The study presented in this paper has been developed with the perspective of generating long term development plans for a network of domestic airports. As a first step towards this objective, the problem of generating long term predictions of demand for a network of domestic airports is considered. This is a step towards the objective of producing long term capacity investments plans allowing to manage adequately a network of airports. Then the different demand flows at airports which are relevant to characterize the need for new airport facilities and upgardes in capacity, are analysed and compatibility constraints between these flows introduced. An appraisal is realized about the basic data necessary to perform these network demand forecasts. A sequential scheme is proposed to generate in a coherent way predictions of the different dimensioning networks and airport flows. Passenger, freight and aircraft flows from and to external airports are also considered in this study.

This article analyses the dynamics land use in the Lake Chad area located in the Extreme East of the Nigerien territory in the region of Diffa. The study was conducted by using the approach “Land-Use and Land-Cover Change (LULCC.” The digital satellite pictures Landsat TM for the year 1990, Landsat ETM for the year 2010 and Landsat ETM for the year 2018 were used. The analysis of the soil occupation indicated some significant changes of the milieu. The food and market gardening crops produced during the period of low tide are abandoned because of insecurity in the lake’s bed. The first unit of soil occupation in 1990 with 31% of coverage rate, covers, in 2018, only 1.26 % of the surface taken into consideration. At the same time, the vegetations (dense enough and thick) with Prosopis juliflora in the Lake’s bed expand and densify more because of the improvement in rainfalls in the area in recent years. The dynamics is also observed with the installation of pluvial crops on more than 19% of the surface taken into consideration at the expenses of the degraded shrub steppes which has lost more than 28% of its surface in relation to that of 1990. The return of the lake waters in the area on a surface of more than 13,000 hectares was added to it. The study also enabled to understand the relation to space of the various rural actors in a context where the access to natural resources is a major stake and the object of competition between users.

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