Global uptake of carbonyl sulfide (COS) by terrestrial vegetation: Estimates corrected by deposition velocities normalized to the uptake of carbon dioxide (CO₂)

L. Sandoval-Soto (1) , M. Stanimirov (2) , M. von Hobe (3) , Vivien Schmitt (4) , J. Valdes (5) , A. Wild (4) , J. Kesselmeier (1)

1 MPIC - Max Planck Institute for Chemistry
2 University of Applied Sciences Solothurn
3 Research Centre Jülich
4 Institute for General Botany
5 LAQAT - Laboratorio de Química de la Atmosfera [Heredia]

COS uptake by trees, as observed under dark/light changes and under application of the plant hormone abscisic acid, exhibited a strong correlation with the CO₂ assimilation rate and the stomatal conductance. As the uptake of COS occurred exclusively through the stomata we compared experimentally derived and re-evaluated deposition velocities (V_d for COS and CO₂). We show that V_d of COS is generally significantly larger than that of CO₂. We therefore introduced this attribute into a new global estimate of COS fluxes into vegetation. The global COS uptake by vegetation as estimated by the new model ranges between 0.69-1.40 Tg a^-1, based on the Net Primary Productivity (NPP). Taking into account Gross Primary Productivity (GPP) the deposition estimate ranges between 1.37-2.81 Tg a^-1 (0.73-1.50 Tg S a^-1). We believe that in order to obtain accurate and reliable global NPP-based estimates for the COS flux into vegetation, the different deposition velocities of COS and CO₂ must be taken into account.

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]; Astrophysique [astro-ph]; Interfaces continentales, environnement; Océan, Atmosphère; Sciences de la Terre

L. Sandoval-Soto, M. Stanimirov, M. von Hobe, Vivien Schmitt, J. Valdes, et al.. Global uptake of carbonyl sulfide (COS) by terrestrial vegetation: Estimates corrected by deposition velocities normalized to the uptake of carbon dioxide (CO₂). Biogeosciences Discussions, 2005, 2 (1), pp.183-201. ⟨hal-00297730⟩