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Applied Geography (1992)) 12,319-338 A structured method of landscape assessment and countryside management Alan Cooper and Ronald Murray Department of Environmental Studies, University of Ulster, Coleraine, Co. Londonderry, BT52 ISA, Northern Ireland Abstract A structured method of landscape assessment is described, based on multivariate land classification. Initially the study area is partitioned into geographical units with similar land class characteristics. This is followed by field survey to define unit evaluation criteria using landscape elements that can be described as physical attributes. Following evaluation, resource survey of a stratified random sample of grid squares from land units provides information that can be used for baseline monitoring and countryside management prescription. The resulting database provides a practical summary of the distribution and management of resources in specific localities. The assessment method links the description, classification, analysis and evaluation of landscapes in a structured way and provides a cost-effective, integrated framework within which land use management decisions can be made. Landscape assessment, the process of describing, analysing and evaluating landscapes, is relevant to a wide range of rural planning and management issues, particularly those relating to the use of land for agriculture, forestry, conservation and amenity. However, a review of assessment techniques undertaken by the Countryside Commission (1988) concluded that there was a lack of clear direction from recent academic research or practical studies and that there was disillusionment about the appropriateness and cost efficiency of quantitative methods, particularly those involving a computing or statistical approach. The Countryside Commission also expressed the view that there was growing interest in structured methods of landscape assessment, where techniques are clearly defined and can therefore easily be repeated. Coppock (1980) called for a similar approach to land assessment, proposing that it should be objective, repeatable and practicable and that when judgement needed to be exercised, the choices should be defined by explicit rules based on quantitative measures. A land classification technique that can be applied to structured landscape assessment has been developed by Bunce et al. (1983). This classifies sample kilometre grid squares using map attributes related to climatic, geological and physical variables. The land classes have since been employed extensively as a sample stratification for ecological and land use studies. The main applications have been in describing and monitoring change and assessing the potential for change in landscape elements (Bunce et al. 1983). These applications reflect the requirement of regional planners for information on environmental resources. When supplemented with field data on physical, biological and land use characteristics from sample squares, the land classes can act as a framework for describing landscape types. Application to landscape evaluation studies has been 0143-622819210410319-20 0 1992 Butterworth-Heinemann Ltd
Transcript
Page 1: A structured method of landscape assessment and countryside management

Applied Geography (1992)) 12,319-338

A structured method of landscape assessment and countryside management

Alan Cooper and Ronald Murray

Department of Environmental Studies, University of Ulster, Coleraine, Co. Londonderry, BT52 ISA, Northern Ireland

Abstract

A structured method of landscape assessment is described, based on multivariate land classification. Initially the study area is partitioned into geographical units with similar land class characteristics. This is followed by field survey to define unit evaluation criteria using landscape elements that can be described as physical attributes. Following evaluation, resource survey of a stratified random sample of grid squares from land units provides information that can be used for baseline monitoring and countryside management prescription. The resulting database provides a practical summary of the distribution and management of resources in specific localities. The assessment method links the description, classification, analysis and evaluation of landscapes in a structured way and provides a cost-effective, integrated framework within which land use management decisions can be made.

Landscape assessment, the process of describing, analysing and evaluating landscapes, is relevant to a wide range of rural planning and management issues, particularly those relating to the use of land for agriculture, forestry, conservation and amenity. However, a review of assessment techniques undertaken by the Countryside Commission (1988) concluded that there was a lack of clear direction from recent academic research or practical studies and that there was disillusionment about the appropriateness and cost efficiency of quantitative methods, particularly those involving a computing or statistical approach. The Countryside Commission also expressed the view that there was growing interest in structured methods of landscape assessment, where techniques are clearly defined and can therefore easily be repeated. Coppock (1980) called for a similar approach to land assessment, proposing that it should be objective, repeatable and practicable and that when judgement needed to be exercised, the choices should be defined by explicit rules based on quantitative measures.

A land classification technique that can be applied to structured landscape assessment has been developed by Bunce et al. (1983). This classifies sample kilometre grid squares using map attributes related to climatic, geological and physical variables. The land classes have since been employed extensively as a sample stratification for ecological and land use studies. The main applications have been in describing and monitoring change and assessing the potential for change in landscape elements (Bunce et al. 1983). These applications reflect the requirement of regional planners for information on environmental resources. When supplemented with field data on physical, biological and land use characteristics from sample squares, the land classes can act as a framework for describing landscape types. Application to landscape evaluation studies has been

0143-622819210410319-20 0 1992 Butterworth-Heinemann Ltd

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320 A structured method of landscape assessment and countryside management

limited but it has been shown that land classes in the English Lake District relate strongly to visual information on landscape character (Bunce and Smith 1978).

This paper reports on the application of a structured method of landscape assessment based on the techniques of Bunce et al. (1983) and assesses its value in a study of resource management in the Sperrins and North Derry regions of Northern Ireland. Work began as a pilot study (Cooper and Murray 1987a) in the Mourne Area of Outstanding Natural Beauty (AONB). The survey employed multivariate land classification (Bunce et al. 1983) to stratify a grid square sampling programme within which full cover field survey was carried out to record land use, ecological resources and landscape attributes. In a later study of the Antrim Coast and Glens AONB (Cooper and Murray 1987b), the techniques were modified to integrate field data recording methods with computer database analysis.

