The Role of Freshwater Outflow in Coastal Marine Ecosystems NATO ASI Series Advanced Science Institutes Series A series presenting the results of activities sponsored by the NATO Science Committee, which aims at the dissemination of advanced scientific and technological knowledge, with a view to strengthening links between scientific communities. The Series is published by an international board of publishers in conjunction with the NATO Scientific Affairs Division A Life Sciences Plenum Publishing Corporation B Physics London and New York C Mathematical and D. Reidel Publishing Company Physical Sciences Dordrecht, Boston and Lancaster D Behavioural and Martinus Nijhoff Publishers Social Sciences Boston, The Hague, Dordrecht and Lancaster E Applied Sciences F Computer and Springer-Verlag Systems Sciences Berlin Heidelberg New York Tokyo G Ecological Sciences Series G: Ecological Sciences Vol. 7 The Role of Freshwater Outflow in Coastal Marine Ecosystems Edited by Stig Skreslet Nordland College, PO. Box 6003, 8016 M0rkved, Bod0 Norway Springer-Verlag Berlin Heidelberg New York Tokyo Published in cooperation with NATO Scientific Affairs Division Proceedings of the NATO Advanced Research Workshop on The Role of Freshwater Outflow in Coastal Marine Ecosystems held in BQd0, Norway, May 21-25, 1985 ISBN-13: 978-3-642-70888-6 e-ISBN-13: 978-3-642-70886-2 001: 10.1007/978-3-642-70886-2 Library of Congress Cataloging in Publication Data. NATO Advanced Research Workshop on the Role of Freshwater Outflow in Coastal Marine Ecosystems (1985 : Bode!, Norway) The role of freshwater outflow in coastal marine ecosystems. (NATO ASI series. Series G, Ecological sciences; v. 7). Includes index. 1. Marine ecology-Congresses. 2. Coastal ecology-Congresses. 3. Stream ecology-Congresses.1. Skreslet, Stig, 1940-. II. Title. III. Title: Freshwater outflow in coastal marine ecosystems. IV. Series: NATO ASI series. Series G, Ecological sciences; no. 7. QH541.5.S3N371985 575.5'2636 86-6438 ISBN-13:978-3-642-70888-6 (U.S.) This work is subjectto copyright. All rights are reserved, whether the whole or part ofihe material is concerned, specifically those of translating, reprinting, re-use of illustrations, broadcastings, reproduction by photocopying machine or similar means, and storage in data banks. Under § 54 of the German Copyright Law where copies are made for other than private use, a fee is payable to 'Verwertungsgesellschaft Wort", Munich. © Springer-Verlag Berlin Heidelberg 1986 Softcover reprint of the hardcover 1st edition 1986 2131/3140-543210 PREFACE Over the last decade or two marine scientists have become more aware of the role of freshwater outflow in coastal waters. Some have raised the question whether or not regulation of river flow may change the biological productivity in coastal marine ecosystems. The idea of organising a workshop to deal with this problem, arose from parallel concern in Norway and Canada, but it was soon recognised that the scientific interests were also shared by research groups in other countries. After the initial contacts had been made, it was agreed to establish a committee which should assist the workshop director in organising the workshop. The Organising committee consisted of K.F. Drinkwater, Bedford Institute of Oceanography, Canada; S. Skreslet (workshop director), Nordland College, Norway; V.S. Smetacek, Institut fur Meereskunde an der Universitat Kiel, Germany; and H. Svendsen, University of Bergen, Norway. An Advisory committee was established to provide terms of reference for the Organising committee, with regard to the programme and selection of participants. This committee con sisted of J.B.L. Matthews (chairman), Scottish Marine Bio logical Association, U.K.; T.R. Parsons, University of British Columbia, Canada; R. S~tre, Institute of Marine Research, Nor way; M.M. Sinclair, Fisheries and Oceans, Canada; and W.S. Wooster, University of Washington, Canada. The workshop was organised to fit the requirements of an Ad vanced Research Workshop funded by the NATO Scientific Affairs Division, which eventually awarded a grant to cover the major part of the expences. However, additional