wAbstract
@Rock samples and the C-, B- and O-horizons of soils developed
on these rocks were collected in forested areas along a 120-km
south-north transect in southern Norway, passing through the city
of Oslo. Forty samples (1 site/3 km) were analysed for 37 chemical
elements (Ag, Al, As, Au, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, Ga,
Hg, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sb, Sc, Se, Sr, Te, Th,
Ti, Tl, U, V, W and Zn) following an aqua regia digestion; pH
(water extract) and loss on ignition were also determined. The
O-horizon soils were additionally analysed for Pt. Gold is the
only element that shows a clear anthropogenic peak in the O-horizon
soils collected from the city of Oslo. silver, Au, Bi, Cd, Hg,
Pb, S, Sb, Se and Sr all show a strong enrichment in the O-horizon
when compared to the underlying C-horizon or the bedrock along
the full length of the transect. Neither geology nor anthropogenic
input of elements dominate the observed patterns. The most important
factors for the observed element concentrations in the O-horizon
are weathering, uptake (or rejection) of elements by plants and
the kinetics of decay of the organic material in the O-horizon.
Climate, especially temperature and precipitation, has an important
influence on the formation and decay rates of the organic soil
layer. Acid precipitation will delay the decomposition of the
organic layer and lead to a natural enrichment of several metals
in the O-horizon. Land use change, deforestation and liming can
all increase the decay kinetics of organic matter and thus result
in a release of the stored element pool.x
1. Introduction
@1.1. Location and land use
@1.2. Geology
2. Sampling and analytical methods
@2.1. Quality control
3. Results
@3.1. Gold and platinum in the O-horizon samples
@3.2. Loss on ignition and pH in the O-horizon-samples
@3.3. Elements generally enriched in the O-horizon
@3.4. Elements showing different patterns along transect
@3.5. Relation of the elements with pH and LOI in the O-horizon
samples, principal component analysis
4. Conclusions
Acknowledgements
References