ACTA PHYTOGEOGRAPHICA SUECICA 78 Guest editors: Inger Wallentinus & Pauli Snoeijs Phycological studies of Nordic coastal waters - A festschrift dedicated to Prof. Mats W rern on his 80th birthday - Editor-in-Chief· Erik Sj ogren OPULUS Press AB UPPSALA 1992 Thi volume of Acta Phytogeographica Suecia 'Phycological studies of Nordic coa tal waters' is dedicated to profe or Mat Wremon his 80th birthday, May 28, 1992. The contributors are invited phycologist who are worldng with marine and brackish-water plant in the Nordic countries. The volume ha been financially upported by grant from: Nordiska Kulturfonden, Nordiskt Kollegium fo r Marinbiologi, Goteborgs Marina Forskningscentrum, Stockholms Marina Forskningscentrum, Umea Marina Forskningscentrum, lnstitutionen fo r Systemeko/ogi vid Stockholms Universitet, Waiter och Andree de Nottbecks Stiftelse and Svenska Viixtgeografiska Sallskapet. Grants for printing the colour plates have been received directly by the authors. We are also much indebted for all assistance from the Department of Marine Botany, University of Goteborg. ISBN 91-72 10-078-8 (paperback) ISBN 91-72 1 0-478-3 (cloth) ISSN 0084-59 14 Editor: Erik Sjogren Guest editors: Inger Wallentinus & Pauli Snoeijs Editorial Board: A.W.H. Damman, Storr , CT F.J .A. DanieJs, MUnster L. Ericson, Umea 0. Gj rerevoll, Trondheim D. Glenn-Lewin, Ames, lA 0. Hamann, Copenhagen H. Sjor , Uppsala H. Trass, Tartu Technical editor: Marijke van der Maarel-Ver luy ©Respective author 1992 Drawing of Ceramium tenuicorne on the cover by Pauli Snoeijs Edidit: Svenska Vaxtgeografiska Sallskapet Box 559, S-75 1 22 Uppsala DTP: Opulu Press AB, Upp ala Phototypesetting: Fotosattarna i Uppsala AB Printed in Sweden 1992 by TK i U ppsala AB, U pp ala Acta Phytogeogr. Suec. 78 Contents Preface A tribute to Mats Wc.ern - the nestor of modern Swedish phycology. By lnger Wa llentinus, Marianne Pedersen & Pauli Snoeijs. 5 Ecology and taxonomy of Enteromorpha species in the vicinity of the Forsmark nuclear power plant (Bothnian Sea). By Pauli Snoeijs. 11 Effects of nutrient enrichment on planktic blue-green algae in the Baltic Sea. By Kerstin Wa llstrom, Sif Johansson & UlfLarsson. 25 Studie on the Fucus vesiculosus community in the Baltic Sea. By Hans Kautsky, Lena Kautsky, Nils Kautsky, Ulrik Kautsky & Cecilia Lindblad. 33 Contribution to the seaweed flora of Sweden: New or otherwise interesting records from the west coast. By }an Karlsson, Mats Kuylenstierna & Per Aberg. 49 Colonization and succession of macroalgae on a breakwater in Laholm Bay, a eutrophicated brackish water area (SW Sweden). By To re Wennberg. 65 f Chorda tomentosa Lyngbye in Finnish coastal water . By Guy Hiillors & Kaarina Heikkonen. 79 Primary production of macroalgae in relation to the spectral range and sublittoral light conditions in the Tvarminne archipelago, northern Baltic Sea. By Elina Leskinen, Anita Miikinen, Wilhelm Fortelius, Magnus Lindstrom & Heikki Salemaa. 85 Effects of ferry traffic on the metal content of Fucus vesiculosus in the Aland archipelago, northern Baltic Sea. By Olof Ronnberg, Toro ifO stman & Kaj Adj ers. 95 Floristic aspects of the coastal inlet Inre Verkviken, northern Aland. By Hans Mathiesen & Lisbeth Mathiesen. 101 Marine algae south of the island Vejrp, the Sam p area, Denmark. By Ruth Nielsen & Karsten DahL 111 Changes in fucoid distributions and abundances in the inner Oslofjord, Norway: 1974-80 versus 1988-90. By To r L. Bokn, Steven N. Murray, Frithjof E. Moy & Jan B. Magnusson. 117 Field and culture observations on Uronema curvatum Printz (Chlorophyta). By Jan Rueness. 125 The gradient of the benthic algal vegetation along the eastern Icelandic coast. By lvka M. Munda. 131 Acta Phytogeogr. Suec. 78 A tribute to Mats Wcern Mats Wcern. A tribute to Mats W cern - the nestor of modern Swedish phycology Inger Wa llentinus1, Marianne Pedersen2 & Pauli Snoeijs3 1 Department of Marine Botany, University of Goteborg, Carl Skottsbergs gata 22, S-413 19 Goteborg, Sweden; 2Department of Physiological Botany, Uppsala University, Box 540, S-751 21 Uppsala, Sweden; 3DepartmentofEcological Botany, Uppsala University, Box 559, S-751 22 Uppsala, Sweden. For centuries, Swedish scientists have studied the taxonomy professors G. Einar Du Rietz and Rutger Sernander, was and biology of algae. C. von Linne included already in the awarded the highest degree at the University ofUppsala and 18th century algae in his studies. He was followed by made him famous all over the world. It became the classic famous algologists such as C. A. Agardh, his son J. G. work for quotations on the Baltic algae and their ecology. Agardh, J. E. Areschoug, F. R. Kj ellman, N. Svedelius, C. Mats was not only inspired by his predecessors; his Skottsberg and H. Kylin. When Mats