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Articles 1 - 6 of 6
Full-Text Articles in Physical Sciences and Mathematics
Bryophyte Species Composition Over Moisture Gradients In The Windmill Islands, East Antarctica: Development Of A Baseline For Monitoring Climate Change Impacts, J Wasley, S A. Robinson, J D. Turnbull, D H. King, W Wanek, M Popp
Bryophyte Species Composition Over Moisture Gradients In The Windmill Islands, East Antarctica: Development Of A Baseline For Monitoring Climate Change Impacts, J Wasley, S A. Robinson, J D. Turnbull, D H. King, W Wanek, M Popp
Faculty of Science - Papers (Archive)
Extreme environmental conditions prevail on the Antarctic continent and limit plant diversity to cryptogamic communities, dominated by bryophytes and lichens. Even small abiotic shifts, associated with climate change, are likely to have pronounced impacts on these communities that currently exist at their physiological limit of survival. Changes to moisture availability, due to precipitation shifts or alterations to permanent snow reserves, will most likely cause greatest impact. In order to establish a baseline for determining the effect of climate change on continental Antarctic terrestrial communities and to better understand bryophyte species distributions in relation to moisture in a floristically important Antarctic …
Late Pliocene Age Of Glacial Deposits At Heidemann Valley East Antarctica: Evidence For The Last Major Glaciation In The Vestfold Hills, Eric Colhoun, Kevin W. Kiernan, Anne Mcconnell, P G Quilty, David Fink, Colin V. Murray-Wallace, J M Whitehead
Late Pliocene Age Of Glacial Deposits At Heidemann Valley East Antarctica: Evidence For The Last Major Glaciation In The Vestfold Hills, Eric Colhoun, Kevin W. Kiernan, Anne Mcconnell, P G Quilty, David Fink, Colin V. Murray-Wallace, J M Whitehead
Faculty of Science - Papers (Archive)
No abstract provided.
Accumulation Of Dna Damage In Antarctic Mosses: Correlations With Ultraviolet-B Radiation, Temperature And Turf Water Content Vary Amongst Species, J. D. Turnbull, Sharon A. Robinson
Accumulation Of Dna Damage In Antarctic Mosses: Correlations With Ultraviolet-B Radiation, Temperature And Turf Water Content Vary Amongst Species, J. D. Turnbull, Sharon A. Robinson
Faculty of Science - Papers (Archive)
The susceptibility of three East Antarctic moss species to UV-B radiation was examined by measuring accumulation of cyclobutane pyrimidine dimers under natural sunlight during the austral summer season of 2002/03. The 2002/03 season was characterised by unusually low springtime ozone depletion and as such our results likely underestimate the DNA damage possible in a more typical UV-B radiation season. Despite this all three species accumulated significant DNA photoproducts. We also found a positive association between photoproduct accumulation and incident UV-B radiation in the two cosmopolitan species, Bryum pseudotriquetrum and Ceratodon purpureus, with more DNA damage in samples collected early …
Somatic Mutation And The Antarctic Ozone Hole, L. J. Clarke, Sharon A. Robinson, D. J. Ayre
Somatic Mutation And The Antarctic Ozone Hole, L. J. Clarke, Sharon A. Robinson, D. J. Ayre
Faculty of Science - Papers (Archive)
1 Previous studies of Antarctic clonal moss populations using RAPD markers have reported extraordinarily high levels of genetic variation. This has been claimed to reflect somatic mutation, possibly resulting from elevated UV-B radiation. 2 Our study used microsatellite markers to compare the genetic variation present within continental Antarctic, sub-Antarctic and temperate populations of the moss Ceratodon purpureus. 3 In contrast to the RAPD studies, microsatellite data revealed that C. purpureus populations from continental Antarctica display less intra-population genetic diversity than populations from a range of temperate and sub-Antarctic sites. 4 Analysis of Molecular Variation (AMOVA) revealed that populations within the …
Uv-B Screening Potential Is Higher In Two Cosmopolitan Moss Species Than In A Co-Occurring Antarctic Endemic Moss – Implications Of Continuing Ozone Depletion, J. L. Dunn, Sharon A. Robinson
Uv-B Screening Potential Is Higher In Two Cosmopolitan Moss Species Than In A Co-Occurring Antarctic Endemic Moss – Implications Of Continuing Ozone Depletion, J. L. Dunn, Sharon A. Robinson
Faculty of Science - Papers (Archive)
Concentrations of UV-B absorbing pigments and anthocyanins were measured in three moss species, over a summer growing season in Antarctica. Pigment concentrations were compared with a range of climatic variables to determine if there was evidence that pigments were induced by UV-B radiation, or other environmental parameters, and secondly if there were differences between species in their pigment responses. Significant seasonal differences in the potential UV-B screening pigments were found, with the two cosmopolitan species Bryum pseudotriquetrum and Ceratodon purpureus appearing better protected from the potentially damaging effects of ozone depletion than the Antarctic endemic Schistidium antarctici. Bryum pseudotriquetrum accumulated …
Some Like It Wet – Biological Characteristics Underpinning Tolerance Of Extreme Water Stress Events In Antarctic Bryophytes., J. Wasley, Sharon A. Robinson, C. E. Lovelock, M. Popp
Some Like It Wet – Biological Characteristics Underpinning Tolerance Of Extreme Water Stress Events In Antarctic Bryophytes., J. Wasley, Sharon A. Robinson, C. E. Lovelock, M. Popp
Faculty of Science - Papers (Archive)
Antarctic bryophyte communities presently tolerate physiological extremes in water availability, surviving both desiccation and submergence events. This study investigated the relative ability of three Antarctic moss species to tolerate physiological extremes in water availability and identified physiological, morphological, and biochemical characteristics that assist species performance under such conditions. Tolerance of desiccation and submergence was investigated using chlorophyll fluorescence during a series of field- and laboratory-based water stress events. Turf water retention and degree of natural habitat submergence were determined from gametophyte shoot size and density and ?13C signatures respectively. Finally, compounds likely to assist membrane structure and function during desiccation …