SOURCE:

Faculty: Physical Sciences
Department: Pure And Industrial Chemistry

CONTRIBUTORS:

Okoye, O. N. N.
Eboatu, A.N.
Onwukeme, V.I.

ABSTRACT:

Soil erosion is the removal/movement of soil particles from one area to another; and one method of preventing these soil particles from eroding is by chemical stabilization (which involves altering the properties of the soil particles by adding cement, lime or any other cementing material). The aim of this study is to investigate the chemical stabilization of some soils of gully erosion-prone areas of Anambra State. Seven soil samples were collected from seven different locations of Anambra State. Two of the soil samples were non-erosion prone, while five were erosion prone. Physico-chemical analyses of these soil samples were conducted using different experimental techniques. The elemental components of the soil samples were analysed using AAS (Atomic Absorption Spectrophotometer). Results obtained from the non-erosive soils were used as control, and compare with the results from the erosive soils. From the results, the values of the cations (ppm), anions (ppm) and percentage clay were relatively higher in non-erosive soils than the erosive soils. For the percentage sulphur, percentage organic carbon and organic matter, pH in water and chloride, percentage moisture content and porosity (g/mL) had values which varied interchangeably. For percentage sand, the erosive soils have higher percentage sand than in the non-erosive soils. The 10g and 15g of the five erosive soils were each stabilized with 2mL of the following chemicals: AlCl3, CaCl2, MgCl2, CaCO3 and Ca(OH)2. After that, a pocket penetrometer was used to test for the Unconfined Compressive Strength (UCS). The results for the use of AlCl3 salt solution on 10g and 15g of Nanka, Oko, Oba, Nnewi and Oraukwu erosive soils are: 5.00, 5.00, 5.00, 4.00, 4.60kg/cm2 and 5.00, 5.00, 5.00, 5.00, 5.00kg/cm2, respectively. The results for the use of MgCl2 salt solution on 10g and 15g of Nanka, Oko, Oba, Nnewi and Oraukwu erosive soils are: 5.00, 2.60, 3.80, 2.50, 5.00kg/cm2 and 2.24, 5.00, 5.00, 3.30, 5.00kg/cm2, respectively. The results for the use of CaCl2 on 10g and 15g of Nanka, Oko, Oba, Nnewi and Oraukwu erosive soils are: 5.00, 3.00, 5.00, 5.00, 4.40kg/cm2 and 5.00, 5.00, 5.00, 5.00, 5.00kg/cm2, respectively. The results for the use of Ca(OH)2 on 10g and 15g of Nanka, Oko, Oba, Nnewi and Oraukwu erosive soils are: 1.55, 1.65, 1.30, 1.26, 0.80kg/cm2 and 0.60, 0.60, 2.52, 1.10, 0.15kg/cm2, respectively. The results for the use of CaCO3 on 10g and 15g of Nanka, Oko, Oba, Nnewi and Oraukwu erosive soils are: 1.10, 1.74, 1.70, 1.24, 1.45kg/cm2 and 1.14, 2.26, 3.65, 0.90, 3.74kg/cm2, respectively. Statistical analysis, such as: Kruskal Wallis Test, Mean Test and Wilcoxon Signed Rank Test were used to analyse the data. From the overall results, the increase in the rate of stabilization of the following salts as it relates to the use of different soil-sample masses are as follows: AlCl3> CaCl2> MgCl2> CaCO3> Ca(OH)2. This then means that the menace of soil erosion in Anambra State can be curbed by the use of these chemical solutions, which when administered in their right proportions, will go a long way in solving the problem of gully erosion in the State.