Monitorización de la Biodiversidad vegetal y sus distintos componentes en un parque nacional de montaña

[EN] National Parks, and mountain parks in particular, are biodiversity reservoirs, and constitute very suitable areas for monitoring changes in species abundance, richness, and community composition. Our project has been carried out in the Ordesa and Monte Perdido National Park, a topographically complex area that shelters about 1400 vascular plants belonging to biogeographically contrasted groups: from Mediterranean to boreoalpine. Despite part of the Park has been protected for about 100 years, it is not safe from global factors affecting other mountains, like climate warming and shifts of land-use. This project had two main objectives: 1) to characterize the spatial diversity of the Park from different points of view besides classical richness, and 2) to describe the dynamics of plant richness and community structure in the richest areas of the Park: alpine pastures, and their limit with the subalpine forest. We first analysed the distribution of more than 44.000 records of vascular plants, georeferenced at a 1 km 2 scale, and estimated diversity using different approaches: species richness, phylogenetic diversity, and abundance of vulnerable plants. The most representative and distinctive areas were also identified, considering the whole flora of the National Park. Richness was also correlated to different biotic and abiotic variables in the Park. Sampling effort was included in that correlation to avoid bias due to the number of prospections at each place. It was estimated from a new model we generated (FIDEGAM), and served to correct for the uncertainty of richness estimations. FIDEGAM can be used for any other database, in order to correct for bias in biodiversity analysis. The second objective was undertaken by relocating and resurveying the same places studied 10 (ecotone Pinus uncinatapasture) and 20 years ago (6 pastures located between 1900-2750 m.a.s.l.). At the ecotone, a slight increase of the forest has been detected, with no consequences on the structure and composition of the herbaceous layer yet. In the pastures, a slight increase of graminoids was also recorded. Overall, the project served to identify the most interesting areas of plant diversity from different points of view (not always overlapped), and establish permanent plots for monitoring the impact of global change on mountain biodiversity.

Queremos mostrar nuestro agradecimiento al Parque Nacional de Ordesa y Monte Perdido, y especialmente a Elena Villagrasa y Ramón Antor por facilitar el trabajo en todo momento. A Pedro Sánchez, María Jarne, Jesús Villellas, Gabriel Sangüesa y Marc Talavera por su ayuda en la toma de datos en campo durante el desarrollo del proyecto. Financiación recibida a través del Organismo Autónomo Parques Nacionales (Referencia del proyecto: 018/2008).

Peer Reviewed