Ritchie, W. and Mather, A.S. (1984). The beaches of Scotland. Commissioned by theCountryside Commission for Scotland 1984. Reprinted 2005 by Scottish Natural Heritage asCommissioned Report No. 109.
This report, or any part of it, should not be reproduced without the permission of Scottish Natural Heritage.This permission will not be withheld unreasonably. The views expressed by the author(s) of this report shouldnot be taken as the views and policies of Scottish Natural Heritage. Please note that all statistics, lists ofSites of Special Scientific Interest, etc are given in the appendix in the project report and some of them mayhave changed.
Beginning in 1969 and ending in 1981, all the sand beaches of Scotland, along with their associateddunes, links and machair areas (thereafter referred to as a beach unit or beach complex), were surveyed forthe Countryside Commission for Scotland. Eighteen regional reports were published, and their boundaries,along with dates of completion, are shown in the accompanying outline map.
Each survey consisted of a physical inventory of the location, dimensions, morphology, materials, vegetationand land use of the beach complex areas. Additional information was recorded on ownership and access.Particular attention was paid to those aspects of the environment that related to recreation and amenity.Wherever possible, some account was given of trends in physical stability as could be deduced during thebrief period of fieldwork. The effects of the current types and levels of use were also assessed. The minimumsize of beach unit was set arbitrarily at a coastal length of 100m. For some of the vast beach and duneareas such as occur in parts of Scotland, subdivision into more manageable units was necessary. In total,647 units were surveyed. With the completion of the surveys of the 466 beach units in the Highlands andIslands, a comprehensive report (The Beaches of the Highlands and Islands) was published in 1977. From1978–1981, the remaining beaches of Lowland Scotland were surveyed.
This report on the beach complexes of both the Highlands and Islands and Lowland beach units is dividedinto two main sections which correspond to the remit of the sponsoring body, the Countryside Commissionfor Scotland. These are the distribution and physical characteristics of the beach and associated blown sandsurfaces, as well as the background factors that have created the resource, and the utilisation of these areas,with special emphasis on the discussion of environmental impacts, accessibility and value for recreation andconservation. The purpose of the report is not to make detailed recommendations: rather it is a quantifieddescription of many aspects of one of Scotland’s most widespread and varied natural resources.
The beaches of Scotland
Commissioned Report No. 109Contractor: W. Ritchie and A.S. MatherReprint: 2005 (originally published 1984)
C O M M I S S I O N E D R E P O R T
Summary
For further information on this project contact:Alistair Rennie, Scottish Natural Heritage, Inverness. Tel: 01463 706450
For further information on the SNH Research & Technical Support Programme contact:The Advisory Services Co-ordination Group, Scottish Natural Heritage, 2 Anderson Place, Edinburgh EH6 5NP.
The fieldwork that preceded this report was made possible by the financial support of the CountrysideCommission for Scotland who also provided valuable guidelines for the direction and content of both theregional survey work and the compilation of this report. Nevertheless, the authors alone are responsible forthe factual content and views contained in this publication.
The authors would like to record their gratitude to Professor R.E.H. Mellor and the late Professor K. Walton,and for the general support of the Department of Geography, University of Aberdeen. Dr. J.S. Smith,Mr. R.S. Crofts, Mr. N. Rose and Mr. R. Wright were co-authors of several of the regional reports, and theirassistance is gratefully acknowledged.
The facilities of the Computing Centre of the University of Aberdeen are also acknowledged, as is theassistance of many members of the technical and secretarial staff of the Department of Geography.
Special thanks are due to Mrs. J. Calder and Miss A. Croucher for typing difficult manuscripts.
2 THE PHYSICAL NATURE OF THE BEACH RESOURCE 92.1 The development of beaches, dunes and related surfaces 92.2 The dimensions of beach and dune systems 152.3 Machair and links relief patterns 232.4 Bare sand areas – erosional and depositional 272.5 Beach materials 352.6 Vegetation and habitats 41
3 CHARACTERISTICS AND USE OF THE BEACH RESOURCE 503.1 Accessibility 503.2 Ownership and tenure 523.3 Scenic quality 553.4 Nature conservation 573.5 Land use 593.6 Recreation 63
REFERENCES 69
Appendix 1 – Calculation of wind roses 70Appendix 2 – Beach names – Key for figure 1.1 73
List of f iguresFigure 1.1 Distribution of beaches 2–5Figure 1.2 Boundaries of local authorities 6Figure 2.1 Model of beach/dune system 9Figure 2.2 Beach system flow diagram 10Figure 2.3 Wind roses for selected meteorological stations 12Figure 2.4 Mean Spring tidal ranges in metres 14Figure 2.5 Sketch block diagram near pipeline landfalls 26Figure 2.6 Histogram of median sand diameters 37Figure 2.7 Histogram of sand calcium carbonate content 37Figure 2.8 Typical vegetation profile 47
List of platesPlate 1 Aberdeen 48Plate 2 Traigh Cille Ionnaig, Coll 48Plate 3 Balmedie, near Aberdeen 49Plate 4 View from Ben Hough, Tiree 49
Sandy beaches are distributed unevenly around the shores of Scotland. They are completely absent fromlong stretches of coastline, while elsewhere most of the coastline is composed of beaches and dunes. Thedistribution of beach units, as defined in this study, is illustrated in Figure 1.11. Perhaps the main feature ofFigure 1.1 is the large number of beaches on the islands off the west and north coasts. Over half of thebeach units are on islands, which account for under 40% of the coastline. Another striking feature is thecontrast in distribution between the east and west coasts of the mainland; the majority of beach units are onthe east and southwest coasts and there are relatively few units on the north and northwest coasts. The innerfirths and estuaries are poorly endowed, while the outer firths and parts of the northeast shoulder of Scotlandare characterised by large numbers of beaches.
Table 1.1 indicates the overall size (in terms of length) of the beach resource and shows clear disparitiesbetween the major administrative areas whose boundaries are shown on Figure 1.2. In total, beach lengthextends to around 760km. This figure compares with a total length of coastline of just under 12,000km ifmeasured to the tidal limit, or around 9,500km if measured to the points where estuaries narrow to 1km.Beaches therefore comprise just under 8% of the coastal length, excluding the inner estuaries.
1 Appendix 2 lists the names of beaches shown in Figure 1.1
Table 1.1 Distribution of the beach resource
Region or islands area Beach length as Coastal length percentage of coastal
Beach length1 km length of each(a)2 (b)3 region or island area
km (a) (b)
%
Borders 2.8 33 33 8.5 8.5
Central 0.0 30 98 0.0 0.0
Dumfries and Galloway 35.4 390 447 9.1 7.9
Fife 43.2 165 201 26.2 21.5
Grampian 107.4 309 369 34.8 29.1
Highland 111.8 2378 3290 4.7 3.4
Lothian 37.3 121 121 30.8 30.8
Strathclyde 181.4 2453 2578 7.4 7.0
Tayside 23.6 102 130 23.1 18.2
Orkney 59.8 836 890 7.2 6.7
Shetland 14.6 1150 1513 1.3 1.0
Western Isles 145.2 1428 2039 10.2 7.1
762.5 9395 11709 8.1 6.5
1 Sum of beach units as defined in this study.2 Excluding estuaries less than 1km wide.3 To tidal limit.
In terms of relative length of sand beach, three distinct groups of regions and islands areas may berecognised. The first of these is the east coast group of Grampian, Tayside, Fife and Lothian, where thebeach length is over 20% of coastal length. This percentage is nearly three times the Scottish average.
On the other hand, Central and Highland Regions and Shetland have less than 4% of their coastlines in theform of sand beaches (less than half of the national average). The remaining group – Strathclyde, Dumfriesand Galloway, Borders, Orkney and Western Isles – approximate to the national average, with percentagesof between 6 and 9.
Within each region, an uneven pattern of distribution occurs. In the Western Isles from Harrissouthwards, the beaches and machairs of the west coast contrast strongly with the rocky east coast. In Fifeand Lothian, most of the beaches are concentrated in the districts of North east Fife and East Lothian. InStrathclyde, Kyle and Carrick District contains 18% of the region’s beach length, but only 3% of the region’scoastline. Another example of the irregularity of distribution is the contrast between the inner parts of firthssuch as the Firth of Clyde, Forth, Solway and Tay and their outer stretches. Beaches are almost completelyabsent in the inner sections, but are numerous in the outer. Uneven distribution also extends to the localscale. On islands such as Mull or Islay, for example, clusters of beaches on some parts of the coastlinecontrast with rocky shores on other parts. In Grampian Region, sand beaches extend continuously for over20km between Peterhead and Fraserburgh and also between Aberdeen and a point north of Ythan Estuary,while the coastline between these segments and to the west and south is composed almost exclusively ofbold cliffs.
Distribution depends on a number of factors, of which one of the most important is the availability of a suitablesupply of sediment. Glacial deposits on the seabed have probably been a major source of supply in manyareas, but it is also noticeable that beaches are scarce (and usually poorly developed) where certain rock typesoccur. For example, there are few sand beaches on the basalt areas of Skye and Mull. Another factor whichinfluences beach distribution is exposure. On some parts of the coastline, such as the inner firths and sea lochs,wave energy may be inadequate to transport sand for beach development, while on the most exposed coasts,such as part of the west mainland of Orkney, the energy level is so high that most of the beaches are composedof boulders and cobbles. Local topography is also important. On some parts of the coastline, such as eastCaithness and Kincardineshire, the coastal slope is so steep that there are almost no sites where sand mayaccumulate, even if other conditions were favourable for beach development.
The distribution of beach types is almost as varied as the distribution of beach units. This topic is discussedmore fully in Section 2.2, but as a broad generalisation two main types may be recognised. In much of thelowland area, the typical beach is long and straight, with a prominent dune ridge and an area of links whichmay rest on a raised beach whose inner margin is defined by an abandoned sea cliff. This type of extensivebeach unit is also found in the Eastern Highlands (especially in Sutherland) and, without the raised beachand abandoned cliffline, in Orkney, the Western Isles, and Coll and Tiree. Whereas the typical lowlandbeach occupies an open coast, the upland type is more usually found in a bayhead. Typical examples occurin northwest Sutherland and Wester Ross, in parts of Argyll and to some extent in Galloway and the easternpart of Lothian and Borders Regions. These upland beaches are typically enclosed between bold rockyheadlands, and in many instances their associated areas of blown sand are small and more stronglyinfluenced by the sub-sand topography than their lowland counterparts, which frequently contain extensiveareas of links or machair.
Uneven distribution therefore characterises almost all aspects of the beach resource; beach locations, beachlengths, beach types, and forms and extents of blown-sand deposits are distributed very irregularly aroundthe country. Some parts of the coastline are composed almost solely of sand, while other parts are almostdevoid of beaches.
2.1 The development of beaches, dunes and related surfaces
Beaches, dunes, links and machair1 may be regarded as a unified system whereby sand is transferred bywave action from nearshore sediment banks to the beach. Under certain conditions the wind carries sandlandwards and, if conditions are suitable, dunes may form and, in time, become stabilised by vegetation(Figure 2.1). Sand may also spread further inland to form links or machair surfaces. For any form of coastalmanagement it is necessary to appreciate the main factors that influence the development of dunes, machairsand links from the sand supply that is provided by suitable beach accumulations.
Figure 2.1 Model of beach/dune system
Many factors may alter the rate at which the system operates. Sand supply, wave energy and tidal levelsare crucial to the physiographic development of the beach; wind energy and other climatic factors(especially in their control of the development of vegetation) largely determine how and where dunes andrelated landforms are formed. Like most natural systems, the linkages between different elements may bedirect or indirect (Figure 2.2).
These natural coastal processes can be easily disrupted, particularly by external factors such as land-usechanges or removal of sand from the system. Since the beach is normally part of a wider coastal environment,changes occurring beyond the boundaries of the beach system can produce considerable modifications tobeach and dune systems, especially if the supply of sand to the nearshore sediment bank or beach is altered.
In the ideal model, sometime after their initial formation, dunes should reach and remain in a state ofbalance, in that sand added to the beach zone just replaces the quantities that are lost by the wind carryingsand beyond the links and onto the surrounding landforms. This balance cannot be achieved quickly as ittakes considerable time, perhaps centuries, for sand to pass through all the stages of nearshore sand banks,beaches, dunes, links and, finally, marginal surfaces. During this long period, short term fluctuations inevitably
1 Machair is a term used in the Highlands and Islands of Scotland to describe the short grass pasture to the landwards of thecoastal dune ridges. In other parts of Scotland the term links is more common. In general, machair and links can be regardedas more or less synonymous. (For a fuller discussion, see Ritchie, 1976.)
occur, especially in the crucial zone at the junction of the upper beach or nourishment zone and the face ofthe frontal dune or coastal edge. This sensitive zone is normally the best indicator of contemporary duneforming processes. If there is abundant sand on the upper beach, the frontal dune is usually vegetated; thedunes show signs of recent growth in height and are possibly advancing seawards. Dune vegetation isvigorous and may contain pioneer species. Erosion forms are rare and slope angles tend to be low. In contrast,if sand supply is deficient or there is a change in the nature of wind or wave attack, the coastal edge becomesa steep dune-cliff. The coastal edge is usually bare of vegetation and erosion forms are evident. There isnormally a sharp break of slope between the unvegetated upper beach and the frontal dune slope.
