ABSTRACT

An incubation experiment was conducted in the Soil Science laboratory, Michael Okpara University of Agriculture, Umudike to evaluate the effect of cow bone ash on soil acidity in an acid Ultisol of south eastern Nigeria. The incubation study determined the effects of bone ash on soil pH in water and exchangeable acidity. The treatment used was cow bone ash applied at five levels (0, 2, 4, 6 and 8 tons per hectare), and was replicated three times in a completely randomized design. The effects of the treatment on pH and exchangeable acidity were measured and all data were subjected to analysis of variance (ANOVA) and the difference between the treatments was tested using the Genstat package. The results obtained showed that at 14th day of incubation, 8 tonnes per hectare of bone ash siiflcantIyincreased the soil pH from 5.63 to 6.63, similarly at 28th and 4211 day of incubation respectively was increased from 7.02 to 7.18. At the 56th day of incubation, 4 tonnes and 8 tonnes per hectare respectively, of bone ash significantly increased the soil pH from 6.86 to 7.62 and 7.18 to 7.51 respectively. The results obtained, showed that cow bone ash significantlyreduced exchangeable acidity when applied at 8 tonnes per hectare from 1.25 to 0.80 (from the 1st to the 56th day). It also revealed that bone ash significantlyreduced exchangeable acidity when applied at 4 tonnes and 8 tonnes per hectare from 1.33 to 0.80 and 1.13 to 0.80 respectively at 56th day of incubation. In the incubation study, Cow Bone Ash at 8tons/ha gave the highest soil pH and least value of soil exchangeable acidity. The rate of 8 tons/ha produced the best soil pH value and least value of soil exchangeable acidity. This study shows that cow bone ash was able to reduce soil acidity which could lead to the solubility of soil nutrients and consequently improve the yield of plants grown on such soils.