Water quality assessment of Alibaug mangrove forest using multivariate statistical technique, Maharashtra, India

Abstract

Physicochemical properties of surface water from Alibaug mangrove forest and Akshi coastal area were examined using multivariate statistical techniques viz. cluster analysis and factor analysis during October to December 2010.  Water quality assessment was done by estimating pH, temperature, EC, TDS, DO, COD, salinity, hardness, SAR, TPH, TOG, Na⁺, Ca²⁺, Mg²⁺,Cl^-, NO^3- and PO₄^3-. Water in general showed high values of Hardness, salinity, TDS, EC, COD, TOG, calcium, magnesium, chloride, nitrate and phosphate. Dominant cation and anion were Na+ and Cl^- respectively. Cluster analysis grouped sampling sites into three clusters of similar hydrochemical features and classified mangrove forest to low, moderate and high pollution zones. Factor analysis revealed that the most significant parameters contributing to water quality variation are: EC, Na⁺, PO₄^3-, SAR, Ca²⁺, temperature, salinity and Cl^-. According to factor analysis different natural and anthropogenic sources affect the water quality of study area viz. weathering and seasonal variation, agriculture runoff, domestic and industrial sewage disposal and oil from spill.