Figure 2.2 Beach system flow diagram
With small short term natural fluctuations in, for example, wave energy or tidal water levels, the upper beach-coastal edge may alternate between retreat and advance. To illustrate this point, the effect of storm wavesattacking the face of the dune may be considered. Wave backwash pulls sand from the dune onto thebeach. This sand is added to the beach and reduces its gradient, thereby increasing its resistance to waveattack and reducing the frequency of direct wave erosion of the dune face. In contrast, if these changes arenot short-term and fluctuating, but relate to longer, more persistent or permanent changes in sand supply, inwave energy or in water levels, then the dunes respond by either retreating by a series of erosional events,or, in contrast, if sand supply continues to be available (or wave conditions are more constructive or sealevels are lower) by advancing seawards; a process described as progradation. Normally, such pro-gradation is characterised by a series of parallel dune ridges advancing seawards.
Vegetation is the best single index of stability and contemporary processes. The density, vigour and relativedominance of the tall dune grasses – Marram, Sea Lyme and Sea Couch Grass – are excellent indicators ofsand deposition and redeposition and, to some extent, soil and drainage conditions. In the extreme case, theabsence of vegetation inevitably means that the surface is unstable and liable to rapid morphological change.Although pioneer species on the upper beach – eg Sea Rocket – usually indicate backshore accretion and anabsence of short term erosional processes, such occurrences should be confirmed over the wider beach zoneas it is not uncommon to find areas of local accretion in a beach that is suffering net retreat. Further inland,the general appearance and species composition of the links and machair areas reveal something of seasonalchanges, especially winter flooding and, to the experienced eye, some idea of stability and soil conditions.
In addition to vegetation the study of slope angles, combined with a careful evaluation of the various typesof break of slope can provide valuable information about the relative activity of beach and dune processes.
Mature, stable dune and links surfaces tend to be level or low angle features. Steep slopes are signs ofyouthful development and, if coupled with areas of bare sand, indicate recent or continuing movement ofsand by the wind. The most important slope is the front of the foredune where undercutting by the sea, andwind erosion on the one hand are easily contrasted with stability, progradation and growth on the other.
There are other diagnostic landforms further inland such as ridges with distinctive escarpment features whichnormally indicate the edge of some kind of deflation surface. Low vegetated sand hillocks or hummocks mayusually be interpreted as recent depositional forms. Flat areas at or near the water table are almost invariablyold deflation plains where wind erosion has been halted naturally by the dampness of the sand. Some of thebest examples of such surfaces are found in the Outer Hebridean machair plains. Corridor and V-shapeddepressions in dune ridges indicate concentrated wind erosion to which the general term blowouts is applied.Blowout forms vary in height, depth and penetration, but reach their optimum development in the main coastaldune ridge. Large scale erosion forms are widespread but spectacular examples are found at Machrihanish(Kintyre), Eoligarry (Barra), Dunnet Bay (Caithness) and Rattray Head (Buchan). Blowouts may be active orcompletely stabilised. In the lee or landward side of most blowouts are hillocks, ridges and secondary duneforms formed by deposition of the eroded sand. Again, these may be active or fossil features. Blowouts oftengive a good indication of the direction and possible severity of wind erosion. The amount of blowout activityalong with other geomorphological evidence is a good indicator of the general stability of the area. Closerstudy of such erosion forms can also reveal the possible causes, natural or induced, of such instability.
Many of these natural features are modified by the direct and indirect activities of man. Drainage, sandremoval and overgrazing tend to be the main disruptive factors but, in places of heavy recreational use, thereis often direct impact by trampling and the movement of vehicles. In contrast areas of afforestation have beenmajor stabilising influence on some dune systems eg Culbin (Moray), part of Morrich More (Easter Ross). Otherareas of stability are the semi-natural dune and links areas that are carefully managed golf courses or coastalparks and amenity areas for nearby urban areas. A special form of modification is the construction of beachdefences such as sea walls, piers, groynes and other forms of beach stabilisation measures. Coastal defences,dating from the early 1940s, especially anti-tank blocks (ie concrete cubes one or two metres high and up toone metre in width) are still present on parts of the lowland coastlines of the east of Scotland – eg BurgheadBay (Moray), Tentsmuir (Fife), Largo Bay (Fife). The effects of these and other beach/dune constructions arediscussed in Chapter 2.7, but it is worthwhile to note here that as well as their visual impact they can alsoaffect such processes as wave and wind action and thereby modify part of the beach-dune-links system.
Beach and dune evolution is ultimately controlled by weather conditions. Wind strength and direction not onlycontrol the general drift of sand from beach to dune, but also from dune to links and machair surface. Windsalso shape the size and orientation of dune and other forms of sand deposition. Figure 2.3 shows wind rosesfor a selection of coastal meteorological stations, and indicates the dominant and subsidiary directions of windattack. This information must be used with caution since local effects might create wind vectors that are quitedifferent from those provided by the nearest meteorological station. In many beach areas, particularly in theHighlands of Scotland, mountains and plateaux may run close to the coast and offer considerable shelter fromspecific directions. On a smaller scale, dune systems have their own local climates whereby frontal dunesmodify the wind flow that impinges on more landward features, and blowouts and other erosional hollowsoften have wind speeds considerably above that produced by regional and local winds.
Wind is also responsible for determining the angle and amount of wave energy crossing the nearshore zone
and beach, and occasionally attacking the coastal edge directly. Again, there are complex regional and local
factors to consider. A few coastlines, such as the west side of the Outer Hebrides, Shetland, the Orkneys and
a few sectors of mainland coastline, receive both long period, high energy swell which has developed across
1. Tidal range distribution of energy and variability of beach exposure.
2. Possibility of exceptional rise in level of sea surface eg surge tides, to produce the possibility of directwave attack on the dunes.
3. Pattern and amount of wave energy.
4. Possibility of salt spray affecting vegetation and stability.
(b) Climatic
1. General weather conditions as a control of physical and biological activity, especially the type andvigour of vegetation.
2. Wind directions, strengths and seasonal changes at both regional and local level.
3. Precipitation as a control on the movement of sand.
(c) Other local processes
1. Direct slumping and slope failure of dune and sand hill slopes.
2. Local stream action as a direct factor of erosion and/or deposition.
In the final analysis, and omitting the range of modifications that are introduced by the presence of Man,most of the factors and conditions that are listed above interact with each other; a process moulds a form,but the form subsequently modifies the process. This concept applies to all types of landform evolution, butthe unconsolidated and fragile nature of coastal dunes systems at the interface of three environments the sea,the atmosphere and, to a lesser extent, the land gives this concept added significance and makes the beachand dune environment particularly vulnerable to relatively rapid and extensive change.
2.2 The dimensions of beach and dune systems
Areas and other dimensions
This section of the report attempts to set out quantitative information relating to areal and linear dimensionsof the beach and dune systems in Scotland. Inevitably a number of problems arose in the collection of thisdata. For example many of the more extensive physiographic units such as Aberdeen to Collieston(Grampian), the west coast of South Uist, Irvine Bay (Firth of Clyde), Tentsmuir (East Fife) and many otherswere studied in the field as a series of subdivisions many of which correspond to topographic, land use ordistinctive functional elements. For example the beach and dunes between Aberdeen and Collieston is asingle physiographic system, subdivided by the outlets of the River Don and the River Ythan. This area alsocontains, in the south, the beach of Aberdeen City and, in the north the National Nature Reserve of Forvie.As a consequence of this need to subdivide some of the statistical information contained in subsequenttabulations should not be regarded as having great precision but rather as a general indices from which
valid generalisations can be made. This introductory qualification is applicable to the statistics for averagebeach length where the longest beaches are found in the Outer Hebrides, especially the Uists, and on theMoray and North Sea coastlines north of Aberdeen. The shortest beach lengths are in Shetland and theOrkneys with the west mainland of the Highlands also having many relatively small beach units.
The general average emerges as being around 1km in length with the lowland beaches of both the Firth ofClyde and the North Sea littoral being substantially longer, In general, the use of a mean value is deceptivein that in most regions there are a few very large units and a great number of small units. A closerexamination of the actual values of beach lengths reveals that the great majority of the beach lengths (likethe areas of beaches, dunes, machair and links) are small, a fact that is illustrated on the distribution map(Figure 1) where the great number and wide scatter of beaches that are less than 1km long are clearlyidentified
Another problem in collating data, again a difference between Lowland and Highland and Island beaches,is the difficulty of delimiting the transitional areas where the blown sand of links and machair gives way toother landform surfaces. Several reasons account for this difficulty. Most of the lowland links rest upon someform of raised beach terrace or surface and, although this was not uncommon in parts of the Highlands andIslands, this difference between the two regions is nonetheless quite striking. Further, the raised beaches tendto be composed of sand, and it is on the evidence of surface appearance almost impossible to distinguishthe landward limit of wind blown sand. Another reason for the lack of confidence in defining the landwardlimit of blown sand areas in lowland Scotland is the encroachment of houses, recreational areas and otherman-made features onto the landward part of the links.
An equally common problem in defining the blown sand boundary is the spread of improved and relativelyintensively modified agricultural fields beside and on blown sand areas. In many Highland areas the limitof cultivation is a particular fence or dyke that is normally a sensitive indicator of the nature of the soil andunderlying landform, but this is not possible in the extensive lowland plains along the Moray coast,Aberdeenshire, Fife and Ayrshire where high quality farmland often extends onto old links type surfaces. Anadditional problem in particular areas in the lowland series of beaches is afforestation. About 5.6% of thebeach units are classified as having some form of afforestation, and these tend to be big units, such asCulbin or Tentsmuir. The significance of forestry as a land use in dune areas is described later (Section 3.5),but it poses problems for the definition and description of the underlying landform patterns.
Notwithstanding these difficulties of definition and measurement an attempt is made to provide mean valuesof the average size of all the dune and beach areas in Scotland. Although there is a measure of doubtrelating to specific absolute values there is greater confidence in the percentage ratios that reveal substantialdifferences between regions and in relation to national average values. This information is presented in Table2.1. For the three basic landform units the total percentage ratios for all Scottish beaches are BEACH;DUNE; LINKS or MACHAIR, 36.4; 7.0; 56.6 or rounded to 5:1:8. The value of 7% for dunes is aremarkably small figure and reveals how the most dynamic and fragile zone of the total system is normallyonly a small part of the whole. Thus as a proportion of the land surface, coastal dunes are relatively rarelandforms. At the regional level only in those parts of Strathclyde in the Highlands and Islands, in HighlandRegion and in the Western Isles do they constitute approximately 10% of the total beach complex area. Inabsolute size the smallest dune areas are in Shetlands, Orkneys, Strathclyde (Lowlands), Dumfries andGalloway, and Lothians and Borders. Combining absolute and relative provision, although having fine
beaches Dumfries and Galloway Region is poorly endowed with coastal dune forms, a fact which givesimportance to the only large, complete system at Luce Bay. The need to look at both absolute andpercentage figures is well illustrated by Tayside and Fife where the presence of single, relatively narrowcoastal dunes at the coastal edge of very large blown sand areas eg Barry Links, Tentsmuir, Largo Bay, isworthy of note.
Table 2.1 Areas
Mean values in hectares
No.of Beach Dunes Machair or Links TotalUnits % % %
Strathclyde in H. & I. 136 23.7 37.9 7.0 11.2 31.8 50.9 62.5
Total area of Sand (Beach + Dunes + Links/Machair) in each Region
Total Area (Hectares) % Scottish Total
Strathclyde (Highlands and Islands) 8,500 17.0
Strathclyde (Lowland) 2,224 4.4
Highland 6,402 12.8
Western Isles 10,466 21.0
Orkney 2,428 4.8
Shetland 299 0.6
Grampian 8,269 16.5
Tayside and Fife 6,616 13.2
Lothian and Borders 2,501 5.0
Dumfries and Galloway 2,368 4.7
TOTAL 50,073 100.0
NOTE: These figures do not include transitional areas of blown sand which can be extensive, especially in Highlands and Islands.
In summary, taking the total areas of sand embodied in beach, dune and machair/links, but excludingtransitional surfaces, the Western Isles Region contains about one fifth of all the sand of the Scottish coastline.Shetland has very few areas of sandy coastline. The east coast from Inverness to the north side of the Firthof Forth contains about 30% of all the beach and blown sand areas, a fact that could be related to theextensive lowland nature of the general coastal hinterland, sedimentary bedrock and an abundant sandsupply from glacial and perhaps more important fluvio-glacial sources.
The Western Isles, Dumfries and Galloway, Tayside and Fife and Grampian Regions have values that aresignificantly different from the national pattern, whereas Strathclyde and Highland Region approximate closeto the national values. A further subdivision by District for selected areas is given in Table 2.2 to highlightdifferences at another regional scale.