The main objective of the Sperrins and North Derry study was to develop a method of landscape evaluation that could be integrated with environmental resource survey methods to give a structured approach to landscape assessment. A second objective was that the assessment should be of practical value to landscape managers. Application to AONB redesignation procedures and the prescription of land management strategies being carried out by the Countryside and Wildlife Branch (CWB) of the Department of the Environment for Northern Ireland (DoENI) was an integral part of the work (DoENI 1988, 1989).

The Sperrins and North Derry regions were first designated as AONBs in 1968 under the Amenity Lands (NI) Act (1965). Their boundaries were agreed by academics and professionals following consultation with the Ulster Countryside Committee, a statutory advisory body set up under the Amenity Lands Act. Changes in the legislation relating to the countryside were introduced with the Nature Conservation and Amenity Lands (NI) Order (1985), following implemen- tation of the Wildlife and Countryside Act (1981) in Great Britain. These changes enabled the CWB to begin redesignation and boundary review procedures and to develop management policies.

The assessment procedure used here consists of a number of stages, each of which is subject to review. At each stage, the criteria on which decisions are made are specified. Following an initial subjective selection of a study area, multivariate land classification provides the basis on which landscape description, resource survey and landscape evaluation are carried out, using information derived from desk studies, reconnaissance field survey and more detailed field survey of sample grid squares. The hierarchical nature of the land classification and the structured approach to assessment mean that field data can be used to develop both regional strategies of landscape management and local management guidelines.

Land classification and landscape evaluation

Circumscription of the study area

The study area was selected by professional consensus following discussion with the CWB (DoENI) so as to cover an area larger than the existing Sperrins and North Dcrry AONBs (Fig. 1). Information associated with statutory designation in the past, local knowledge, map archives and short field visits were used to make decisions. The area included all land in the region with a potential for AONB status, including for example: the existing Sperrins AONB and North Derry AONB; upland areas associated with AONB boundaries, including land between them; lowland areas associated with these uplands, in particular near Coleraine and

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Alan Cooper and Ronald Murray 321

i 60 70 80

300m Contour Lme

. . . . . . . . Exvstang AONB Boundary

I I I

Londonderry

Draperstown

Plumbrldge+.

Figure 1. The North Derry and Sperrins region, showing the boundary of the wider study area following kilometre squares of the Irish Ordnance Survey

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322 A structured method of landscape assessment and countryside management

Limavady; land along the major rivers Foyle, Derg and Strule in the west and the farmed hill and valley systems in the north; rolling, hilly terrain comprising a mosaic of agricultural grassland, bog and heath vegetation in the south, to the north of Cookstown and Omagh.

Land classification

Kilometre squares of the Irish Grid within the study area were allocated to one of 23 land classes derived from a multivariate classification of sample squares in NI (Cooper 1086). Certain land classes were recorded in small numbers and mosaic distribution patterns were frequent. For reasons of simplification, therefore, similar land classes were combined to give a total of ten (A-J) land class groups (Fig. 2). Land classes were combined subjectively but using the criterion that the main hierarchical divisions in the land classification be retained.

Description of land class groups

Group A. This is a low-elevation, flat land class group below 50m. The coast. estuaries and river valley bottoms are typical. The road transport network is dense in comparison to the other land class groups. Mezozoic rocks underlie most of the squares and alluvial gley soils predominate.

Group B. This is a relatively flat, low-elevation land class group with a 51-150m elevation component. The topography is more broken than in group A and the land is at a somewhat higher elevation. There are frequent small villages and a dense but mainly minor road system. Rock types are mainly schists and quartzites with overlying brown podzolic soils.

Group C. This is another relatively low-elevation group centred on North Derry and lying mostly below the 150m contour. It occurs on the lower slopes and bottoms of escarpments, on sloping river and lake sides and at the coast. There is a high frequency of buildings and small streams are ubiquitous. Basalt and Mesozoic rocks predominate, while soils are mainly alluvial and gleyed, with some acid brown earths and grey-brown podzolics.

Goups D. This consists of sloping land at intermediate elevations (51-150m), occurring at the lowland-upland transition. It is at a higher elevation than group C. Rivers and flat valley bottoms are frequent and farm buildings are common. Schists predominate and are associated with brown podzolic soils.

Group E. This is located at higher elevations, largely between the 151 m and 250 m contours, but it often has a considerable proportion of land below 150 m. The main locations are quite steep bottom and middle slopes of mountains generally. There is a high density of buildings for an upland group. Rocks are mainly schists and soils arc characteristically brown podzolics or peaty podzols.

Group F. This comprises flatter, rolling hill land, largely at an elevation of 151-250m. Streams, small loughs and rough grazing Ordnance Survey mapping symbols are frequent. Buildings are less frequent and the road system is less dense than in group E. Rock types are more varied, with basic igneous rocks, schists and basalts frequent. Brown podzolic soils are most frequent in this group, with peaty soils also occurring.

