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This study analyses the effect of a specific kind of soil development, podzolisation, on selected radionuclide concentrations and the derived dose rates. 100 samples from four sandy, podzolised regions in Jutland, Denmark, were dated by luminescence dating. Dose rates were determined by gamma spectrometry. Of the 100 samples, 31 were retrieved from three profiles intersecting soil horizons affected by podzolisation. At 35 locations, additional material was collected for supplementary geochemical analyses (soil pH, organic carbon content and extractable iron and aluminium). The geochemical data and grain size data were correlated with radionuclide activity concentrations. These correlations do not indicate any significant relationship between organic carbon or extractable iron/aluminium and radionuclide concentrations; this suggests that the radionuclides are mainly internally bound in primary minerals, unlike the extractable iron, which is generally associated with surface coatings. We conclude that the radionuclide distribution in these young sandy soils has been relatively unaffected by the podzolisation process. Thus it appears that the dose rate at these sites is unlikely to have changed significantly with time as a result of podzolisation, because the parent material is relatively unweathered and the activity is dominated by internally bound radionuclides.

M. 2010. Soil development rates from an optically stimulated luminescence-dated beach ridge sequence in Northern Jutland, Denmark. Can. J. Soil Sci. 90: 295Á307. Rates of podzolic soil development in sandy, temperate soils were quantified based on 14 soil pedons with five substrata from a beach ridge chronosequence near Jerup, Northern Denmark (578N). Soil pH, organic carbon (C) as well as extractable iron (Fe) and aluminium (Al) were measured. The age of each pedon and soil stratum was measured by optically stimulated luminescence (OSL) dating and used to estimate soil development rates. Soils were divided into five groups from Typic Haplorthods and Entic Alorthods with a mean OSL age of 29659294 yr to Typic Quartzipsamments with a mean OSL age of 22911 yr. Acidification rates during the first 200 yr were Â1.9 pH units per 100 yr in the A horizons and C-sequestration rates wereÂ25 g C m (2 yr(1 (excluding litter accumulation). After Â1500 yr, the mineral soil C stocks stabilised around 13.092.0 kg C m (2 . Translocation rates of Al into B horizons were Â0.3 kg Al m (2 per 1000 yr, while translocation rates for Fe were scattered. Our study illustrates the potential of OSL dating in chronosequence studies to quantify soil development rates.Key words: Soil development rates, chronosequence, OSL-dating, C-sequestration rates and translocation rates Nielsen, A. H., Elberling, B. et Pejrup, M. 2010. Taux de de´veloppement du sol dans une se´quence de ride de plage date´e par luminescence stimule´e optiquement dans le nord du Jutland, au Danemark. Can. J. Soil Sci. 90: 295Á307. Les auteurs ont quantifie´le taux de de´veloppement des podzols dans un sol tempe´re´sablonneux a`partir de 14 pe´dons incluant 5 sousstrates issues d'une chronose´quence pre`s de Jerup, dans le nord du Danemark (578N). Ils ont mesure´le pH du sol, la concentration de carbone organique (C) ainsi que la proportion de fer (Fe) et d'aluminium (Al) extractible. L'aˆge de chaque pe´don et strate a e´te´e´tabli par luminescence stimule´e optiquement (LSO) ce qui a permis d'estimer le taux de de´veloppement du sol. Les sols ont e´te´re´partis en cinq groupes, de l'haplorthod typique a`l'alorthod entique, dont la LSO moyenne est de 2 9659294 ans, aux quartzipsamments typiques, dont la LSO moyenne se chiffre a`22911 ans. Le taux d'acidification au cours des 200 premie`res anne´es e´tait deÂ1,9 unite´pH par sie`cle pour les horizons A, tandis que le taux de se´questration du C s'e´tablissait a`Â25 g par m 2 et par anne´e (sans la couverture de´tritique). Apre`s Â1500 ans, la re´serve de C du sol se stabilise autour de 13,092,0 kg par m 2 . La translocation de l'Al dans les horizons B se situe a`Â0,3 kg par m 2 par 1 000 ans alors que celle du Fe varie. L'e´tude re´ve`le le potentiel de la me´thode de datation par LSO dans l'e´tude des chronose´quences pour mesurer le taux de de´veloppement du sol.

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