These figures reinforce the great variety of dune formations in Scotland and the difficulty involved in makingbroad general statements, particularly with regard to regional patterns. Further, these initial tentative studiesprovoke some basic questions, such as what should be understood by the term dune system and what areits essential components?
The setting of the beach complexes
The Beach complexes of Scotland have a wide variety of physiographic settings. Tabulation 2.3 shows thefigure for the Highlands and Islands along with the equivalent percentages for all the beach complexes. Whenthe same circulation is repeated for all beaches by Region, a different series of values is obtained (Table 2.4).
Table 2.4 requires some further explanation on the method of construction. The “bayhead” category (thelargest and most widely distributed group throughout Scotland) describes a curved beach set betweenheadlands. Such beaches are usually deeply set and as a result of their shape are not subject to substantiallateral or alongshore changes in beach morphology. If the headlands are spread more widely, or if thecurvature lessens, or if it is less set-back, then the beach is placed in the “open coast” category. The othercategories are self explanatory except for “intersecting minor bays”. This type is common along many partsof the West Coast and Inner Hebrides and describes small beaches that link together at low water, but areotherwise separated by rock outcrops, minor headlands and ridges. The “other” category is largely used forsmall islands, such as the Monach Islands off North Uist, where the entire area was studied as a unit. Thedistinction between “spit” and “isthmus” is one of scale and origin, the former being smaller eg mouth ofRiver Don in Aberdeen is a spit, but Balnakeil in Northwest Sutherland is an isthmus.
Table 2.3 Setting: Percentage of all beach complexes
Highlands and Islands All Scotland
Bayhead 48 45
Intersecting Minor Bays 13 12
Open Coast 12 16
Marginal Strip 9 10
Island Grouping/Other 5 5
Isthmus or Peninsula 4 3
Foreland 4 5
Loch Head 3 2
Spit 2 2
The distribution of types shows an above average number of bayhead units in parts of Strathclyde (includingthe larger Inner Hebridean islands), Orkney and Shetland, and Dumfries and Galloway. Lowest values are alongthe east coast of the mainland where open coast situations are most common. This reflects the lack of indentationand the lowland nature of the coastal hinterland. It also correlates with the prevalence of raised beaches (seeend column of Table 2.4). Above average totals of intersecting minor bays are found in the Highland Region,in some of the Inner Hebrides and in Argyll and Bute District. Beaches formed on peninsulas are most commonin the Outer Hebrides and Shetland, and those on spits are most common in Wigtown District.
Several quantified variables about beaches were obtained during field surveys. These include beach width,length and area, with the last item being subdivided into inter and supra tidal areas. This is an importantdistinction as it is the upper beach, above high water mark, that provides the main source for sand movementonto adjacent dunes. It is also the area that protects the coastal edge from direct wave attack. The beachgradient and type of sediment were also recorded during fieldwork.
The ratios of backshore to intertidal beach by Region are given in Table 2.5, along with average beachgradient in degrees and average distance from high water mark to the 5-fathom isobath. All the variablesin Table 2.5 show wide but relatively predictable differences. There is clearly a relationship with tidal range(see Figure 2.4 and Table 2.5) in that wider beaches should be exposed with greater tidal range as longas beach gradients are similar, and Table 2.5 shows little variation in average beach gradient, being leastin Strathclyde Region and highest in Grampian Region. The second part of Table 2.5 shows the frequencyof different gradients by Regions and further reinforces the pattern as described above. Shetland has narrowbeaches and, as indicated by the distance to the 5-fathom isobath, the steepest offshore gradient.Strathclyde and Orkney also have relatively steep offshore gradients. The long distance to the 5-fathomdepth contour for the Western Isles might appear surprising in that all these beaches are open to the AtlanticOcean, but the sea bed that extends westwards from the Outer Hebrides is essentially an ancient rockplatform surface of low gradient and shallow depth.
Referring to Table 2.5, the Regions with the widest average areas above high water mark are LowlandStrathclyde, Highland, Western Isles and Lothian and the Borders Regions. In these areas there appear tobe many beach areas with wide nourishment zones of dry sand on the upper beach available for transportonto the coastal dune ridge. Conversely those upper beach zones appear to be severely restricted inDumfries and Galloway and Orkneys Regions. In addition to their importance for dune development, narrowbackshore areas do not provide the same protection to the toe of the dune ridge against exceptionally highsea elevations.
If there are shingle ridges at the upper limit of beaches, then the important exchange process wherebysand may be transferred to the beach from the base of the dune to the beach cannot take place and, asdiscussed in Section 2.4, about 6% of all beaches have substantial shingle ridges above high water markand about 4% have some form of artificial construction on the upper beach. Regions having aboveaverage percentages of either shingle or artificial constructions are parts of Strathclyde, especially aroundAyr Bay, and in the Inner Hebrides, Tayside and Fife, and in Lothian District. Orkney has a high number ofshingle ridges. This supplementary information modifies the generalisations that are made about thesignificance of backshore widths to the natural processes associated with the transfer of beach sand tocoastal dune ridges.
A special type of coastal edge which is of considerable ecological importance is saltmarsh, and where theseareas occur in association with beach, dunes, machair or links they have been noted. Usually this form ofsaltmarsh has a high sand content in the soil profile and has therefore been described as sandy saltmarsh.Table 2.6 shows the distribution of sandy saltmarsh by Region and clearly reveals the relatively frequentoccurrence of this ecologically important zone. The high value for Grampian is partly explained by severalsmall saltmarsh areas that are associated with the lower courses of minor streams and drainage channels
Figure 2.5 Sketch block diagram near pipeline landfalls
Flooded and marshy areas
Many machair and links areas contain marshy or flooded areas. Frequently such flooding is seasonal and lowlying slacks or hollows may be up to a metre deep in fresh water for the winter part of the year. Such seasonalflooding was not studied in detail during the surveys, but information is available for the dune areas north ofPeterhead (Ritchie,1981) where complete flooding to create a “winter loch” is recorded from about midOctober to early May (Figure 2.5). This flooding is important to the type of vegetation and wildlife in the area,including roosting and feeding of migratory birds and, in a few places, for access and use. Since fieldworkfor the beach survey programme was normally done in summer, it was necessary to interpret such floodingindirectly from morphological and vegetation patterns, since most of the areas that flood in winter become quitedry in summer. Nevertheless, as shown on Table 2.9, an attempt was made to estimate the degree of floodingand marshiness along with a record of the presence of stream drainage within the blown sand area.
As expected, the overwhelming majority of dune and machair areas are dry and the greater proportion ofsuch areas have some form of stream. About one in six of all dune and machair areas are classified ashaving greater than 10% of their areas as marshy (with or without streams). The areas with greaterproportions of marshiness are in Orkney, in Shetland, and in Dumfries and Galloway. In the Northern andWestern Isles, many of these marshy areas include areas of ground that are adjacent to fresh water lochsthat have been impounded by blown sand or by such constructive forms as bars and spits. There is evidenceto suggest that many marshy areas in dunes, links and machair areas would be more extensive were it notfor substantial drainage works arising from agricultural improvements. In a few areas artificial drainage hasalso been introduced to improve surface conditions for building use. A special case of such artificialdrainage occurs on golf courses.
2.4 Bare sand areas – erosional and deposit ional
Most sand dune systems contain areas of bare sand. These surfaces may be extensive as at Forvie andFoveran (Grampian) where they are major landform elements. Bare sand surfaces within the dune andmachair/links area are potentially unstable and are normally zones of sediment transport. Around theScottish coast these surfaces are mainly produced by erosion and as such can be regarded as unstablelandforms, particularly where instability has been produced or aggravated by some external factor such asvehicle tracking, excessive rabbit populations, sand quarrying, overgrazing or some form of uncontrolledrecreational use. Nevertheless, deposition can produce equally unstable surfaces. Sand accretion is theprocess by which dunes are created and, in time, these sand accumulations are fixed by vegetation. Theredeposition of sand that has been excavated from erosion features, such as blowouts, creates similarfeatures of accretion. Thus bare sand areas are produced by apparently opposing processes, erosion anddeposition, but the surface has the common attribute that it is potentially mobile; sand can encroach ontoadjacent vegetated surfaces and, as such, are unstable.
Arguably, by the main process of their evolution, sand dune systems require a number of bare sand areas,especially near the coastal edge, so that the essential process of transferring sand from the upper beach andforedunes inland can be accomplished. Further, in a young accreting system the proportion of bare sandwill be high whereas in an old mature system there should be little or no mobile bare sand areas. For anyindividual beach/dune system it is comparatively easy in the field to distinguish between erosional anddepositional sand surfaces. It is also possible to distinguish between natural erosion and erosion that hasbeen triggered or aggravated by some external factor. To aggregate these different types of bare sandsurfaces for all the dune systems of Scotland it is necessary to avoid terms like eroding area or redepositionalarea and simply produce a measure of the average size and relative percentage of the blown sand area
that is bare of vegetation. This produces a figure of 2.5% (ie total bare sand area as a percentage of thetotal area of dunes plus links/machair). However, 321 of the 647 beach units in Scotland have little or nobare sand areas, and if these areas are removed from the calculation then the mean percentage area ofbare sand in the remainder is approximately 3%. Some of the larger dune and machair areas in Scotlandthat have particularly large percentages of bare sand are Balephetrish1 in Tiree (24%), Sanaigmore in Islay(23%), Invernaver (21%) and Clachtoll (27%) (Sutherland) and Achnahaird Bay (22%) in Wester Ross, Brekinin Shetland (29%) and Allasdale (24%) in Barra. Opinan (Wester Ross) has an exceptionally high area ofbare sand but most of this is in the extensive transitional area inland from the machair. Sandwick in Uist isalso a small beach unit with a very large percentage of bare sand surfaces.
Table 2.10 Localit ies with large bare sand areas
Name Bare sand area (ha.) Bare sand area %
Eoropie (Lewis) 11 13
Barvas (Lewis) 13 9
Traigh Bagh (Tiree) 14 10
Sorobaidh (Tiree) 12 9
Machrihanish (Kintyre) 16 5
Dunnet Bay (Caithness) 11 1
West Coast Berneray 14 3
Balranald (N. Uist) 11 3
Kirk (N. Uist) 13 9
Baleshare (N. Uist) 13 3
Eochar/Dremisdale (Uist) 15 2
Eoligarry (Barra) 19 16
Allasdale (Barra) 11 24
Varlish (Barra) 13 60
Culbin (Moray) 15 1
Strathbeg (Grampian) 21 10
Rattray Head (Grampian) 12 16
Rattray Bay (Grampian) 23 13
Sands of Forvie (Grampian 35 8
Foveran and Drums (Grampian) 26 15
Menie and Petens (Grampian) 20 7
Balmedie (Grampian) 25 11
Montrose (Tayside) 15 8
Barry Sands (North) (Tayside) 26 5
1 Balephetrish is the best example to illustrate an aspect of the measurement (by electronic planimeter) of the bare sand areawhich is explained in detail on p. 25 of the Beaches of the Highlands and Islands of Scotland (Mather and Ritchie, 1977).A difficulty occurs where a section of the coastal edge has been eroded by the wind to an extent that it is a substantialdistance landwards of the highest tide level, thereby creating a bare sand surface on the seawards side of this section ofthe dune front. These surfaces are a continuation of the beach zone but are not normally within the sweep zone of waveseven during storm conditions. Accordingly, they are included in the measurement of the landward bare-sand acreage.A similar type of bare sand area on the seawards side of the coastal edge is found at Eoligarry in Barra where two orthree large blowouts have coalesced and produced a large bare sand area, contiguous with the upper beach zone.
Beaches with high perceived erosion damage Beaches with bare sand ratios greater than 20%
Dalmore CrossMangersta DalmoreGarry BostaCul Na Croise MangerstaMorar Mealasta IslandPort An T Saoir GarryTraigh Tuath Achaidh MhorCladdich MorarSanaigmore Samhnan InsirTralee Bay Port An T SaoirSango Bay BasapollKervaig Bay Corpach CoastOldshoremore SanaigmoreClachtoll CarskeyAchmelvich MachariochAchnahaird Bay SannoxGruinard South MachrieMellon Udrigle SannickOpinan InvernaverSand of Meal ColdbackleKirk Sand MelnessSandwick Unst Traigh Allt ChailgeagLundawick SheigraRosinish OldshoremoreEoligarry ClashnessieBagh A Dheas ClachtollFindhorn AchmelvichRattray Head Traigh na TeampuillUgie/Lunderton Achnahaird BayFoveran/Drums MungasdaleBalmedie Gruinard NorthColdingham Bay Gruinard SouthGullane Mellon UdrigleGosford Bay MellanguanMontrose OpinanBarry Sands (East) Sand of MealMonifieth Brekin
Balta IslandSandwick UnstLundawickSandside BayScrimpoRosinishAllasdaleSandrayVarlishBanff Bay
In addition to the geomorphological implications, this table (ie Table 2.15) of differences in beach sedimentsand other characteristics has ecological implications in that a beach with extensive rock platforms ispotentially a richer and more varied intertidal habitat than a pure sand beach. Similarly, a beach withcontrasting rock outcrops is often more scenic than a uniform sweep of sand.