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Alan Cooper and Ronald Murray 323

I I 1 1 1 1 I I I I I

40 50 60 70 80

- 40 Porlrush 0 -

El Land Class A NORTH DERRY

p& Land Class B AONB

m Land Class C

Land Class D

Land Class E

Land Class F

Land Class G Limavady l

- 20 Land Class H

Land Class I

Land Class J SPERRINS

AONB

-10

Dunnamanagh

.Omagh

0 I

10 km 1

Figure 2. The distribution of land class groups in the North Derry AONB and the Sperrins AONB

Group G. This is an upland group centred on the 1.51-250 m contours but including a large proportion of land above and below these elevations. It consists of mainly the steeper, high-elevation land of glen sides and escarpments in the mountains. Schists predominate but there are basalts and other rocks in North Derry associated with Mesozoic strata. Peaty gleys and brown podzolics are the most frequent soils.

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324 A structured method of landscape assessment and countryside management

Group H. This is mountain terrain and uplands, largely between the 1.51 m and 5OOm contours but often with a flatter topography than group G. It is found associated with glen and valley heads where land is less steep. Slopes can be greater when associated with the source of watercourses. The group is dispersed throughout the mountains and hills of the whole region. Schists are the most frequent rocks in the Sperrins with basalt in North Derry. Peaty gleys and brown podzolics are the most frequent soils.

Group I. This occupies terrain mainly between 251 m and 500 m elevation. It is found throughout the Sperrins and is also characteristic of North Derry, where the topography is less steeply sloping. In the Sperrins, schists predominate and in North Derry, basalt. Peaty gleys and blanket peat are the most frequent soils.

Group J. This represents the highest mountain terrain, mainly in the Sperrins, frequently rising to more than 500m. Schists predominate, covered usually with peaty gleys or blanket peats.

Derivution of laruiscape units

Local patterns of land class distribution and land class clusters were used to divide the region into 16 geographically distinct landscape units (Fig. 3). The first step in this process was to delimit high-elevation and upland transitional areas from the lowlands. Mountain areas were delimited as land class groups I and J. Uplands transitional to mountain blocks were delimited as groups E, F, G and H. Landscape units 1,2,4,5,9, and 10 represent lowland areas. Mountain and upland transitional areas are represented by landscape units 3, 6-8 and 11-16.

Unit boundaries within these two major groups were then drawn in relation to selected, distinct physiographic and landform features such as watershed boundaries, and specified juxtapositions of land classes. This process is described in detail by Cooper et al. (1988).

Preliminary landscupe evaluation

Reconnaissance survey was carried out as the next stage, to provide a provisional indication of landscape quality and to select criteria for assessing landscape quality. The range of landscape criteria was limited to those that could be defined or qualified in physical terms. They were selected to represent a broad range of landscape characteristics (Cooper et al. 1988). Elements related to the aesthetic appreciation of landscape were more difficult to define and standardize and for these reasons were not recorded.

Each landscape unit was subsequently surveyed, to describe the distribution of landscape attributes which were considered to either contribute to landscape quality (positive criteria) or detract from it (negative criteria). Information was recorded on field data sheets in qualitative or semi-quantitative form as a subjectively assessed frequency or cover value derived for the unit as a whole using vantage points (see Cooper et al. 1988).

Evaluation of each of the landscape units began by comparing the totals of positive and negative landscape criteria, each scoring respectively + 1 and -I (Tables 1 and 2). Landscape units 7, 8 and 11-15 each had positive total scores. They were considered to be of high landscape quality and worthy of further field study. Unit 12 had the lowest positive total score. Whilst it contained areas of intensive agriculture it had a considerable mountain and woodland interest. Units

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Alan Cooper and Ronald Murray 325

Figure 3. Location of provisional landscape units derived from the Northern Ireland land classification (the AONB boundary is shown as a dotted line)

2,4-6,lO and 16 each had a negative or zero total score, except for unit 6, and were ail considered to be of low value, mainly because of the large proportion of improved agricultural land. While unit 6 had a positive total score, there was so much agricultural reclamation recorded that this was considered to outweigh the positive features.

A simple decision was not possible for units 1, 3 and 9, since they contained localities with outstanding qualities and others which were poor. For example, although unit 1 had a high positive score it also had a relatively high negative score,

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326 A structured method of landscape assessment and countryside management

Table 1. Positive criteria used in preliminary landscape evaluation

Areas

Positive criteria 1 2 3 4 5 6 7 X 9 10

High mountain Mountain + *

Hill terrain * a

coa\t * :k

E\tuar) *

Glen/valley * * * * * *

Heath/bog * :i: * *

Species-rich

vegetation * ‘. “_

Distinct landform * * * *: * :k

Woodland interest * * * *

Field boundary

Interest *

Nature reserve *: *

Recreation

facilit) :k

Antiquit) * * *

Traditional

fwn~ing/field

pattern * + *

Vernacular

building * :i ‘i:

Geomorphological

interest * .k

Integral to

scenic area *

Pmitive score 823255 6 x 6 3

11 12 13 14 15 I6

:,. -1:

1. 4:

i: .* i: * * * :I:

i: * * .% 4:

* *

* *

5 5

*

6 7 6 6

which detracted from its value. The negative criteria were features such as large field size and intensive lowland agriculture. Unit 9 also had major negative criteria, such as intensive lowland agriculture and a well developed road network. These units were assessed as borderline for potential AONB status.

