great britain historical gis project: a vision of britain though time generating vector data and...
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Great Britain Historical GIS Project:A Vision of Britain though Time
Generating Vector Data and Statistics from the Stamp survey
Brian Baily and Humphrey Southall(Department of Geography,University of Portsmouth)
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Great Britain Historical GIS Project:A Vision of Britain though Time
Structure of presentation:
• Published and unpublished maps of the Land Utilisation Survey of Great Britain
• How accurate was the LUSGB?• Generating Quantitative Data from the LUSGB:
– Scanning– Geo-rectification– Classification– Vectorisation
• Research funded by:– Environment Agency– DEFRA– Frederick Soddy Trust
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Great Britain Historical GIS Project:A Vision of Britain though Time
LUSGB One Inch sheets
• Published using 9 different printers, so significant variation
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Great Britain Historical GIS Project:A Vision of Britain though Time
LUSGB unpublished maps of upland Scotland
• 56 sheets covering upland Scotland never published due to lack of funds, although survey work fully complete
• Water-colour versions deposited with RGS
• Individually signed-off by Stamp
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Great Britain Historical GIS Project:A Vision of Britain though Time
LUSGB 10 mile to the inch summary sheets
• Use slightly simplified classification
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Great Britain Historical GIS Project:A Vision of Britain though Time
LUSGB Colour separations
• Held by LSE library
• Survive only for 20 sheets, and the southern national summary sheet
• Sample shows light green layer, i.e. pasture
• Very easy to computerise
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Great Britain Historical GIS Project:A Vision of Britain though Time
Digitising the Land Utilisation Survey
• Project in 2004 funded by Environment Agency and DEFRA scanned and geo-referenced all published sheets– Greatly assisted by map
librarians around Britain
• Additional project in 2005 funded by Soddy Trust added unpublished Scottish sheets– Whole LUSGB finally
published!
• All now available on Vision of Britain web site:– www.VisionOfBritain.org.uk
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Great Britain Historical GIS Project:A Vision of Britain though Time
How accurate could the Stamp survey be?
• Carried out by schoolchildren• Instruction leaflet only 4 sides
– Little discussion of defining either the urban fringe or the moorland fringe
• And were the terms well-defined anyway?– "We have never been able to get a satisfactory dividing line
and our definition has not in practice amounted to much more than saying that rough grazings are grazings that are not smooth" (Minute of 28/7/1941, in PRO MAF 38/211)
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Great Britain Historical GIS Project:A Vision of Britain though Time
Comparing the LUSGB and the 1931 Farm Census
Land utilisation Survey
1931 Agricultural Census
Arable Arable land
Permanent grass Permanent Grass. For hay Permanent grass. Not for hay
Orchards
Forests and woodland
Rough grazing Rough Grazings
Houses with gardens
Land agriculturally unproductive
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Great Britain Historical GIS Project:A Vision of Britain though Time
The 1930s in longer-term perspective
England and Wales
Worcestershire
Arable versus Permanent Grass from the Farm Census
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Great Britain Historical GIS Project:A Vision of Britain though Time
Comparison of total acreages:
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Great Britain Historical GIS Project:A Vision of Britain though Time
Comparing Arable Land
Cornwall
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Great Britain Historical GIS Project:A Vision of Britain though Time
Mapping Arable Land
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Great Britain Historical GIS Project:A Vision of Britain though Time
Comparing Permanent Pasture
R2 = 0.9525
0
100000
200000
300000
400000
500000
600000
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900000
0 100000 200000 300000 400000 500000 600000 700000 800000 900000 1000000
Permanent Grass: LUS
Pe
rma
ne
nt
Gra
ss
: A
gri
cu
ltu
ral
Ce
ns
us
Cornwall
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Great Britain Historical GIS Project:A Vision of Britain though Time
Comparing Rough Grazing
R2 = 0.9532
0
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100000
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200000
250000
300000
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0 50000 100000 150000 200000 250000 300000 350000 400000
Rough Grazing: LUS
Ro
ug
h G
rax
ing
: A
gri
cu
ltu
ral C
en
su
s
Cornwall
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Great Britain Historical GIS Project:A Vision of Britain though Time
From the Cornwall County Report• “It is clear that the Land Utilisation surveyors have included as arable
only land under crops or newly laid down to grass; all other grassland has been recorded as permanent grass (including long-ley) whilst some neglected grass returned by farmers as “rough grazing” has also been included as grassland. The Survey’s total of rough grazing is nearly all true unenclosed moor, some of which escapes the agricultural returns.” (p. 465)
• Farms within Cornwall typically “have 25-30% of their acreage under crops, and the remainder under long-ley or permanent grassland. This long-ley grassland, which may be under grass for from four to eight years, is typical of Cornwall as it is of many other counties on the west side of Great Britain” (p. 418)
• It was not true that the surveyors were ill-trained children. Local volunteers only surveyed about a third of the county and “it became apparent that the survey could best by carried out by academically trained geographers” (p.465). Stamp was particularly keen on the correct representation of Cornwall as he was a part-time resident himself (p. 408)