Composition of sand
Sand samples were collected from almost every beach in Scotland during the course of fieldwork. Thesample was not less than 500gm and was removed from the approximate high tide level in the centre ofthe beach area. Additional samples were taken from dunes, links and machair, as appropriate. The sampleswere sieved by standard methods and a single statistic, the median diameter, was used to characterise eachsample.
Examining all the beach sands by size produces a histogram (Figure 2.6) that shows the relative absenceof sand in the coarser grades. The mean size of all beach sands is 370 microns.
In general, about three quarters of the beach sands of Scotland are in the fine–medium category(ie 150–350 microns). The histogram (Figure 2.6) shows a secondary peak in distribution towards the upperend of the medium grade (ie over 650 microns). These coarser sands come from widely scattered beachesand there is no pattern in the distribution. In some cases the use of the statistic of the median causes problemswhere the sand sample contains an admixture of fine gravel into the sand matrix. The effect of this is to shiftthe median to a coarser level, and many of the samples in the 600–650 micron range are of this type. Thevery coarse sands relate to particular areas with local sources as, for example, the Coral Beaches (Skye),Ardnamurchan Point, Ardtoe (Moidart), Back of Keppoch, Elswick, Reawick, Carradale (Kintyre), Brodick(Arran), Marwick (Orkney) and the Whilk (near Ballantrae). These are widely scattered localities, but thereis a tendency for the northwest Highland Mainland and the Northern Isles to have more examples ofbeaches with a significant proportion of coarse-grained materials. The East Neuk of Fife also hascomparatively coarse sands. The beach sands of the Outer and Inner Hebrides and Lowland beaches arealmost invariably in the fine–medium size ranges (Table 2.16).
Sand sizes are a result of the combination of two factors – the original source and the history and mode oftransport to their site of collection. In Scotland the possible sources range from glacial and fluvio-glacialdeposits to local bedrock outcrops. The complexity of the patterns of glaciation and deglaciation need notbe emphasised here, but the net result is to produce a situation where it is almost impossible to suggest theultimate origin of beach materials. Indeed, those few areas where the beach sands can unambiguously berelated to a specific source, such as a local cliff or river outlet, are quite exceptional.
The history of sediment movement is also complex since it involves not only wave action and long shorecurrents, but also the possibility of wind transport. Where there is recent or past interchange between thebeach and the dune, then textural characteristics will be derived from both sedimentary environments.
Where there is unimpeded movement of material, coarser material should be found in higher energylocations assuming that a supply of coarse material was available in the original sediment source. Much ofthe Scottish coastline consists of beaches that occur in zones of impeded sediment movement, such as inbayheads, in estuary margins and in sea lochs (see Chapter 2.2), and the necessary conditions forsediments to acquire textural characteristics that reflect fully the mode of transport are therefore not available.Within individual beach units there are differences in sediments reflecting patterns of energy, but this wasnot a topic that was examined in any detail during the course of beach survey work.
Throughout Scotland, but especially in the Western and Northern Islands, the main source of sand forbeaches is comminuted shells of many types and species of marine organisms. Attempts to correlate thephenomenon of high shell sand content with other variables such as beach and offshore gradient, exposure,bedrock geology and other factors have produced little of any value or consequence. There is a generaltendency for the abundance of shell-derived sands to be associated with extensive rock platforms. This isespecially true of the Outer Hebrides, Tiree and a few isolated examples elsewhere as, for example, theEast Neuk of Fife. It must also be remembered that a high percentage of shell sand may reflect not only arichness of marine organisms within the catchment zone of the beach, but also a dearth of alternative sourcessuch as suitable rock outcrops (eg conglomerates, sandstones, grits), glacial and fluvio-glacial deposits orstream outlets.
Statistics relating to lime content (which is equated with shell content) are given in Table 2.17 which givesan indication of distribution by Region. Figure 2.7 shows the histogram for all beaches with a lime contentgreater than zero.
Table 2.18 Shell sand content within Strathclyde Region
Percentage calcium carbonate – number of casesDistrict
or 0 or 0–10 10–20 20–30 30–40 40–50 50–60 60–70 70–80 80–90 90–100Island missing
The distribution shown on Figure 2.7 for the 550 samples with a calcium carbonate content greater thanzero is a good indication of the importance of shell addition to the sediment supply of Scottish beaches.From an ecological point of view, even a few per cent of lime makes a significant difference to dune soilsand vegetation. As the percentage of lime increases, pH values rise quickly and in the Outer Hebrides valueshigher than 8.5 are not unusual. The histogram (Figure 2.7) also shows that there are more than fifty beaches
which are almost entirely composed of shell sand. These beaches occur in Mull, Coll, Tiree, Sanday andStronsay (Orkney), in several parts of the Outer Hebrides and in isolated beaches as, for example, Sannickin Caithness, Achmelvich in Sutherland, Balta Island, Saviskaill in Orkney, and Crail in Fife.
Table 2.17 clearly illustrates the dominance of shell sand in the Hebrides and Northern Isles, whereas theNorth Sea coast (except the East Neuk of Fife) is characterised by low values. Since Strathclyde containsislands, such as Tiree, with high values and Districts, such as Cunninghame, with low values, a further Table(2.18) gives a more detailed analysis. On the basis of Tables 2.17 and 2.18, Dumfries and Gallowayalong with the Districts of Kyle and Carrick and Cunninghame are seen to be areas with very low shell sandcontent in the beach sediments. Combining this information with the values for the islands and east coast ofKintyre, the greater Firth of Clyde littoral emerges as the main area of shell sand deficiency in Scotland.
2.6 Vegetation and habitats
Habitat diversity
The Nature Conservancy Council has compiled the following checklist as an appropriate, pragmatic wayof describing the habitats present in a coastal area:
Permanently flooded
1. Creeks and drainage channels
2. Lagoons
Intermittently flooded
3. Foreshore mud
4. Foreshore sand
5. Foreshore shingle
6. Foreshore rock
7. Saltmarsh and brackish marsh
8. Shingle beach lows
9. Sand dunes slacks
Terrestrial
10. Earth and cliff embankment
11. Sand dune and sandy beach
12. Shingle beach
13. Rock cliff and sea wall
14. Coniferous plantation
15. Deciduous woodland/scrub
16. Cultivated land
17. Dry heather moor
18. Wet moor (including mire, blanket bog)
19. Grass heath (not sand)
20. Machair
21. Freshwater marsh or swamp(Based on “Nature Conservation at the Coast”, Countryside Commission Special Study Report, Vol. 2, H.M.S.O.)
By scoring for these categories on a simple presence or absence basis some index of diversity at beachcomplexes can be gained in that the higher the number of categories present, the greater the probableecological richness of the area. The average value for all 647 units is 8.79 and for the Highlands andIslands 8.84. The average for areas with the statutory designation of Site of Special Scientific Interest is 9.41.
Table 2.19 shows the distribution of habitat diversity scores by region. In general, Orkney, Shetland andGrampian have below average habitat diversity scores. This suggests a relative monotony of terrainconditions within and near the beach areas. Fife and Tayside Regions have the lowest scores, with morethan half the beach units having a score of less than 7, and there is no beach unit with a score greater than11. These low scores indicate not only relative uniformity of terrain, but also reflect the comparatively largenumber of areas that are built-up or modified as, for example, by afforestation or golf course construction.
Regions with higher than average scores are Highland and Dumfries and Galloway. Lothian and BordersRegions also have slightly above average habitat diversity scores.
Individual beach units with scores greater than 15 are given in Table 2.20 and are therefore the areas inScotland with the greatest variety of habitats in or adjacent to the beach and blown sand areas.
Vegetation
The main vegetation types for the idealised beach unit are shown on Figure 2.8. Pioneer species are foundon the upper beach and their presence is the main criterion for assessing progradation of the coast. Asdescribed in Chapter 2.4, coastline accretion is uncommon around the Scottish coast and extensive areasof pioneer species, including the main dune grasses (which grow well on the upper beach if they are notinundated by sea water) are not common. Many beach areas, including eroding coastlines, have patchesof pioneer vegetation colonising localised zones of exceptional sand accumulation. Such areas are usuallytransient and are removed by the next period of elevated water levels during storm or surge tide conditions.
Table 2.20 Habitat diversity – highest scores
Area Region Score
Knockvoligan (Mull) Strathclyde 15
Loch Buie (Mull) Strathclyde 16
Killinallan (Islay) Strathclyde 16
Bridgend (Islay) Strathclyde 17
Tralee Bay (Argyll) Strathclyde 18
Coul Links (E. Sutherland) Highland 15
Applecross (W. Sutherland) Highland 16
Luce Sands (Wigtown) Dumfries and Galloway 15
Strathbeg (Banff and Buchan) Grampian 15
Sands of Forvie (Gordon) Grampian 16
Aberlady Bay (East Lothian) Lothian and Borders 15
Considering the main dune ridges a record was made in the survey of the main vegetation categories.A distinction made is between the two most characteristic dune building grasses, Marram (Ammophilaarenaria) and Sea Lyme (Elymus arenarius). As shown on Table 2.21, Sea Lyme tends to be more important
along the North Sea coast and in Orkney. It is rare in the Inner and Outer Hebrides and the northwestHighland mainland. It is also found along the Firth of Clyde coastlines, especially as discontinuous butvigorous patches along the backshore-foredune zone. There appears to be scope for further research intothe factors that control the distribution of these two species which are both of vital importance for the creationand development of coastal dunes. As an example of the peculiarities of the occurrence of Sea Lyme grass,consider the coastline between Aberdeen City and Strathbeg where geomorphological and pedologicalconditions are broadly similar, but Sea Lyme is totally absent from some areas for example St. Fergus, yet itis dominant in another – Ugie Beach, and it occurs as extensive patches elsewhere – for example Bridge ofDon. And why is it so overwhelmingly dominant in many Orcadian beaches? It has been suggested thatSea Lyme is favoured by sulphur-dioxide pollution, and if this is true then its expansion in several localities –eg Firth of Forth littoral, Aberdeen City beach, between Largs and Ayr – might be related to an aboveaverage content of this gas in the local atmosphere. Coastal edge grazing might be another factor. InOrkney its presence might be associated with the amount of seaweed on the upper beach. On the otherhand, similar masses of seaweed accumulate on Outer Hebridean beaches. Is its lack of growth there dueto an absence of seed sources?
Other aspects of Table 2.21 include the importance managed vegetation in formal play areas, gardens,cultivated land parkland near the beaches of Strathclyde (but almost entirely along the Firth of Clyde), andTayside and Fife. The relatively high value in this category for Orkney is a reflection of a number of caseswhere the coastal dune fringe gives way within a few metres landwards to cultivated land.
Areas where there is little by way of the normal long dune grasses in the coastal vegetation is indicated bycolumn 4 (Table 2.21) where 16.8% of all cases are so classified. Shetland, Western Isles and parts of thenorthwest Highlands have above average numbers of these truncated systems.
Trees, in the form of plantations, or small groups of patches of scrub are found as a form of ground coverin many dune, machair and links areas. Extensive tree cover, however, is uncommon in the Highlands andIslands of Scotland. Where they exist, they are often experimental plantings – eg at Dunnet Bay – or naturalcopses of birch and rowan on the margins of the blown sand area – eg Torrisdale Bay. Elsewhere, smallgroups of trees may be found on the landward margin of the blown sand area or as a small copse in asheltered hollow, valley floor or, occasionally, as a shelter belt in the transitional area. Such occurrences arerecorded in Kintyre, Cowal and Arran. More unusual is the patch of willow-dominated vegetation such asis found in dune slacks. Coul Links is one of the better examples of this type of natural scrub association.
In Lowland Scotland, extensive afforestation as well as the presence of relatively large stands of deciduousand mixed woodland are more common. More than 40% of all lowland beach units have some areas oftrees in, or very close to, the dune and links areas. Some distinction has to be made between extensiveconiferous forests – such as Culbin, Burghead Bay, Spey Bay (all in Moray), Tentsmuir (Fife) andRavensheugh (East Lothian) – compared with small coniferous plantings as occur, for example, at Strathbeg(Grampian) or Barry Links (Tayside). Another situation is found at Shell Bay in Fife where an extensiveconiferous plantation lies on blown sand more than one kilometre inland from the beach. Elsewhere there isa range of situations that have been recorded as having trees of some description on the dunes or linksareas. Wooded hillsides adjacent to beaches occur in several parts of the coastline of the Solway Firth andin East Lothian and deciduous woodland is found on the headland margins of some of the beaches of Fife.Planted Sea Buckthorn scrub is found at Tentsmuir and Gullane (East Lothian) and other scrub species are
found associated with most of the beaches between Gullane and Longniddry. Mature deciduous woodlandis found at the beaches west of Edinburgh and in the coastal park at Silversands in Fife. For various reasonsdifferent amounts and types of tree cover occur in many beach areas and give an added dimension to thescenic appearance, to the ecological interest and, in some instances, provide shelter and protection to thedune and links surfaces. Although all stages of the evolution of coastal dunes and adjacent blown sandsurfaces are intimately related to different types of vegetation cover which range from pioneer colonisers ofthe backshore zone to scrub woodland and heath further inland, this survey, as summarised in Table 2.21,has to be confined to broad generalisations.