The boundaries of the landscape units considered to be of high landscape quality (7, 8 and 11-15) corresponded well with the existing Sperrins AONB boundary (see Fig. 3). Over 70 per cent of the boundary squares of these units lay within 2 km of the existing designated AONB boundary.

Refined landscape evaluation

Four main criticisms of the evaluation were received from the sponsors of the research (CWB, DoENI):

1. the separation of upland and lowland zones in the land classification broke the continuity of some glens and cut across attractive lowland-upland agricultural transition zones;

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Alan Cooper and Ronald Murray

Table 2. Negative criteria used in preliminary landscape evaluation

327

Areas

Negative criteria 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

* *

Lowland * *

Urban area *

Intensive agriculture * *

Poor fen vegetation

Indistinct landform *

Derelict field boundaries/ post wire fencing

Derelict buildings

Species-poor vegetation *

Poorly landscaped conifer plantation

Reclamation, drainage, peat cutting

Large field size * * Erosion Road network *

Industrial site

* * * *

* * *

* * *

*

*

*

*

* *

* * * *

* * *

Negative score 4 8 4 I 6 2 4

* * *

* *

*

*

*

* *

* *

* * *

4 3 8

*

* *

* * * * *

*

*

* j: *

* * *

2 4 3 I 0 6

lowland areas which are of major importance for cultural heritage, broadleaf woodlands and river valley or coastal features tended also to receive a rather lower evaluation score; areas of more intensively farmed land had been included around units with transitional hill land; there was no consideration of administrative boundaries.

Refinement of the landscape unit boundaries was subsequently carried out to incorporate these criticisms. This was a less formal procedure than the initial assessment. It did not involve a scoring system and placed more emphasis on professional judgement and practical considerations to make decisions. A total of ten landscape units emerged from the refinement process (Fig. 4).

Resource survey and analysis

Sample stratification

Field survey of landscape resources was carried out within a two-way stratified random sampling programme based on land classes and landscape units.

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328 A structured method of landscape assessment and countryside management

Portrush 0

t Limavady .

t

20

n Londonderry

Claudy 0

Dunnamanagh

Draperstown

llion

Cookstown 0

,Omsgh

10 km I

Figure 4. Location of the refined landscape units used to stratify the study area for field survey

Stratification by landscape unit imposed a more regular distribution pattern on the sample squares and allowed subsequent application for management purposes at a local level. A random sample of 116 l-km squares was selected for field survey. Within each landscape unit, sample squares were allocated randomly in proportion to their land class frequency. Sample squares falling next to existing sample squares were t-e-allocated to further minimize sample clumping.

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Alan Cooper and Ronald Murray 329

Physical characteristics of the sampling strata

Using the sampling programme described above, the physical attributes of kilometre squares were recorded from Ordnance Survey maps (1:50 000), Geological Survey maps (1: 625 000) and generalized Soil Survey maps at a scale of 1: 575 000. These data were used to summarize the characteristic composition of the land classes and the landscape units; an example is shown in Table 3. Comprehensive description and analysis is given by Cooper et al. (1988).

Field recording procedure

A random 25-ha quarter-square from each of the kilometre squares within the sampling programme was selected for field survey study. A square size of 25-ha was more suited than a kilometre square to the small scale of landscape variation encountered.

The following information was recorded (Cooper et al. 1988):

1.

2.

3. 4.

woodland: type, position in the landscape, structure, ground flora, soils, management, main species of the understorey, canopy and regenerating species; seminaturaz vegetation: grassland, heath, bog, coastal vegetation and tall herb vegetation; their structure, management and main species present; field boundaries: type, structure, the main species of shrubs and trees; agriculture: grassland, crops; their management, structure and the types and numbers of farm animals;

Table 3. Mean values of map attributes recorded in a random sample of kilometre squares from each land class group in the Sperrins AONB

Land class group

A-D E F G H I J

Land tS50 m (ha) 34 _ - _ _ - _ Land 51-1.50 m (ha) 65 38 12 I4 8 _ _

Land 151-250 m (ha) 1 55 83 63 14 5 5 Land 251-500 m (ha) _ I 5 21 16 95 86 Land 501-1000 m (ha) - _ - _ _ - 9 Mean elevation (m) 89 124 204 231 219 292 388 Highest point (m) 112 217 239 283 210 339 466 Lowest point (m) 66 131 168 180 168 245 304 Distance between

highest and lowest point (m) 568 803 716 895 873 700 895 Gradient of slope (“) 4 6 5 6 I 11 10 Height of hill behind

slope (m) 175 309 300 353 360 364 460 Distance to hill

behind slope (m) 1105 1019 838 691 985 350 188 Distance to valley

bottom (m) 135 99 91 315 353 487 549 Number of road forks 1 I _ _ _ _ _ Number of buildings 9 8 5 3 2 - _

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330 A structured method of landscape assessment and countryside management

5. landscape: artefacts of the built environment, dereliction and recreation together with surface topographical features.

