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Title:
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Report on the activities of the international consultant, Prof. J. Slanina, in the project: 'Capacity development for acid rain and SO2 pollution in Guiyang' for the year 1999: project number: CPR/96/304/A/01/99
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Author(s):
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Published by:
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Publication date:
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ECN
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1-12-1999
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ECN report number:
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Document type:
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ECN-C--99-096
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ECN publication
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Number of pages:
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Full text:
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24
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Download PDF
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Abstract:
The acid deposition loads in the Chinese province Guizhou near Guiyangare very high, as indicated by ambient concentration measurements at two
locations, North of Guiyang. Both are frequently exposed to pollutants
emitted by Guiyang. One site (at Zhazuo) is in a valley, the other,
Yunwushan, is on a mountain (1600 meter, about 600 meter over the average
altitude of the surroundings). This combination is chosen not only in order
to be able to measure cloud and fog water composition, but it can safely be
assumed that the measurements at higher elevation represent a more regional
situation compared to local influences at Zhazuo in the valley. The found
values of 14.500 and 16.000 moles of potential acid per hectare per year
agree reasonably well with the assessments made in the last report, based on
throughfall data. It is very clear that nitric acid and nitrate (yet)
constitute a minor contribution. But the contribution of ammonia (due to the
use of fertilizer in rice fields and to untreated sewage) has quite a large
contribution, in the order of 25%. These rather sizable nitrogen deposition
fluxes caused by ammonia do not only contribute to the total amount of acid
deposition but lead to eutrophication, too high nutrient fluxes, which will
cause effects as eutrophication (algae blooms) of lakes and too high
concentration of nitrate in groundwater (ground water containing more than 25
milligram of nitrate per liter should not be used as drinking water according
to European regulations, due to the cancerogenic effect of nitrate). The
contribution of occult deposition (deposition by way of fog and cloud
droplets) is indeed important, as already expected. The highest contribution
is observed at Yunwushan at higher elevations, about 30%. The contribution at
Zhazuo is probably lower, about 15%. The uncertainty in these estimates, in
view of the lack of meteorological data is very large. The data indicate that
indeed in the order of half the acid deposition at locations such as Zhazuo
and Yunwushan is caused by local sources (to be specific probably by the
emissions of Guiyang) but the other half is caused by Long Range Transport of
gases and aerosols. Emission abatement in the city of Guiyang, even if this
process is 100% successful can only diminish acid deposition with about 50%.
Obviously, as reported already earlier, the ambient sulfur dioxide
concentrations encountered in Guiyang were so high as directly endangering
human health. Measures taken in the past and future plans will indeed
alleviate these problems considerably. The present plans for control of
emissions, monitoring of deposition and occult deposition look fine and
should ensure that the positive effects of emission abatement measures can be
followed and optimized. As already stated, the plans for emission abatement
are very good indeed, only care should be taken to implement the plans in
such a way that transient environmental problems can be avoided. The main
reason that severe effects have not yet been encountered seems to be in-situ
neutralization of sulfuric acid by calcium carbonate dust, which is present
in high concentrations in Guizhou province. A new emission inventory,
describing a much larger area has been prepared. Measures taken in the past
and future plans will indeed alleviate the air pollution problems
considerably. As already stated, the plans for emission abatement are very
good indeed, only care should be taken to implement the plans in such a way
that transient environmental problems can be avoided, e.g. by reducing dust
loads before sulfur reduction takes place. The present plans for control of
emissions, monitoring of deposition and occult deposition look fine and
should ensure that the positive effects of emission abatement measures can be
followed and optimized. The participants in this project have been confronted
with very unexpected situations (very high deposition loads, unsuitable
conditions for envisaged measurements etc.), but have managed to adapt the
direction of their in order to the necessary results
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