Assessing the Soil Quality Index in Northeast Libya and its Impact on Environmental Sensitivity to Desertification through Geographic Information Systems

Abstract

Ain Hizam, Batta, and Taknis, covering a total area of 195,000 hectares. The methodology integrates Geographic Information Systems (GIS) with the Mediterranean Desertification and Land Use (MEDALUS) model. All available soil data were synthesized to calculate the SQI and generate an Environmentally Sensitive Areas Index (ESAI) map for desertification. To produce the component maps of the SQI, the Inverse Distance Weighting (IDW) interpolation method was employed.

By applying seven SQI scenarios and eight ESAI scenarios, the study utilized Weighted Overlay and Sensitivity Analysis, guided by local expertise. The findings revealed that soil quality maps from scenarios 6 and 7 were highly consistent, while significant spatial agreement was observed among maps for scenarios 1 through 5. All SQI scenarios categorized the land into only two classes: high quality and moderate quality.

Regarding the ESAI maps, scenarios 7 and 8 identified two land classes: critically sensitive and slightly critically sensitive. In contrast, scenarios 2, 3, 6, 7, and 8 resulted in a single classification: slightly critically sensitive. Furthermore, the results indicated that assigning a weight of 70-80% to the "surface stoniness" parameter yielded the most accurate results, given the low percentage of gravel and stones in the region’s soil.

The study concludes with a detailed ESAI map of the region, clearly identifying the areas most vulnerable to desertification. It recommends broader implementation of GIS and the MEDALUS model in combating desertification, alongside the development of adaptive localized models to address specific environmental challenges.