Licht-im-Terrarium: Literaturdatenbank
Licht-im-Terrarium: Literaturdatenbank |
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Pahkala, M., Räsänen, K., Laurila, A., Johanson, U., Björn, L. O., & Merilä, J. (2002). Efectos letales y subletales del sinergismo b-uv/ph en embriones de rana común. Conservation Biology, 16(4), 1063–1073. Added by: Sarina (2013-09-19 10:20:15) Last edited by: Sarina (2013-09-19 10:20:26) |
| Resource type: Journal Article DOI: 10.1046/j.1523-1739.2002.00527.x ID no. (ISBN etc.): 1523-1739 BibTeX citation key: Pahkala2002 View all bibliographic details  |
Categories: Englisch = English Keywords: Amphibien = Amphibians, Ultraviolett = Ultraviolet Creators: Björn, Johanson, Laurila, Merilä, Pahkala, Räsänen Collection: Conservation Biology |
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| Abstract |
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Abstract: Although the negative effects of ultraviolet-B ( UV-B) radiation on the development of many amphibian species have been demonstrated, some species—such as the common frog ( Rana temporaria)—seem to be tolerant of UV-B radiation. The amount of UV-B radiation received is likely to vary among populations of the same species, but little is known about geographic variation in UV-B tolerance. Similarly, although UV-B radiation can have synergistic effects with other stressors, no studies have focused on geographic variation of these effects on amphibians. We investigated the synergistic effects of UV-B radiation and low pH on hatchability and early development of R. temporaria embryos in a factorial laboratory experiment with animals originating from southern and northern Sweden. Newly fertilized eggs were exposed to three different UV-B treatments (no UV-B [control], 1.254 k/J/m 2[normal] and 1.584 k/J/m 2[26% enhanced]) and two pH treatments (4.5 [low] and 7.6 [neutral]). Ultraviolet-B radiation in combination with low pH lead to markedly (approximately 50%) reduced survival rates and increased (approximately 30%) frequency of developmental anomalies in the northern but not in the southern population. The UV-B- exposed embryos hatched at smaller size in the southern population, whereas low pH reduced hatchling size in both populations. In both populations and pH treatments, embryos in the normal UV-B treatment developed significantly faster than embryos in the enhanced or control UV-B treatments. No interaction between pH and UV-B on developmental rates or hatchling size was detected. The results demonstrate—contrary to earlier belief—that R. temporaria embryos are not insensitive to increased levels of UV-B radiation. The lethal effects of UV-B radiation may, however, become manifested only in combination with other stressors, such as low pH, and the effects of this synergism may differ among different populations of the same species.
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