Measurements of the exchange of carbonyl sulfide (OCS) and carbon disulfide (CS2) between soil and atmosphere in a spruce forest in central Germany

The exchange of carbonyl sulfide (OCS) and CS2 between the atmosphere and the pedosphere was investigated in a temperate zone spruce forest in the Solling Mountains (51°N), Germany during three field campaigns in 1999. Dynamic (flow-through) chambers were used to measure the OCS and carbon disulfide (CS2) exchange fluxes between the soil and the atmosphere. All measurements showed a net OCS flux from the atmosphere into the soil. On average (± standard error of the mean), the OCS uptake rate of the soil was and the total range was between 0.23 and . CS2 fluxes varied between an uptake of and an emission of . Therefore, CS2 is emitted by the soil in a nearly balanced mean flux of . Slight dependencies of the OCS flux on soil temperature and soil water content were detected. The fluxes varied by about a factor of 2 over a distance of 10 m. A comparison of the OCS fluxes between soil and atmosphere with the fluxes observed simultaneously above the canopies revealed that only 1% of the OCS which was taken up by the whole forest ecosystem is deposited in the soil. The impact of the CS2 exchange between soil and atmosphere for the whole ecosystem flux of CS2 was even more negligible.