Plate 1. Aberdeen – an intensively used urban beach.Beaches with high levels of use are relatively rare in Scotland, and are mostly concentrated around the Firth and Clyde coasts.
Plate 2. Traigh Cille Ionnaig, Coll.Numerous beaches in the Scottish islands are almost unused for recreational purposes.
Plate 3. Balmedie, near Aberdeen.The complexity of the dune environment is well illustrated here. Almost all dune elements are represented, from embryo dunes to
various forms of erosion. The effects of small streams on dune topography are also apparent. The dune system merges with a lowraised beach surface.
Plate 4. View from Ben Hough, Tiree.The rocky slopes of the hill lead down to level, enclosed croftland, with unenclosed grazed machair to the seaward of the crofts,
and the fringe of coastal beaches in the middle distance.
3 CHARACTERISTICS AND USE OF THE BEACH RESOURCE
3.1 Accessibil i ty
Accessibility (at a variety of scales) is perhaps the major influence on existing recreational use and the mainconstraint on potential use. If a beach is inaccessible, then its usefulness as a recreational resource isseverely restricted. It may be prized by the seeker of solitude who is able to overcome its remoteness or otherdifficulties of access, but it will have little recreational value for the general public. Conversely, the accessiblebeach is likely to be used intensively for recreation almost irrespective of its other attributes.
Although Scotland is well endowed with beaches, their distribution is quite different from that of populationand recreational demand. More than half of the Scottish beach resource lies on islands, and around 20%of the beaches are on islands lacking regular car ferries (Table 3.1).
Table 3.1 Location of beaches
Number Percentage
Mainland 304 47.0
Islands with car ferry 216 33.4
Islands with passenger ferry only 86 13.3
Islands with no regular ferry 14 2.2
Uninhabited islands 27 4.2
As a result of their distribution at the national scale, a very substantial proportion of the beach resource isinaccessible from the viewpoint of recreational demand. However attractive the island beaches may be,their inaccessibility in terms of cost and difficulty of travel is a major constraint on use. Most of the demandfor beach recreation is met by mainland beaches which number less than half of the total. Beaches are alsounevenly distributed within the mainland. Most of the beaches lie on moderately exposed outer coasts, whilethe main centres of population are on or near estuaries. While the east coast cities are well located forbeach recreation, the main urban centres of west-central Scotland are up to 50km distant from extensivebeaches. The disparity between distribution of population and distribution of beaches is reflected in thelength of travel involved in beach trips. According to Duffield and Long (1977), the average return distancetravelled on a beach trip is 70km, and only 18% of beach trips are under 8km in length. Compared withmuch of England and mainland Europe, however, Scotland’s population has easy access to beaches.
The major arteries of tourism, such as the A74, the A82 and the A9, are distant from coastal beaches alongmost of their lengths, and of the other significant tourist routes, only the A1 and the A75 and the A92 followcoastlines on which sand beaches are common. The distribution of holiday accommodation and its usagealso differs from that of beaches. Of the ten leading tourist locations (in terms of total bednights), only three(Aberdeen, Ayr and St. Andrews) are strongly associated with beaches (Duffield and Long, 1976). Beachesare major and indeed even prime tourism resources in some localities, but not in Scotland as a whole.
Only a small number of beaches are directly accessible by public transport, notably along the Clyde coastand to the east of Edinburgh. Some beaches in Tayside and Fife can be reached by public transport, butin the other regions the use of a private car is almost essential if beach recreation is to be enjoyed.
In Scotland as a whole, a survey in 1972 indicated that 62% of beach trips are made by private car. Busesand trains account for a further 26% (Duffield and Long, 1977). The same survey revealed that, incomparison, 59% of all (day) recreation trips are made by private car and 22% by public transport.It seems, therefore, that beaches and recreational resources in general are approximately equally accessibleby public transport.
People usually do not walk long distances from their cars (or public transport) to recreation sites, and hencethe local aspects of access are important determinants of recreational use. lf the scale of examination isswitched from the national to the local, Scotland’s beaches are found to be surprisingly accessible. Althoughmany beaches are on small islands or in remote, sparsely populated parts of the country, around 40% arewithin 100m of a public road, and over 50% are within 200m. Only 15% are more than 1km from such aroad. These proportions apply to island beaches and to mainland beaches alike. Physical accessibility iseven easier if motorable tracks are considered, irrespective of whether they are public or private.Approximately two thirds of all beaches and over 70% of mainland beaches lie within 100m of motorabletracks and less than 10% are more than 1km from potential vehicular access.
In a few cases the convenience of proximity of road and beach is offset by the vertical distance whichseparates them, culminating in some cases in near-vertical cliffs. Such cases are comparatively few. Morethan three-quarters of the beaches are within 10 vertical metres of the nearest road, and the vertical distanceexceeds 25m in under 10% of the beach units. The position of beaches in relation to roads and tracks istherefore generally convenient from the viewpoint of the visitor, as long as he is able to reach the parts ofthe coastline which contain beaches. For the tourist or casual visitor with no prior knowledge of the existenceor location of beaches, the distribution is less favourable. Almost 40% of the beach units are not visible froma public road, and of the remainder approximately 10% are visible only across sea lochs or straits.Furthermore, the nearest road is frequently a minor dead end carrying only very light traffic, with few touristsor casual visitors. The nearest road type for approximately 40% of the country’s beaches is unclassified orC-class dead-end roads, and A-class through roads are the nearest for only 20% of all beaches.
When the various limitations on accessibility are superimposed, few beaches are found to be well situatedfor casual recreational use. For example, only 41 beaches out of the national total of 647 (6.4%) are 100mor less from A-class through roads on the mainland. Without prior knowledge or information about thedistribution of beaches, the potential visitor is greatly restricted in his choice of recreational beaches. Manyunits which are otherwise suitable for recreational use are little used except where their locations arepublicised by guidebooks or information services.
At the local scale, access to beaches is also influenced not only by location in relation to the roadnetwork, but also by the presence and nature of any barriers to access. One potential barrier is a lack ofcar parking space. Formal car parks are found in the vicinity of 10% of all beaches and 20% of mainlandunits, but cars can be parked informally close to many other beaches. Less than one-quarter of the mainlandbeaches lack car-parking facilities in any shape or form, and in general terms parking problems are foundonly near a minority of beaches. Nevertheless, such problems may be acute in a few localities, especiallyat peak periods when the capacities of formal car parks may be inadequate. Where formal car parks arenot provided, roadside parking may cause traffic congestion at times, and parking restrictions have had tobe applied near some rural beaches (such as Ardneil Bay on the Firth of Clyde) as well as at some townbeaches.
Beaches where cars can be driven almost to the coastal edge are highly valued for informal family recreation,especially where dunes or machair offer attractive settings for picnics. These ‘drive-on’ links or machairs areassociated with approximately 20% of the beaches. On beach car parking can in certain circumstances beeven more convenient than parking on links or machair, but is less practised in Scotland than in somemainland European countries. Where practicable, it offers a convenient solution to some parking problems,and avoids the problems of damage to vegetation which are often experienced as a result of parking on linksor machair. But it may be possible only during low tide, and major problems of safety (especially of children)may arise unless the practice is strictly controlled. Beach parking is carried on at only a small number ofbeaches, such as Culzean Bay south of Ayr and Mersehead Sands south of Dumfries.
Charges for parking are made only at some of the more popular beaches, especially at town beaches whereparking facilities are restricted. Some of the more popular rural beaches have charges during peak periods,but these charges are almost invariably modest, especially in relation to petrol costs, and are unlikely tofunction as a serious constraint on beach use.
Physical barriers to access are found only at a minority of beaches. Cultivated land separates road and beachat less than 10% of beach units, and usually has fences, which are found at approximately one-quarter of thebeaches. Both these types of barriers are mainly to be found in the lowlands, and are rarely encountered nearHighland beaches. Real or perceived barriers, such as buildings and warning notices, exist on less than 10%of the beach units. Whatever the legal position may be, de facto access is possible at all except a fewbeaches. Physical and legal barriers to access are of much less importance in relation to beach recreation thangeographical distribution and location. On the other hand, warning notices and similar deterrents to accessare more prevalent at beaches where accessibility is relatively easy. They are found on only 7% of all beaches,but on 14% of mainland units. Where recreational pressures increase, a few landowners do take steps todiscourage access by erecting notices or locking gates. Such landowners constitute a small minority and ingeneral terms beach access is easy.
3.2 Ownership and tenure
The use and management of beach areas are strongly influenced by the nature of ownership and tenure.Ownership is especially important in relation to recreational use. At low intensities of use, recreation maybe a minor or subsidiary activity which interferes little with the dominant land use and requires little or nomanagement. As recreational intensity increases, the degree of interference with other uses may alsoincrease, and at the least there will almost inevitably be a need for a management commitment.
Detailed and reliable information on land ownership is difficult to collect. The ownership of many beachcomplexes is divided between several individuals and organisations, and various types of formal andinformal letting or leasing arrangements apply. It is important to emphasise, therefore, that the ensuinganalysis of ownership and tenure is simplified and generalised.
Much of the foreshore (the beach below high water mark) is owned by the Crown, while most of the otherparts of beach complexes are under private ownership. The nature of ownership of the foreshore is of limitedsignificance for recreational purposes. Access is rarely prevented, and cleansing of the most visited beachesis usually carried on by the local authority irrespective of ownership. The ownership of the foreshore,however, may be of some significance in relation to the mooring of recreational craft and to sand extraction
or industrial development. In very general terms, there is an inverse relationship between the degree ofdevelopment of the coastline and the proportion of foreshore which is owned by the Crown. This relationshipis perhaps most clearly demonstrated in relation to southwest Scotland, where most of the foreshore inGalloway remains in Crown ownership while most of the foreshore of the Clyde coast is in private hands.The relationship, however, is by no means simple: pockets of privately owned foreshores occur on stretchesof coastline where Crown ownership is dominant, and vice versa.
The ownership and tenure of the supra-tidal parts of the beach complex are of greater practical significancefor land use and management. The distribution of ownership and tenure is indicated in Table 3.2.
Table 3.2 Ownership and tenure (percentage distribution)
All beaches Mainland beaches Island beaches
Private (owner-occupied) 47.0 53.5 41.4
Local Authority 12.3 22.3 3.5
State 6.0 6.0 2.6
Croft 7.6 3.3 12.4
Common grazing 16.3 4.7 28.5
Other tenanted 5.7 3.0 8.2
Other or not known 5.0 7.3 2.9
Private ownership is clearly dominant, in both mainfand and islands, and accounts for just under half of all
beaches. This category is defined as excluding privately owned fand under crofting tenure or leased to a
tenant, but it nevertheless encompasses a wide range of types of ownership. The most common type is that
involving a single owner, where the beach complex lies within a farm or estate. Around three-quarters of the
privately owned beaches are in the hands of individuals, and the remainder are owned by companies or
clubs. Two main types of company may be identified. One is concerned with industrial development or sand
extraction, while the other has interests in tourism or recreation, often in the form of caravan sites or holiday
villages. Both these forms of company ownership are unimportant in terms of national percentages, but at
the local level they may be of some considerable significance. This importance extends both to landscape
effects, which may be considerable, and to broader questions of access. Where industrial development or
the development of commercial tourist facilities occurs, then access for the general public may be restricted
or prevented. A few beaches, mainly in the lowlands, are affected in this way. Access problems are not
confined to company-owned beaches, but the proportion of company-owned beaches where access
problems have arisen is greater than in the case of individually owned areas.
Another sub-category of privately owned beaches is that involving golf clubs. As in the case of the wider
category of privately owned beaches, club ownership of a beach area is usually incidental to the ownership
of adjacent areas such as links. Club ownership achieves its greatest frequency near the outskirts of towns
and cities in the lowlands, especially on parts of the Firth of Forth and Firth of Clyde. De facto access to the
beach is usually possible along the margins of the golf course, but management is understandably geared
to the golf course itself rather than to informal recreation, and problems of trampling and litter have arisen
A sizeable and growing proportion of Scotland’s beach areas is owned by local authorities (see Plate 1).In a few cases, such as Ayr and Aberdeen, the area around the beach has been in municipal ownershipfor centuries, but local-authority ownership began to emerge to a significant extent following the Public Parks(Scotland) Act of 1878. From then until the early part of the twentieth century, the landward parts of severalbeach complexes, especially around the Clyde and Forth, passed into public ownership, to be managedfor recreational purposes. Acquisition was frequently followed by the construction of promenades, gardensand play areas, with low dunes sometimes being levelled off and sown with grass. The landward parts ofmost urban beaches are now under the ownership of local authorities, usually the district councils.
