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Author Bischof, K; Peralta, G; Kräbs, G; van de Poll, WH; Perez-Llorens, JL; Breeman, AM
Title Effects of solar UV-B radiation on canopy structure of Ulva communities from southern Spain Type Journal Article
Year 2002 Publication Journal of Experimental Botany Abbreviated Journal J Exp Bot
Volume 53 Issue 379 Pages (down) 2411-2421
Keywords canopy formation; photosynthesis; ultraviolet radiation; Ulva rotundata
Abstract Within the sheltered creeks of Cádiz bay, Ulva thalli form extended mat-like canopies. The effect of solar ultraviolet radiation on photosynthetic activity, the composition of photosynthetic and xanthophyll cycle pigments, and the amount of RubisCO, chaperonin 60 (CPN 60), and the induction of DNA damage in Ulva aff. rotundata Bliding from southern Spain was assessed in the field. Samples collected from the natural community were covered by screening filters, generating different radiation conditions. During daily cycles, individual thalli showed photoinhibitory effects of the natural solar radiation. This inhibition was ev

en more pronounced in samples only exposed to photosynthetically active radiation (PAR). Strongly increased heat dissipation in these samples indicated the activity of regulatory mechanisms involved in dynamic photoinhibition. Adverse effects of UV-B radiation on photosynthesis were only observed in combination with high levels of PAR, indicating the synergistic effects of the two wavelength ranges. In samples exposed either to PAR+UV-A or to UV-B+UV-A without PAR, no inhibition of photosynthetic quantum yield was found in the course of the day. At the natural site, the top layer of the mat-like canopies is generally completely bleached. Artificially designed Ulva canopies exhibited fast bleaching of the top layer under the natural solar radiation conditions, while this was not observed in canopies either shielded from UV or from PAR. The bleached first layer of the canopies acts as a selective UV-B filter, and thus prevents subcanopy thalli from exposure to harmful radiation. This was confirmed by the diff

erences in photosynthetic activity, pigment composition, and the concentration of RubisCO in thalli with different positions within the canopy. In addition, the induction of the stress protein CPN 60 under UV exposure and the low accumulation of DNA damage indicate the presence of physiological protection mechanisms against harmful UV-B. A mechanism of UV-B-induced inhibition of photosynthesis under field conditions is proposed.
Address
Corporate Author Thesis
Publisher Oxford University Press Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area southern Spain Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 12
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Author Schleser, GH; Jayasekera, R
Title δ13C-variations of leaves in forests as an indication of reassimilated CO2 from the soil Type Journal Article
Year 1985 Publication Oecologia Abbreviated Journal Oecologia
Volume 65 Issue Pages (down) 536-542
Keywords soil respiration; photosynthesis; vascular plant
Abstract
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ ms Serial 11
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Author Thomas, DN; Dieckmann, GS (eds)
Title Sea ice – an introduction to its physics, chemistry, biology and geology Type Book Whole
Year 2003 Publication Abbreviated Journal
Volume Issue Pages (down) 402 pp
Keywords Sea Ice
Abstract Sea ice, which covers up to 7% of the planet's surface, is a major component of the world's oceans, partly driving ocean circulation and global climate patterns. It provides a habitat for a rich diversity of marine organisms, and is a valuable source of information in studies of global climate change and the evolution of present day life forms. Increasingly, sea ice is being used as a proxy for extraterrestrial ice covered systems.

Sea Ice provides a comprehensive review of our current available knowledge of polar pack ice, the study of which is severely constrained by the logistic difficulties of working in such harsh and remote regions of th

e earth. The book's editors, Drs Thomas and Dieckmann have drawn together an impressive group of international contributing authors, providing a well-edited and integrated volume, which will stand for many years as the standard work on the subject. Contents of the book include details of the growth, microstructure and properties of sea ice, large-scale variations in thickness and characteristics, its primary production, micro-and macrobiology, sea ice as a habitat for birds and mammals, sea ice biogeochemistry, particulate flux, and the distribution and significance of palaeo sea ice.
Address Thomas: School of Ocean Sciences, University of Wales, Bangor, UK; Dieckmann: Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany
Corporate Author Thesis
Publisher Blackwell Science Ltd Place of Publication Oxford Editor Thomas, DN; Dieckmann, GS
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN 0-632-05808-0 Medium
Area Expedition Conference
Notes 40 Illustrations Approved yes
Call Number refbase @ user @ library-34/436/1 Serial 7
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Author de Castellvi, J (ed)
Title Actas des tercer symposium espanol de estudios Antarcticos. Gredos, 3 al 5 de octubre de 1989 Type Book Whole
Year 1990 Publication Abbreviated Journal
Volume Issue Pages (down) 379 pp
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Publisher Comision interministerial de Cienctia y Technologia Place of Publication Madrid Editor de Castellvi, J
Language Spanish Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ library-32/19/20 Serial 9
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Author Lohrmann, A; Cabrera, R; Kraus, NC
Title Acoustic-doppler velocimeter (ADV) for laboratory use Type Journal Article
Year 1994 Publication Fundamentals and advancements in hydraulic measurements and experimentation. Proceedings, Hydraulic Division/ASCE, August 1994 Abbreviated Journal
Volume Issue Pages (down) 351-365
Keywords methods; flow; flume
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference Symposium on fundamentals and advancements in hydraulic measurements and experimentation
Notes Approved no
Call Number refbase @ user @ Serial 8
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