The Biology and Management of the River Dee
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THEBIOLOGY AND MANAGEMENT OFTHE RIVERDEE INSTITUTEofTERRESTRIAL ECOLOGY NATURALENVIRONMENT RESEARCH COUNCIL á Natural Environment Research Council INSTITUTE OF TERRESTRIAL ECOLOGY The biology and management of the River Dee Edited by DAVID JENKINS Banchory Research Station Hill of Brathens, Glassel BANCHORY Kincardineshire 2 Printed in Great Britain by The Lavenham Press Ltd, Lavenham, Suffolk NERC Copyright 1985 Published in 1985 by Institute of Terrestrial Ecology Administrative Headquarters Monks Wood Experimental Station Abbots Ripton HUNTINGDON PE17 2LS BRITISH LIBRARY CATALOGUING-IN-PUBLICATIONDATA The biology and management of the River Dee.—(ITE symposium, ISSN 0263-8614; no. 14) 1. Stream ecology—Scotland—Dee River 2. Dee, River (Grampian) I. Jenkins, D. (David), 1926– II. Institute of Terrestrial Ecology Ill. Series 574.526323'094124 OH141 ISBN 0 904282 88 0 COVER ILLUSTRATION River Dee west from Invercauld, with the high corries and plateau of 1196 m (3924 ft) Beinn a'Bhuird in the background marking the watershed boundary (Photograph N Picozzi) The centre pages illustrate part of Grampian Region showing the water shed of the River Dee. Acknowledgements All the papers were typed by Mrs L M Burnett and Mrs E J P Allen, ITE Banchory. Considerable help during the symposium was received from Dr N G Bayfield, Mr J W H Conroy and Mr A D Littlejohn. Mrs L M Burnett and Mrs J Jenkins helped with the organization of the symposium. Mrs J King checked all the references and Mrs P A Ward helped with the final editing and proof reading. The photographs were selected by Mr N Picozzi. The symposium was planned by a steering committee composed of Dr D Jenkins (ITE), Dr P S Maitland (ITE), Mr W M Shearer (DAES) and Mr J A Forster (NCC). The Institute of Terrestrial Ecology (ITE) was established in 1973, from the former Nature Conservancy's research stations and staff, joined later by the Institute of Tree Biology and the Culture Centre of Algae and Protozoa. ITE contributes to, and draws upon, the collective knowledge of the 13 sister institutes which make up the Natural Environment Research Council, spanning all the environmental sciences. The Institute studies the factors determining the structure, composition and processes of land and freshwater systems, and of individual plant and animal species. It is developing a sounder scientific basis for predicting and modelling environmental trends arising from natural or man-made change. The results of this research are available to those responsible for the protection, management and wise use of our natural resources. One quarter of ITE's work is research commissioned by customers, such as the Department of Environment, the European Economic Community, the Nature Conservancy Council and the Overseas Development Administration. The remainder is fundamental research supported by NERC. ITE's expertise is widely used by international organizations in overseas projects and programmes of research. Dr D Jenkins Institute of Terrestrial Ecology Banchory Research Station Hill of Brathens, Glassel BANCHORY Kincardineshire AB3 4BY 033 02 (Banchory) 3434 3 Contents Preface 5 The physical background of the River Dee 7 (Judith K Maize Is, Dept of Geography, University of Aberdeen) Hydrology of the River Dee and its tributaries 23 (J S Warren, North East River Purification Board, Aberdeen) Land use within the catchment of the River Dee 29 (J S Smith, Dept of Geography, University of Aberdeen) The chemistry of the river system 34 (K B Pugh, North East River Purification Board, Aberdeen) Vegetation of the River Dee 42 (N T H Holmes, Nature Conservancy Council, Peterborough) Vegetation of the valley floor of the River Dee 56 (J A Forster and Jacqui Green, Nature Conservancy Council, Aberdeen) Invertebrates of the River Dee 64 (M B Davidson*, R P Owen* and M R Youngt, *North East River Purification Board, Aberdeen, tDept of Zoology, University of Aberdeen) Vertebrates, except salmon and trout, associated with the River Dee 83 (D Jenkins* and M V Be Ilt, *Institute of Terrestrial Ecology, Banchory, tlnstitute of Marine Biochemistry, Aberdeen) Agricultural land use beside the River Dee 94 (H L Black, North of Scotland College of Agriculture, Aberdeen) Forestry beside the River Dee 100 (H G Miller* and G Tuleyt, *Dept of Forestry, University of Aberdeen, tForestry Commission, Banchory) River engineering and the control of erosion 105 (B B Willetts, Dept of Engineering, University of Aberdeen) Water abstraction from the River Dee 111 (I D Brown, Dept of Water Services, Grampian Regional Council) Fishery management on the River Dee 117 (J Oswald, Glen Tanar Estates, Aboyne) Amenity and recreation on the River Dee 121 (R D Watson, North East Mountain Trust, Aberdeen) Salmon catch statistics for the River Dee, 1952-83 127 (W M Shearer, Dept of Agriculture & Fisheries for Scotland, Montrose) The status of the River Dee in a national and international context 142 (P S