Diversity and conservation of the Gredos Regional Park peatlands (Iberian Central System, Spain): Geomorphological and geobotanical characterisation and incoming threats

Abstract

High-mountain peatlands are essential ecosystems for habitats, biodiversity, water, and carbon cycling, butthere is little comprehensive information in central Iberia. We present results of research concerning the distribution,geormorphology, floristic, geobotany, and habitat diversity of peatlands in the Gredos Regional Park (Iberian Central System).We identified 72 peatlands covering 117 ha and ranging in size from 0.01 to 17.34 ha. Peatlands occur primarily in theupper orosubmediterranean bioclimatic belt at 1775–2230 m asl. From a geomorphological point of view, 9 differentpeatland typologies have been defined. Multivariate analyses (agglomerative cluster analysis and principal componentanalysis) of 103 relevés allowed us to classify the sampled peatland stands into 7 plant communities and 4 Europeanhabitats that formed along complex hydrogeomorphic conditions, and to propose a new subassociation of other communitypreviously described (Caricetum echinato-nigrae lycopodielletosum inundatae). The main threat to Gredenseanpeatlands is pastoral pressure, which affects 15 of them intensively, mainly between the upper supramediterranean andthe lower orosubmediterranean bioclimatic belts (~1314–1700 m asl). Seven bryophytes and three vascular plantsdocumented in the Gredos Regional Park peatlands are included in the IUCN Red List. From the point of view ofconservation priority, the most threatened correspond to transition mires communities (Habitat 7140) growing inoligotrophic and minerotrophic peatlands (Caricion nigrae vegetation). Particularly, the Iberian Central System endemicSedo lagascae-Eriophoretum latifolii association is the one that has achieved the highest score in the five criteriaconsidered in this regard because Meesia triquetra, a species with the category of “critically endangered”, inhabits it.