In a few localities, district councils also control a number of rural beaches. Such control is usually related tothe energetic promotion of positive coastal policies on the part of the council (or its predecessor). The mostnotable example is provided by East Lothian. In a few cases, the regional council, as highways andharbours authority, is also involved in ownership, but in such cases the ownership of near-beach areas isusually incidental to the ownership of other land or structures. In a few cases, regional councils own moreextensive areas of beach land, acquired primarily for purposes of recreation. Examples include Dunnet Bayin Caithness, Balmedie in Grampian Region and also Achmelvich and Clachtoll in Northwest Sutherland,where machair land previously under crofting tenure passed into public ownership so that the rehabilitationof eroded machair might be facilitated. Public ownership involving local authorities usually occurs wherethere are high levels of recreational use (see Section 3.6). It became established either during the growth ofcoastal resorts a century ago, or more recently in response to growing recreational pressures during the late1960s and 1970s.
State ownership is less frequent and less closely geared to recreation. A number of state agencies own landaround beaches, including the Forestry Commission, the Nature Conservancy Council and the Ministry ofDefence. State ownership does not always imply easy public access: footpaths and other attractiverecreational facilities are provided on Forestry Commission land at a number of localities, such as BurgheadBay, Tentsmuir and Luce Sands, but ownership by the Ministry of Defence is usually associated with partialor complete prohibitions on access. Such hindrances to access may be significant locally, as for example atBarry-Buddon and the central part of Luce Sands, but are of little importance at the national scale becauseof the very small number of beach units affected.
Just over one-fifth of Scotland’s beaches are under crofting tenure. By definition, such tenure is confined to theCrofting Counties, and is a much more prominent feature in the islands than on the mainland. Crofting tenuremay be sub-divided into croft land and common grazings. The former is usually individually occupied landwhich has been improved at some time and which may be enclosed, while common grazings are usuallyunenclosed rough pasture. Croft land resembles other tenanted land in several respects in so far as recreationaluse and management are concerned. Many crofters have been able to develop caravan sites on their holdingsas, for example, on the Arisaig-Morar coast. The growth of recreational pressures on common grazings, onthe other hand, has sometimes led to persistent and intractable problems. Communal tenure of the land maynot be conducive to initiative in response to changing conditions, and difficulties are usually encountered ifattempts are made to apportion the land to an individual or to resume it out of crofting tenure so thatrecreational developments may proceed. This form of tenure is associated with some of the most fragile anddynamic beach units, and effective management in some cases has been delayed until the areas in questionpassed into public ownership. Again, problems of this type, although severe locally, are not of outstandingsignificance at the national level. Only 8% of the mainland beaches are subject to crofting tenure, and theytend to be located in more remote parts of the country where recreational use is generally light.
Nationally, the patterns of ownership of beach areas change only slowly: the most significant trend over thelast century has been the slowly growing proportion of public ownership, and this trend may well continueinto the foreseeable future. Changes of ownership within the sectors listed in Table 3.2 may be of equal orgreater importance for beach use and management. A change from private ownership where the mainmotive is related to agriculture to one where the main interest lies in tourist enterprises, for example, may beat least as important as a cross-sectoral change of ownership. Over the last twenty years, a number oftransfers of ownership have occurred prior to the development of large caravan sites or holiday villages.Another kind of change which is potentially significant is of the size of the unit of ownership. In somecountries on mainland Europe, the fragmentation of land holdings on the coast, which is often associatedwith the development of holiday homes, has posed severe problems for coastal planning and management.Fragmentation of this type is not at present a serious problem on the Scottish coast, and it may be that thedevelopment-control policies of the local authorities are capable of controlling any problems which mightemerge as a result of tendencies towards fragmentation. But planning and management for the public interestalso inevitably become more difficult if ownership is fragmented into numerous tiny patches, and themonitoring of land transactions in the coastal zone may be a useful adjunct to coastal planning.
An interesting trend in recent years has been the growing use of management agreements. These aresometimes informal and involve little more than an agreement by the local authority to cleanse andperhaps mow small areas of otherwise unused privately owned land between road and coast as, forexample, in Wigtown District. In other cases such agreements are more formalised, and involve both agreater provision of recreational facilities and a greater intensity of management for recreational purposes.Agreements of this type are mainly confined to lowland beaches and are most numerous in East Lothian. Asyet very few access agreements under the Countryside (Scotland) Act) have been negotiated for sandbeaches. While access per se is not a widespread problem, these agreements provide a basis for agreeingarrangements for adequate management, and it seems possible that increased use may be made of themin the future. It is also possible that formal management agreements may become more widely used tools ofcoastal management. If management agreements (whether formal or informal) do become more widelyemployed, the relative importance of landownership in coastal land use and planning may decrease, andrecreational use and management may be accommodated more easily on privately owned coastal land.While public ownership will probably remain essential around the intensively used urban beaches,management agreements may prove to be useful tools on the margins of towns and in the more intensivelyused rural areas.
3.3 Scenic quality
Many of Scotland’s beaches are located in parts of the country where landscape quality is high. More thanhalf of the beach complexes are in the Highlands and Islands which are renowned for their scenery.Although the setting of the lowland beaches may be less spectacular, the lowland coastline is usuallyattractive in its own right, and at the local or regional scale it is a landscape component whose relativevalue is enhanced by proximity to urban and industrial development.
The attractiveness of a beach complex depends on a number of factors. One of these is the beach itself,where an important attribute is sediment composition. Beaches composed of pure sand are often regardedas more attractive than those where sand occurs alongside pebbles or other sediments. The extent of thesand, however, may be relatively unimportant. Very long beaches may lack contrast and visual interest
compared with shorter stretches of sand interrupted or enclosed by rocks. Another important attribute of abeach is the colour of the sand: pale or white sand is probably regarded more favourably than sand of agreyish or indeterminate hue. Pure sand beaches, of a pale colour and enclosed by rocks or cliffs, are foundmainly in the Highlands and Islands, and especially on the west coast of Lewis and Harris, Tiree and otherArgyll islands, and northwest Sutherland. Many of these beaches are composed of shell sand and areassociated with machairs whose bright green summer colours contrast with the greys, browns and duns ofthe surrounding terrain. Likewise these smooth, grassy swards contrast with the rougher textures ofneighbouring rock and bogs. The attractiveness of the contrasts in colour and texture between the beachcomplex and its setting is further enhanced by hilly or mountainous backdrops. Where there is a pronouncedvertical element in the landscape, the scenic quality is often high.
Highly valued elements of beach form, beach materials and setting thus tend to coincide in parts of theHighlands and Islands. The main concentrations of beaches of the highest scenic quality are in west Harrisand southwest Lewis, in northwest Sutherland, and in Islay and Colonsay. In addition, many of the beachcomplexes in these areas are almost untouched by built development. Although they have not totally escapedthe hand of man, they seem to conform to the stereotype of the idyllic, unsullied beach, and their perceivedscenic quality is probably further enhanced by their untarnished atmosphere and remoteness.
But outstandingly attractive beach complexes are not confined to parts of the Highlands and Islands. Mostof the lowlands may lack the amplitude of relief which contributes so strongly to the quality of the setting ofmany of the beaches in the Highlands and Islands, but a setting in a bold cliffline or wooded backdrop mayat least partly compensate. Most of the major sectors of mainland coastline contain highly attractive cliff-footbeaches: in the northeast there are examples such as Aberdour Bay; in the southeast there is Seacliff, andin the southwest Knock and Killantringan Bays. A backdrop of trees may contribute forcefully to atmosphereand scenic quality as well as to shelter. Beaches in wooded settings are rare in Scotland and have a scenicquality of their own. Burghead Bay, Culbin Sands and Littleferry on the east coast combine a backdrop ofconiferous forests with more distant Highland views. In the southwest, Cardoness Shore has an uniquecombination of rock-interrupted sand, a frame of woodland and a backdrop of hills of granite moorland.
Elsewhere, it is noticeable that the Highland beaches where woodland constitutes a strong landscapeelement as in the cases of Gairloch (Wester Ross), Sandaig (W. Inverness-shire) and Dorlin (Moidart) aredistinguished by their high scenic quality. Beaches composed of shell sand and associated with woodlandor mountains are amongst the most attractive visually, especially if these attributes coincide with intricacy ofcoastline and seascapes involving loch, strait and island.
Association with woodland and intricacy of coastline are attributes which are not confined to Scotland:similar settings are found in Scandinavia and Iberia, for example. On the other hand, beaches composedof white shell sand and associated with rich green machair enclosed by hilly moorland are less widelydistributed in Europe, although they are more numerous in Scotland than the woodland type. OutwithScotland, their main concentration is on the Atlantic coast of Ireland. At the international level, therefore, themost distinctive scenic attribute of Scotland’s beaches is that exemplified in the machair beaches of Harris,west Lewis and northwest Sutherland.
Although beach complexes of the highest scenic quality are relatively few in number and are mainly but notexclusively confined to the Highlands and Islands the overall quality is high when judged at a British or
The most frequent form of expression of conservation interest is the notification (to the land owner andplanning authorities) of a Site of Special Scientific Interest. Beaches so classed are widely distributed, butare especially frequent along parts of the outer coast of the Firth of Clyde, the Solway east of Wigtown Bay,East Lothian and east Fife, the Grampian coast between Buckie and Fraserburgh, and in Easter Ross andeast Sutherland. The main effects of this notification are in relation to planning applications, on which theadvice of the Nature Conservancy Council must be sought, and in the specification to the owner or occupierof a range of management operations affecting the scientific interest of the site on which consultation isrequired with the Council. Approximately 9% of beach complexes are in SSSIs classed by the Council asGrade 1 or Grade 2. These key sites are widely distributed, but lie mainly outwith the central belt. Most ofthe major sectors of the coastline have some key sites, but they are rather more numerous on the Solway andMoray Firth coasts than elsewhere.
Beach areas designated as National Nature Reserves (NNRs) are even smaller in number and extent. Lessthan 2% of Scotland’s beach complexes are in National Nature Reserves. The island of Rhum, which isowned by the Nature Conservancy Council, accounts for three of these beaches. Others are widelyscattered from the Monach Isles and part of South Uist in the west to Tentsmuir and Forvie in the east. Wherethe NNR is under the ownership of the Nature Conservancy Council, management may be solely orprimarily for purposes of nature conservation, but in the cases of NNRs in private ownership the sites areusually subject to management and use for a number of purposes of which nature conservation is only one.A number of nature reserves have been established by voluntary bodies, such as the Scottish Wildlife Trustand the Royal Society for the Protection of Birds. Examples involving beaches include part of the Loch Fleetbeaches and Handa in Sutherland, and Horse Island in the Firth of Clyde.
The safeguarding of key sites for biological conservation has been furthered in recent years by thepreparation of the Nature Conservation Review. Parallel work on the Geological Conservation Review,which deals with sites of geological and geomorphological interest, is as yet incomplete. It is very probable,however, that several Scottish beach complexes will rank amongst the key geomorphological sites. Beachcomplexes are amongst the most dynamic of geomorphological systems, and for this quality their scientificinterest is often high. Such sites include outstanding examples of coastal landforms and also areas wherethe physical processes involving beach, dune and machair are highly dynamic. These sites offeropportunities for studying the forms and rates of development of beach complexes. As well as being ofintrinsic scientific interest, such research is also likely to be productive for the management and use of beachcomplexes. Examples of beach complexes which are of outstanding geomorphological interest include theMorrich More (Easter Ross), Invernaver (North Sutherland) and parts of the western seaboard of Uist in thenorth and west of Scotland, as well as Strathbeg and Forvie (both in the vicinity of Peterhead), Tentsmuir(near St Andrews) and Luce Sands (near Stranraer) in the east and south. These sites are distinguished bytheir extent, complexity and dynamism. It is noticeable that many of them are also outstanding for thebiological interest. This coincidence is not the result of pure chance; the variety of component parts in thegeomorphological assemblages of the outstanding beach complexes supports a rich diversity of habitats.
Because beach complexes tend to be dynamic in nature, questions may arise as to the desirable level ofmanagement for conservation; if a feature is undergoing rapid (natural) change, is the goal of managingchange a desirable one? But if change extends to a state of degradation, the end result may be a wideextent of bare and sterile sand which may be of little value for any use. In many cases, therefore, long-terminterests in practical land use and nature conservation may coincide.
Beach complexes are used for a wide variety of purposes. Some recreational use is made of almost everybeach in the country, as will be discussed more fully in Section 3.6. In some cases, the intensity ofrecreational use is such that it is the primary or even the sole use as, for example, in the resort beaches ofthe lowlands. It is more usual for recreation to co-exist with agriculture or other uses of beach complexes, atleast in their landward parts.
