IngentaConnect The Missing Flux in a 35S Budget for the Soils of a Small Pollute...

Abstract:

A combination of cosmogenic and artificial ³⁵S was used to assess the movement of sulfur in a steep Central European catchment affected by spruce die-back. The Jeze rcaron

í catchment, Kru scaron

né Hory Mts. (Czech Republic) is characterized by a large disproportion between atmospheric S input and S output via stream discharge, with S output currently exceeding S input three times. A relatively high natural concentration of cosmogenic ³⁵S (42 mBq L^-1) was found in atmospheric deposition into the catchment in winter and spring of 2000. In contrast, stream discharge contained only 2 mBq L^-1. Consequently, more than 95% of the deposited S is cycled or retained within the catchment for more than several months, while older S is exported via surface water. In spring, when the soil temperature is above 0 °C, practically no S from instantaneous rainfall is exported, despite the steepness of the slopes and the relatively short mean residence time of water in the catchment (6.5 months). Sulfur cycling in the soil includes not just adsorption of inorganic sulfate and biological uptake, but also volatilization of S compounds back into the atmosphere. Laboratory incubations of an Orthic Podzol from Jeze rcaron

í spiked with 720 kBq of artificial ³⁵S showed a 20% loss of the spike within 18 weeks under summer conditions. Under winter conditions, the ³⁵S loss was insignificant (<5%). This missing S flux was interpreted as volatilized hydrogen sulfide resulting from intermittent dissimilatory bacterial sulfate reduction. The missing S flux is comparable to the estimated uncertainty in many catchment S mass balances (±10%), or even larger, and should be considered in constructing these mass balances. In severely polluted forest catchments, such as Jeze rcaron

í, sulfur loss to volatilization may exceed 13 kg ha^-1 a^-1, which is more than the current total atmospheric S input in large parts of North America and Europe.

Keywords: catchment; cosmogenic 35 S; gaseous S~loss; sulfur

Document Type: Research article

DOI: 10.1023/B:WAFO.0000028375.96356.eb

Affiliations: 1: Czech Geological Survey, Geologická 6, 152 00 Prague 5, Czech Republic (author for correspondence, novak@cgu.cz; phone: +4202 51085333;, Fax: +4202 51818748), Email: novak@cgu.cz 2: U.S. Geological Survey, 345 Middlefield Road, MS 434, Menlo Park, CA 94025, U.S.A. 3: Czech Geological Survey, Geologická 6, 152 00 Prague 5, Czech Republic

The full text electronic article is available for purchase. You will be able to download the full text electronic article after payment.

$47.00 plus tax Refund Policy

The Missing Flux in a 35S Budget for the Soils of a Small Polluted Catchment

The Missing Flux in a ³⁵S Budget for the Soils of a Small Polluted Catchment