Objective  The problem of soil health in urban green space has been widely concerned by people. The purpose of this study is to grasp the heavy metal pollution of green space soil in Huangshi City, Hubei Province, and to provide technical support for the ecological construction and transformation development of such mining and metallurgical cities.

  Method  According to the multi-point mixing method, sampling points were selected for road green space layout in Huangshi City. A total of 48 soil samples were collected to determine the contents of various metal elements. The geo-accumulation index method, the potential ecological hazard index method and multivariate statistical analysis were used to evaluate the pollution. ArcGis10.2 was used to visualize the distribution of heavy metals, and the correlation analysis and principal component analysis were used to analyze the source of each heavy metal element.

  Result  The results showed that the average contents of Pb, Zn, Cr, As, Cd and Cu were 200.12, 424.88, 109.96, 56.74, 4.02 and 376.81 mg kg⁻¹. They exceed the background value in Hubei Province by 7.49, 5.08, 1.28, 4.61, 23.67 and 12.27 times, respectively. Except for Cr, the percentages of points exceeding the background value to the total were: Cu 100%, Pb 97.92%, Zn 97.92%, As 93.75% and Cd 100%. The evaluation of the geo-accumulative index showed that 53.06%-87.08% samples are at a moderate to severe pollution level, and the comprehensive potential ecological hazard index of 89.58% samples was greater than 150.

  Conclusion  The distribution of Cr is relatively uniform, but there are still high value areas, which are located near a large steel smelting enterprise in Xisai Mountains. The distributions of Pb, Zn, As, Cu and Cd contents are quite different. High-value areas are all located in Huangshi Port area, and extremely high-value points are located near a large non-ferrous metal smelting plant in Xialu District. The geo-accumulation index indicates that the pollution degree of the six heavy metals is: Cd > Pb > Cu > Zn > As > Cr; the potential ecological hazard index is: Cd > Cu > As > Pb > Zn > Cr. Cd is the most important pollution element in the area. Multivariate statistical analysis shows that Pb, Zn, As, Cd, and Cu are anthropogenic sources and are related to non-ferrous metal smelting and transportation. Cr mainly comes from weathering of rocks and soil parent materials.