E3 Journal of Agricultural Research and Development
E3 Journal of Agricultural Research and Development Vol. 2 (2) pp. 066-073, May 2012; © E3 Journals; ISSN 2276-9897
Effects of long term fertilizer use on trace metal levels of soils in a farm settlementS.O. Ajayi1 * , B.O. Odesanya1 , A.O. Avwioroko2 , G.S. Adebambo2 , B. Okafor3
1 College of Pure and Applied Sciences, Caleb University, Imota. Lagos State
2 Chemistry Department, University of Ibadan, Oyo State.
3 National Institute for Horticultural Research, Ibadan, Nigeria
*Corresponding Author E-mail: firstname.lastname@example.org.
Accepted 19 March 2012
Long term use of fertilizers for agricultural purposes has been an issue of concern to researchers. The presence of metals in some agricultural fertilizers raised fears that continued use could lead to accumulation of these metals to toxic levels in the soil. We investigated the effects of long term fertilizer use on the distribution of selected trace metals in soils at the National Institute for Horticultural research (NIHORT), Ibadan, Oyo state where extensive agricultural practices have taken place for over 33 years. Results indicate that the total metal concentration after prolonged fertilizer use is of the order Mn>Zn>Pb>Cu>Cd. Metal concentrations obtained from the fertilized sites of the plots studied were higher than that of the unfertilized site. However, testing at P < 0.05 indicate that there has not been significant accumulation of these metals due to prolonged fertilizer use. This indicates that the distribution of metals among the various metal fractions between fertilized/unfertilized sites have not changed significantly following the long-term use of fertilizers in the Institute(NIHORT). Recovery studies establish the accuracy of the results at 97% for copper and 84% for zinc in the carbonate fraction of typical fertilized and unfertilized soil samples.
Keywords: Trace metal concentration, fertilizers, agricultural practices[Download Article - PDF]