JACEN  Vol.4 No.4 , November 2015
Levels of Heavy Metals in the Soil: Effects of Season, Agronomic Practice and Soil Geology
Abstract: Heavy metals status of agricultural soils should be monitored in order to prevent soil-plant pollution. This study evaluates the effect of season, agronomic practice and soil mineral composition on the levels of some heavy metals (Pb, Mn, Ni, Fe, and Zn) in the arable and oil palm soils of three Farm Settlements in Ogun-State Southwest, Nigeria. Soil samples were collected in two consecutive seasons between 2010 and 2012 and digestion was carried out using Standard Wet Acid Digestion method. Total heavy metals in the digest were determined using Flame Atomic Absorption Spectrophotometer (FAAS). The total levels of heavy metals (in mg/kg) found in the sampled soils were as follows: in the rainy season Mn (28.4 - 34.2), Fe (1599.7 - 2013.2), Pb (11.0 - 16.9), Zn (100.5 - 112.9) and Ni (11.3 - 13.8) and in the dry season Mn (32.1 - 40.1), Fe (1701.4 - 2455.5), Pb (13.0 - 18.7), Zn (105.7 - 110.4) and Ni (15.5 - 16.3). Levels of the heavy metals found in the sampled soils were significantly lower (p < 0.05) than their permissible levels in agricultural soils. Although the levels of heavy metals determined in dry season were higher than those of the rainy season, the only seasonal difference was that of Fe in Sawonjo soil significant at p = 0.05. The level of heavy metals in oil palm soils was significantly higher than the level in arable soils (p < 0.05). At present, pollution level of heavy metals in the sampled soils is low and poses no environmental risk, yet, they have to be regularly monitored before they bio-accumulate into toxic. Government should therefore set up soil monitoring agency and provide irrigation facilities to encourage dry season farming.
Cite this paper: Osobamiro, M. and Adewuyi, G. (2015) Levels of Heavy Metals in the Soil: Effects of Season, Agronomic Practice and Soil Geology. Journal of Agricultural Chemistry and Environment, 4, 109-117. doi: 10.4236/jacen.2015.44012.

[1]   Micó, C., Recatalá, L., Peris, M. and Sánchez, J. (2006) Assessing Heavy Metal Sources in Agricultural Soils of a European Mediterranean Area by Multivariate Analysis. Chemosphere, 65, 863-872.

[2]   Tuzen, M. (2003) Determination of Heavy Metals in Fish Samples of the Middame Lakes Black Sea (Turkey) by Graphite Furnace Atomic Absorption Spectophotometry. Food Chemistry, 80, 119-123.

[3]   Adriano, D.C. (2001) Trace Elements in Terrestrial Environments: Biogeochemistry, Bioavailability and Risks of Metals. 2nd Edition, Springer, New York, 860.

[4]   Kubilay, N., Nickovic, S., Moulin, C. and Dulac, F. (2000) An Illustration of the Transport and Deposition of Mineral Dust onto the Eastern Mediterranean. Atmospheric Environment, 34, 1293-1303.

[5]   Oyekunle, J.A.O., Ogunfowokan, A.O., Torto, N. and Akanni, M.S. (2011) Levels of Heavy Metals in Agricultural Soils of Oke-Osun Farm Settlement Osogbo, Nigeria. Journal of International Environmental Application & Science, 6, 483-496.

[6]   Gbadegesin, S.A. (1992) Soils. In: Onakomaya, S.O., Oyesiku, K. and Jegede, J., Eds., Ogun State in Maps, Res. Charles Publication, Ibadan, 207.

[7]   Fifield, F.W. and Kealey, D. (1990) Principles and Practice of Analytical Chemistry. 3rd Edition, Chapman and Hall, Blackie Academic and Professional, London, 469-490.

[8]   Walkley, A. and Black, I.A. (1934) An Examination of Degtjareff Method for Determining Soil Organic Matter and a Proposed Modification of the Chromic Acid Titration Method. Soil Science, 37, 29-38.

[9]   Soil Survey Laboratory Staff (1992) Soil Survey Laboratory Methods Manual. Soil Survey Investigations Report No. 42, USDA-SCS, Washington DC.

