Comparison of the concentrations, sources, and distributions of heavy metal(loid)s in agricultural soils of two provinces in the Yangtze River Delta, China

Jiangsu and Zhejiang provinces, located in the Yangtze River Delta (YRD) core region, are the most economically developed regions in China, as well as the areas with serious soil pollution. The concentrations, sources, and distributions of heavy metal(loid)s in agricultural soils of the two provinces were studied; positive matrix factorization model (PMF) analysis and kriging interpolation were combined to compare the pollution characteristics of heavy metal(loid)s. The results showed that the degree of accumulation might be more serious in Zhejiang province than in Jiangsu province, especially in terms of Cd, Hg, and Pb. PMF results showed anthropogenic activities were the dominant factors affecting the concentrations of soil heavy metal(loid)s. The contributions of the three sources in Jiangsu province were 40.28% natural and traffic sources, 37.49% agricultural sources, and 22.22% industrial and coal combustion sources. The contributions of the three sources in Zhejiang province were 43.45% agricultural and industrial sources, 32.15% natural sources, and 24.40% industrial sources. The kriging interpolation results of the two provinces showed that the concentrations of As, Cr, and Ni were significantly higher in Jiangsu province than in Zhejiang province; the concentrations of Cu were similar in the two provinces, while other heavy metals had higher concentrations in Zhejiang province. These accumulations of heavy metal(loid)s in agricultural soil in both provinces cannot be ignored. This work will contribute to the development of effective policies aimed at protecting the soil environment from long-term accumulation of heavy metal(loid)s.