Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China; National Engineering and Technology Research Center for Red Soil Improvement, Red Soil Ecological Experiment Station, Chinese Academy of Sciences, Yingtan, 335211, PR China.
Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, PR China; College of Resource and Environment, Anhui Science and Technology University, Fengyang, Anhui, 233100, PR China; National Engineering and Technology Research Center for Red Soil Improvement, Red Soil Ecological Experiment Station, Chinese Academy of Sciences, Yingtan, 335211, PR China.
J Hazard Mater. 2019 Jan 15;362:9-16. doi: 10.1016/j.jhazmat.2018.09.032. Epub 2018 Sep 12.
The objective of this study was to investigate the bioavailability of heavy metals from atmospheric deposition on the soil-pakchoi (Brassica chinensis L.) system near a smelter. Soil reciprocal translocation experiment was conducted with seven groups of pot culture (filled with soils of gradient levels of heavy metals) in three sites of gradient atmospheric heavy metal depositions. Results showed that the newly deposited heavy metals (Cu and Cd) were preferential retention in topsoil (0-4 cm) and presented as higher bioavailable fractions compared to those in original soils. Atmospheric depositions contributed to 20-85% of shoot Cu and Cd in high deposition site, which were likely resulted not only from the direct transfer of contaminants from atmosphere to foliar but also from the atmosphere-soil-root transfer. However, the 52-62% of Pb in shoot from atmospheric depositions was mainly resulted from foliar direct uptake. The increasing atmospheric heavy metal depositions significantly decreased the photosynthetic parameters of pakchoi. Additionally, the potential health risks associated with the consumption of pakchoi were elevated in high deposition site and the bioaccessibility values were observed up to 56-81%. This study will provide useful reference information for the newly deposited heavy metal dynamics in the surface environment.
本研究旨在探讨冶炼厂附近土壤-小白菜（Brassica chinensis L.）系统中大气沉降重金属的生物可给性。在梯度大气重金属沉降的三个地点，用七组盆载实验（用梯度重金属土壤填充）进行了土壤反向迁移实验。结果表明，新沉积的重金属（Cu 和 Cd）优先保留在表土（0-4cm）中，与原土壤相比，呈现出更高的生物可利用分数。在高沉降区，大气沉降对小白菜地上部 Cu 和 Cd 的贡献率为 20-85%，这不仅可能是由于污染物直接从大气转移到叶片，还可能是由于大气-土壤-根转移。然而，大气沉降中 Pb 的 52-62%主要来自叶片的直接吸收。大气中重金属沉降的增加显著降低了小白菜的光合参数。此外，高沉降区食用小白菜带来的潜在健康风险增加，生物可给性值高达 56-81%。本研究将为地表环境中重金属的新沉积动态提供有用的参考信息。
