Spatio-temporal patterns and source identification of surface water pollution in Bohai Bay, China from 1995 to 2005 Available to Purchase

Several multivariate statistical methods were comprehensively used to interpret the temporal, spatial patterns and source identification of surface water pollution in Bohai Bay with the large and complex data. Twelve variables water quality indices were surveyed at 12 sites three times a year (May, August, and October) from 1995 to 2005. Cluster analysis (CA) grouped the eleven years into two clusters, Cluster A (1995 to 2001 except 1998) and cluster B (2002 to 2005 and 1998), and spatial CA divided the entire area into three groups. The results of discriminant analysis showed that the temporal CA and spatial CA were effective with 90% and 83.3% correct assignments, respectively. In cluster A, the pollution sources mainly were nutrient factor from non-point source and Hg pollution, oil and organic pollutions were relatively light. In Cluster B, the organic pollution became the mainly pollution source, and the nutrient pollution was still serious problem. In the results of spatial analysis, the group 1 was mainly affected by anthropogenic pollution, the group 3 was seriously affected by oil spill pollution and nutrients pollution, and the group 2 reflected relatively strong water self-purification ability.