Urban expansion and shrinkage of vegetation cover in Al-Balqa Governorate, the Hashemite Kingdom of Jordan

Abstract

The study investigates the spatio-temporal dynamics of urban and vegetation in Al-Balqa Governorate/Jordan. Landsat Thematic Mapper Landsat 5 (1996) and 8-OLI (2018) were downloaded from the United States Geological Survey (USGS), covering a period of 22 years. Supervised classification methodology has been employed using the maximum likelihood technique in GIS.10.5.2. The images of the study area were categorized into four different classes: vegetation, built-up area, barren area, and bodies of water. Normalized difference vegetation index (NDVI) was applied at a threshold value ≥ 0.1 to distinguish between the vegetated area and non-vegetated areas. The results showed that the vegetated areas at NDVI value threshold ≥ 0.1 decreased by 12.18% during the period 1996–2018. The built-up area expanded from 4.53 to 9.29 km2 during the study period. The result indicated that a large amount of the rainfed area was replaced by urban services and barren land. This shift took place, where the mountainous region and Mediterranean climate prevail, which represents the best environment for rainfed agriculture, especially olive trees. The study recommends that more attention should be paid to protecting the agricultural area and suggests the need for better planning and management to balance between vegetation and urban area expansion.