financial support was granted by the Norwegian Fisheries Research Council and the Nordland College Fisheries Fund. VI Several colleagues at the Nordland College, both among the administrative and scientific staffs, eventually became in volved in one way or the other, and contributed significantly to the success of the workshop. In particular, I am indebted to Ewa Bivand whose professional support, skill and patience was a true relief. I want to thank all those who have been involved in the work shop, not least the participants whose enthusiasm lifted the programme from scetches on paper to a fruitful reality which points to promising scientific endeavors in the future. Bod0, 13 November 1985 Stig Skreslet CONTENTS OPENING ADDRESS A. Sandberg INVITED CONTRIBUTIONS Freshwater outflow in relation to space and time dimensions of complex ecological interactions in coastal waters 3 S. Skreslet Mixing and exchange processes in estuaries, fjords and shelf waters 13 H. Svendsen The role of brackish plumes in open shelf waters 47 R.W. Garvine Laboratory modeling of dynamic processes in fjords and shelf waters 67 T.A. McClimans Impact of freshwater discharge on production and transfer of materials in the marine environment 85 V.S. Smetacek A framework for discussion of marine zooplankton production in relation to freshwater runoff 107 J.B.L. Matthews The dependence of fish larval survival on food and VIII predator densities 117 W.C.Leggett Assessment of effects of freshwater runoff varia bility on fisheries production in coastal waters 139 M. Sinclair, G.L. Bugden, C.L. Tang, J.-C. Therriault and P.A. Yeats computer model analysis of pelagic ecosystems in estuarine waters 161 T. Parsons and T.A. Kessler INSHORE WATERS The capacity of Lake Melville fjord to store run off 183 S.A. Akenhead and J. Bobbitt Inorganic nutrient regeneration in Loch Etive bottom water 195 A. Edwards and B.E. Grantham Physical exchange and the dynamics of phyto- plankton in Scottish sea-lochs 205 P. Tett Freshwater outflow effects in a coastal, macro tidal ecosystem as revealed by hydrological, chemical and biological variabilities (Bay of Brest, western Europe) 219 B. Queguiner and P. Treguer MARGINAL SEAS River input of nutrients into the German Bight 231 U.H. Brockmann and K. Eberlein IX Effects of freshwater inflow on the distribution, composition and production of - plankton in the Dutch coastal waters of the North Sea 241 H.G. Fransz Freshwater runoff control of the spatio-temporal distribution of phytoplankton in the lower st. Lawrence Estuary (Canada) 251 J.-C. Therriault and M. Levasseur Biological and physical characteristics of a frontal region associated with the arrival of spring freshwater discharge in the southwestern Gulf of st. Lawrence 261 B. Cote, M. EI-Sabh and R. de la Durantaye SHELF WATERS Relationships of st. Lawrence River outflow with sea surface temperature and salinity in the north west Atlantic 271 J.A. Koslow, R.H. Loucks, K.R. Thompson and R.W. Trites Water retention over Flemish Cap 283 S.A. Akenhead The Scottish Coastal Current 295 J.H. Simpson and A.E. Hill Runoff driven coastal flow off British Columbia 309 P.H. LeBlond, B.M. Hickey and R.E. Thomson The seasonal influence of Chesapeake Bay phyto- plankton to the continental shelf 319 H.G. Marshall x River runoff and shrimp abundance in a tropical coastal ecosystem - the example of the Sofala Bank (central Mozambique) 329 A.J. da Silva Timing and duration of spring blooming south and southwest of Iceland 345 T. Thordardottir Production, grazing and sedimentation in the Norwegian Coastal Current 361 R. Peinert Advection of Calanus finmarchicus between habitats in Norwegian coastal waters 375 S. Skreslet and N.A. R0d The ecological impact of the East Greenland Current on the north Icelandic waters 389 S.A. Malmberg GROUP REPORTS Oceanographic functions of freshwater discharge and consequences of change 405 Interdisciplinary assessment of ecological problems related to freshwater outflow in coastal marine systems 417 SUMMARY CONTRIBUTION On the role of freshwater outflow on coastal marine ecosystems - a workshop summary 429 K.F. Drinkwater