ORIGIN AND CORRELATION OF VARIABLES IN SOME BOREHOLES OF BUI DIVISION IN THE NORTH WEST REGION OF CAMEROON

Abstract

Multivariate data with inherent complexity can be simplified and interpretation eased with application of the Principal Component Analysis (PCA), while retaining trends and patterns. Huge data is reduced to fewer dimensions, maintaining the intrinsic relation between the variables. Sample bottles were cleaned and rinsed with the water sample from the boreholes, and finally filled to the brim to avoid any atmospheric oxidation. The samples were taken immediately to the Laboratory for physico-chemical analysis. The Boreholes were BH1 (Oku subdivision), BH2 (Mbven subdivision), BH3 (Nkum subdivision), BH4 (Jakiri subdivision) and BH5 for Kumbo subdivision. The PCA had application of the Software Package for Social Sciences SPSS), that converted the complex variables obtained from the analysis, at different periods and sites into a correlation matrix. Pearson’s correlation matrix applied in this work, reduced the data in correlation circles that were a range of geometrical projections from higher to lower dimensions. There was no strong correlation between the different variables indicating that they function independently. Most of the correlation values lie between +/- 0.29 and 0.1 which indicated a low degree of correlation. Nonetheless, absence of correlation never existed between the correlated pairs as no value of zero was obtained. Sixty-six variables were correlated, with 31 having a positive correlation, whereas 35 were negative. Consequently, 46.96 % variables had positive correlation and 50.04% with a negative correlation. The positive correlation values indicated a common source with the variables evolving similarly. A negative correlation of -0.185897 was expressed between Ca2+ and HCO3- within the boreholes. A negative correlation of pH with EC (-0.032559) and other anions (NO3- ; -0.137635, Cl-; -0.091810, SO42- ; -0.111072) indicated a decrease in pH (acidification) which can be linked to an increase in the mineralization process that increase anions into the milieu. The pairs of exchangeable bases; Na+- Ca2+; (0.138758) Na+- K+, (0.412315) had positive correlations which indicated that; increasing or decreasing of the concentration of cations was probably a combination of anthropogenic inputs and other processes governed by chemical reactions. An exception was with Na+- Mg2+ pair that gave an anomaly with a negative correlation (-0.090762). The anomaly was ignored because the low correlation coefficient was insignificant. The findings from this work enabled the origins of ions in the boreholes to be identified and related.