University of Vaasa - Vaasan yliopisto

Figure 1: ICRISAT regional presence.
ICRISAT Activities– Three Case Examples
Case 1. Soil improvement in Senegal (ICRISAT 2008)
High soil salinity is one of the biggest hurdles to successful agriculture and
environmental development in many places in the Semi-Arid Tropics. There are two
main causes: 1.) the over-use of irrigation water coupled with lack of appropriate
drainage, such as in the irrigated lands alongside the Senegal River, and 2.)
salinization by seawater that moves inland. Senegal’s coastal zones are low, and
ocean tides can flow more than 100 km upriver – about one million hectares of arable
land have been made unusable this latter process. But change is afoot.
A method for reclamation of saline soils was developed by a joint research team of
Institut Sénégalais de Recherche Agricole (ISRA), the University of Dakar and
ICRISAT. The first stage involves erecting high earth ridges circling an area,
creating basins that retain rainwater. The rainwater in turn permeates into the soil and
leaches away surface salt. The basins can be planted with a salt- and water-tolerant,
fastgrowing tree type, Tamarix aphylla var. erectus. The tree has an economic value
– producing very hard timber suitable for tools and quality furniture – but the trees
furthermore suck up moisture from the deeper stratas of soil, allowing new rainwater
to filter down faster.
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