Grazing
Grazing is by far the most widespread of the non-recreational uses and occurs at almost every blown-sandarea in the Highlands and Islands and at over two-thirds of all the beach complexes in Scotland. The pattern,form and impact of grazing vary from place to place. In general terms, the more remote or inaccessiblemachairs are grazed by sheep only and are subject to little direct management. In many instances, themachair grazings are not physically enclosed from the surrounding rough grazings and grazing pressureson the sweet machair grasses may be high although overall the local grazing intensity is low. Many machairsin the Highlands and Islands form parts of common grazings. Grazing usually occurs the whole year round,but in some cases where the machair is close to the township it is confined to the winter half of the year.Cattle grazing occurs in over half of all beach complexes and over 60% of those with dunes, links ormachairs. It tends to be associated with rather less remote areas than those subject only to sheep grazingand it is relatively most important in areas such as Orkney, parts of the Argyll islands and the Clyde coastas well as on some of the more rural beach complexes on the east coast. Cattle grazing is less stronglyassociated with crofting tenure than sheep grazing, and it is usually found on links held as part of owneroccupied or tenanted farms. The areas so used are usually fenced and subject to greater management inputsthan in the cases where there is extensive sheep grazing.
Most machairs and many links have been subjected to grazing for many decades and probably forcenturies. The ubiquity of the practice is such that its significance is difficult to assess in light of the paucityof ungrazed beaches which may be used for comparison. It is usually assumed that grazing is likely toreduce the stability of vegetated blown sand by reducing vegetation cover. Its significance depends on thesetting and dynamism of the beach complex and on its intensity and duration. Light seasonal grazing has alesser effect than intensive year-round grazing. Secondary effects of treading, trampling and rubbing bygrazing animals may be as significant as the primary effect of grazing itself and, in particular, such effectsmay help to perpetuate small blow outs or areas of bare sand by preventing or delaying revegetation.
In general terms, the magnitude of grazing effects is probably greatest on a number of heavily grazedmachairs lying within common grazings on parts of the northwest mainland and Western Isles. In thesecases, the machair sward is often closely trimmed and presents little barrier to sand blow. Rubbing andburrowing by sheep on deflation faces on these machairs detract further from their stability. The main effectsof grazing by cattle, on the other hand, are probably found on the landward slopes of dunes to which theyhave access. Combinations of grazing and trampling may tend to suppress marram and, depending on siteand intensity, may hasten the development of vegetation resembling that of links, or create bare sandpatches. Rabbits also have both physical and botanical effects. Patches of bare sand around their burrowsmay be exploited by wind erosion and, on machairs where rabbit densities are high, there may be a shiftin the floristic composition such that Ragwort (Senecio jacobaea), a species unpalatable to rabbits anddomestic stock, becomes locally dominant.
Grazing is probably a major environmental factor and has probably been so throughout historical times. Asyet, little quantitative information is available about its effects on the blown-sand environment, and littleexperimental work has been undertaken. Recently, some experimental work on grazing effects has beencarried out at machair sites as part of the Beach Management Project run by the Countryside Commissionfor Scotland (CCS 1978), and it is hoped that this work can be continued and extended so that thesignificance of grazing on blown-sand substrates may be more fully assessed. Conservation of grazings onlinks and machairs is a desirable goal from a number of viewpoints, and especially from the agriculturalone. In the north and west, the lime-rich machairs are usually of much higher grazing value than thesurrounding acid moorlands, while in other parts of the country the free drainage and shelter associated withmany dunes and links are useful assets for the wintering of cattle. Grazing use will probably continue to bethe major use of beach complexes in the foreseeable future and, for this reason quite apart from any others,there is a need for a fuller understanding of its effects on the dynamics of dunes and machairs and for moreexperience of appropriate management regimes.
Cultivation
Although blown sand is not inherently fertile and may pose problems of drought and erosion on cultivation,just over one-quarter of the country’s beach complexes are under cultivation in some form and to some extent.In relative terms, the importance of cultivation is probably greatest in areas such as the Uists and Tiree, whereextensive machair plains have for long been cultivated for cereals and root crops. Cultivation in these areaswas formerly geared mainly towards the production of crops for human consumption, and for many centuriesmachair soils were valued for their lightness and ease of cultivation as compared with neighbouring areasof peaty moorland or rocky ground. Cultivation has contracted markedly even in the relatively short periodsince the Second World War and is now geared largely towards the production of fodder crops, althoughpotatoes are still grown. Cultivation on Hebridean machairs is usually confined to small patches on themachair plain, and the location of these patches may shift from year to year.
The form and characteristics of cultivation on most mainland beach complexes differ in several respects. Thetypical site of cultivation is a raised beach where marine sediments are veneered with blown sand. Theraised beach usually takes the form of a gently sloping bench not exceeding a few hundred metres in widthbetween an old cliffline and the shore. Where the raised beach occupies a narrow bayhead or where it isinaccessible to agricultural machinery, its use may be confined to grazing, but where it is more continuousand more accessible, it is often given over to the production of barley or early potatoes. This kind ofcropping is characteristic of parts of the coastlands of southwest Scotland and is perhaps best developedaround Girvan. On the east coast, where depths of blown sand on the raised beach are sometimes greaterand the soils are excessively dry, cultivation is less extensive.
Cultivation usually precludes other land uses and is of some significance for recreation. Cultivated land isusually enclosed by fences (at least outwith the Uists) and presents an obstacle to beach access. In particular,it may tend to exclude the casual camping or caravanning which is often encountered on unenclosed linksor machairs.
Extraction
Extraction of sand or aggregate takes place on approximately one-fifth of Scotland’s beach complexes. Thesite of extraction may be on the beach itself or on blown-sand deposits. In general terms, sand extraction ismore common on island beach complexes than on the mainland. Some of the more accessible units on the
major islands have been heavily exploited for sand which has been sought both for agricultural purposesand as a building material. The level of use of shell sand in land reclamation and reseeding work hasfluctuated in recent decades, but the taking of sand for building material has increased in some localities inaccordance with demand from oil-related developments. Large scale sand extraction is principallyassociated with some beach complexes in Orkney, Shetland and, to a lesser extent, Lewis. It is not confinedto the more distant islands, however, and some beaches on the Clyde coast (for example Brodick andGirvan) and elsewhere have been seriously affected. If extraction rates from the beach exceed natural ratesof sand supply, the taking of sand is likely to lead to accelerated erosion of the coastal edge. Extractionfrom pits in dunes or machair may avoid this problem, but this can result in unsightly and possibly dangerouspits and perhaps in modifications to the water table. Extraction pits are sufficiently large or noticeable to beregarded as adverse features on approximately 16% of all beach complexes, as Table 3.3 indicates.
Table 3.3 Extraction pits as adverse features
Beach complexes (percentages)
All Mainland
Absent 84 88
SeverityLow 10 9
Present: Medium 4 2High 2 1
Although the number of beach complexes seriously affected by extraction may be relatively low, the effectsare usually of major significance. The taking of sand or aggregate may lead to irreversible changes in thebeach environment and, unless matched to natural rates of sand supply (which are seldom known withprecision), is a damaging use which inevitably leads to the consumption of the resource. In the long-term,sand extraction from dunes and machair is incompatible with most other uses and it is of particular concernsince it is usually the most accessible beach units which are so affected.
Industry
Industrial land use is confined to around 4% of Scotland’s beach complexes. In the few cases where itdoes occur, its practical importance in relation to landscape and other uses may be disproportionately large.At a few localities, industrial plant dominates the beach unit visually to the detriment of the quality ofthe recreational environment, and in others almost the whole of the landward part of the beach complexis occupied by factories or similar buildings. The industrial use of beach complexes is stronglyconcentrated along short stretches of coastline on the Clyde and Forth coasts and at Aberdeen. Recreationaldemand in these areas is high because of the large local populations. A wide range of types of industryis found on beach complexes, but chemical and fertiliser plants are prominent, often associated withlarge structures which cannot readily be landscaped, and in some instances with smoke or other formsof pollution.
Military use
Military use occurs in 3% of the country’s beach units. This type of use usually precludes recreation and other
forms of land use, but it is unusual for a whole beach complex to be reserved for military purposes. Beach
complexes in military use tend to be larger than average and some of them are of outstanding scientific interest.
Examples include the Morrich More on the Dornoch Firth which is used as a bombing range, and Luce Sands
in Wigtown District which is used for bombing and weapons training. Other examples are Black Dog near
Aberdeen and Barry Buddon near Dundee, both of which are firing ranges. The degree of impact arising from
military use varies considerably. m e amount of earth moving and other changes effected on firing ranges is
usually fairly slight, but at Luce Sands large expanses of dune terrain have been levelled and grassed over in
order to facilitate the retrieval of weapons. Several other beach complexes, such as Irvine Bay at Dundonald,
were formerly used for military purposes and, although there is no longer a military presence, the signs of
military use, in the form of buildings and other structures, are still visible.
Table 3.4 Industrial and mili tar y installations as adverse features
Beach Complexes (percentages)
All Mainland
Absent 90 83
SeverityLow 6 10
Present: Medium 1 2High 3 5
Table 3.4 indicates the proportion of beach complexes judged to be adversely affected by industrial ormilitary installations. The proportion is higher than the occurrence of present-day industrial and military usewould suggest and it is clear that the mainfand beaches, where accessibility is easiest and recreational valuegreatest, are disproportionately affected.
Forestry
Commercial forestry is practised at only a few beach complexes, notably on the south shores of theMoray Firth and at Tentsmuir (Fife). The extensive plantations at these localities date mostly from the inter-war period and, at sites such as Culbin, afforestation was carried out in an effort to stabilise mobile sanddunes. Most forests on beach complexes are under the ownership of the Forestry Commission, but a few,such as at Shell Bay in Fife, are under private ownership. Like military use, forestry is usually associatedwith large beach complexes where there are extensive dunefields. On the other hand, forestry rarelyexcludes recreational use and, indeed, positive provision of picnic sites, car parks and other recreationalfacilities has been made in state forests at the coast. In some instances, the attractiveness of thebeach environment has been enhanced by afforestation which has resulted in a type of beach setting whichis rare in Scotland compared with some other parts of Europe (see Section 3.3) and mobile dunes havebeen stabilised. Care will be required when felling begins because dune grasses have generally beenexcluded under the shade of dense forest canopies and unprotected sand surfaces will be susceptible towind erosion.
Other aspects of land use
Various other land uses, although usually confined to very small areas, may have significant effects on the
beach environment. The tipping of refuse or rubble is carried on in about 20% of all beach complexes.
*These figures exclude participants in activities such as golf: they relate to numbers taking part in informal recreationon the beach or in its immediate vicinity. They also relate to good summer weather.
As might be expected, the patterns of recreational use for all beaches differ from those of the mainlandbeaches only. Almost one third of Scotland’s beaches are estimated to have fewer than five visitors per dayin summer. Compared with England and much of mainland Europe, both the proportion and absolute numberof almost unused beaches are high. In this respect, Scotland may resemble lreland and Norway, but on theEuropean scale this pool of almost unused beaches, which in some cases may be regarded almost aswilderness beaches, is a rare asset. The majority of almost unused beaches are on the islands, especiallyon the smaller islands which lack car ferries and other means of easy access. Of the others, several are inthe more remote and inaccessible parts of the Highlands, but most other parts of the country have occasionalexamples (see Plate 2). The main concentration is on the south shore of the Moray Firth, and the group thereincludes both a few long beaches, such as Whiteness Head, and smaller cliff-girt units, such as Findlaterand Whyntie Head. Beaches in the lowest category of intensity of use are almost invariably some distancefrom roads, and they are usually small and little publicised. In a few cases, access is prevented by militaryuse or for other reasons, but in most cases there are no barriers to access if the visitor is prepared to walksome hundred metres from a public road. Those who do so will usually be rewarded by the privacy affordedby the absence of other recreational parties and by a beach environment on which the hand of man hasfallen relatively lightly.
Most of the beach units estimated to have in excess of 500 visitors per day during peak season are closeto urban areas. The major concentration is on the east side of the Clyde coast and on parts of the Firth ofForth and Solway, where they are associated with large caravan sites and holiday villages. The most usedbeaches in the Highlands are near major resorts, such as Dornoch, Oban and Nairn, or close to busyroadsides or large caravan sites in rural areas such as Wester Ross. The most used beaches are all on themainland, except for two cases on Bute and Cumbrae which closely resemble their counterparts on theneighbouring mainland coast of the Firth of Clyde. At peak periods many of the most used class of beacheshave visitor numbers well in excess of the lower class limit of 500. Beach populations at localities such asAyr may reach three or four thousands, and the duration of high usage, on both the annual and diurnalscales, is often much longer than on more lightly used units. Esplanades and promenades on the main urbanbeaches attract recreational use far into the evening and there is also a much higher level of winter use thanin most rural beaches. Although no figures are available on daily totals at beaches, it may be speculatedthat the most heavily used beaches have visitations that are at least four orders of magnitude higher than atthe least used class. In terms of annual numbers of visitors, figures range from over 100,000 at some townbeaches to a mere handful at some remote island units.
Between one-quarter and one-third of the mainland beaches are estimated to fall in the next class of beaches(101–500 visitors per day) compared with only one-seventh of all beaches. The majority of beaches in thisclass are on the Clyde and Forth coasts, but there are also others in less populated parts of the Highlandsand in such cases there is usually a strong association with easy accessibility or with caravan sites. Fortyper cent of mainland beaches are estimated to receive over 100 visitors per day, as compared with 21%of all units. Conversely, around one-quarter of mainland beaches are estimated to have fewer than 26visitors per day, compared with approximately half of all units. The strength of the relationship betweenaccessibility and intensity of use is illustrated in Table 3.6 where estimated day recreation class is crosstabulated against distance from public road. The table relates to all beaches, including those on islands.
