The future of the forests in the southern Mediterranean faces a real threat due to the impact of climate change. Climate change reveals itself directly in the form of excessive heat waves in summer, a significant decrease in summer rainfall, mild winters and an extension of the dry season. Indirectly, the ravages of climate change are noticeable through an increase in the number of fires and pest attacks.
Moreover, the lack of alternative management involving local people is accelerating the degradation of natural forests, especially oak trees. For this reason, the National Institute for Research in Rural Engineering Water and Forestry (INRGREF) in Tunisia has included among its priorities a programme for the adaptation of Tunisian forests to climate change. This research programme is composed of three axes: mitigation, adaptation and participation of the local population.
With regard to the mitigation component, although some work has been carried out in Tunisia to estimate carbon reserves, data on the variations in the flows of CO2 exchange between forests and the atmosphere, as well as on the variation of flows with the climate and the availability of water, are still lacking in the research programmes in the southern Mediterranean. For this purpose, a site for observation has been installed in the cork oak forest of Nefza, northwest of Tunisia.
The mitigation potential of forests in the southern Mediterranean is a very interesting topic of discussion. Three parameters will determine this potential for Tunisian forests, that is, on the one hand, the enrichment of the atmosphere in CO2, which is considered to be favourable, and on the other hand, water stress and the low percentage of organic matter in forest soils as unfavourable factors.