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Use of models in assessing
the impact of cropping system, land types and suitability on
land degradation in Southwestern Nigeria
Aruleba, J. Olusegun* and Ajayi, A. Samuel
Department of Crop, Soil and Environment Sciences University
of Ado-Ekiti, Ekiti State, Nigeria.
*Corresponding author. E-mail:
arulebaunad@yahoo.com.
Accepted 14 September, 2010 |
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Two sites (Apomu and Alabata) measuring 10 ha and
representing rainforest and savannah agro-ecological zones,
respectively in South Western Nigeria were chosen to
evaluate the influences of cropping system, suitability and
land types on the degree of land degradation. Multiple
linear step-wise forward elimination regression was use to
measure the interrelationships of the land parameters
measured. The result using the model Y = 0.99 – 0.21CS +
0.10LT + 0.36S showed that for Apomu, the cropping system
contributed 30% to the degradation as indicated by bulk
density. Organic matter, conductivity and land suitability
contributed more than 15% in terms of bulk density and
permeability while land type contributed 17.5 and 2% of the
degradation due to permeability and organic matter
respectively. At Alabata, the model that best describes the
relationships is Y = 0.17 + 0.09CS + 0.23LT + 0.31S.
Cropping system contributed 10 - 12% degradation while land
type contributed between 6.5 – 17.3% due to organic matter
content, ESP, exchangeable K and bulk density. Land
degradation models were also developed for each nutrient
based on the cropping system, suitability and topographic
land types. Appropriate cropping systems such as alley
cropping, organic farming, contour farming, and rotational
cropping etc. are recommended for the defined soil / land
types to minimise land degradation in the study area.
Key words:
Land degradation, cropping system, land type, model and
suitability. |
