ISSN:
1573-515X
Keywords:
adsorption
;
bacterial dissimilatory sulfate reduction
;
dry deposition
;
forested catchment
;
Lake Gårdsjön
;
isotopes
;
oxidation of sulfur
;
sulfate
;
sulfur
;
Sweden
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Geosciences
Notes:
Abstract A small catchment on the Swedish West Coast has been studied over four years to determine S dynamics by using S isotope ratios. A Norway spruce dominated forest covers the catchment, and small peat areas occur in the lower parts of the catchment. The runoff $$\delta ^{34} S_{SO_4 } $$ values varied both during the year, and from year to year. Over the period from February 1990 to December 1993, the $$\delta ^{34} S_{SO_4 } $$ values ranged from — 1%. to +11%. Over the same period, the throughfall $$\delta ^{34} S_{SO_4 } $$ values ranged from +1%. to +15%. There was no correlation (r 2= 0.01; Pr(F)=0.57) between $$\delta ^{34} S_{SO_4 } $$ values in throughfall and runoff. Since the only input of S to the catchment is atmospheric deposition, the long-term runoff S mass flux is controlled by the deposition. Therefore, processes in the catchment are responsible for the variation in the runoff $$\delta ^{34} S_{SO_4 } $$ values. During periods with $$\delta ^{34} S_{SO_4 } $$ enriched runoff, bacterial dissimilatory SO 4 2− reduction occurs in the catchment. After very dry periods, oxidation of this reduced S, which is32S-enriched, can be traced in runoff. Previous studies of the catchment have not been able to distinguish between: 1) oxidation of reduced S and dry deposition, and 2) reduction and adsorption. From the current study, it can be concluded that adsorption and dry deposition cannot cause the observed variation in runoff $$\delta ^{34} S_{SO_4 } $$ .
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00992998
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