The five resource types were recorded on separate data sheets, each of which held a checklist of coded attributes, a 1:70060-scale map and a data matrix. The data recording procedure consisted of inserting numeric codes onto the maps and then checklist codes into the data matrix for each parcel of land or linear feature.

Information was recorded with reference to a set of habitat and attribute standard descriptors and species codes. Target notes were added for specific parcels of land or linear features and the square as a whole. Fieldwork was completed within three months by one experienced ecologist.

Computer database structure and analysis

Quantitative measurements of land use, linear features and landscape attributes were made from the maps after field survey had been completed, using a digitizing table linked to an IBM-PS2 microcomputer. Column headings on the field data sheet matrix corresponded to the field structure of the computer database. Database analysis was carried out with dBASE III PLUS (Ashton-Tate 1985), run on an IBM-PS2 microcomputer. Information from the database could be retrieved for any combination of resource type or management characteristic and could be presented for the study area as a whole or for specified land units or localities.

Tables 4 and 5 illustrate the way the results were used to summarize the distribution of woodland and seminatural vegetation types in the main land class groups. Applications included estimating the total area of particular resource types and inferring land use change for resource management purposes. For example, land class group G-H has a percentage mean area of 3.2 per cent covered by coniferous forest plantation (Table 4) but a 12 per cent cover of poor fen (Table 5), a vegetation type with little agricultural or nature conservation value in the AONB, but with considerable potential for tree growth. If the socioeconomic factors currently constraining land use for afforestation were to change, land units containing a high proportion of land class group G-H would be subject to particular landscape change. Landscape unit 10 in the north of the AONB would be affected most.

Table 4. Percentage mean area of woodland in land class groups of the Sperrins AONB

Land class group

A-D G-H I-J AONB Total

(km’)”

Seminatural broadleaf woodland

Seminatural scrub Coniferous plantation Broadleaf and mixed

conifer plantation

4.6 I.4 14 I.2 l3.S 2.3 I.2 0.9 <o. I 0.9 Y-I

<a I 4.0 3.2 7.7 1.6 SO.4

0.2 0.X 0.3 0.3 3.7

” Estimate

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Alan Cooper and Ronald Murray 331

Table 5. Percentage mean area of seminatural vegetation in land class groups of the Sperrins AONB

Land class group

A-D E-F G-H I-J AONB Total

(km’)”

Species-rich grassland Reedbeds, fen and swamp Bent/fescue hill pasture Mat-grass hill pasture Bracken Gorse heath Wet heath Dry bog Poor fen Wet bog

I.3 1.6 1.4 1.0 10.1 <o. 1 0.2 <o. 1 _ 0.1 0.8

- 0.9 2.4 0.3 0.9 10.2 - 0.1 0.1 12.8 4.3 41.5 0.5 0.3 0.8 _ 0.3 3.1 0.6 1.4 0.2 _ 0.6 6.2 1.9 12.2 26.9 31.1 22.8 249.3 1.2 5.1 14.1 22.3 12.6. 138.0 1.9 6.9 12.0 9.0 8.1 89. I 8.8 6.6 I.5 9.6 8.1 88.3

” Estimate

Table 6 (in which the units have been grouped to simplify presentation) shows how the data were used to compare peatland exploitation regimes in the landscape units. Peatland resources in each unit are exploited in different ways: units 3,4 and 5, for example, are subject to particularly intensive use.

Analysis of the database can also be carried out in a less formal manner, as in the prescription of resource management guidelines for land units or land classes, for example. The guidelines are based on resource descriptions and an evaluation of their local significance to wildlife and the landscape. They can be specific for each resource but should not be detailed working prescriptions since these are best prepared to suit specific site circumstances. An example of the type of management guidelines prescribed is given in Table 7.

Table 6. Management and structure of peatland resources in landscape units of the Sperrins AONB”

Landscape Unit

2 3-5 6-8 9 10

Hand cutting 9 31 13 2 14 Machine cutting 1 6 2 _ 6 Agricultural drainage 26 20 14 1 21 Burning 6 15 3 I 8 Disturbance 2 22 5 8 Erosion 15 20 5 _ 11

u As percentage mean area of each unit

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Table 7. Peatland vegetation management guidelines for the Sperrins AONB

Heath, bog and poor fen I.

2.

3. 4.

5.

Retain all intact upland and lowland peat bog. particularly in land units 3. 5. 6. 7 and IO.

Manage abandoned lowland cutover peat bog for wildlife. for example in the more intc\ively

farmed land unit 9.

Plan for the ecological rehabilitation of peat bog currently being cut by machine.

