An Assessment of Rainfall Erosivity in Parts of Eastern Nigeria: A Case Study of Owerri and Enugu

  • I. Balogun
  • O. Adegun
  • O. Adeaga
Keywords: Rainfall, Rainfall Erosivity, Erosion, Modified Fournier Index, Decade

Abstract

Information on the aggressiveness and erosive power of rains received within eastern Nigeria is necessary for the proper management of soil erosion hazard within the region. In recognition of the role of rainfall as an inceptor and facilitator of soil erosion, rainfall erosivity of Owerri and Enugu was estimated using the Modified Fournier Index (MFI). The results showed that the rains received between 1974 and 2011 were highly erosive, with the annual rainfall erosivity computed of the study period being consistently greater than 160 mm.

The degree of relationship between annual rainfall and annual rainfall erosivity for the study period which was established using the Karl Pearson’s Coefficient of Correlation revealed a moderate (r = 0.609) and a high (r = 0.795) degree of positive relationship for Owerri and Enugu, respectively. In the light of the results obtained, an improved understanding of the climatic and hydrologic regime of the area is advocated in order to evolve better soil protection and management strategies.

References

Anugulo-Martinez., M and Begueria, S. (2003). Estimating rainfall erosivity from
precipitation records: A comparison among methods using data from Ebro basin NE (Spain). Journal of Hydrology, 379(1-2), 111-121.
Lujan, D.L., and Gabriels, D. (2005). Assessing the rainfall erosivity and rain distribution in
Different agro-climatological zones in Venezuela. Sociedade and Natureza, Uderlandia, Special Issue, 16-29, May, 2005, 16-29.
Monanu, P.C. (1975). Rainfall. In : Nigeria in maps: Eastern States, Ofomata, G.E.K. (Ed).
Ethiope Publishing House, Benin City, Nigeria
Ofomata G.E.K. (1975a). Soil. In : Nigeria in maps: Eastern States, Ofomata, G.E.K.
(Ed). Ethiope Publishing House, Benin City, Nigeria.
Ofomata G.E.K. (1975b). Soil Erosion. In : Nigeria in maps: Eastern States, Ofomata, G.E.K.
(Ed). Ethiope Publishing House, Benin City, Nigeria .
El-Swaify, S,A, Dangler, E.W and Amstrong, C.L (1982). Soil Erosion by Water in
the Tropics. College of Tropical Agriculture and Human Resources, University of Hawaii
Salako, F.K. (2000). Susceptibility of coarse textured soils to erosion by water in the tropics.
Lecture given at College on Soil Physics, Triste, 3-21 March, 2003.
World Meteorological Organisation (2005).
Stanga, I.C. (2011). Climate aggressiveness and rainfall erosivity. Riscuri Şi Catastrofe,
N.R. X, 9 (NR.2/2011), 21-32.
World Meteorological Organisation (2005). Climate and Land Degradation. WMO-
No.989.
Issue
Section
Articles