Maitland, Institute of Terrestrial Ecology, Edinburgh) Concluding comments 149 (C H Gimingham, Dept of Plant Science, University of Aberdeen) 4 Appendix I: List of participants 152 Appendix ll: List of plant and animal species referred to in the text 154 5 Preface The aims of this symposium were to describe different earlier ploughing after the harvest. In the mid-reaches, interests in the River Dee, to assess existing knowl- a great extent is forested by both private estates and edge, to identify gaps in knowledge and to determine the Forestry Commission, and the upper valley is one whether there are conflicts between the different of the most densely wooded parts of Britain. interests and, if so, ways of reconciling them. The river is of value to geographers, at least partly Many people are interested in the River Dee. It is because the course and the banks have been little widely known as one of the more beautiful parts of disturbed. The purity of its water typifies highland eastern Scotland attracting many tourists each year. streams running over granite, and, to the ecologist, the The strong associations of the valley with Royalty have Dee is an excellent example of a nutrient-poor river given it the name 'Royal Deeside'. Recently, many with little ecological change from source to mouth. new people have come to make their homes in These features make the river and its associated Deeside, not only because of its accessibility to tributaries and lochs of considerable interest to natural Aberdeen, but because it is a lovely place in which to scientists, and several wildlife species found on and by live. Scenic beauty adds therefore to the local econ- the waterways are important to conservationists. This omy, with the river as the focus of the main valley. scientific interest is not merely academic, but is shared by a large and ever-growing number of amateur The river is also important as a source of drinking naturalists who not only watch birds, but also study water, as it is very largely free of pollution; it supplies the flowers, butterflies, moths and the interesting wild the city of Aberdeen, as well as villages in the valley. mammals of the area. At least until recently, the Dee has been one of the most important salmon rivers in northern Scotland The expansion in the human population at the Aber- and, through salmon fishing, it makes an essential deen end of the valley and increased wealth have contribution to the local economy. It has been carefully given rise to new water-based recreational activities, managed as a salmon fishery for over 100 years, and including water ski-ing, canoeing, wind-surfing and, recent decreases in numbers of fish caught by rod and most recently, skin-diving. These activities, together line, together with the threats of increased abstraction with walking and picnicking, and camping where this is of water from the river, are a cause of concern to permitted by the landowners, put pressure on the people interested in the fishery. banks of the river. All these interests and activities testify to the importance of the river system; and the However, tourism and the salmon fishery are not the symposium reflected a need to discuss whether future only important contributors to the local economy. management of the area needs greater liaison and Agriculture, forestry, and other sport are also impor- co-ordination to ensure that conflict is avoided and tant interests affecting the river. Farmers graze their developments agreed, and that the river as a whole is stock adjacent to the river and are responsible for the wisely managed. farming practices which determine the chemistry of the water running off their land. Under the influence of David Jenkins price differences and subsidy, agriculture is changing, Hill of Brathens with fewer cattle, more grain, new crops, and ever July 1985 á 7 The physical background of the River Dee JUDITH K MAIZELS Department of Geography, University of Aberdeen 1 Introduction 2.2 Development of the drainage network This paper examines the physical background to the During the Mesozoic era, the Grampians are believed Dee and its catchment from 4 approaches: (i) the to have been mantled by a series of sedimentary cover major geomorphic characteristics of the catchment, rocks (Bremner 1942), and to have been uplifted including its solid geology and topography, the de- several times during the Tertiary period. Each period of velopment of the drainage network, its glacial history uplift generated a new 'cycle of erosion' such that the and associated glacial and fluvioglacial deposits; (ii) the Grampians were subjected to extensive sub-aerial nature of the bank and bed materials, and the weathering to produce a succession of peneplaned longitudinal profile of the river; (iii) the development of erosion surfaces, with residual granite mountain meanders, bars and islands in the river; (iv) some ridges, or summits forming the monadnock level of the evidence for channel changes since the mid-19th Cairngorm plateau (Johnstone 1966; Sissons 1967).