Implement stock density control and access to upland peatlands (mainly in land units 2 and 6)

to minimize erosion and to encourage heather cover.

Rationalize and reduce the frequency of burning on pentland vegetation.

Validation of resource estimates

Coniferous forest. Validation of the estimates of woodland plantation predicted from the field sampling programme has been carried out against independent full cover survey data sets. Information on the extent of coniferous plantation and broadleaf woodland in the Sperrins AONB was obtained from the Forest Service (DANI) annual reports. The predicted and actual percentage mean areas of plantation in the study area were close and there was a good correlation between the amounts present in the land class groups (Table 8) and the landscape units (Table 9). This is despite the fact that coniferous forest is mostly restricted to a small number of large plantations and that the total area of plantation is quite small.

Peatlands. Validation of the estimates of peatland was carried out against the Northern Ireland Peatland Survey (Cruickshank and Tomlinson 1988). The total amount of peatland estimated in the Sperrins, using bog and heath categories from the AONB survey, was 47523 ha compared to 46800 ha from the NI Peatland Survey. For the North Derry area the figures are 1400 ha and 1390 ha, respectively. Estimates from both surveys are within 1.5 per cent of each other in both areas, despite differences in recording procedures between the two surveys. Comparison of other related peatland attibutes between the two surveys is given in Table 10.

Table 8. Comparison of estimated and actual percentage mean area of coniferous plantation in combined land class groups of the Sperrins AONB

Land class group

A-D EC-F G-H I-J AONB

Predicted -CO.1 3.0 3.2 7.7 46

Actual 0.7 4.6 4.3 0.5 5.8

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Alan Cooper and Ronald Murray 333

Table 9. Comparison of estimated and actual percentage mean area of coniferous plantation in the landscape units of the Sperrins and North Derry AONBs

Landscape unit

1AC

N. Derry Sperrins

1B AONB 2 345 678 9 10 AONB

Predicted <O. 1 19.4 10.5 I I.9 8.3 3.3 <O.l 1.2 4-6 Actual 0.6 24.6 12.6 13.1 x.1 5.4 0.3 2.0 5.x

Statistical summary of resource estimates

There was a wide variation in the frequency, amount and distribution patterns of resources. Cases of undersampling and oversampling of particular resource types are inevitable, therefore, unless different sampling strategies are used for each type. Separate sampling strategies matched to different resources have not been used so far in this work, mainly because they are costly and inappropriate, given the generalized nature of the information system being established.

A sampling intensity of about 2.5 per cent by area, however, has been shown by validation tests (Cooper et al. 1988) to give a reasonable estimate of the more common, widely spread resources. Sampling intensity in the Sperrins was rather less, at 2.2 per cent. Also relevant is the assertion that conventional significance tests are inappropriate since in many cases the data do not usually conform to conditions of normality. Data sets are generally positively skewed, a feature accentuated by frequent zero values.

Analysis of variance between land class groups in the Sperrins is presented in Table 11, which only tabulates selected resource types. Significant differences between means are linked to variation in physical differences between the land class groups. The reasons for non-significant differences are also usually apparent; for example, the ubiquitous distribution of wet bog in the Sperrins, the small area and low frequency of species-rich wet grassland and the distribution of coniferous forests as a small number of large plantations.

Table 10. Percentage area of selected peatland categories in the North Derry AONB and Sperrins AONB, derived from the present study and the Northern Ireland peatland survey“

North Derry AONB

NI AONB peatland survey survey

Sperrins AONB

NI AONB peatland survey survey

Peat cutting by hand 35 34 31 4x Drained peat 0 12 33 11 Eroded peat 4 12 20 19

u Cruickshank and Tomlinson (1988)

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334 A structured method of landscape assessment and countryside management

Table 11. Percentage and mean area (km’) of seminatural vegetation and land use (A) and mean length (km) per square kilometre of field boundary types (L) in land class groups of

the Sperrins AONB

Land class group

A-D E-F Significance (P)

Seminatural broadleal

WOCKhld

Coniferous plantation

Species-rich wet

grassland

Wet heath

Wet bog

Perennial ryegrass

Arable/fallow

Hedgcbank with

scattered or

overgrown shrubs

Post/wire and other

fence5

Earth or stone bank

A 4.6 I.4

A -a I 4.0

A I a 1.1

A 0. I 4.x

A 8.X 6.6

A 44.0 ‘7.0

A 7,s 2.6

I. 3.4 2.0

L 3.1 4.2

L 7.3 94

0.7 <o. I

34 I.8 9.8 0-l

I1.S.”

woo I n.s.

