Environmental Analysis of Land Use and Land Change of Najran City: GIS and Remote Sensing

This study critically analyzes changes in land use and land cover by means of multi-temporal remote sensing of Najran City in Saudi Arabia between 1975 and 2019. A number of remotely sensed data were employed to create multi-maps using: (a) the normalized difference vegetation index; (b) head-up digitizing; and (c) supervised classification of Landsat images using field observation and accuracy assessment, including field verification and Google Earth Professional. Criteria from a well-known technique of environmental assessment, the Building Research Establishment Environmental Assessment Method (BREEAM), were used to critically analyze land use and evaluate levels of sustainability, with particular focus on ecology. Therefore, land around Najran can be characterized as follows: (1) Najran valley; (2) agricultural land; (3) built-up areas; (4) reclaimed land; (5) basement rock; and (6) desert. The results indicate that agricultural land grew from an average of 39.81 km² (1.07%) in 1975 to 218.51 km² (5.9%) in 2005, although this was followed by a marked decline between 2005 and 2019. Urban land increased from 1.12 km² (0.031%) in 1975 to 154.35 km² (4.13%) in 2019. Furthermore, there was approximately 1289.47 km² of reclaimed land in 1975 (i.e., 34.64% of the total area study area) but approximately 1151.1 km² (30.86%) in 2019. There was a small amount of desert (i.e., sand dunes) in the study area, and no change was recorded in the basement rock. This study analyzed these land changes, likening them to BREEAM criteria of ecology and land use. A number of unsustainable practices were potentially resulting in serious land contamination and pollution of both surface and ground water, as well as an increased risk of flooding.