Multivariate analysis of contaminants in paddy soils polluted by Dabaoshan sulfur-polymetallic mines in the north of Guangdong

Soil samples were collected to investigate contamination degree in paddy soils polluted by Dabaoshan sulfur-polymetallic mines in the north of Guangdong Province. Principal component analysis (PCA) was employed to characterize the relationship among environmental variables and determine spatial distribution of contaminants. The results demonstrated that long-term wastewater irrigation resulted in depositing of wastes of limonites, copper pyrites and Pb-Zn mines in studied paddy soils, which induced soil acidification and accumulation of sulfur, copper, lead and cadmium. These contaminants were significantly correlated with iron and calcium, while were poorly correlated with manganese and chromium. Moreover, elevated contamination trend was revealed in the paddy soils with approaching the contamination sources. PCA was suggested to be an efficient multivariate analysis method of multiple soil contamination.