399 
accounted for "by the inclusion of more types of dereliction and more sites 
previously unsurveyed, rather than a real increase in the number of sites 
becoming derelict. 
USE OP DATA 
Although the data which were derived from the survey will be used by 
the planning authorities concerned it is not yet clear exactly how it 
will form part of the planning process, although reclamation will 
obviously be a key factor. 
The data are being used at the University of Aston, however,for a 
landscape quality study. A map prepared by Glamorgan County Planning 
Department and showing the quality of the landscape, is being compared 
for selected areas, with the spoiled landscape data. Although one would 
expect a good correlation between the amount of spoiled landscape and 
the quality of the landscape as a whole, this is less important than 
explaining the anomalies. Por example, a disused railway in a cutting 
will take up a large land area but because of its unobtrusiveness will 
score an average to high grade of landscape quality. Conversely, 
derelict buildings although occupying little land surface will detract 
markedly from the surrounding landscape. 
It is hoped that the emergence of relationships such as these will 
usefully increase our understanding of the effects of the spoiled 
landscape on the visual landscape as a whole. 
CONCLUSIONS 
Although it has not been possible to discuss all aspects of the 
survey in Glamorgan, it is of interest to state the conclusions reached 
regarding the role of the aerial photograph in such work. 
Firstly, the potential of the technique of air—photo interpretation 
has been proven to the extent that it is no longer more than just a 
possibility. This suggests that more work should now be done by other 
planning authorities to refine the technique further. 
Secondly the use of photographs at a scale of 1:5000 has been found 
to be most satisfactory since it provides enough detail for features to 
be identified in both urban and rural environments. The only 
disadvantage of this scale lies in the number of photographs to be 
examined (about 6,000 prints cover the County). 
Lastly, although previous studies used the photograph as a sole source 
of information, it is felt that best use is made of the photographs when 
used in close conjunction with other sources. In this way the survey 
not only produces the most up to date data, but ensures that air-photo 
interpretation is more reliable.