Risk assessment and driving factors of trace metal(loid)s in soils of China

Recently, with the rapid development of China's economy, the pollution of trace metal(loid)s (TMs) in soils has become increasingly severe and attracted widespread attention. Based on 1,402 published papers from 2000 to 2021, this study aimed to analyze the pollution intensity, ecological risk and driving factors for eight TMs (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) in Chinese soils. Results showed that the average concentrations of eight TMs in Chinese soils all exceeded background values, and the pollution of Cd and Hg was the most serious. Based on Principal component analysis of pollution intensity and ecological risk, the priority control TMs were identified for the heavily polluted provinces. The results of Geo-detector model suggested that Urban development factors contributed most to the TM accumulation in Chinese soils. Further, spatial analysis using bivariate Moran's I indicated that industrial activities contributed most to soil TM accumulation in the middle and lower reaches of the Yangtze River, while soil TM pollution in the southwest and northwest provinces was mainly caused by mining and metal smelting. This study investigated the relationship between soil TM pollution and anthropo-genic activities, thus providing a scientific basis for controlling soil TM pollution at a large-scale level.

Automated summary

The pollution of trace metal(loid)s (TMs) in Chinese soils has become increasingly severe and attracted widespread attention with the rapid development of China's economy. This study analyzed the pollution intensity, ecological risk, and driving factors for eight TMs in Chinese soils based on a review of 1,402 published papers from 2000 to 2021. The results showed that the concentrations of all eight TMs in Chinese soils exceeded background values, with Cd and Hg being the most serious. The study identified priority control TMs for heavily polluted provinces and found that urban development factors contributed the most to TM accumulation in Chinese soils. The findings provide a scientific basis for controlling soil TM pollution at a large-scale level.