Application of Erodibility Nomograph in the Assessment of Soil Erosion
in Two Different Agro-ecological Zones
Abstract
This study highlights application of erodibility nomograph to assess
soil erosion in central and northern agro-ecological zones of Cross
River State, Nigeria. Seventeen composite soil samples were collected
from sites showing moderate to severe erosion problems to the depth of
0-30 cm with the use of soil auger by random sampling and analyzed using
standard laboratory procedures. Results showed that the particle size
analysis was coarse textured soils with high sand content giving
dominant textural classes of sandy loam in central and loamy sand
texture in northern agro-ecological zones. The soil separates were
predominantly silt content in central and medium sand in the northern
agro-ecological zones with mean values of 29.5 % and 26.3 %. The
erodibility using nomograph showed low to medium (0.10 – 0.19 Mg ha-1
MJ mm-1) in the central and medium (0.20 – 0.29 Mg ha-1 MJ mm-1) in the
northern agro-ecological zones with high CV (%) of 52.4 % in the
central and 118.2 % in the northern agro-ecological zones suggesting
erodible soils. Soil conservation measures such as contouring, mulching
and cover cropping should be adopted to address and combat soil erosion
to avoid serious soil erodibility.