[10]   Bouyoucos, G.J. (1962) Hydrometer Method Improved for Making Particle Size Analysis of Soils. Agronomy Journal, 53, 464-465.

[11]   Barman, S.C., Sahu, R.K., Bhargava, S.K. and Chatterjee, C. (2000) Distribution of Heavy Metals in Wheat, Mustard and Weed Grown in Fields Irrigated with Industrial Effluents. Bulletin of Environmental Contamination and Toxicology, 64, 489-496.

[12]   Twyman, R.M. (2005) Sample Dissolution for Elemental Analysis: Wet Digestion. In: Worsfold, P., Townshend, A. and Poole, C., Eds., Encyclopedia of Analytical Science, 2nd Edition, Volume 8, Elsevier Science, London, 146- 153.

[13]   Sylvia, D.M., Fuhmann, P.G., Hartel, P.G. and Zuberer, D.A., Eds. (1998) Principles and Application of Soil Microbiology. Prentice Hall, Upper Saddle River.

[14]   Keepax, R.E., Moyes, L.N. and Livens, F.R. (2011) Speciation of Heavy Metals and Radioisotopes. In: Aleksandar, S., Ed., Environmental and Ecological Chemistry Volume II, Encyclopedia of Life Support Systems (EOLSS), 165-199.

[15]   Esu, I.E. (1999) Fundamentals of Pedology. Stirling-Horden Publishers (Nig.) Ltd., Ibadan, 136.

[16]   FAO, Food and Agricultural Organization (1990) Guidelines for Soil Profile Description. 3rd Edition, FAO, Rome, 70.

[17]   Teutsch, N., Erel, Y., Halicz, L. and Chadwick, O.A. (1999) The Influence of Rainfall on Metal Concentration and Behavior in the Soil. Geochimica et Cosmochimica Acta, 63, 3499-3511.

[18]   Hartemink, A.E. (2003) Soil Fertility Decline in the Tropics—With Case Studies on Plantations. ISRIC-CABI Publishing, Wallingford.

[19]   Barcelo, J. and Poschenrieder, C. (2004) Structural and Ultra Structural Changes in Heavy Metal Exposed Plants. In: Prasad, M.N.V., Ed., Heavy Metal Stress in Plants, 3rd Edition, Springer, Berlin, 223-248.

[20]   Dimou, M., Paunescu, A., Aivalakis, G., Flemetakis, E. and Katinakis, P. (2009) Co-Localization of Carbonic Anhydrase and Phosphoenol-Pyruvate Carboxylase and Localization of Pyruvate Kinase in Roots and Hypocotyls of Etiolated Glycine max Seedlings. International Journal of Molecular Sciences, 10, 2896-2910.

[21]   Welch, R.M. and Cary, E.E. (1975) Concentration of Chromium, Nickel and Vanadium in Plant Materials. Journal of Agricultural and Food Chemistry, 23, 479-482.

[22]   Miller, G.S., Begonia, G.B., Begonia, M.F.T. and Ntoni, J. (2008) Bioavailability and Uptake of Lead by Coffee Weed (Sesbania exaltata raf.). International Journal of Environmental Research and Public Health, 5, 436-440.

[23]   Raymond, A.W. and Okieimen, F.E. (2011) Heavy Metals in Contaminated Soils: A Review of Sources, Chemistry, Risks and Best Available Strategies for Remediation International Scholarly Research Network Ecology, Tolerance in Plants. Biochimie, 88, 1707-1719.

[24]   US Environmental Protection Agency (1997) Test Methods of Evaluation for Solid Waste. USEPA S/W 846 UEPA, Washington DC.

[25]   Miller, J.N. and Miller, J.C. (2000) Statistics and Chemometrics for Analytical Chemistry. 4th Edition, Pearson Education Limited, Essex, 271.

[26]   Olutona, G.O., Olapeju, G.A. and Emmanuel, A.A. (2012) A Study of Chemical Speciation of Metals in Aquatic Bottom Sediment of Aiba Reservoir, Iwo, Nigeria. African Journal of Environmental Science and Technology, 6, 312-321.