Journal of Geographical Sciences ›› 2018, Vol. 28 ›› Issue (10): 1538-1559.doi: 10.1007/s11442-018-1560-3

• Orginal Article • Previous Articles     Next Articles

Changes in land use/cover mapped over 80 years in the Highlands of Northern Ethiopia

Guyassa ETEFA1,2(), FRANKL Amaury1,3, LANCKRIET Sil1, Demissie BIADGILGN1,4, Zenebe GEBREYOHANNES5, Zenebe AMANUEL2, POESEN Jean6, NYSSEN Jan1   

  1. 1. Department of Geography, Ghent University, Belgium
    2. Department of Land Resources Management and Environmental Protection, Mekelle University, Ethiopia
    3. Research Foundation Flanders (FWO), Brussels, Belgium
    4. Department of Geography and Environmental Studies, Mekelle University, Ethiopia
    5. Institute of Geo-information and Earth Observation Sciences, Mekelle University, Ethiopia
    6. Division of Geography, Department of Earth and Environmental Sciences, KU Leuven, Belgium;
  • Received:2017-04-12 Accepted:2017-09-13 Online:2018-10-25 Published:2018-10-25
  • About author:

    Author: Etefa Guyassa, PhD, specialized in physical geography. E-mail: etefag@gmail.com

Abstract:

Despite many studies on land degradation in the Highlands of Northern Ethiopia, quantitative information regarding long-term changes in land use/cover (LUC) is rare. Hence, this study aims to investigate the LUC changes in the Geba catchment (5142 km2), Northern Ethiopia, over 80 years (1935-2014). Aerial photographs (APs) of the 1930s and Google Earth (GE) images (2014) were used. The point-count technique was utilized by overlaying a grid on APs and GE images. The occurrence of cropland, forest, grassland, shrubland, bare land, built-up areas and water body was counted to compute their fractions. A multivariate adaptive regression spline was applied to identify the explanatory factors of LUC and to create fractional maps of LUC. The results indicate significant changes of most types, except for forest and cropland. In the 1930s, shrubland (48%) was dominant, followed by cropland (39%). The fraction of cropland in 2014 (42%) remained approximately the same as in the 1930s, while shrubland significantly dropped to 37%. Forests shrank further from a meagre 6.3% in the 1930s to 2.3% in 2014. High overall accuracies (93% and 83%) and strong Kappa coefficients (89% and 72%) for point counts and fractional maps respectively indicate the validity of the techniques used for LUC mapping.

Key words: fractional map, Google Earth, land use/cover, multivariate adaptive regression, Italian aerial photographs