Delineating Stations along the Coastline of Delta State, Nigeria into Pollution Categories: Multivariate Approach

Abstract

Aquatic ecosystems disturbance globally are increasing at alarming rate and it has debilitating effects on the ecological balance of the systems. The disturbances experienced by aquatic systems arise mainly from human influences. In this present study, we delineated six stations into pollution categories using multivariate approach (principal component analysis; PCA). The six stations selected were; SW 1- sea water (Benin River mouth/sea), SW2- Benin River (Benin River mouth/sea), SW3- sea water (Escravos River mouth/sea), SW4-River mouth (Escravos River mouth/sea), SW5- sea water (Forcados River mouth/sea) and SW6-River mouth (Forcados River mouth/sea). The PCA we constructed to visualize the relationship between the sampled stations and selected physico-chemical parameters showed that the first PCA component had a variance of 53.29% with an eigenvalue of 6.93 while the second PCA component explained 38.10% with an eigen value of 4.95. SW1 and SW2 were negatively correlated with DO, THC and conductivity, and nitrate, COD, TSS and temperature were negatively correlated with SW5 and SW6. Phosphate, salinity and turbidity were positively correlated with SW3 and SW4. Sulphate, pH and BOD were not associated with any of the stations sampled. Of the six stations we delineated, four were categorized as heavily polluted and they include; SW1, SW2, SW5 and SW6, while SW3 was moderately polluted and SW4 was fairly polluted. This showed that the selected stations within the coastlines of Delta State, Nigeria are heavily impacted by human influences.