Salt accumulation in topsoils of irrigated maize fields in comparison with irrigated rice fields in Kilimanjaro region, semiarid Tanzania

Abstract

The current food crisis in Sub-Saharan Africa can be explained partly by the under-development of irrigated agriculture (Shapouri et al. 1986). However, the high cost for the development of irrigation systems makes the expansion of irrigated areas difficult in this region (FAO 1984). Apart from the problems of economic viability, irrigation in the semiarid region of Africa requires special attention to protect the soil from salinization. During a volcanic ash soil survey tour in the Tanzanian highlands (Mizota et al. 1988) we had the opportunity to observe and compare the effects of irrigation on the accumulation of salts in topsoils between lowland rice and upland maize fields. This report describes the advantages of lowland rice in terms of scarce salt accumulation associated with irrigation. While, a poorly drained irrigated maize field showed rapid salt accumulation.

Key Words:

• irrigation
• maize
• rice
• salt accumulation
• semiarid climate