571 2008 The Antarctic ecosystem of Potter Cove, King-George Island (Isla 25 de Mayo) Synopsis of research performed 1999-2006 at the Dallmann Laboratory and Jubany Station _______________________________________________ Edited by Christian Wiencke, Gustavo A. Ferreyra, Doris Abele and Sergio Marenssi ALFRED-WEGENER-INSTITUT FÜR POLAR- UND MEERESFORSCHUNG In der Helmholtz-Gemeinschaft D-27570 BREMERHAVEN Bundesrepublik Deutschland ISSN 1866-3192 Hinweis Notice Die Berichte zur Polar- und Meeresforschung The Reports on Polar and Marine Research are issued werden vom Alfred-Wegener-Institut für Polar-und by the Alfred Wegener Institute for Polar and Marine Meeresforschung in Bremerhaven* in Research in Bremerhaven*, Federal Republic of unregelmäßiger Abfolge herausgegeben. Germany. They appear in irregular intervals. 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Since 2008 the "Reports on Polar and Marine Research" (ISSN 1866-3192) are only available as web based open-access-publications (URL: http://epic.awi.de) The Antarctic ecosystem of Potter Cove, King-George Island (Isla 25 de Mayo) Synopsis of research performed 1999-2006 at the Dallmann Laboratory and Jubany Station _______________________________________________ Edited by Christian Wiencke, Gustavo A. Ferreyra, Doris Abele and Sergio Marenssi Please cite or link this item using the identifier hdl: 10013/epic.30038 or http://hdl.handle.net/10013/epic.30038 ISSN 1866-3192 Editors: Christian Wiencke1, Gustavo A. Ferreyra2, Doris Abele1, & Sergio Marenssi2 1 Alfred Wegener Institute for Polar and Marine Research, D-27570 Bremerhaven, Germany 2 Instituto Antártico Argentino, Cerrito 1248, 1010 Buenos Aires, Argentina TABLE OF CONTENTS INTRODUCTION………………………………………………………………… 7 1. THE ENVIRONMENT OF POTTER COVE A. Richter, S. Wuttke & K. Zacher: Two years of in situ UV measurements at the Dallmann Laboratory/ Jubany Station................................................................................................ 12 S. Kraus & R. del Valle: Geology, tectonics and Ar-Ar ages of the magmatic dykes from Potter Peninsula (King George Island, South Shetland Islands)…………………….. 20 E. Ermolin, A.S. Busso: Interaction between permafrost and groundwater on the Potter Peninsula, King George Island (Isla 25 de Mayo), Antarctic Peninsula region………….. 31 D. Abele, A. Atencio, D. Dick, O. Gonzalez, M. Kriews, S. Meyer, E. Philipp &V.I. Stölting: Iron, copper and manganese discharge from glacial melting into Potter Cove and metal concentrations in Laternula elliptica shells………………….. 39 G.A. Ferreyra, I.R. Schloss, G. Mercuri, L. Ferreyra & K.-U. Richter: The potential ecological significance of dissolved and particulate matter in the water column of Potter Cove, King George Island (Isla 25 de Mayo), South Shetland Islands………………………………………………………….... 47 2. STRUCTURE AND FUNCTION OF THE ECOSYSTEM M.L. Quartino H. Zaixso & A. Boraso de Zaixso: Macroalgal assemblages related to abiotic factors in Potter Cove, King George Island (Isla 25 de Mayo), Antarctica………………………………….... 58 M.L. Quartino, A. Boraso de Zaixso & F.R. Momo: Macroalgal production and the energy cycle of Potter Cove…………………. 68 V.L. Fuentes, S.B. Schnack-Schiel, I.R. Schloss & G.G. Esnal: Mesozooplankton of Potter Cove: Community composition and seasonal distribution in 2002 and 2003…………………………………………………….. 75 M.S. Hoffmeyer & V.L. Fuentes: Morphometry of Calanoides acutus and Calanus propinquus (Copepoda, Calanoida) from West Antarctic Peninsula waters…………………………….. 85 1 E. Barrera-Oro & R. Casaux: General ecology of coastal fish from the South Shetland Islands and West Antarctic Peninsula areas………………………………………………………… 95 G. Mercuri, M. Tatián, F.R. Momo, V.L. Fuentes & R. Sahade: Massive input of terrigenous sediment into Potter Cove during austral summer and the effects on the bivalve Laternula elliptica: a laboratory experiment…………………………………………………………………………. 111 M. Tatián, G. Mercuri, V.L. Fuentes, J.C. Antacli, A. Stellfeldt & R. Sahade: Role of benthic filter feeders in the pelago-benthic coupling: assimilation, biodeposition and particle flux………………………………………………….... 