Information and Advisory Note Number 120(updated version of No.75)                                          Back to menu

Land cover change in Scotland: National Countryside Monitoring Scheme results for the 1970s and the 1980s

1. Introduction

1.1 National Countryside Monitoring Scheme (NCMS) results now describe Scotland's land cover for the 1970s and the 1980s. These are extrapolated from a stratified random sample which covers 7.5% of the land area of Scotland. Land cover information relating to 31 area and 5 linear features was derived from aerial photographs and mapped at 1:10,000 scale. The maps were digitised and entered into a Geographic Information System (GIS) in which the data were processed and classified. Statistical programmes calculated estimates of areas and lengths, together with change within and interchange between feature types. Accompanying all results are confidence intervals which indicate the precision of estimates. The project was designed to identify changes of 10% or more in spatial or linear extent with 95% confidence.

1.2 Summary results for Scotland are shown in Table 1.

2. Estimates of net change

2.1 Grassland was the largest land cover group, covering approximately 28% of the country. About half was rough grassland. There was little, if any, change in the area of rough or intermediate grassland. Smooth grassland was reduced by 15%, mostly to arable.

2.2 Mire was the second most extensive group. This was interpreted into upland categories of heather and grass dominated blanket mire and the less common lowland mire. All were reduced in area; heather dominated mire by 21%, grass dominated mire by 9% and lowland mire by 24%. As a group mire was reduced by 16% of its 1970s area.

2.3 Heather moorland covered 15% of Scotland in the 1970s and remained little changed.

2.4 The arable area increased by 15%, mostly from smooth grassland.

2.5 In the woodland group, semi-natural broadleaved woodland was reduced by 10%. 32% of mixed woodland was lost, mostly to other woodland categories. Coniferous and young plantation increased by 58% and 54% respectively.

2.6 In the water group there was a 30% increase in wet ground.

2.7 Built land increased by 8% and transport corridors (roads and railways) by 9%. There were also increases of 214% in bare ground and 20% in recreational land.

2.8 Bracken increased by 63%.

2.9 Linear features show a 23% reduction in the length of hedgerows but a 10% increase in the length of lines of trees. The length of ditches increased by 60%.

TABLE 1: FEATURE ESTIMATES FOR SCOTLAND (1970s-1980s)

TOTAL AREA: 77837 km²




2.10 Table 2 summarises gains and losses.

3. Interchange

3.1 Figure 1 (page 5) illustrates the major interchanges (> 0.5% of Scotland's area) between land cover features for the 1970s-1980s.

3.2 In the lower left part of the diagram, arable - grass rotation, as part of the agricultural cycle, results in a large interchange and a net gain from grassland to arable.

3.3 Within the grassland group interchanges occurred among the three types, with a general trend towards grassland improvement.

3.4 Large interchanges between heather moorland and rough grassland took place, with a net loss of heather moorland. Causes may be associated with changes in land management, notably muirbum (the burning of heather to provide fresh grazing for deer and grouse) and shifts in the intensity of hill grazing.

3.5 Conversion of blanket mire to rough grassland and heather moorland occurs when bog is drained and prepared for commercial forestry. The drainage of mire, as well as the afforestation of mire, heather moorland and rough grassland is shown in the upper part of Figure 1. This also shows that, while heather moorland remained largely unchanged in area from the 1970s to the 1980s, losses did occur from conversion to grassland and planting to forestry. These were compensated for by mire drainage.

3.6 Conversion of rough grassland to bracken occurred.

3.7 The general trend has been a reduction of semi-natural features. Blanket mire, heather moorland and rough grassland were lost to plantation forestry, and there was a shift within the grassland group towards grassland improvement.

4. Regional comparisons

4.1 NCMS results are also produced for each of the 12 former Scottish administrative regions (as portrayed by the Ordnance Survey Local Government Areas map of 1984).

4.2 Areas which retained a high proportion of semi-natural land cover and which experienced relatively little change include the Western Isles and Shetland, and to a lesser extent Highland. These areas were characterised mostly by upland areas of blanket bog, heather moorland and grassland communities.

4.3 Regions with substantial semi-natural cover but higher rates of change include: Borders, Dumfries and Galloway, Grampian, Central, Tayside and Strathclyde. In these areas, semi-natural land cover in the uplands gave way to afforestation. In the lowlands, agricultural intensification took place with grassland improvement and an increase in arable.

4.4 Regions with relatively little semi-natural cover and moderate levels of change are Orkney, Fife and Lothian.

5. Conclusions

5.1 Results for the 1970s-1980s comparison confirm the trend established by the 1940s-1970s results i.e. that semi-natural features decreased. In the 1970s 63% of Scotland could be classed as 'semi-natural'. By the 1980s the semi-natural land had decreased to 58%.



TABLE 2: NET CHANGE FOR SCOTLAND (1970s-1980s)

Ordered by size of change





Figure 1: Interchanges greater than 0.5% of the area of Scotland (1970s-1980s)

6. Further reading

Mackey, E.C., Shewry, M.C. and Tudor, G.J. (1998). Land cover change: Scotland from the 1940s to the 1980s. The Stationery Office, Edinburgh.

Tudor, G.J. and Mackey, E.C. (1995). Upland land cover change in post-war Scotland. In Heaths and Moorland: Cultural Landscapes. (Eds. D.B.A. Thompson, A.J. Hester and M. B. Usher). HMSO, Edinburgh.

Tudor G.J., Shewry M.C., Mackey E.C., Elston D.A. & Underwood F.M. (1999). Land Cover Change in Scotland: The Methodology of the National Countryside Monitoring Scheme. Scottish Natural Heritage Research, Survey and Monitoring Report No 127.

A more colourful view can be obtained from the SNH web site: www.snh.org.uk (under environmental audit).

7. Authors

Dr Gavin Tudor
National Countryside Monitoring Scheme Project Manager, 1986-1997

Mike Shewry
Environmental Statistician
 Environmental Audit Unit
 Chief Scientist's Unit

8. Contact for advice and information

Ed Mackey
Head of Environmental Audit Unit
Chief Scientist's Unit
Scottish Natural Heritage
2 Anderson Place
EDINBURGH
EH6 5NP

Tel 0131-447 4784
 Fax: 0131-446 2405
 

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