| چکیده انگلیسی مقاله |
Multivariate statistical techniques, such as cluster analysis (CA), principal component analysis (PCA), factor analysis (FA), were applied for the evaluation of temporal/spatial variations and the interpretation of a large complex water quality data set of the Karoon river basin, generated during 13 years (1994-2006) monitoring of 13 parameters at 26 different sites. Hierarchical cluster analysis grouped 26 sampling sites into four clusters, i.e., relatively less polluted (LP), medium polluted (MP), highly polluted (HP) and extreme polluted (EP) sites, based on the similarity of water quality characteristics. PCA/FA, applied to the data sets of the three different groups (LP, MP and HP) obtained from CA, and Consequently effective variables reduction from PCA/FA in this case was found in VF1 and were included %Na, S.A.R, Na, Cl, Ec and T.D.S. VF1 explaining 35.89, 45.18 and 36.43% of the total variance in water quality data sets of LP areas respectively for the summer, autumn season and MP areas, for the spring season and also VF1 explaining 41.77, 44.97, 52.24, 35.14, 26.87, 38.46 and 48.38% of the total variance in water quality data sets of HP areas for the spring season and MP and HP areas, respectively for the summer, autumn and winter season. |