118 M. Tatián, C. Milozzi, R. Sahade, G. Mercuri & C. Lagger: Contribution of different seston components to ascidian food in Potter Cove……………………………………………………………………..…. 128 G. Veit-Köhler, J.C. Antacli & A. Rose: Metazoan meiofauna in Potter Cove, King George Island………………..….. 135 N. Wilbert: Species composition and structure of the ciliate community in the benthos at King George Island, Antarctica ………………………………………………… 141 M. Graeve, R. Sahade, V.L. Fuentes, M. Tatián & G. Kattner: Bentho-pelagic coupling at Potter Cove, Antarctica: A fatty acid approach... 147 A.G. Atencio, M.L. Bertolin, L. Longhi, G.A. Ferreyra, M.E. Ferrario & I.R. Schloss: Spatial and temporal variability of chlorophyll-a and particulate organic matter in the sediments and the water column of Potter Cove, Antarctica… 154 F.R. Momo, R. Sahade & M. Tatián: Benthic animal communities of Potter Cove (King George Island, Antarctica): Observed patterns and explanatory models…………………….. 162 C. Büßer, S. Hahn, A. Gladbach, S. Lorenz, A. Nordt, P. Quillfeldt, T. Schmoll & H.-U. Peter: A decade of fundamental ecological research on storm-petrels at the Tres Hermanos colony, Potter Peninsula, King George Island……………………. 168 R. Casaux & E. Barrera-Oro: Recent studies on the Antarctic Shag Phalacrocorax bransfieldensis …… 176 A.M. Stchigel, M. Calduch, W.P. Mac Cormack & J. Guarro: Micromycetes from King George Island , South Shetland Islands, Antarctica ………………………………………………………………………… 184 2 3. ECOPHYSIOLOGY OF KEY ORGANISMS IN THE ECOSYSTEM C. Lütz, M. Blassnigg & D. Remias: Different flavonoid patterns in Deschampsia antarctica and Colobanthus quitensis from the maritime Antarctic …………………………………………... 192 F. Laturnus, P. Sandén, T. Svensson & C. Wiencke: Finding the scattered pieces of the mechanisms behind the formation of volatile halogen-containing C1- and C2-compounds in Antarctic macroalgae ……………………………………………………………………….. 200 G. Malanga, P.M. Gonzalez, M.S. Estevez, D. Abele & S. Puntarulo: Oxidative stress in Antarctic algae and molluscs ……………………………. 208 E. Philipp, T.Brey, M. Voigt & D.Abele: Growth and age of L. elliptica populations in Potter Cove, King George Island ……………………………………………………………………………… 216 S.C. Vazquez, S.H. Coria & W.P. Mac Cormack: Properties of extracellular proteases produced by psychrotolerant bacteria isolated in the vicinities of Jubany station ……………………………………... 223 4. RESPONSE OF KEY ORGANISMS TO GLOBAL AND REGIONAL CHANGES AND ECOSYSTEM FUNCTIONING G.A. Ferreyra, W.P. Mac Cormack, M. Hernando, E. Hernandez, I.R. Schloss, D. Abele & G. Malanga: A synthesis on UVR biological effects research in the water column of Potter Cove ……………………………………………………………………….. 234 M. Hernando, G. Malanga, S. Puntarulo & G.A. Ferreyra: A comparative study of defence strategies against UV-induced damage in an Antarctic diatom (Thalassiosira sp.) and a Sub-Antarctic phyto- flagellate (Asteromonas sp.) ……………………………………………………. 243 M.Y. Roleda, K. Zacher, G.L. Campana, A. Wulff, D. Hanelt, M.L. Quartino & C. Wiencke: Photosynthetic performance and impact of ultraviolet radiation on the reproductive cells of Antarctic macroalgae …………………………………..... 254 R. Rautenberger & K. Bischof: UV susceptibility of photosynthesis of adult sporophytes of four brown Antarctic macroalgae (Phaeophyceae) ………………………………………… 263 U. Karsten, K. Hoyer & C. Wiencke: Interactive effects of temperature and radiation on UV-absorbing myco- sporine-like amino acids in two red macroalgae from Antarctica …………… 270 3 G.L. Campana, F.R. Momo, M.L. Quartino & G.A. Ferreyra: Effects of UV radiation and grazing on biomass and primary production of subtidal benthic algae in Antarctica ………………………………………… 278 K. Zacher & G.L. Campana: UV and grazing effects on an intertidal and subtidal algal assemblage: a comparative study ………………………………………………….……………. 287 A. Wulff & K. Zacher: Short-term UV effects on the photosynthesis of Antarctic benthic diatoms…..295 G.L. Campana, M.L. Quartino, A. Yousif & A. Wulff: Impacts of UV radiation and grazing on the structure of a subtidal benthic diatom assemblage in Antarctica