The main response of natural Aleppo pine trees to drought has been studied in three sites on the North-western of Tunisia, in order to assess their capacity to adapt to climate change and overcome the water challenge. This research was based on the evaluation of some physiological traits (xylem conductivity, water potential..), the soil moisture, the water content, and the foliar gas exchange (photosynthesis, transpiration, and stomatal conductance).
Aleppo pine is one of the dominant forest species in Tunisia, favoured by its great regeneration capacity, plasticity, climatic stress tolerance, and multiple products: wood, edible seeds, vegetable seed oil, essential oils from leaves. For these reasons it has been used massively as for reforestation.
But the wide geographical distribution of the species might imply variation in adaptive and productive traits. The use of genetic material well adapted to the environment and better performing allows for valorization of the resource and offers a guarantee of success for new reforestation. In this context, selection of the best provenances from comparative trials is an interesting research issue.
Aleppo pine (Pinus halepensis Mill.) is one of the most drought-tolerant pine species and it is distributed over large drought-prone Mediterranean regions. The determination of the water balance of the soil-crop-climate and its fluctuation is difficult to achieve, due to the spatial variation in site conditions (Schiller and Cohen, 1998). The objectives of this study are to (1) estimate crop water requirements (ETc) and actual evapotranspiration (ETa) of Tunisian Aleppo pine and (2) study the impact of climate change on water balance, using the WEAP-MABIA Module (Yates et al.,2005a; 2005b; Jabloun and Sahli, 2012) based on the FAO Irrigation and Drainage publication 56 (Allen et al., 1998).
Aleppo pine seeds (commonly called Zgougou) derive all their originality and nobility from the fact that they are consumed by Tunisians as part of their cooking habits. Zgougou is considered one of the most interesting NWFP due to socio-economic role and commercial value. Aleppo pine seed oil can be extracted as for nutrition, or for medicinal and cosmetic uses.
The present work studies the conditions of exploitation of seeds in the forest, the yield of vegetable oil extracted, its physicochemical qualities and the possibilities of valorizing the press cake obtained after the oil extraction.