Effects of atmospheric deposition, soil pH and acidification on heavy ...

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Abstract. The effects of acidification on the soil chemistry and plant availability of the metals Pb, Cd, Zn, Cu, Mn and Ni in new and archived soil and plant ...
Plant and Soil 240: 235–251, 2002. © 2002 Kluwer Academic Publishers. Printed in the Netherlands.

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Effects of atmospheric deposition, soil pH and acidification on heavy metal contents in soils and vegetation of semi-natural ecosystems at Rothamsted Experimental Station, UK L. Blake1 and K.W.T. Goulding Soil Science Department, IACR Rothamsted, Harpenden, Herts AL5 2JQ, UK 1 Corresponding author∗ Accepted in revised form 18 January 2002

Key words: Acid deposition, Heavy metals, Land use, Liming, Metal mobilization, Soil acidification

Abstract The effects of acidification on the soil chemistry and plant availability of the metals Pb, Cd, Zn, Cu, Mn and Ni in new and archived soil and plant samples taken from the >100-year-old experiments on natural woodland regeneration (Geescroft and Broadbalk Wildernesses) and a hay meadow (Park Grass) at Rothamsted Experimental Station are examined. We measured a significant input of metals from atmospheric deposition, enhanced under woodland by 33% (Ni) to 259% (Zn); Pb deposition was greatly influenced by vehicle emissions and the introduction of Pb in petrol. The build up of metals by long-term deposition was influenced by acidification, mobilization and leaching, but leaching, generally, only occurred in soils at pH