The effect of field experience on the accuracy of identifying land cover types in aerial photographs

Abstract

The purpose of this study was to examine the contribution of field experience to the attribute accuracy of land cover maps based on interpretation of aerial photographs. A senior photogrammetrist using true colour aerial photographs delineated land cover polygons in two areas with similar, but not identical, land cover features. Ten experts with long experience from interpretation of aerial photographs were then asked to label these land cover polygons. The experts fell into two broad categories: ‘field trotters’ and ‘photogrammetrists’ according to their professional background. After completing the labelling of the polygons in the first area, all experts spent 1 day in the field in order to compare their results to ground truth. The fieldwork was supervised by a vegetation ecologist. After the field session, the experts proceeded to label the polygons in the second area. The results did not reveal statistically significant differences between the two groups. Neither did any of the groups improve their performance as a result of the fieldwork.