Authors: Salako F. K, Adejuyigbe C. O., Dada P. O., Oriak O. C., Martins O. and Adedire M. O.
Abstract
In Abeokuta, southwestern Nigeria, soil erosion and gravel/stone mining operations are processes through which accelerated loss of topsoil from prime agricultural lands occurs.
Thus, this study was conducted in the University of Agriculture, Abeokuta, Nigeria in 2003 to investigate stability after topsoil removal and nutrient amendment on 2 slope positions under maize cultivation. There were 3 replications for the factors which were 2 levels of slope position (lower and upper slopes), 3 levels of soil amendments (none, 60 kg N ha-1 as NPK + Urea, 10 t ha-1 poultry manure). Dispersion ratio and proportion of water stable aggregates > 4mm were measured Dispersion ratio was significantly different due to topsoil removal to 15 and 24cm depth at lower slope position with means ranging from 0.34 (lower slope x 0 cm topsoil removal) to 0.64 (lower slope x 15 cm topsoil removal). There were no significant differences for means of 0.35-0.42 observed for upslope position. After maize cultivation, dispersion ratio for upper slope x 0 cm topsoil removal.