## 5 Discussion
### Factors Influencing Sinkhole Formation  
The geological and tectonic factors, which are one of the five main factor groups, have emerged as the most influential in sinkhole formation. As explained in detail above, PTF has been identified as one of the key factors, indicating that sinkhole occurrence significantly increases in areas close to fault lines. As emphasized by [102], fault lines increase weakness zones in karst units, reconfigure groundwater flow paths, and accelerate dissolution processes, ultimately triggering karstic phenomena. Additionally, LTG has been associated with high susceptibility levels in areas dominated by carbonate rocks. The susceptibility of carbonate rocks to dissolution leads to more frequent sinkhole occurrences in these regions [45; 99]. These findings align with the observed distribution of sinkholes in the study area. Furthermore, a negative correlation was observed between lithology (LTG) and elevation (ELV), suggesting that sinkhole formation is more prevalent in areas with lower elevations and specific lithological characteristics. This finding is consistent with previous studies that have highlighted the role of lithology and elevation in controlling sinkhole susceptibility [4; 52]. Hydrogeological factors serve a critical role in explaining the nonlinear effects of the model, clearly demonstrating the impact of changes in GWL and GWD on karst processes. Particularly, DBC has been identified as the most influential variable among hydrogeochemical parameters in the SHAP analysis. It is known that differences in bicarbonates, which influence carbonate solubility, accelerate karst processes and lead to sinkhole formation [107]. Similarly, other hydrogeochemical variables, such as DDO and DPH, indicate that changes in the chemical balance of groundwater trigger karst processes. These findings highlight the role of hydrogeochemical processes in sinkhole formation within karst systems. Additionally, the strong positive correlations observed between chloride (DCH), magnesium (DMG), and sulfate (DSU) concentrations suggest that these ions play a significant role in the dissolution of carbonate and evaporitic rocks. Magnesium, in particular, accelerates the dissolution of carbonate rocks, while chloride and sulfate ions increase the salinity of groundwater, further enhancing the dissolution process [2; 99]. These findings align with previous studies that have emphasized the importance of hydrogeochemical processes in sinkhole formation [100; 104]. Furthermore, a negative correlation was observed between pH (DPH) and bicarbonate (DBC), implying that a decrease in pH levels may reduce bicarbonate concentrations, which in turn can accelerate the dissolution of carbonate rocks [103; 104]. This finding is consistent with previous studies that have highlighted the role of pH in controlling the solubility of carbonate rocks in karst systems. Moreover, a negative correlation was identified between potassium (DPT) and pH (DPH), suggesting that an increase in potassium concentrations may lower the pH of groundwater, creating more acidic conditions that enhance rock dissolution [100; 101]. These findings underscore the complex interplay between hydrogeochemical factors in sinkhole formation and highlight the importance of considering these interactions in susceptibility assessments. Topographic factors have a significant role in determining the spatial distribution of sinkhole formation. Variables such as ELV and SLP have shown moderate importance in the SHAP analysis. These findings indicate that karst processes are generally more active in areas with lower elevations and shallow slopes. Especially in areas with mild slopes, the accumulation of water and its infiltration into the ground can accelerate karst dissolution processes [2]. Furthermore, factors related to water flow, such as PDR and SPI, illustrate the impact of surface waters on the dissolution of karstic rocks.