Spatial Distribution And Ecological Risk Assessment Of Heavy Metals In A Manganese (Mn) Mining Area

Mining plays an important role in national economic and social development,but mining wasteland often brings serious environmental problems and is an important source of soil heavy metal pollution.Metal trace sources were identified;their topsoil locations were mapped out,as well as potential ecological impacts,in the land surrounding a typical manganese-contaminated site located in Hunan Province,China.The amounts of Mn,Cu,Pb,Zn,Cd,and Cr in the topsoil of the research region were determined.Twenty hectares of bare soil,grassland,and woodland were sampled for 23 soil samples with different depths.Soil characteristics and heavy metal concentrations were measured.Heavy metal distribution maps were created using the Kriging interpolation method.Heavy metal pollution across the entire region was quantified using geographical accumulation indexes.Using GIS,the data shows that trace metals in topsoil are enriched mostly around mining and smelting operations.Soil samples from this area were found to contain high levels of contaminant elements such as chromium(Cr),manganese(Mn),copper(Cu),zinc(Zn),and lead(Pb).Heavy metal concentrations in different places were also extremely variable.On the other hand,the lowest amount of Mn was just 50.1 mg/kg while the maximum was 55569 mg/kg,a 121-fold increase above the standard.As demonstrated by these results,X-ray fluorescence spectroscopy(XRF)was found to be a reliable and rapid alternative to inductively coupled plasma-mass spectrometry(ICP-OES)for the determination of Mn and other metals in soils.Moreover,the total organic carbon in soils was rising with increasing ecological succession stages.INI and PERI were used to quantify metal contamination in the research area’s prospective ecological risk.Studies have shown that the INI index of heavy metals in most regions of the soils is greater than 1,and the PERI index in most regions is greater than 150,which is above the moderate ecological risk,causing serious risks to the local ecological.7 Figures,4 Tables,and 109 References...