Vertical and Lateral Redistribution of POPs in Soils Developed along a Hydrological Gradient

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• 作者：Magnus Bergknut ; Karin Wiberg ; Jonatan Klaminder
• 刊名：Environmental Science & Technology
• 出版年：2011
• 出版时间：December 15, 2011
• 年：2011
• 卷：45
• 期：24
• 页码：10378-10384
• 全文大小：858K
• 年卷期：v.45,no.24(December 15, 2011)
• ISSN：1520-5851

文摘

Study of the dispersion of persistent organic pollutants (POPs) throughout the environment is necessitated by their toxicological properties and propensity to accumulate in biota. In this study, we use data from the analysis of three ²¹⁰Pb dated soil profiles collected along a 30-m hydrological gradient to demonstrate postdepositional mobility of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs). We found that (i) humus originating from litter exposed to surface fallout during the 1960鈥?970s contains the highest concentrations of PCDD/Fs and PCBs in the O-horizon of the soils; (ii) accumulation rates of PCDD/Fs and PCBs in the O-horizon (5.0 and 210 渭g m^鈥? yr^鈥?) constituted only 9.1% and 3.5%, respectively, of the measured annual input, demonstrating that a minor fraction of the deposited material is retained within the O-horizon; (iii) POP inventories in the upper 0.5鈥?.9 m of the mineral soil constituted a considerable part (40鈥?0%) of the total pool stored in the soil, implying significant vertical translocation of atmospheric derived POPs; and (iv) increasing downslope inventories of POPs suggest a lateral downward transport of POPs from uphill soils. The findings challenge the commonly accepted view that POPs fallout is effectively retained within O-horizons.