Approximately 10% of all beaches have been provided with some forms of recreational facilities, such asshelters, putting greens or play areas. These facilities are associated mainly with urban beaches and in mostcases such provision has existed in some form for several decades. There is a strong degree of correlationof this kind of facility with the most heavily used beaches, but some of the beaches which have becomeheavily used in the post-war period – for example, some of the intensively used Highland beaches – do nothave a typical set of urban beach facilities.
Table 3.6 Estimated day recreation (visitors per day)
No. of Distance from public roadVisitors Under 100m 100–1000m Over 1000m
0–4 21 30 46
5–25 16 24 30
26–100 32 28 18
101–500 20 14 4
Over 500 11 3 1
(Figures are percentages of beaches in each class)
Almost all the more heavily used units have been provided with basic services, such as toilets and litter bins.Approximately one-quarter of all units have the former facility and over one-third the latter. While thesefacilities have been available in most urban beaches for many years, their provision outwith the main resortshas been mainly during the 1960s and 1970s. Litter bins may be provided cheaply, but the constructionand maintenance of toilets are often the most costly items of expenditure in rural beach management.
Like informal day recreation, caravanning and camping are carried on in varying forms and at varyingintensities. Licensed sites for static or touring caravans have been developed on some beach complexes,while caravanning at other beaches is on a casual basis with no provision of facilities. Some form ofcaravanning takes place on approximately 20% of beach complexes. In just over half of these cases,licensed sites have been developed. Static caravans account for the greater part of the capacity of theselicensed sites, but most of them also cater for touring vans. Approximately 30% of the licensed beach siteshave approved capacities of 30 or fewer units and almost two-thirds may accommodate up to 100caravans. On the other hand, there are several large caravan sites with capacities of over 300 units, andone can take up to 600. Most of the large sites are in the lowlands, especially on the Clyde coast wherestatic caravans offer a sizeable amount of self-catering accommodation close to beaches. Parts of the coastsof the Moray and Solway Firths are also characterised by large licensed sites.
Some unlicensed sites are still in operation, but most of the caravanning which takes place outside licensedcaravan parks is in the form of so-called wild caravanning, where few if any facilities are provided. Wildcaravanning is not a major problem in the beach and dune areas of Scotland. It can be a problem locally(especially on some islands) where there is a degree of tourist pressure but an apparent lack of approvedcaravan facilities. The main adverse impart of such use is vehicle tracks, which in a very few cases havebeen exploited by wind erosion. It appears that most of the areas exploited for casual camping andcaravanning are either under-utilised by other forms of land use or lack close contact or supervision.
In recent years, a number of chalet developments have been located on beach complexes, althoughdevelopment control policies have been generally restrictive, as with caravan sites. The number of beachcomplexes that have been affected by chalet developments is small and siting is often confined to thelandward margins of the beach complex. On the other hand, some of the beaches on the Clyde and Forthcoasts and in parts of Galloway have holiday huts or shacks dating back to the 1930s. These are sometimeslocated in conspicuous positions close to the coastal edge, and in some cases have fallen into seriousdisrepair. In the majority of cases, these shacks predate planning controls and the problem which theyconstitute in the beach landscape cannot easily be resolved.
Although the Scottish coastline has not been without problems arising from the development of caravan sitesand similar holiday accommodation, these problems have usually been on a relatively small scale and haveusually been localised along a few parts of the coastline. For the most part, Scotland has been free from thepressures that have led to the development of extensive coastal caravan sites along parts of the coastline ofEngland and Wales. In a few parts of the country, most of the accessible beaches may have beendeveloped to some extent for caravanning, but these developments are rarely continuous and arecomplemented by long stretches of undeveloped beaches along other parts of the coastline.
One of the most common elements of land use on beach complexes in the lowlands and in some parts ofthe Highlands is the golf course. Golf courses exist at approximately 12% of beach complexes. Many milesof coast are occupied by golf links whose typical setting is the lower part of the dune backslope and thepost-glacial raised beach. Golf links are especially frequent on the east side of the Firth of Clyde and onthe south side of the Firth of Forth, as well as in parts of Angus and on the coast north of Aberdeen. Thestandard and levels of management are usually high, and potential threats to stability, such as rabbits andincipient blow outs, are usually checked quickly. But the seaward part of the foredune ridge is usually outwiththe golf course and receives less management although it may be subject to considerable levels ofrecreational use. The typical setting of a links golf course is on the outskirts of a resort or other town. Thetown beach may be used intensively for recreation, but is also intensively managed for that purpose, usuallyby the district council. Towards the outskirts of the town, intensity of management often decreases morerapidly than intensity of recreational use, and symptoms of recreational pressures, such as litter and tramplingdamage, become all too apparent. In localities where these pressures are high. it may be worth consideringwhether access agreements or similar measures could be of value in ensuring both the protection andcontinued use of the beach environment.
Like other land uses carried on in beach complexes, recreation has an impact on the beach environment.The impact is usually stronger on the coastal edge and on the blown-sand deposits than on the inter-tidalbeach and backshore. Although recreational pressures may exert some effects on the beach fauna, and mayalso be manifested in litter, these effects are usually either of a lesser intensity or, alternatively, are more easily
remedied than those exerted on the landward part of the beach complex where damage resulting fromtrampling is often a noticeable symptom of recreational pressure. The environmental impacts of recreationare difficult to quantify, but an indication of their magnitude may be obtained by scoring their occurrenceon a presence/absence basic and, where present, by further scoring according to low, medium or highseverity. The results of this assessment are illustrated in Tables 3.7 and 3.8.
Table 3.7 Trampling damage
Beach complexes (percentages)
All beaches Mainland beaches
Absent 48 25
Low 30 35Present: Medium 16 26
High 7 15
Table 3.8 Lit ter
Beach complexes (percentages)
All beaches Mainland beaches
Absent 46 21
Low 37 47Present: Medium 15 26
High 3 6
From the tables, it is clear that the environmental effects of recreational use are widespresd and occur tosome extent on most of the mainland beach complexes. The effects become apparent when levels ofrecreational use cross very modest thresholds, but intensity of recreational use is not the only variable whichinfluences them. A key factor is the standard and type of management and, in particular, the provision ofpaved surfaces near the coastal edge. The construction of a seawall and access steps protects the mostvulnerable part of the beach complex which, in the absence of protection, may undergo severe deteriorationwith moderate levels of recreational use. Many of the most intensively used beaches are equipped withdurable access points and benefit from efficient systems of cleansing and litter collection, but the conditionof the flanks of these beaches and of beaches where recreational use has increased sharply during the lasttwo decades may be less satisfactory. Suburban beaches and those in easily accessible rural areas muchvisited by holiday makers may be identified as the main locations suffering from environmental problemsarising from visitation. In the case of the former, most of the trampling damage results from pedestrian use,aggravated in a few instances by motor cycles, whilst in the latter cars and caravans may be at least partlyresponsible. Burnt patches resulting from picnics or barbecues are frequently found in both settings, and areoften associated with cans and broken glass. While the control of incipient blow outs and the removal oflitter and debris is relatively easily achieved in the settings and management structures of urban beaches,they are more difficult to organise for suburban and rural beaches. In some instances, a ranger service hasbeen provided (for example, at Yellowcraig and Balmedie), but all too often the heavy recreational use towhich many suburban and rural beaches are subjected takes place in partial managerial vacuum. Changesin land ownership or control and land management have tended to lag behind changes in land use. Theselags occur both where informal recreational use has been superimposed on pre-existing land uses, such as
grazing, and where recreational use has been initiated on narrow coastal-edge strips fenced off fromimproved farmland and previously unused for any purpose. This type is more common in the Lowlands thanin the Highlands and perhaps poses even greater problems than the former. In the absence of clearly definedownership, use and management, the coastal-edge strip may quickly deteriorate with the dumping of refuseas well as the onset of recreational pressures. While it has been demonstrated that some of these strips canbecome useful, cheaply managed recreational assets (for example, in Wigtown District), their potentialusefulness has not always been fully realised and reflected in positive management for recreational purposes.
Countryside Commission for Scotland (1978). Highland Beach Management Project.
Duffield, B.S. and Long, J. (1976). Series No. 3. The holiday-maker in Scotland. T.R.R.U. Res. Rep. 19,Univ. of Edinburgh.
Duffield, B.S. and Long, J. (1977). Series No. 5. Patterns of Outdoor Recreation in Scotland. T.R.R.U.Res. Rep. 25, Univ. of Edinburgh.
Godfrey, P.J. and Godfrey, M. (1972). A comparison of ecological and geomorphological interactionsbetween an altered and unaltered barrier island system in North Carolina. in Coastal GeomorphologyD.R. Coates (Ed.) Binghampton. pp. 239–258.
Mather, A.S. and Ritchie, W. (1977). The beaches of the Highlands and Islands of Scotland. CountrysideCommission for Scotland.
Ritchie, W. (1976). The meaning and definition of machair. Trans. Bot. Soc. Edinburgh, 42, pp. 431–440.
Ritchie, W. (1981). Environmental aspects of oil and gas pipeline landfalls in northeast Scotland. Proc. 17thCoastal Eng. Conf. (1980) Am. Soc. Civ. Eng. III, pp. 2938–56.
Method of wind analysis as used to produce wind roses in Figure 2.4
The method of wind analysis used involves the computation of the direction and relative amount of regionalaeolian sand drift from surface wind data. The approach was suggested by Bagnold (1951) and developedby Fryberger (1979). Winds are evaluated and defined in terms of potential for sand movement by applyinga weighting equation to routine percentage frequency of speed and direction data as provided byMeteorological Office Summaries. The weighting equation has been derived from a modification of theLettau expression to calculate the rate of sand drift from known shear velocities.
q.g/c”p = V* (V*–V*t) (1)
q = rate of sand driftg = gravitational constantc” = empirical constant based on grain diam.p = rho/density of airV* = shear velocityV*t = impact threshold velocity, or minimum shear velocity required to keep sand in saltation.
Additionally C” = C’ (d/d*)n
C’ = universal constant for sandd = mean diam. sand movedd* = 0.25mm (standard size) andn = empirical constant approx. equal to 0.5
Surface conditions, in addition to shear velocity, control the rate of sand drift. These include mean graindiameter, degree of surface roughness, amount and kind of vegetation cover and amount of moisture in thesand. Evolution of these parameters for a large number of localities would be impractical therefore windenergy at various places can be calculated initially using relative quantities of potential sand drift.
This gives a threshold velocity of 11.6 knots which falls into the 11–16 knot speed category onMeteorological Office Summaries.
Having made these assumptions equation 2 can then be used to produce a number which expresses therelative amount of sand potentially moved by the wind during the time it was presumed to blow – ie actualrates of sand drift cannot be predicted but the method can be usefully employed in regional comparison interms of available wind energy.
By substituting values for equation 2 for each of the wind speed classes weighting factors for each speedclass can be derived. This is illustrated for the lower speed classes used in this method of analysis.
Wind summary Mean velocity V2 (V-Vt) V (V-Vt/100*velocity category
11–16 13.5 182.3 1.5 2.7
17–21 19.0 361.0 7.0 25.3
*numbers divided by 100 to reduce weighting factors to smaller size for convenience of plotting wind roses.
The weighting factors thus represent the rate of sand transport while the % of wind occurrence in thesummaries represents the length of time that the wind was presumed to blow from a given direction at agiven speed, therefore, –
Q � V2 (V Vt)t (4)
t = time wind blew, expressed as a percentageQ = annual rate of sand drift
To evaluate the potential relative sand drift at a station the weighting factor for each speed class is multipliedby its percentage frequency for each direction. This is illustrated from the Leuchars Summary for the lowestspeed class:
Method of computing potential sand drift from percentage frequency wind data using weighting equation(Leuchars Annual Summary 1962–77)
The amount of potential sand drift for each direction from all speed classes can then be summed and a totalfor each direction produced. These totals can be used to construct a circular histogram or sand rose whichwill represent graphically both the amount of potential sand drift and its directional variability from the twelvecompass directions used in the Meteorological Office Summaries. The arms of a sand rose are proportional
in length to the potential sand drift from a given direction. The arms point toward the direction from whichsediment moved.
Vector unit totals from the different directions can be resolved into a single resultant – referred to as theresultant drift direction (RDD). This represents the direction to which sand would tend to drift under thecombined influence of winds from the different directions. The magnitude of this direction can be found usingPythagorean theorem and is referred to as the resultant drift potential (RDP).
REFERENCES
Bagnold, R. A. (1951). Sand Formations in Southern Arabia Geographical Journal 117, pp. 78–86.
Fryberger, S. (1979). Dune Forms and Wind Regime, in E. McKee (ed.) A Study of Global Sand SeasUSGS Prof. Paper 1052.
This appendix was kindly provided by Maralyn Robertson-Rintoul.
