Context and objectives
Lowland valleys are depressions with specific soil characteristics, which are flooded during a certain period of the year. Although having an important agricultural potential, they are frequently exploited below their potential in West Africa. Mapping the current land use in these depressions, producing maps for ‘agricultural suitability’ and integrating these data and other local data in a geographic information system (GIS), can contribute to agricultural development and to an increasing agricultural production in these areas.
The mapping includes a land use classification, a zonation in agricultural suitability in relation with soil humidity and an identification of the zones needing management measures, which are function of the population pressure and the deficient climate factors.
Purpose of the study : evaluation of the scientific, technical and economic feasibility of the mapping of lowland valleys in West Africa. The Comité Inter-Africain d’Etudes Hydraulique (CIEH) asked for this study in the context of a financing request for a large ‘lowland valley mapping’ project, to be put forward to international organisations.
Expected scientific results
For a study region with a surface area larger than 600 km2, the remote sensing methodology becomes economically more interesting than the conventional
method (interpretation of aerial photographs and terrain measurements).
Two important constraints need to be fulfilled :
(1) the use of computerised image processing techniques
(2) the availability of a remote sensing expert having good terrain knowledge of the study area.
Risk : the availability of appropriate good quality images (right period, cloud free).
The inventory of lowland valleys in Cameroon and Nigeria is not possible because of the unavailability of good quality satellite images.
|Project leader(s):||ULg - Gembloux Agro-Bio Tech - Echanges Eau-Sol-Plante|