Impact of Livestock Manures on Soil Organic Matter and Adsorption in Cassava Cultivation (Manihot esculenta, Crantz)

Abstract

This study examined the A and B horizons of deep, developed and moderately unsaturated sandy ferrallitic soils 
amended with cattle and poultry manures under cassava (Manihot esculenta Crantz) cultivation. Therefore, a plot 
experiment was carried out by using a randomized complete blocks design in 4 replications and fields treatments 
which included unfertilized (control) and one dose (10 t/ha) of both manures. The study of the different fractions of 
animal manures showed that the poultry had the greatest content of C (organic carbon), N (nitrogen), P 
(phosphorus), K (potassium), Ca (calcium) and C:N ratio (p < 0.01). However, the value of Mg (magnesium) in the 
studied manures was not significantly different (p < 0.01). The manure treatment significantly increased the soil 
organic matter contents from 0.46 to 2.8 and 1.1% respectively with poultry and cattle manures (p < 0.01). Organic 
fertilizer significantly increased the cation exchange capacity from 1.7 to 12.75 and 3.8 me:100 g and the bases 
saturation content from 47 to 80 and to 76% respectively with the poultry and cattle manures (p < 0.01). The organic 
fertilizer showed significant effect on earthworms populations Hyperiodrilus africanus (Oligochaeta, Eudrilidae) in 
the soil, with 128 and 85% respectively about the poultry and cattle manures compared to the control (p < 0.01).