Surveillance des sols dans l'environnement par télédétection et systèmes d'information géographiques = Monitoring soils in the environment with remote sensing and GIS

Intensive rural development programmes coupled with state creation have engendered the remarkable transformation of many rural communities into rapidly growing urban centres in Nigeria. Most affected are the small towns which became the capitals of the new states. Makurdi, the capital of Benue State, is one of them. Makurdi and its environs were studied to assess the land use changes that had occurred between 1967 and 1980 for which the photographs were available. The study revealed that the use of remote sensing data with particular regard to soil conditions have been insufficient or non-existent in planning urban development in Makurdi. The sub-urban town had expanded rapidly with much of the development spilling into the Benue River floodplain, which contains the best agricultural soils. The floodplain soils are vital for dry season cropping and hence food production for the town. The conversion of good agricultural land to urban dwellings and other non-agricultural uses is not peculiar to Markudi town as other newly created state capitals are equally affected. Therefore, the situation calls for loca, state and national policies on comprehensive land use planning in developing urban centres so as to protect vital agricultural lands, such as floodplain (or fadama) against other competing uses, especially in the sub-humid and semi-arid regions of Nigeria. (Résumé d'auteur