Analysis of Pollution Sources of Heavy Metal in Farmland Soils Based on Positive Matrix Factorization Model

Abstract

In this research, a total of 103 samples of surface farmland soil in Jiangjin district are collected by 1000m × 1000m grid method, and the content distribution characteristics of such heavy metals as Cd, Hg, Zn, Pb, Cu, as, Ni, Cr in the soil are analyzed. Positive Matrix Factorization (PMF) model is adopted to analyze the pollution sources and contribution rates of these eight heavy metals in the study. The results show that the contribution rate of atmospheric deposition source is 19.7%, that of industrial source is 27.0%, that of natural parent material source is 35.5% and that of agricultural source is 17.8%. It can be seen from the analytical results of PMF model that human factors (64.5%) such as industrial and agricultural production is the main pollution source of heavy metal in farmland soil.