uvalas

Uvalas (singular uvala) are large, closed depressions formed in karst landscapes where soluble rocks such as limestone or dolomite are dissolved and small dolines merge into a wider basin. The term is used in karst geomorphology, particularly in the Western Balkans and surrounding regions. Uvalas typically occur as elongated or irregular basins with relatively flat floors and steep, uneven margins that reflect their multi-doline origin. Sizes commonly span hundreds of meters in width, and depths are often tens of meters, though variability is high.

Formation and structure: Uvalas develop when multiple dolines coalesce or when subsidence enlarges a depression within a carbonate bedrock. Over time, surface runoff and, in many cases, underground drainage through cave systems help shape the basin and its margins. Sediments may accumulate on the floor, supporting soils, vegetation, and wetland features.

Hydrology and ecology: Many uvalas collect surface water and host seasonal or perennial ponds, lakes, or wetlands. Their hydrology is closely linked to the karst drainage network, with water sometimes disappearing underground through cave passages. The basins can support diverse plant and animal communities and may serve as important local habitats and water resources.

Distribution and significance: Uvalas are characteristic of the Dinaric karst and other carbonate regions of Europe, but similar closed depressions occur in other karst landscapes worldwide. They are studied in geomorphology, hydrology, and ecology and contribute to understanding karst development, landscape evolution, and regional biodiversity.