Biogenic sulfur emissions

Andreae, M. O., W. Elbert, and S. J. de Mora, Biogenic Sulfur Emissions and Aerosols over the Tropical South Atlantic. 3. Atmospheric Dimethylsulfide, Aerosols, and Cloud Condensation Nuclei, J. Geophys. Res., 100, 11335-11356 (1995). 

To review the extant data base of biogenic sulfur emissions for terrestrial and oceanic environments and to summarize direct estimates of emissions where possible. 

This topic is included in order to complete a discussion of biogenic sulfur emissions. The reader is referred to more comprehensive reviews m this book and other sources for more details (e.g. 69-731. 

Adams, D. F. Farwell, S. O. Biogenic Sulfur Emissions in the SURE and Extended SURE Regions Final Report, EPRI Proj 856-1 and 856-2 Electric Power Research Institute Palo Alto, CA, 1980 F- p 13. 

A U. S. national biogenic sulfur emissions inventory with county spatial and monthly temporal scales has been developed using temperature dependent emission algorithms and available biomass, land use and climatic data. Emissions of dimethyl sulfide (DMS), carbonyl sulfide (COS), hydrogen sulfide (H2S), carbon disulfide (CS2), and dimethyl disulfide (DMDS) were estimated for natural sources which include water and soil surfaces, deciduous and coniferous leaf biomass, and agricultural crops. The best estimate of 16100 MT of sulfur per year was predicted with emission algorithms developed from emission rate data reported by Lamb et al. (1) and is a factor of 22 lower than an upper bound estimate based on data reported by Adams et al. 

GUENTHER ETAL VS. National Biogenic Sulfur Emissions Inventory... 

The relative contribution that each reduced sulfur compound makes to the total sulfur flux is often of interest because the various compounds behave differently once they enter the atmosphere. Terrestrial biogenic sulfur emissions are dominated by COS (38%), DMS (35%) and H2S (21%). Emissions of CS2 and DMDS together represent about 6% of the total. DMS emissions dominate during the summer season with 41% of the total. 

Table VII. Comparison of Anthropogenic and Biogenic Sulfur Emissions...

Variability in Biogenic Sulfur Emissions from Florida Wetlands... 

Within the . alterniflora fringe, spatial variability in both the magnitude and speciation of biogenic sulfur emissions was found to reflect the inhomogeneity of vegetation coverage. This is vividly demonstrated in the data shown in Table I, a summary of measurements made within the Spartina fringe. DMS and H2S measurements were made from the same chambers, and all sites were within S meters of each other. The variations can be explained by the relative contributions to the total emission from soil bacteria versus plant... 

Patterns of biogenic sulfur emissions show components due to tidal, diel, spatial, and seasonal effects. Emissions of DMS and H2S show different temporal patterns, reflecting these various components, and also reflecting the different metabolic effects leading to their formation. DMS and H2S emissions are 2-3 orders of magnitude greater than those of CS2 and DMDS. 

Biogenic Sulfur Emissions from the Ocean. The ocean is a source of many reduced sulfur compounds to the atmosphere. These include dimethylsulfide (DMS) (2.4.51. carbon disulfide (CS2) (28). hydrogen sulfide (H2S) (291. carbonyl sulfide (OCS) (30.311. and methyl mercaptan (CH3SH) ( ). The oxidation of DMS leads to sulfate formation. CS2 and OCS are relatively unreactive in the troposphere and are transported to the stratosphere where they undergo photochemical oxidation (22). Marine H2S and CH3SH probably contribute to sulfate formation over the remote oceans, yet the sea-air transfer of these compounds is only a few percent that of DMS (2). 

Summary of Biogenic Sulfur Emissions from the Ocean. To summarize the source fractionation patterns for biogenic sulfur emissions from the oceam a simple isotopic model has been constructed (Figure 1). From this, the S S value of sulfate from a marine biogenic source of atmospheric sulfur can be estimated. 

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