Analysing the vegetation information content of airborne remotely sensed data to improve understanding of archaeological features
Start date: 1 September 2010
Aerial imaging for identifying archaeological sites has been practised for more than a century in Britain. Nonetheless, the use of airborne digital remote sensing has enjoyed a recent resurgence with the increasing availability of lidar and digital spectral data to historic environment professionals. Familiarity with remotely sensed datasets and processing techniques has progressed our ability to identify possible sites of archaeological interest within lidar and multispectral data, but little work has been done to understand how these data might be applied to non-alluvial landscapes.
Through a detailed study of archive CASI, lidar and vertical 4-band aerial photography data, for an area on Salisbury Plain, Wiltshire, it has been possible to examine the vegetation and topographic elements of the landscape that represent archaeological features. This study illustrated the importance of the red edge region of the spectrum in identifying subtle vegetation changes in this chalk grassland environment. Spectral data from January and May of 2001 were examined, revealing seasonal differences in monument visibility. Additionally, by digitally combining the spectral and topographic data the value of the sum of complementary data sets was firmly established as greater than that of each individual source.