[Mobilization of Heavy Metals in a Soil-Plant System and Risk Assessment in the Dabaoshan Mine Area, Guangdong Province, China].

This study analyzed heavy metal concentrations in mining/agricultural soil and plant samples from the Dabaoshan mining-impacted region, Guangdong Province, and evaluated the corresponding health risks. The results showed that most of the soil samples exhibited a pH<5, which, in some cases, facilitated the release of Cu, Pb, and Al from soil and hence affected the availability for plant uptake. Farmland in Shaxi town was found to be seriously polluted by Cd, whereas the mining area was seriously polluted by Cd, Pb, Cu, and As, which present potential ecological risks. Farmland in Xinjiang town was seriously polluted by Cu, As, and Cd, and also present ecological risks for this area. The concentrations of heavy metals (especially Al and Fe) in the eight plant species assessed were mostly higher than that in plants grown in non-contaminated soil. Only 10% of the bioconcentration factors and 18% of the translocation factors were higher than 1 in the aerial parts of plants, indicating that most heavy metals were concentrated in plant roots. Heavy metal concentrations in shoots of and were not high, and their accumulation from soil to plant was poor. These plants are excluder species and can be used for phyto-stabilization and management. Weeds like species in contaminated agricultural field showed a strong enrichment ability for Cd. Rice mainly accumulated As and Cd in the roots and belongs to root compartment plants.