Wetenschap - 28 november 2002

High-tech and local knowledge can go hand in hand

High-tech and local knowledge can go hand in hand

Enlargements of aerial photographs are accompanied by maps sketched by local people in research carried out in Burkina Faso. High-tech instruments, such as Global Positioning Systems (GPS), help to link the two kinds of maps from such different sources.

Regional government planners in Burkina Faso make use of geographic information systems (GIS) when planning how natural resources should be used. However, they also recognize the importance of building such planning upon local people's perception of their natural environment. PhD researcher Laurent Sedogo developed a method to use the results of participatory rural appraisals within GIS. The method proved satisfactory; Sedogo checked the information local people gave on the state of natural resources against other information from aerial photographs and existing data. People were asked for example how high the water level rises when there are floods, and the water levels they gave correlated for ninety percent with the data already stored in a GIS system.

Linking local information with aerial photographs and GIS can benefit the local people as well. Sedogo did participatory studies on conflict between pastoralists and agriculturalists in Burkina Faso. Often conflict arises over grazing land, which can be solved when both groups agree on the use of land in clearly defined areas. In a participatory method local people are asked to sketch maps of their environment, in order to understand how local people perceive the environment. Sedogo then introduced enlargements of aerial photos in order to link the local people's maps with the real situation. Global Positioning Systems could then be used to mark in the landscape boundaries that had been drawn on the maps. Sedogo stresses that aerial photographs and other technologies are just tools to support the processes of negotiation among local people about the use of their natural resources.

Laurent Sedogo defended his PhD on 22 November. His promotors were Professor Eric Smaling, professor of Soil Inventarisation and Land Evaluation at Wageningen University, and Professor Andrew Skidmore, Chairman of the Department of Natural Resources, ITC, Enschede.

Joris Tielens

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