Spatial distribution and pollution source assessment of different depth of soil heavy metals in the Wucaiwan coal field in Xinjiang East Junggar basin

The region of Wucaiwan open coal mine in East Junggar Basin in XinJiang was selected as study area.By measuring six heavy meatal elements which include Hg，As，Zn，Cu，Cr and Pb in soil，we use multivariate statistical analysis，unidirectional index，nemero pollution index，geoaccumulation index，the potential ecological risk index，special interpolation and dust analysis of heavy metal to analysis the pollution status and scope，spatial distribution characteristics，pollution source and evaluate the pollution degree of the soil heavy metal in the study area.The result indicates that，soil heavy metal contents of Hg，As and Cr were high than the Xinjiang background value 3.0，2.8，1.6 times respectively.A Strong positive correlation was found between Zn and Cu，and these two chemical elements were supposed to derived from soil parent materials.Hg was mainly influence by anthropogenic factor.As，Cu and Cr were derived from soil parent materials and human factor.Ecological risk assessment shows that Hg was in a high risk and other five heavy metal elements were in a low risk，the total potential ecological risk index was in a higher grade.The spatial distribution analysis of the soil heavy metal shows the high pollution area was assembled around the open pit coal mine area，roads and two industrial parks.The spatial distribution of the soil heavy metal was strongly influenced by coal mining，coal mine transportation，coal chemical industry and energy industry.