SOUTHERNMOST HIGH MOUNTAIN LAKES IN EUROPE (SIERRA NEVADA) AS REFERENCE SITES FOR POLLUTION AND CLIMATE CHANGE MONITORING.

This paper summarize, from a regional limnology point of view, some of the identifying characteristics of Sierra Nevada high mountain lakes, as a result of the studies carried out by the limnology group of the University of Granada since 1975. A overall narrow variability in the morphological, physical and chemical characteristics of this lakes seems to appear as a conse-quence of a smaller and more homogeneous distribution area than high mountain lakes of other mountain ranges (¡.e. the Alps) cover. The position of Sierra Nevada, far away from industrialized areas, keep their water bodies free of air pollution which reflects in the relatively high levels of alkalinity compared with other mountain lakes under acidification processes (Le. Norwe-gian ones). Likewise, their southern position makes the Sierra Nevada high mountain lakes ideal reference sites for climate change monitoring. The homogeneity in their abiotic environment is responsible of a limited biological diversity of their plank-tonic communities. The phytoplankton is dominated by nanoplanktonic species and the zooplankton is only composed by 20 roti-fer species, 8 cladocerans and 5 copepods. All these characteristics underline the interest of Sierra Nevada lakes as subject of scientific research both applied as in a purely theoretical plane