Our research examined the influence of ultraviolet-B radiation (UV-B) and warming on the performance of Antarctic flowering plants (i.e. Deschampsia antarctica, Antarctic hairgrass and Colobanthus quitensis, Antarctic pearlwort). Our research endeavors fell into the following categories:
1) ... We conducted a long-term field experiment at Stepping Stones, near Palmer Station, in which we reduced levels of UV radiation and raised air temperatures around naturally growing Deschampsia antarctica and Colobanthus quitensis plants for four consecutive growing seasons. We examined plant responses to these manipulations by assessing photosynthesis, vegetative growth, cover, and sexual reproduction. At the end of this experiment, we collected plant, soil and litter samples, and examined treatment effects on plant biomass production, litter accumulation, soil properties, and microarthropod populations.
2) Single growing-season experiments were also conducted at Stepping Stones, primarily aimed at examining the influence of UV-B radiation on plant growth processes and concentrations of UV-screening compounds in leaves, and soil seed banks.
3) We also conducted a more intensive short-term experiment at Palmer Station, in which we placed potted plants under UV-B transparent or UV-B absorbing filters from November through late December, corresponding to the ozone depletion/enhanced UV-B season. We assessed the influence of ambient UV-B during the ozone depletion period by examining UV-screening compound concentrations, and rates of photosynthesis, plant growth and DNA damage.
4) To quantify the short-term UV-B responses of these species under more controlled conditions, we examined the UV dose response of DNA damage and screening compound concentrations in these species in growth chamber studies at our home institution.
5) We examined the temperature response of antarctic plants, by characterizing the photosynthetic and respiratory responses of naturally growing plants to temperature at Palmer Station. We also characterized their long-term, or acclimation, responses to rising temperatures, in terms of photosynthesis, respiration and growth, in a series of growth chamber experiments.
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Data Set Citation
Impacts of climate change on Antarctic vascular plants: warming and UV-B radiation
Department of Plant Biology, Arizona State University
Department of Plant Biology
Life Sciences E-218
PO Box 871601
Arizona State University
Province or State:
Grobe, CW, CT Ruhland & TA Day. 1997. A new population of the vascular plant Colobanthus quitensis (Kunth) Bartl. at Arthur Harbor, Antarctic Peninsula: correlating recruitment with warmer summer air temperatures. Arctic and Alpine Research 29:217-221.
McGraw, JB & TA Day. 1997. Size and characterization of ... a natural seed bank in Antarctica. Arctic and Alpine Research 29:213-216.
Day, TA, CT Ruhland, CW Grobe & F Xiong. 1999. Growth and reproduction of Antarctic vascular plants in response to warming and UV-B radiation reductions in the field. Oecologia 119:24-35.
Xiong, F, CT Ruhland & TA Day. 1999. Photosynthetic temperature response of the Antarctic vascular plants Colobanthus quitensis and Deschampsia antarctica. Physiologia Plantarum 106:276-286.
Xiong, F, EC Mueller & TA Day. 2000. Photosynthetic and respiratory acclimation and growth response of Antarctic vascular plants to contrasting temperature regimes. American Journal of Botany 87:700-710.
Ruhland, CT & TA Day. 2000. Effects of ultraviolet-B radiation on leaf elongation, production and phenylpropanoid concentrations of Deschampsia antarctica and Colobanthus quitensis in Antarctica. Physiologia Plantarum 109:244-251.
Xiong, F & TA Day. 2001. Effect of solar ultraviolet-B radiation during springtime ozone depletion on photosynthesis and biomass production of Antarctic vascular plants. Plant Physiology 125:738-751.
Ruhland, CT & TA Day. 2001. Size and longevity of seedbanks in Antarctica and the influence of ultraviolet-B radiation on survivorship, growth and pigment concentrations of Colobanthus quitensis seedlings. Environmental and Experimental Botany 45:143-154.
Day, TA, CT Ruhland, & F Xiong. 2001. Influence of solar ultraviolet-B radiation on Antarctic terrestrial plants: results from a 4-year field study. Journal of Photochemistry and Photobiology B: Biology 62:78-87.
Day, TA. 2001. Multiple trophic levels in UV-B assessments - completing the ecosystem. New Phytologist 152:183-186.
Convey, P, PJA Pugh, C Jackson, AW Murray, CT Ruhland, FS Xiong & TA Day. 2002. Response of Antarctic terrestrial microarthropods to multifactorial climate manipulation over a four year period. Ecology, in press.
Xiong, FS, Ruhland, CT & TA Day. 2002. Effect of ultraviolet-B radiation on growth of Colobanthus quitensis at Palmer Station, Antarctica. Global Change Biology, in press.