Geodiversity of closed depressions in a high relief karst: Geoeducation asset and geotourism resource in the 'Sierra de las Nieves' National Park (Málaga Province, Southern Spain)

Abstract

Closed depressions are scale-invariant landforms that are the most distinctive and characteristic landform in karst terrains at the millimetre-to-kilometre scales. The purpose of this paper is twofold. The first is to raise awareness of the geoheritage and geoeducational asset provided by closed depressions in a high-relief karst massif with the objective of promoting geotourism in the Sierra de las Nieves National Park in Southern Spain, which was declared a national park in 2021. The second is to propose a general, sound methodological approach to achieve the first purpose that can be applied to other national parks and geoparks with karst terrains. This paper identifies the factors that generate geodiversity in closed depressions in karst and, although dissolution is the primary generator in the high relief karst massif analysed, five distinctive types of natural, closed depressions have been recognized and described together with particular cases that deserve consideration. A sixth type of closed depression comprises anthropic closed depressions. Lithology and tectonics are the two main geological factors that determine the different types of natural closed depressions. Closed depressions add value to the geomorphological and hydrogeological diversity of karst terrains, and they can be used at various levels both off-site and on-site for preparing exhibits at a visitor or interpretation centre; as a story resource for guided field tours; and for identifying geosites of special interest for geological itineraries. Generating interpretation methods is an important component of transferring scientific knowledge of, and interest in, karst landscapes to the various types of visitors to the recently declared Sierra de las Nieves National Park in Andalusia, Southern Spain. In addition, an extensive inventory of closed depressions can be used for their identification, mapping, conservation, protection, and management. Such an inventory, which can be obtained efficiently from high spatial resolution digital elevation models, also contributes to the promotion and dissemination of geomorphological science to the general public.

Keywords

• closed depressions
• doline types
• sinkholes
• geodiversity
• geoheritage
• geotourism