Changes In Soil Properties Under Alley Cropping System Of Three Leguminous Crops

Abstract

A study to evaluate the changes in soil properties, under existing alley cropping system with three leguminous crops (Leucaena leucocephala, Gliricidia sepium, and Cajanus cajan) was conducted in the experimental farm of the Faculty of Agriculture and Natural Resources Management, Ebonyi State University, Abakaliki between 2003-2005. The study was established in a randomized complete block design with five treatments consisting of 10 t ha^-1 each of L. leucocephala, G. sepium and C. cajan prunings, 300kg ha^-1 of 20:10:10 and a control with no amendments. The study was replicated four times. Soil pH increased from pH 4.2 (strongly acid) in the pre- planting to pH 6.1 (slightly acid) in C. cajan alley plots. The organic matter increased from 1.01g kg ^-1 in the pre-planting to 5.98g kg^-1 in the C. cajan alley plots in 2005. Total N increased in all the alley plots with the highest N content of 2.31g kg^-1 in the G. sepium alley plots, which was 68% in 2003, 90% in 2004 and 95% in 2005 over the pre-planting. Available P and exchangeable Ca and Mg increased significantly (p<0.05) in the alley plots over the pre-planting. The ECEC increased in line with exchangeable bases. Total acidity and Al3+ saturation were very low in the alley plots.