| Studying the human dimensions of environmental phenomena emphasizes mapping land-use/land-cover patterns over space and time. Land degradation is a devastating phenomenon that has accelerated from increasing population growth and changing lifestyles. This phenomenon becomes more critical and dangerous when it occurs in a transition zone between arid and semi-arid regions. Northwestern Al-Mafraq City in Jordan is located in this type of zone, the transition Badia zone. It represents a buffer between the arid and the semi-arid zones with annual rainfall ranges between 150-250 mm. This area is facing a drastic land cover shift that threatens the natural environment, accelerating land degradation. To evaluate and map this phenomenon, two pairs of near-anniversary Landsat imageries, on May 21, 2005 and May 26, 1987, are obtained to perform bi-temporal change detection. Unsupervised classification, due to the deficiency of clear information on land cover in the study area, is performed separately on each image. A post-classification comparison is applied to detect the change between the two images. Change map was created to assess which classes showed the most change. Results show irrigated agricultural land classes have grown in the study site, while rain-fed agricultural fields decreased. Also, urban areas are changing and expanding towards the west. Two reserve ranges in the study area are also deteriorating due to overgrazing. This study provides qualitative and quantitative evidence of land degradation in Northwestern Al Mafraq area that can help policy-makers combat land degradation and control its expansion. |