OU) I

0.00 I

Discussion

Land classification

The land classification puts physical variation within the study area into a broader, regional context (Cooper 1986), providing a framework within which policy decisions on resource management can be made. It is a consistent, repeatable method of dividing the study area on the basis of its physical and related settlement characteristics. It has sufficient resolution to bring out local patterns of variation and its hierarchical structure means that the land classes can be combined to any given level of generalization. The problems associated with a grid square approach to assessing landscapes are that boundaries between contrasting land types can be blurred and arbitrary divisions of continuous landscape features can be created. In the context of the objective of the study, however, which was to provide a framework for a generalized information system and landscape evaluation, the grid square classification is a pragmatic approach to handling a multivariate system. Other methods of grid square classification, such as that presented by Briggs and France (1983), have been used for landscape assessment but there are no clear practical or economic advantages over the technique of Bunce ef al. (1983).

Following land classification, further stratification on the basis of repeating patterns of land classes and other geographical attributes reduces internal heterogeneity within the study area by delimiting the main areas of variation. This is useful in a planning context for highlighting local differences and developing management guidelines. In addition, dual stratification by land class and geographical unit is explicit but gives flexibility at both the analysis and display stages.

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Alan Cooper and Ronald Murray 335

Landscape evaluation

The first stage in assessing landscape status is the selection of a wider study area within which more detailed work can be carried out. This is a desk study, requiring the collation of available information. The criteria for selecting the wider study area are limited to a small number of broad landscape elements related, for example, to the presence of uplands, lakelands, deciduous woodland and less intensive hill farming. There is also potential for using the regional distribution of land classes for the process of defining the wider study area.

The second stage is to classify kilometre squares of the wider study area by multivariate land classification, land classes being combined into composite groups to simplify variation if necessary. The characteristics of the wider study area are summarized in terms of land class distribution patterns and their frequency, to provide a physical description. Areas (that is, land units) with similar land class characteristics are then defined using land form and land class criteria such as the same land class, specified groups of land classes, specified proportions of different land classes, and specified land class juxtapositions. This is followed by a field assessment of the defined land units and subsequent amendment of their boundaries.

The final stage of the assessment involves carrying out a more detailed field study of landscape elements for the land units delimited by stage two, with the aim of excluding areas which are unsuitable for AONB status. Appraisal criteria are selected on the basis of reconnaisance field survey and consist of simple quantitative or qualitative elements that either contribute or detract from landscape quality. Some criteria can be given a greater weighting than others. A scale of land suitability for AONB status using weighted positive and negative criteria can be described but this is not essential, particularly in the early stages of work. Not all criteria need be used in the appraisal. What is crucial is that the criteria are described fully, along with the rationale for their selection, so that the reasoning can be followed by others. Similarly, the incorporation of aesthetic landscape criteria is possible at any stage in the assessment.

Land units can be assessed as a whole or alternatively the assessment can be carried out by applying the criteria to a sample of kilometre squares in each land class. This involves selecting and surveying a random sample from each unit, stratified by land class. The frequency or some other quantitative measure of each landscape element can be used in the assessment if required, taking account of the land class composition of each unit. This approach, sampling grid squares in land classes for landscape quality, followed by an evaluation of land classes, has been carried out by Bunce and Smith (1978). The degree of quantification used for the assessment process is related to the objectives of the study and the resources available. A simple qualitative or semi-quantitative approach with no land class sampling was found to be adequate and optimally efficient for the present work.

An efficient full-cover landscape evaluation procedure has recently been developed by the Countryside Commission (1987). However, although it is explicit, it cannot easily be linked to other information systems since it is dependent on observations made from viewpoint stations. An integral step in the landscape assessment process described in the present research is that evaluation is carried out independently of land classification. This allows re-evaluation if it becomes necessary, for example to meet changing circumstances and objectives. Coppock (1980) has pointed out that no one system of evaluation is universal, since the needs of, and values within, the planning process often change.

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336 A structured method of landscape assessment and countryside management

A feature of the evaluation process is that a first approximation of landscape quality can be carried out which can then be refined at a later stage. The unavoidable subjectivity associated with the evaluation is made explicit by linking the evaluations to a quantitative description of simple physical attributes using land classification. The underlying assumption is that landscape quality is related to, and can be broadly defined by, physical attributes (Robinson et al. 1976). This assumption is particularly valid when physical attributes are also related indirectly to, for example, settlement patterns.

As a first approximation. the evaluation replicated quite successfully the boundaries of the existing Sperrins and North Derry AONBs, which had been drawn by professional geographers and planners. This was despite considerable changes in landscape quality, involving widespread afforestation and agricultural intensification since 1968, which would otherwise have led to a better coincidence between the two evaluations. The degree of coincidence, however, is largely irrelevant. The main point is that the evaluation derived from reconnaisance survey of the geographical units provided a rational basis for discussing value decisions and other evaluation criteria during the refinement process carried out by the Countryside and Wildlife Branch (DoENI).

Landscape resource survey

Resource survey and analysis based on sample grid squares gives quantitative information that can be analysed by land class and geographical unit or for the AONB as a whole. This information is a basic requirement for regional planning. It is necessary for understanding policy implications, recognizing environmental problems and monitoring change. It is particularly relevant to the current debate on rural land use issues since there is a dearth of information on aspects of the environment relating to the landscape and its ecological components. If, for example, farmers are given an environmental management role, data will be needed on landscape and ecological diversity within and between regions.

