Evaluation of Rainfall Erosivity Index for Abuja, Nigeria Using Lombardi Method

  • MO Isikwue
  • JO Ocheme
  • MI Aho
Keywords: Rainfall intensity, kinetic energy, Erosion, Erosivity, infiltration, runoff

Abstract

Rainfall erosivity index is one of the important factors influencing soil erosion. Erosivity index for Abuja, Nigeria was evaluated using the Lombadi method. Twelve (12) years rainfall data (2001 – 2012) used was obtained from Nigerian Meteorological Agency (NIMET) Abuja.  Daily kinetic energy – intensity interaction was computed using EI = 1.03Vd1.51. The results showed that the average annual rainfall erosivity index for the city for the period of study was 1131.86 MJmm/hr.  The correlation between annual erosivity index and average annual precipitation was expressed as Y = 8.2209X + 34.659. The coefficient of Determination R2 was 0.5011. During this period, the month of August (in all the years) had the highest erosivity index except for 2001, 2002, 2005 and 2008. The analysis of rainfall seasonal distribution showed that the most intensive erosion menace in the area can be expected in August, especially in the areas that are not protected by vegetation cover, which also depends on the climatic change. It is recommended that soil surfaces should not be left bare.

http://dx.doi.org/10.4314/njt.v34i1.7

Published
2014-12-29
Section
Building, Civil & Geotechical Engineering

Journal Identifiers


eISSN: 2467-8821
print ISSN: 0331-8443