MULTIVARIATE ANALYSIS OF ABY LAGOON SEDIMENTS: IDENTIFICATION OF METAL CONTAMINATION SOURCES

This study aimed to identify probable sources of trace metal pollution in sediments of the Aby Lagoon (Etuessika sector - Assinie Canal) through multivariate statistical analyses. Conducted as a field based geochemical observational study, sediment samples were collected during the campaign of 7-8 October 2025 and analyzed for trace metals (As, Cd, Cr, Cu, Fe, Hg, Ni, Pb, Zn, Al). Principal Component Analysis (PCA) and Pearson correlations were applied to determine associations between elements and to distinguish lithogenic, anthropogenic, and historical sources of contamination. Results showed that three principal components explained the total variance: PC1 (61%) reflected lithogenic/diagenetic control dominated by Al, Cr, Cu, and As in opposition to Fe; PC2 (26.22%) revealed a recent anthropogenic signature characterized by Hg-Zn, typical of artisanal gold mining; and PC3 (12.78%) highlighted historical contamination, opposing Ni of lithogenic origin and Pb as a persistent pollutant linked to industrial discharges and former use of leaded fuels.