Dolines are among the most common landforms in Slovenia – karst depressions up to approximately 100 m wide and around 10 m deep. Numerous interpretations of their morphogenesis and function exist, yet without consistent conclusions. In this study, we examined the morphogenesis and distribution of dolines in Slovenia. Based on a digital terrain model, we delineated dolines across Slovenia. This was followed by morphometric classification, which served as a basis for a systematic approach. We identified four distinct types. Bowl-shaped dolines have gentle slopes with wide flat floors and are most typical in areas of corrosion plains, where covered karst prevails. Well-shaped dolines have steep rocky slopes and small narrow floors and are most characteristic of cone karst areas. Funnel-shaped dolines have mostly gentle slopes and narrow floors, are the most common type in Slovenia, and occur both on corrosion plains and in cone karst. Elongated dolines can be highly variable. One subtype is associated with unroofed caves and is most common in areas where larger rivers sink underground, while the other is characteristic of karst slopes, particularly dolomite cone karst. Detailed field, laboratory, and statistical analyses demonstrated that doline morphology does not indicate their genesis, which contradicts the existing literature. Doline morphology and genesis are also not related to lithological characteristics. Different doline morphologies are not linked to morphogenetic processes but are evidently the result of morphodynamic processes. Morphological differences among dolines indicate varying process dynamics, which is why certain types are associated with specific karst environments. The results demonstrate that the solutional paradigm of doline formation is not empirically supported and requires reconceptualisation. A common characteristic of all analysed dolines is that they are filled with Quaternary aeolian sediment, representing an important archive of palaeoenvironmental data. The findings call for a fundamental reconsideration of the current understanding of karst surface development and the role of sediments within it.
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