Fjölrit RALA - 05.12.1999, Blaðsíða 32

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Desertification in the Mediterranean Europe
lands or urban areas (Perez-Trejo 1992). This trend is locally reversed by subsidies
provided by the European Union’s Common Agricultural Policity (CAP).
Land abandonment is followed by two trends with opposite effects:
• Natural reforestation and expansion of forest and shrubs. These process drives
the ecosystem towards recovery.
• Expansion of overgrazing encouraged by CAP subsidies drives, the system to
acute degradation and desertifícation. Both cattle and small animals numbers
have increased substantially during the last decades.
Intensifícation of irrigation has increased water consumption in many areas beyond
aquifer recharge rates. This situation subjects the lowlands to chemical degradation
and ground water depletion. Finally, sharp increases in tourist population constitutes a
tremendous increase of human pressure on environmentally sensitive areas (ESA).
RESEARCH ACTIVITIES
For over a decade, the European Commission has recognised desertification as a ma-
jor problem in the Mediterranean Europe and has supported research on its causes,
impacts, spatial extend and mitigation. Multinational and multiphase integrated proj-
ects have been and are being conducted. These include MEDALUS I, II and III
(Brandt and Thornes 1995), EFEDA (Bolle 1993), DEMON (Lacaze et al. 1995), and
ARCAHEOMEDES (van der Leeuw 1995). Conferences were organised where the
results were presented. A brief account of the scientific advances made so far is given
below:
• General circulation models applied in the area show global warming will
cause increase in temperature and decrease in rainfall.
• Satellite spectral data integrated with digitised geographic information sys-
tems can be used to fill some of the gaps in existing knowledge.
• Dynamic, physically based, multimodular integrated models have been devel-
oped and tested in the field. They can be used to delineate desertification envi-
ronmentally sensitive areas (DESA) and to design mitigation schemes, wher-
ever accurate and adequate data are available.
• Historical pattems of population and land use trends have been examined in
some areas.
• Salt water intrusion in coastal areas and remedial practices have been tested in
the field.
• More data are required for the accurate evaluation of the desertification risk
and for combating it.
The Intemational Conference on Mediterranean Desertification, held in Crete in
October 1996 has concluded that:
• Desertification in the Mediterranean Europe deserves special attention by the
people, the local, regional and the international authorities.
• Significant knowledge has been accumulated, but there gaps in indices, scal-
ing the phenomenon and regionalization of model applications. Most serious
gaps exist in socio-economic issues.