Stratified random sampling by multivariate land class is an efficient way to carry out resource survey. If landscape evaluation is considered as only part of the landscape assessment procedure, with land classification, resource survey and analysis as an integral part of the process, the evaluation is also cost effective. Land classification, evaluation, field survey, resource analysis and formal reports were completed within 1.5 man years. Cost effectiveness is not usually good when landscape evaluation is initiated as a free-standing exercise except when carried out on a reconnaisance basis (Country Commission 1987).

The land class database provides a useful, practical summary of the current distribution and management of resources. Information can be fed directly into the strategic planning and consultation processes as demonstrated by Bunce and Smith (1978) and Highland Regional Council (1985). Interaction with planners and land managers in the Countryside and Wildlife Branch who are using the data to develop AONB management strategies was essential to the success of the work.

Access to information in the database, by users from different backgrounds and with different interests, is facilitated by the application of standard, easily available and readily applied computer software packages supported by microcomputer. The resulting information system is flexible, yet it is sufficiently powerful to meet the routine needs of CWB: for example, queries on the extent and distribution of resources such as heather moorland or the rate of mechanized peat extraction.

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Alan Cooper and Ronald Murray 337

Structured methods of landscape assessment, linking description, classification, analysis and evaluation, provide an integrated framework within which land use management and advice decisions can be debated. There are clear advantages over piecemeal approaches to rural land use issues, with the structured approach capitalizing on the efficiency of the various procedures used at different stages. In addition, issues of landscape quality and environmental management and problems are linked in a way that is useful for strategic planning.

Acknowledgements

The work was funded by the Countryside and Wildlife Branch of the Department of the Environment for Northern Ireland. Our thanks go the Nigel McDowell and Kilian McDaid for their professional help and advice relating to presentation. We also thank Andrew Stott for his enthusiastic support for the project and much useful constructive criticism.

References

Ashton-Tate (1985) dBase III Plus. Torrance: Ashton-Tate. Bunce, R. G. H. and Smith, R. S. (1978) An ecological survey of Cumbria. Kendal: Cumbria

County Council and Lake District Special Planning Board. Bunce, R. G. H., Barr, C. J. and Whittaker, H. (1983) A stratification system for ecological

sampling. In Ecological mapping from ground, air and space (R. M. Fuller, ed. ), pp. 39-46. Cambridge: Institute of Terrestrial Ecology, Symposium No. 10.

Briggs, D. J. and France, J. (1983) Classifying landscapes and habitats for regional environmental planning. Journal of Environmental Management, 17, 249-261.

Cooper, A. (1986) A system of land classification for the Mourne AONB. Jordanstown: University of Ulster, Department of Environmental Studies, Report to the Countryside and Wildlife Branch (Department of the Environment for Northern Ireland).

Cooper, A. and Murray, R. (1987a) A landscape ecological study of the Mourne AONB. Jordanstown: University of Ulster, Department of Environmental Studies, Report to the Countryside and Wildlife Branch (Department of the Environment for Northern Ireland).

Cooper, A. and Murray, R. (1987b) A landscape ecological study of the Antrim Coast and Glens and Causeway Coast Areas of Outstanding Natural Beauty. Jordanstown: University of Ulster, Department of Environmental Studies, Report to the Countryside and Wildlife Branch (Department of Environment Northern Ireland).

Cooper, A., Murray, R., McCann, T. and Forsythe, J. (1988) A lana!scape ecological study of the Sperrins and North Derry Areas of Outstanding Natural Beauty. Coleraine: University of Ulster, Department of Environmental Studies, Report to the Countryside and Wildlife Branch (Department of Environment Northern Ireland).

Coppock, J. T. (1980) The concept of land quality: an overview. In Land assessment in Scotland (M. F. Thomas and J. T. Coppock. eds), pp. l-11. Aberdeen: Aberdeen University Press.

Countryside Commission (1987) Landscape assessment: a Countryside Commission approach. Cheltenham: Countryside Commission, CCD 18.

Countryside Commission (1988) A review of recent practice and research in landscape assessment. Cheltenham: Countryside Commission, CCD 25.

Cruickshank, M. M. and Tomlinson, R. W. (1988) Northern Ireland peatland survey. Belfast: Queen’s University, Report to Conservation Service, Department of the Environment for Northern Ireland.

Department of the Environment for Northern Ireland (1988) Antrim Coast and Glens Area of Outstanding Natural Beauty: guide to designation. Belfast: HMSO.

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338 A structured method of landscape assessment and countryside management

Department of the Environment for Northern Ireland (1989) Mourne Area of Outstanding Natural Beauty: policies and proposals. Belfast: HMSO.

Highland Regional Council (1985) HRCIITE land classification system. Inverness: Highland Regional Council, Planning Department, Information Paper No. 5.

Robinson, D. G., Laurie, I. C., Wager, J. F. andTrail], A. L. (1976) Landscape evaluation: the landscape evaluation research project 197061978. Manchester: University of Manchester, Centre for Urban and Regional Research.

(Revised manuscript received 27 May 1992)


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