• Journal of the Korean earth science society
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• v.21 no.5
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• pp.611-622
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• 2000

To investigate the exchange rates of mercury(Hg) across soil-air boundary, we undertook the measurements of Hg flux using gradient technique from a major waste reclamation site, Nan-Ji-Do. Based on these measurement data, we attempted to provide insights into various aspects of Hg exchange in a strongly polluted soil environment. According to our analysis, the study site turned out to be not only a major emission source area but also a major sink area. When these data were compared on hourly basis over a full day scale, large fluxes of emission and deposition centered on daytime periods relative to nighttime periods. However, when comparison of frequency with which emission or deposition occurs was made, there emerged a very contrasting pattern. While emission was dominant during nighttime periods, deposition was most favored during daytime periods. When similar comparison was made as a function of wind direction, it was noticed that there may be a major Hg source at easterly direction to bring out significant deposition of Hg in the study area. To account for the environmental conditions controlling the vertical direction of Hg exchange, we compared environmental conditions for both the whole data group and those observed from the wind direction of strong deposition events. Results of this analysis indicated that the concentrations of pollutant species varied sensitively enough to reflect the environmental conditions for each direction of exchange. When correlation analysis was applied to our data, results indicated that windspeed and ozone concentrations best reflected changes in the magnitudes of emission/deposition fluxes. The results of factor analysis also indicated the possibility that Hg emission of study area is temperature-driven process, while that of deposition is affected by a mixed effects of various factors including temperature, ozone, and non-methane HCs. If the computed emission rate is extrapolated to the whole study area we estimate that annual emission of Hg from the study area can amount to approximately 6kg.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.1
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• pp.97-105
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• 2008

Nitrogen budgets in Korea in 2005 were estimated using a mass balance approach. Major nitrogen fluxes were divided into three sections: cities, agricultural area, and forest. Nitrogen inputs were chemical and biological fixation, dry and wet deposition, imported food and feed, while crop uptake, volatilization, denitrification, leaching, runoff, and forest consumption were nitrogen outputs. Non-point source(NPS) pollution budgets were also estimated by mass balance approach. Annual total nitrogen inputs budgets were 1,442,254 ton$\cdot$yr$^{-1}$, and outputs were 814,415 ton$\cdot$yr$^{-1}$. Approximately 19.4% of nitrogen input leaked to river and seawater as NPS pollution. It contains nitrogen input 21 percent more than the previous research in 2002. Especially the change of government plans affect nitrogen budget. As a result, in the output field, the whole nitrogen amount due to landfill reduce from 20 percent to less than 1 percent.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.2
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• pp.103-112
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• 2011

The main objective of this research was to estimate Nitrogen budget of South Korea in 2008. Input-output budgets for nitrogen fluxes were categorized into three sections: cities, agricultural area, and forest. Chemical and biological fixation, dry and wet deposition, imported food and feed were used as the nitrogen input. Crop uptake, volatilization, denitrification, leaching, runoff, and forest consumption were used as the nitrogen outputs. Annual total nitrogen input was 1,294,155 ton/yr, and output was 632,228 ton/yr. Comparison with a previous research in 2005 indicates that nitrogen input was decreased by 1.9% due to the decrease in nitrogen fertilizer while nitrogen output was decreased by 6.3%. Non-point source (NPS) pollution was also estimated by mass balance approach, which increased by 22% than the previous research in 2005. The emission of nitrous oxide ($N_2O$) caused by denitrification was newly examined in this research. About 8,289 ton/yr of $N_2O$ was released from agriculture area and domestic wastewater treatment plant.