W. Jaeschke et al., MEASUREMENTS OF REDUCED SULFUR-COMPOUNDS IN AN INDUSTRIALIZED TROPICAL REGION - CUBATAO (BRAZIL), International journal of environmental analytical chemistry, 54(4), 1994, pp. 315-337
Ambient concentrations of SO2, H2S, COS and CS2 has been determined at
various sites in the highly industrialized area of Cubatao (Brazil) a
nd in adjacent ecosystems during the years 1990 to 1993. Sulphate has
been analyzed in rain samples collected at three sites in the Serra do
Mar. The sites are called Vale do Mogi (heavily polluted), Paranapiac
aba (moderately polluted), and Vale do Piloes (less polluted). Gas exc
hange of reduced sulphur compounds between biosphere and atmosphere ha
s been examined with the aid of ambient air enclosures. The investigat
ed sulphur sources (and sinks) were the estuaries South of Cubatao, a
reservoir north of Cubatao, and vegetated soils at Vale do Mogi, Paran
apiacaba, and Vale do Piloes. The content of reduced sulphur compounds
was determined in surface water samples from lakes, rivers, and estua
ries in the area under investigation. We sulphate deposition and ambie
nt SO2 concentrations revealed a similar hierarchy of Vale do Mogi, Pa
ranapiacaba, and Vale do Piloes confirming the assumed pollution level
s. In addition all investigated sites showed considerably elevated amb
ient concentrations of H2S, COS, and CS2 when exposed to industrial em
issions. Emissions from biogenic sources are dominant over the Billing
s reservoir and over the estuaries. Flux measurements showed emissions
of DMS and CH3SH from vegetated soils. Deposition or uptake were obse
rved with respect to H2S, COS, and CS2 mainly due to high ambient conc
entrations of these gases. DMS, COS, and CH3SH were present in most of
the water samples analysed. Maximum DMS concentrations have been dete
cted in anoxic freshwater and estuarine water.