Comparison of elemental contents in O- and C-horizon soils from the surroundings of Nikel, Kola Peninsula, using different grain size fractions and extractions

• Published in: Geoderma Vol. 84; no. 1; pp. 65 - 87
• Main Authors: Reimann, Clemens, de Caritat, Patrice, Niskavaara, Heikki, Finne, Tor Erik, Kashulina, Galina, Pavlov, Vladimir A
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.06.1998
• Subjects: element availability; heavy metals; multi-element geochemistry; regional mapping; smelter emissions; soil geochemistry; multi-element geochemistry; regional mapping; soil geochemistry; smelter emissions; heavy metals; element availability
• ISSN: 0016-7061; 1872-6259
• DOI: 10.1016/S0016-7061(97)00121-3

Forty-five soil samples from the O- and C-horizons were taken in a 12,000 km 2 area on the borders of Finland, Norway and Russia. The nickel smelter at Nikel, the ore roasting plant at Zapoljarnij, both in Russia, and the iron ore mine and processing plant at Kirkenes in Norway, are all situated within this area. Element levels and variation in both soil horizons (two different extractions of the O-horizon and two different grain size fractions of the C-horizon) are presented and discussed. No good correlation exists between element concentrations measured in the O-horizon and the parent C-horizon. Of the 30 analysed elements, 7 are clearly enriched (>2×) in the O-horizon, while 11 show higher concentrations (>3×) in the C-horizon. In Russia, near industry, a number of heavy metals (Co, Cu, Ni) show extreme enrichments in the O-horizon soils. All the anthropogenic contaminants show a marked decrease in element concentrations from the Russian nickel industry towards the west in the O-horizon samples. Chemistry of the C-horizon is very little affected by the emissions. For the O-horizon samples, a close correlation was observed between 1 M ammonium acetate- and concentrated nitric-acid extractable element concentrations. Element availability in 1 M ammonium acetate, however, differs widely from 65% (K) to less than 1% (Si, Ti). Of the heavy metals examined, Cd and Zn are most readily extractable. Copper is more strongly bound in the O-horizon than Ni or S. Interestingly, Na, K, Mg and P are less available at sites affected by emissions from industry than in background areas. Element content and variation are generally higher in the <0.063 mm than the <2 mm fraction of the C-horizon samples by a factor of 1.6 to 2.8. In addition, correlation between O-horizon and C-horizon chemistry is higher for the fine fraction of the C-horizon. The fine fraction of mineral soils is thus considered more appropriate for the detection of element sources and for mapping regional differences than the <2 mm fraction. Comparison of the results of the two extractions used for the O-horizon samples and the two fractions used to analyse the C-horizon samples helps to distinguish anthropogenic from geogenic element sources.