Vegetación, patrón espacial, y caracterización topográfica de las hozaduras de jabalí en los pastos supraforestales del Pirineo Central

Vegetation, spatial pattern and topographic characterization of wild boar rooting in supraforestal pastures at the Central Pyrenees.

Fall of human population in mountain areas, abandonment of traditional practices, and absence of predators have caused, in the last decades, a considerable increase of wild boar populations and a spectacular expansion of its distribution area, as much in our country as in other territories of Europe.

Wild boar rooting affects to a broad environmental spectrum that includes cultures, riversides, scrubs, forests and pasturelands, from the sea level to more than 2000 m. of altitude. From an economic point of view, wild boar inflicts remarkable losses by destruction of harvests, reduction of pasturing areas and visual deterioration of some landscapes, specially in protected areas. From an ecological perspective, rooting constitute one of the main animal disturbance and originate processes in vegetation of different scopes: biomass diminution and primary production, hollows production in vegetation with opportunity for pioneering species, shifts in floristic composition and diversity, etc.

Within the framework of a Ph.D. that intends to study the impact of the wild boar in supraforestal pastures, we now analyze in the Valley of Aisa (Western Pyrenees of Huesca) the space distribution rooting patterns to value its territorial affection and to characterize its occurrence in relation to topography (altitude, aspect and slope), accessibility and type of pasture.

Disturbances appear in an aggregated pattern of spatial distribution, showing preferences by a wide altitudinal rank (1533-2244 m), gentle slopes (0-37º) and southwestern dominant aspects. Pastures grazed with greater intensity seem to be favourites at grubbing time, whereas, at the other end, zones located to greater altitude, with smaller degree of accessibility, little vegetal cover, strong slopes, seem to constitute the less favourite zones.