MAPPING DESERTIFICATION, A HIGH EDUCATION COURSE IN REMOTE SENSING

The participants to this Course of high fort-nation are researchers from Algeria, China. Egypt, Italy, France, Belgium, England, Morocco, Mauritania and Tunisia, guided by teachers from Algeria, Belgium, England., Egypt, Italy, France, and Tunisia. The program has previewed conferences about the phenomena of the desertification. some guided visits, projects of fight against the desertification, projects about the conservation of natural resources. The programme included also practical guided work on the field. related to survey systems mainly based on images from satellite, in order to obtain maps to support the land planning. The works have been followed by a general discussion that allowed to reach the following conclusions: The desertification is an universal phenomenon, it exceeds the frontiers of the different countries, hundreds million of persons all over the world are directly touched: Scientific research has an important role and must be oriented toward the applicative aspects in a strict relation with the demands of development. A reliable information in constant modernization is a necessity and a guarantee for the long-lasting management of the natural resources. The techniques of survey, particularly remote sensing, as well as geomatic, constitute privileged ways in order to control the desertification and to support the necessary decisions. Indeed, these techniques allow to measure the impact of the phenomenon on the people and on the natural environment. An interdependent and international partnership has primary importance, particularly in the field of the inventory, and in the control and the evaluation of the land deterioration in barren zones. A general visit crossed the various landscapes units along a route of more than 200 km. This first contact with the land was indispensable in order to understand better several aspects of the barren environment. The successive field surveys were based on a detailed cartography. whose objective was not limited to the level of the apprenticeship of the cartographic survey methods. It was also necessary to realize maps easily employable by the people in charge of the fight against the desertification. In this context the participants have been subdivided in three groups of various nationalities and various disciplines. Each group was responsible for a specific field of study. The thematics developed for the detail surveys have been: Taking advantage of the images from various satellites, with various ground resolutions (MODIS, 250 in. ASTER, 15 m, Quickbird, 0.6 m). Surveyed for land use maps and sketch maps about morphodynamics and field vulnerability, for the entire zone of study and each representative test area. Annotations and discussions have been organized for each phase, in order to draw the necessary conclusions, to understand the dynamics of the country and to realize the local thematic cartograph whose objective was not limited to the level of the apprenticeship of the cartographic survey methods. Participants have developed the job in a homogenic group and with professional conscience, but also challenging the difficulties that they encountered (accessibility of the land, sandstorms, rains...). After the surveys the jobs were displayed in the center and the results of each group was presented in front of a "jury" composed by teachers, the members of the other two groups and also local personalities and experts, and finally by specialists invited for this occasion.