Poljé del Cubillo

Poljé del Cubillo

A poljé is a karst depression by way of elongated valley and closed with a flat bottom, large size and irregular contours. The edges are steep or craggy, and are covered by the limestone rock. Its origin is due to the dissolution of the carbonate rocks (karstification) and the existence of folds or faults in the karst massif. These structures predispose a zone for the action of the dissolution that gives rise, in the Cubillo poljé, to this depression.

The poljé is usually covered by a seasonal creek or stream which suddenly disappears down a sinkhole or '...'.rapporteurThe 'water supply', in this case, is located at the bottom of the valley that leads part of the water to the Tornero Cave. Due to the relationship with groundwater, seasonal lagoons often form at the bottom of the poljé when the water table is high. The lagunillas del Cubillo are small stationary pools of almost circular contour on relict sands, so that they have become small siliceous 'edaphic islands', surrounded by calcareous substrates.

This conditions the curious presence of various species of siliceous flora in a limestone environment, such as Genista anglica, a type of gorse, or the only known populations in the Park of two species of aquatic plants, Eleocharis acicularis and Littorella unifloratypical of wetlands with a siliceous substrate. We also found at the bottom of the poljé a torca with a permanent gap within which there are populations of protected species of aquatic plants such as Polygonum amphibium and Potamogeton gramineus.

To find out more about this curious poljé del Cubillo we recommend doing the Georuta 8 which brings us closer to landscapes of great value between the towns of Czech y Chequillaor simply come to the town of Czechtake the path of AguaspeñaContinue until you come to a signpost on your right indicating the location of this valley.