Landscape diversity and naturalness in Andorra, a mountain country under contrasting change of land use

Ninot Josep-M., Carreras Jordi, Carrillo Empar & Ferré Albert

Dep. Biologia Vegetal, Univ. Barcelona

Based on the habitats standardised in the Corine Biotopes Manual, we have mapped the landscape of Andorra at the 1:25,000 scale. In the methodological aspect, stand out the use of colour and infrared orthoimages, the rather precise definition of the habitat units, and the handling of all the cartographic information by means of the GIS ArcInfo. The raw result is a detailed map of the area divided into some 3,000 polygons, and identified by 103 legend units from which some include a sole main habitat whereas others contains two or more habitats.

Diversity, naturalness, endemicity, rarity, etc., of each habitat have been evaluated a priori, and then combined with site features (topographic parameters from cartography) to yield a global evaluation for each legend unit. This enabled us to produce a map showing a few levels of natural interest in the landscape of Andorra, and to draw the attention to main tendencies of change, when compared with previous data from the same area, or with similar Pyrenean valleys. Whereas most extensive units (woodland, etc.) show raising extension and naturalness, some rare habitats (fens, riparian forests) appear fragmented or degraded, and seminatural units depending on traditional land use (meadows, dry pastures) are doomed to vanish.