Related Experiment Video
Updated: Nov 27, 2025
Two-Dimensional Visualization and Quantification of Labile, Inorganic Plant Nutrients and Contaminants in Soil
Published on: September 1, 2020
Trace element contamination in urban topsoil in China during 2000-2009 and 2010-2019: Pollution assessment and
Zhongping Yang1, Xuyong Li1, Yao Wang1
1School of Civil Engineering, Chongqing University, Chongqing 400045, China; Key Laboratory of New Technology for Construction of Cities in Mountain Area (Chongqing University), Ministry of Education, Chongqing 400045, China; National Joint Engineering Research Center for Prevention and Control of Environmental Geological Hazards in the TGR Area Chongqing University, Chongqing 400045, China.
Abstract:
The Chinese government has launched a critical battle against soil pollution in recent years to establish an effective pollution prevention and control framework. This study sought to investigate the long-term pollution status of potentially toxic trace elements in urban topsoil nationwide, and to further investigate the effectiveness of pollution control over the past decade. The concentrations of 8 elements (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) in urban topsoil in China between 2000-2009 and 2010-2019 were separately collected for comparative analysis. Individual and comprehensive pollution levels of the elements were evaluated at the city, provincial, regional, and national scales, and further spatially mapped using GIS. Combined with PCA, the main factors influencing these elements in soil nationwide were identified. The results revealed a severe situation in terms of potentially toxic trace element accumulation in urban topsoil, where the NNIPIs surpassed 3 in both periods. The elements As, Cd, and Hg were closely associated with industrial activity and coal burning. Hg and, in particular, Cd pollution (NPI > 3) were found to be severe in most of the cities studied. For the elements As, Cu, Pb, and Zn, pollution ranged from slight to moderate (1.0 < NPI ≤ 3.0), and Cu, Pb, and Zn were related to a significant degree with vehicle use. Soil Cr and Ni were mainly controlled by parent materials of lithogenic origin, and slight pollution was identified (1.0 < NPI ≤ 2.0). Pollution patterns showed different characteristics across the regions, and those of the same region and the nation hardly changed over time. Mercury pollution was dominant in the northern regions (NW, MYeR, NE, and NC), while Cd pollution was more severe for the south (EC, MYaR, SC, and SW). Notably, the country's comprehensive pollution level was stable across the two periods, with momentum towards improvement observed over the past decade.
