Living Land

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Reclamation and sustainable development

of degraded lands in the Niger basin

Seyni Seydou, Project Coordinator, Niger Basin Authority and Laouali Garba,

Principal Environment Officer, African Development Bank

he catchment area of the Niger River covers 2.2

million km² (with an active basin of 1.5 million

km²), crossing four agroclimatic zones successively

in nine West and Central African countries: Benin, Burkina

Faso, Cameroon, Chad, Côte d’Ivoire, Guinea, Mali, Niger

and Nigeria. The entire basin is characterized by a general-

ized degradation of its natural resources and it is affected

to varying degrees by water and wind erosion and siltation.

In this highly differentiated bioclimatic context lives a popu-

lation estimated at 113 million inhabitants in 2005, more

than half of the population of the nine countries of the Niger

basin. The Niger River is therefore of vital importance to the

socioeconomic advancement for the nine basin countries. The

realization off this is unfortunately compromised by climatic

and anthropogenic factors.

Four parallel stripes are commonly distinguished in the

climate from south to north of the basin. These are the

humid tropic zone, with over 1,200 mm of average annual

rainfall; the subtropical zone in the dry season, called the

‘Sudanian zone’, with an average annual rainfall between 800

and 1,200 mm; the long dry season subtropical zone, called

‘Sahel’, with an average annual rainfall between 100 and 800

mm; and the subtropical desert, called ‘Sahara’, with very

irregular or near absent annual rainfall of less than 100 mm.

The physical and chemical constitution of the geological

bedrock of the Niger basin is the basis of arenization and

sand. Transported and deposited by water and wind paths,

it is the major cause of the silting up of the Niger River.

The climate is the main factor in the production of sand

by dissolving rocks with moisture, through their cracking

with temperature differences, by their disintegration (soil)

Image: AfDB

An awareness session in Sembé village, Mali

iving

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