Article

Droughts in the Sudano-Sahelian Ecological Zone of Nigeria: Implications for Agriculture and Water Resources Development

Global Journal of Human Social Science (B): Geography, Geo-Sciences & Environmental 01/2013; 13(2):1-11.

ABSTRACT This study evaluates the extent and degree of severity of droughts in the Sudano-Sahelian Ecological Zone of Nigeria using rainfall data spanning a period of 60 years (1949-2008) for eight meteorological stations in the zone. The Normalized Rainfall Index was used in depicting periods of different drought intensities in the region. The results revealed that the zone was characterized by larger extent of severe drought since the beginning of 1968 through the early 1970s, and then the 1980s in which the drought was so severe than any other decade in the study period. The late 1990s and the 2000s on the other hand have been witnessing a decrease in the number of drought occurrences in the zone. The mean absolute probability of mild, moderate and severe droughts for the zone was 0.13 (recurrence interval of 7.7 years), 0.11 (recurrence interval of 9.1 years), and 0.08 (recurrence interval of 12.5 years) respectively. The implications for agriculture and water resources include: reduction in weight and increased deaths of livestock, food shortages, and soil depletion, the existence of few rivers and streams, and the lowering of the water table. The study recommends the adoption of better herds management practices to include: the reduction in herd numbers, strategic weaning of calves, herd segregation, and parasite control. The establishment and improvement of early warning systems, analysis of observed climatic data, the establishment of Drought and Flood Research Centers in all the universities of the zone among others were the mitigating measures recommended.

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May 16, 2014