Can bottom ice algae tolerate irradiance and temperature cha
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TitleCan bottom ice algae tolerate irradiance and temperature changes?AbstractSea ice algae are significant primary producers of the ice-covered marine environment, growing under typically cold, dim conditions. During ice break-up they are released to the water column, where temperatures can be several degrees higher and irradiance can increase by orders of magnitude. To determine how sea ice algae respond to such rapid changes, we carried out incubations to examine their tolerance to environmentally realistic levels of change in temperature and PAR, as expressed by photosynthetic response and production of mycosporine-like amino acids (MAAs). The algae were also exposed to a broader range of temperatures, to evaluate their potential to function in warmer seas in the event, for instance, of anthropogenic transfer to locations further north. When subjected to PAR (0-100μmolm-2s-1) at ecologically relevant temperatures (-1^circC, 2^circC, 5^circC), the algae showed tolerance, indicated by a lack of decline in the quantum efficiency of photosystem II (PSII). The data show that bottom ice algae can tolerate increasing temperature and PAR comparable to the changes experienced during and after sea ice melt. MAA production increased at higher PAR and temperature. At ambient PAR levels, increased temperatures resulted in lower Ï•PSII. However, as PAR levels were increased, higher temperature reduced the level of stress as indicated by higher Ï•PSII values. This result suggests, for the first time in sea ice algal studies, that higher temperatures can ameliorate the negative effects of increased PAR. Exposure to much higher temperatures suggested that the algae were capable of retaining some photosynthetic function at water temperatures well above those currently experienced in some of their Antarctic habitats. However, when temperature was gradually increased past 14^circC, the photosystems started to become inactivated as indicated by a decrease in quantum yield, suggesting that the algae would not be viable if transferred to lower latitude cold temperate areas. â"' 2014 Elsevier B.V.AcknowledgementsWe acknowledge the support from VUW Grant 100241, and FRST Grant VICX0706. MAF permits 2009037596 and 2010040450 were used to transport cultures and samples from Antarctica to New Zealand. We thank Antarctica New Zealand for logistic support in the field. Phil Lester, Kevin Newsham and an anonymous referee are thanked for the advice and critical comments in the development of this manuscript. PC is supported by NERC funding to the BAS Core Programme `Ecosystems.Ì This paper also contributes to the international SCAR research programme `AnT-ERA.Ì Fig. 1 was prepared by Peter Fretwell, BAS. [ST]
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1st AuthorRajanahally, M.AuthorRajanahally, M.Sim, D.Ryan, K.Convey, P.Year2014JournalJournal of Experimental Marine Biology and EcologyVolume461Pages516-527DOI10.1016/j.jembe.2014.10.005URLhttps://www.scopus.com/inward/recor.....4217253493513e2bc4e784361Keywordsalgahigh temperatureirradiancemarine environmentphotosynthesisphotosynthetically active radiationsea icetemperate environmenttemperature effect, Southern Ocean, algae, rank5Author KeywordsElectron transport ratesIce meltPhotophysiologyQuantum efficiency of PSIISea ice
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TypeArticleCitationRajanahally, M., Sim, D., Ryan, K. and Convey, P. (2014) Can bottom ice algae tolerate irradiance and temperature changes?. Journal of Experimental Marine Biology and Ecology, 461: 516-527 doi:10.1016/j.jembe.2014.10.005 IdentifierRajanahally2014Relevancerank5
Convey, P., Can bottom ice algae tolerate irradiance and temperature cha, [Rajanahally2014]. Antarctica NZ, accessed 07/02/2025, https://adam.antarcticanz.govt.nz/nodes/view/63728, 10.1016/j.jembe.2014.10.005