Ecological Vulnerability of Lands of Western Kazakhstan: Analysis Based on MEDALUS Model and Remote Sensing

This study focuses on the assessment of the ecological vulnerability of lands in the western regions of Kazakhstan (WKR) using the MEDALUS (Mediterranean Desertification and Land Use) model in combination with satellite remote sensing data. Particular attention is given to the influence of climatic factors, soil properties, vegetation condition, and anthropogenic pressure. As part of the analysis, key indicators were calculated, including the Soil Quality Index (SQI), Vegetation Quality Index (VQI), Climate Quality Index (CQI), and Management Quality Index (MQI). Based on these parameters, an Environmental Sensitivity Area (ESA) index was developed, allowing the classification of the territory into five vulnerability classes ranging from low to critical sensitivity. The results indicate that 52.7% of the territory of the WKR falls within the high-risk zone for land degradation. The most pronounced changes were observed in the southern oblasts of the region, particularly in Mangystau oblast (MAN), where 98.7% of the land is classified as degraded and 74.3% of the territory falls under the category of extremely high ecological vulnerability. In addition, a steady decline in precipitation levels has been identified, contributing to the intensification of aridization processes across the region. Correlation analysis showed that the strongest relationships with the final ESA index were observed for the Vegetation Quality Index (VQI) and Climate Quality Index (CQI), both with correlation coefficients of r = 0.93 and an average coefficient of determination R2 = 0.87. The Soil Quality Index (SQI) also demonstrated a strong correlation (r = 0.86). In contrast, the Management Quality Index (MQI) exhibited a generally weak correlation, except in the MAN oblast, where within the Very Low Quality (VLQ) class areas, it showed a moderate correlation (r = 0.68, p < 0.0001). The results highlight the critical role of natural factors—particularly vegetation condition, climate, and soil quality—in shaping the ecological vulnerability of the region. Findings emphasize the need for a comprehensive, multi-criteria approach in developing strategies for sustainable land management under conditions of ongoing climate change.