslie Jan 2009

Desiccation Protects Antarctic Mosses From Ultraviolet-B Induced Dna Damage, Johanna Turnbull, Sharon A. Robinson, Simon J. Leslie

Faculty of Science - Papers (Archive)

Antarctic mosses live in a frozen desert, and are characterised by the ability to survive desiccation. They can tolerate multiple desiccation-rehydration events over the summer growing season. As a result of recent ozone depletion, such mosses may also be exposed to ultraviolet-B radiation while desiccated. The ultraviolet-B susceptibility of Antarctic moss species was examined in a laboratory experiment that tested whether desiccated or hydrated mosses accumulated more DNA damage under enhanced ultraviolet-B radiation. Accumulation of cyclobutane pyrimidine dimers and pyrimidine (64) pyrimidone dimers was measured in moss samples collected from the field and then exposed to ultraviolet-B radiation in either …


Antarctic Climate Change And The Environment, P C. Convey, R Bindschadler, G Di Prisco, E Fahrbach, J Gutt, D A. Hodgson, P Mayewski, C P. Summerhayes, J Turner, Sharon A. Robinson Jan 2009

Antarctic Climate Change And The Environment, P C. Convey, R Bindschadler, G Di Prisco, E Fahrbach, J Gutt, D A. Hodgson, P Mayewski, C P. Summerhayes, J Turner, Sharon A. Robinson

Faculty of Science, Medicine and Health - Papers: part A

The Antarctic climate system varies on timescales from orbital, through millennial to sub-annual, and is closely coupled to other parts of the global climate system. We review these variations from the perspective of the geological and glaciological records and the recent historical period from which we have instrumental data (the last 50 years). We consider their consequences for the biosphere, and show how the latest numerical models project changes into the future, taking into account human actions in the form of the release of greenhouse gases and chlorofluorocarbons into the atmosphere. In doing so, we provide an essential Southern Hemisphere …


Responses Of Plants In Polar Regions To Uvb Exposure : A Meta-Analysis, K. K. Newsham, Sharon A. Robinson Jan 2009

Responses Of Plants In Polar Regions To Uvb Exposure : A Meta-Analysis, K. K. Newsham, Sharon A. Robinson

Faculty of Science - Papers (Archive)

We report a meta-analysis of data from 34 field studies into the effects of UV-B radiation on Arctic and Antarctic bryophytes and angiosperms. The studies measured plant responses to decreases in UV-B radiation under screens, natural fluctuations in UV-B irradiance, or increases in UV-B radiation applied from fluorescent UV lamps. Exposure to UV-B radiation was found to increase the concentrations of UV-B absorbing compounds in leaves or thalli by 7% and 25% (expressed on a mass or area basis, respectively). UV-B exposure also reduced aboveground biomass and plant height by 15% and 10%, respectively, and increased DNA damage by 90%. …