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The combined effects of erosive rains, steep slopes and human land use have caused severe land degradation in the Ethiopian Highlands for several thousand years, but since the 1970s, however, land rehabilitation programmes have been established to try to reverse deterioration. In order to characterize and quantify the transformations in the north Ethiopian Highlands, a study was carried out over 8884 km² of the Tigray Highlands of northern Ethiopia. Using Landsat Multispectral Scanner and later Thematic Mapper imagery (1972, 1984/1986 and 2000), historical terrestrial photographs (1974–1975) and fieldwork (2008), we prepared land use and cover maps. For assessing the use of the historical terrestrial photographs, Landsat images from 1972 were classified using two different methods, namely conventional change detection (image differencing) and ground truthing (using the historical photographs of 1974–1975). Results show that the use of terrestrial photographs is promising, as the classification accuracy based on this method (Kappa coefficient 0·54) is better than the classification accuracy of the method based on image differencing (Kappa coefficient 0·46). Major land use and cover changes indicate the following: (1) a gradual but significant decline in bare ground (32 per cent in 1972 to 8 per cent in 2000); (2) a significant increase of bushland (25 to 43 per cent) and total forest area (including eucalypt plantations, 2·6 to 6·3 per cent); and (3) creation of numerous lakes and ponds. The dominant change trajectory (27 per cent of the study area) indicates a gradual or recent vegetation increase. These changes can be linked to the population growth and the introduction of land rehabilitation initiatives, complemented by growing awareness of land holders. Copyright © 2012 John Wiley & Sons, Ltd.
