r the 
0d is 
lysed 
| thus 
itions 
ew of 
  
ne 
en 
‘orst 
es 
RW, 
Diarra, Lassine 
  
Computer assisted cartography : a powerful tool for sustainable management of natural resources : Case 
Study of N'Tentoukoro area. Mali. West Africa. 
Paper number : 47 
L. Diarra, Institut d'Economie Rurale (IER) PO Box 258 Bamako. Mali 
E-mail : direction(g)ier.ml 
Key words: Biomass, mapping, sustainability, user requirements 
Abstract: 
L. Diarra, Institut d'Economie Rurale (IER) PO Box 258 Bamako. Mali 
Title :Computer assisted cartography : a powerful tool for sustainable management of natural resources : 
Case Study of N'Tentoukoro area. Mali. West Africa. 
In Mali, like in many sahelian contries, ever-increasing livestock and human population are intensifying the 
demand for grazing and agricultural lands around cities. Fire wood requirements have also increased, since 
wood remains the main fuel for the population. In an attempt to satisfy rising demands for forage, food and 
firewood, large areas of land have been deforested, land cleared and cultivated. Natural vegetation has been 
reduced and degraded around the towns. As a result, the balance between people and their environment has 
disappeared and townspeople are obliged to go to the surrounding villages in order to meet their firewood and 
forage needs. N'Tentoukoro is one of these villages in which natural resources are overexploited by 
woodcutters and foraging transhumant cattle . This overexploitation has forced local cattle to leave the 
watershed to satisfy their forage needs during the dry season. Consequently , there is not enough manure 
produced in the village, and soil fertility has decreased. Due to the lack of this key ressource, crop production 
has reduced and farmers are getting poorer and poorer. To diminish their poverty, many people, especially 
women, collect and sell firewood. 
Land degradation and depletion of soil fertility threaten sustainable increases in agriculture and endanger the 
survival of present and future generations. To stop this degradation, sustainable natural resource management is 
necessary. This can be done by generating information on natural resource base, to be compared with the needs 
of the population and their livestock. Therefore investigations have been made in the watershed to evaluate 
forage and crop prodution , forest productivity, and also map the main vegetation units. 
Aerial photographs from 1995 were used to map the vegetation units in the watershed. Herbaceous and crop 
residue biomass were measured using a stratified random sampling technique. Standard measures of leaf production 
and forest productivity based on research results were used to evaluate forests productivity and browse production. 
Investigations were conducted to determine households" firewood consumption and the rate of wood removal from 
the forest. Carrying capacity was estimated by season on the basis of forage quantity and quality and animals 
requirements. 
The study gives a description of the mapped vegetation units of the watershed (units extent, vegetation cover, forage 
production, carrying capacity) , households’ firewood consumption and forest productivity. Comparing demand and 
supply of forage shows that grazing lands are over exploited especially during the beginning of the rainy season 
where stocking rate is four times the carrying capacity of the land. Households’ firewood needs are satisfied but the 
pressure put on the forests to meet the ever increasing needs of the townspeople is worrying. 
Suggestions for improving soil fertility, forage availability and balance for forest exploitation are made. 
  
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000. 363