Global Advanced Research Journal of Agricultural Science (GARJAS) ISSN: 2315-5094
July 2018 Vol. 7(7): pp. 198-216
Copyright © 2018 Global Advanced Research Journals
Full Length Research Paper
Geostatistical modeling and agricultural perspectives of vertisol properties in the Benue Floodplain of North Cameroon
P. Azinwi Tamfuh 1, 2*, E. Djoufac Woumfo 3, F.O. Tabi1, M. Angue-Abossolo4 and D. Bitom1
1Department of Soil Science, Faculty of Agronomy and Agricultural Sciences, University of Dschang, P.O. Box 222 Dschang, Cameroon.
2Department of Mining and Mineral Engineering, National Higher Polytechnic Institute, University of Bamenda P.O. Box 39 Bambili, Cameroon
3Department of Inorganic chemistry, Faculty of Science, University of Yaoundé I, P.O. Box 812 Yaoundé, Cameroon.
4Department of Earth Sciences, Faculty of Science, University of Yaoundé I, P.O. Box: 812 Yaoundé, Cameroon.
*Corresponding Author's Email: crysle81@hotmail.com
Accepted 03 June, 2018
Abstract
Vertisols are dark coloured soils which are widespread in the tropical zone. They are renowned to be chemically very fertile soils. However, due to their difficult workability imposed by most of their physical chracteristics, they remain agriculturally underexploited. The aim of the present work was, firstly, to study the spatial distribution of the main physico-chemical properties of the Benue watershed vertisols by statistical and geostatistical methods, and secondly, to highlight the agricultural significance of the spatial structure of these properties. So, vertisol samples were collected in two grids demarcated in two plots, one under sorghum and the other one under natural savannah of gramineae. Fieldwork was followed by a battery of laboratory analyses. The data obtained was analysed statistically and geostatistically based on kriging. The results showed that most of the vertisol properties among the two studied plots did not vary significantly (P>.05) when viewed at the soil series scale. Furthermore, the principal component analysis (PCA) enabled to reduce fifteen initial studied variables to four principal components explaining more than 70% of the total variance. Geostatistically, most of the vertisol characteristics under sorghum were best-fitted by a “pure nugget effect” with cyclic periodicity in some cases, while those under savannah were mostly best-fitted by a linear model. Such “pure nugget effect” might imply that, although with a generally lower fertility level, the vertisols subjected to cultivation under sorghum remained very fertile with a better homogenisation of the fertility parameters, compared to fallow ones under natural savannah that instead showed “islands” of fertility portrayed by cyclic periodicity associated with vegetation tuffs. Contour maps obtained by kriging could have great potential for designing strategies for site-specific management.
Keywords: vertisols, spatial variability, agronomic value, Benue floodplain, North Cameroon.
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