Wrern started his greatest inspiration has always been the sea. Together with studies on algae, and also on brackish water phanerogams his family and friends he made many summer excursions to in the late 1920s, he was certainly inspired by the works of the archipelago of Oregrund, an area which is through his those famous phycologists. Some of them were his tutors, as thesis now well known to marine scientists all over the he has pointed out in the preface to his doctoral thesis world. In the preface to the thesis he described how his (Wrern 1952). This thesis, prepared at the Department of mother performed the difficult task of navigating in these Ecological Botany (Yaxtbiologiska institutionen) under tricky waters, with many rocks hidden just below the water Acta Phytogeogr. Suec. 78 6 I. Wa llentinus et al. surface. Stina Wrern,his wife, played the important role of camped on the islands during the diving periods; the list of secretary and dive watcher when Mats examined the flora provisions included hard bread, butter, salt, bacon, eggs, several fathoms under the surface. In 193 8 Mats W rem herring, cocoa, milkpowder, beer and Swedish canned tarted to dive in order to study the algae down on the sea­ 'blodpudding' (blackpudding). Unfortunately, because of bed. Scientific diving was a rather new method to study the World War 11 Mats was not able to fulfil his aim to study the marine environment. Earlier, Gislen (1929-30) had used a algal vegetation across the Baltic Sea, to determine the hired diver and made ome dives himself, in order to study influence of the gradient in alinity on pecies distribution the hard-bottom communities of the Gullmar Fj ord at the and to compare the ecology of the algae on the easternand Swedish west coast. Previously dredging wa used to collect western side of the Baltic Sea. algae from the sublittoral. This method had the drawback To be able to photograph the algae, Mats designed a that algae from different levels were mixed, which made it special housing for his Rolliflex camera, which was built by impossible to determine the depth interval along which John Ambertsson at the In titute of Chemistry, University different algal species occur. Neither could any quantitative of Upp ala. This enabled him to adjust the distance and measures be obtained. wind the film after the camera hou ing was screwed down Mats wanted to know the exact position of these upper with 16 winged nuts. The time and aperture had to be et in and lower limits of species distribution and how they vary advance. A Sixtus light meter was kept in a preserving-jar. with salinity. He soon came to the conclusion that scientific Mats reported aperture and time to the boat, where the precision could only be reached by using a diving suit, and camera was prepared and lowered down to him, and then he by documertting the vegetation through photography and waited until the light meter gave the same values as before. verbal comments over a telephone. In those days one had to When the diver found an interesting and suitable place he use a heavy suit; the aqualung of Costeau and Gagnan was ordered "Weight down" and determined the depth. He then not invented until 1943. Dr. Hans Hass, the famous diver made a general survey of the ea-bed and all vegetation in and photographer, took his first under-water photos in Dal­ sight, usually to a distance of 2-8 m, and estimated the matia in the same year as Mats did in Sweden, 1938. degree of cover of the different algal species on a 1-5 scale. The expenses during the first year of the project were A frame was placed on the rock and Mats reported the cover covered by Mats' father. Certainly, the University was values by telephone to the record-keeper in the boat. Then, interested in the work, but Mats preferred not to ask for a all algae within the frame were scraped off from the surface grant, as he did not want to be compelled to continue diving and collected in a bag, which was sent up and numbered for if he found it too hard. His mother was also intere ted in the further analyses in the laboratory. project; she insisted on making one of the first dives, just to Apparently, the record-keepers have bowdlerized his re­ see that it was not too dangerous for her son. ports from the sea bottom, with the exception of Stina The diving suit was a German double suit, which Mats Wrern, who wrote down everything Mats said. The diving preferred because it allowed him to crawl safely on his reports provide evidence of his devotion and enthusiasm for knees while scraping off the algal vegetation. The alterna­ this task. One of us (M. P.) had the privilege to read the tive was the English suit, which had lead weights suspended diving reports and compare them with the precise cientific from the chest.