Laboratoire développement durable et dynamique territoriale, département de Géographie, Université de Montréal/Faculté des Arts et des Sciences, C. P. 6128, succursale Centre-ville Montréal QC H3C 3J7, Canada
In countries with arid and semi-arid climate such as Tunisia, the over-exploitation of ground water resources became intolerable, in particular that of the delegation of Foussana located in the mid-west of Tunisia, object of this study. This situation of overexploitation requires the characterization of the agricultural landscape and the characterization of water resources using a Geographical Information System SIG: ArcGis 9.3. The approach followed in this work is articulate on the installation of an agricultural and hydrological database; these plans of information were combined by methods of multicriterion analysis through the software ArcMap 9.3 to produce cards sets of themes which make it possible to describe the agricultural landscape in this area and to represent the hydrological potentialities of Foussana. Spatialization presents one of the best approaches to characterize the landscape of the area. Thus, this work enabled us to traverse the territories while revealing the wealth in water resources which present a factor supporting the differentiation of the agrarian landscapes in a typology of "rainfed agriculture" (83.4%) and of "modernized agriculture" (16.5%) requires large amounts of water. The irrigated area accounts 179.6 ha (between cultivations of cereals, arboriculture, truck farming and fodder) in 1980, to attain 4620 ha in 2010, for example the apple orchard landscape very demanding of water factor, which accounts for 50% of arboriculture sector in the study zone.
The study was conducted during 2013 in Bouchebka, located in the central west of Tunisia.Such territory has a typical landscape of the transfrontier region. The series of the forest in Bouchebka is a part of the great mass of Aleppo pine. It is distinguished by the importance of the forest area which covers 92 % of the surface area (19,700 ha). The study attempts to inventory the natural vegetation and characterize ecological terms while highlighting the importance of environmental conditions. The method is based on a phytoecological analysis to quantify the floristic richness and diversity of the ecosystem in the forest of mountains in Bouchebka on the basis of floristic surveys and transects distributed in a stratified, systematic sampling in different vegetation formations that were previously distinguished. Statistical analyzes were performed using the Factorial Correspondence Analysis (FCA). The results show that the forest is composed primarily of the Aleppo pine trees, these forests are characterized by the abundance of young feet (10-25 cm diameter class). The ecosystem includes 12 families and 17 genera, 26 species. Thus the study has identified that the biological spectrum of the study area is characterized by a clear dominance of shrubs (41%) and chamaephytes (32 %). The distribution of plant species is influenced by ecological features of the region: the results show that 82% of species are drought tolerant which shows the arid environment. The region is also characterized by its windy side: 32% of species spread via anemochory. Factor analysis showed a pastoral aspect in the study area, with a presence of cultured human action exerted on the forest land species. Phytological spectrum indicates a predominance of woody species reflecting a territory dominated by open grassy areas, predominantly reflecting an arid climate.