Chemical Composition of Post-Harvest Biomass Burning Aerosols in ...

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Chemical Composition of Post-Harvest Biomass Burning Aerosols in ...

Chemical Composition of Post-Harvest Biomass Burning Aerosols in

Gwangju, Korea

Seong Y. Ryu 1 , Jeong E. Kim 1 , Zhuanshi H. 1 , Young J. Kim 1,* , and Gong U. Kang 2

1 ADvanced Environmental Monitoring Research Center, Department of Environmental

Science and Engineering, Kwangju Institute of Science and Technology, Gwangju, Republic

of Korea

2 Department of Environmental Science, Wonkwang Health Science College, Iksan, Republic

of Korea

Submitted to

PM 2003 Special issue of

the Journal of the Air & Waste Management Association

Submitted 9 July 2003

Revised 17 January 2004

Advanced Environmental Monitoring Research Center (ADEMRC),

Department of Environmental Science and Engineering

Kwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu,

Gwangju, 500-712, Republic of Korea

* Corresponding author

(FAX number : 82-62-970-3404; e-mail address : yjkim@kjist.ac.kr)

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ABSTRACT

The main objective of this study was to investigate the chemical characteristics of post-

harvest biomass burning aerosols from field burning of barley straw in late spring and rice

straw in late fall in rural areas of Korea. A 12-hr integrated intensive sampling of PM10 and

PM2.5 biomass burning aerosols had been conducted continuously in Gwangju, Korea

during two biomass burning periods: June 4-15, 2001 and October 8 through November 14,

2002. The fine and coarse particles of biomass burning aerosols were analyzed for mass,

ionic, elemental, and carbonaceous species. The average fine and coarse mass

concentrations of biomass burning aerosols were respectively 129.6 and 24.2 µgm -3 in June

2001, and 47.1 and 33.2 µgm -3 in October through November 2002. An exceptionally high

PM2.5 concentration of 157.8 µgm -3 was observed during biomass burning events under

stagnant atmospheric conditions. In the fine mode, Cl - and K + were unusually rich due to

the high content of semi-arid vegetation. Both organic carbon and elemental carbon

increased during the biomass burning periods, with the former exhibiting a higher

abundance. Particulate matter from the open field burning of agricultural waste has an

adverse impact on local air quality and regional climate.

Keywords: biomass burning aerosol, chemical composition, fine particles, dust aerosol

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INTRODUCTION

Biomass burning is a widespread, annually occurring phenomenon that is used to

clear land for cultivation, convert forests to agricultural lands, and remove vegetation in

order to promote agricultural productivity and growth of high-yield grasses. Biomass

burning aerosols have been recognized as a globally important source of trace gases and

atmospheric particulate matter. 1 Trace gases and particulate matter from biomass burning

over many parts of the world have been studied by many reserchers 2-9 especially on the

African continent and in tropical forest regions such as the Savanna, the Amazon basin, and

Southeast Asia. These regions have been recognized as major sources of biomass burning

and produce significant amounts of man-made, radiatively active carbon-containing

aerosols in the atmosphere. Biomass burning aerosols consist of two major chemical

components: black carbon, which primarily absorbs solar radiation, and organic carbon,

which primarily scatters solar radiation. The strongest negative force is associated with

regions of intense biomass burning activity, and differs from regions where the sulphate

radiative force is the strongest. The global, annual mean radiative force due to biomass

burning aerosols is estimated as -0.2 Wm -2 . 10

The haze problem in the Asian region is particularly acute because of the large

increase in emissions and the extended dry season, which prevents washout of the pollution

from the atmosphere. Due to long-range transport, the mostly urban (fossil fuel related) and

rural (biomass burning related) aerosols are transformed into a regional haze or cloud that

can span an entire continent or the whole of the North Pacific. 11

In Korea, open field burning of agricultural waste after harvest is commonly

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practiced by many farmers. Atmospheric particulate matter from both long-range

transported Asian dust and anthropogenic sources directly affect the particulate pollution in

Gwangju, Korea. There are two typical biomass burning phenomena in Korea: one is the

burning of agricultural waste after the harvesting of barley in late spring, and the other is

the burning that follows the harvesting of rice in the fall. The high concentration of fine

particulate matter resulting from these events produces adverse effects on local air quality,

human health, and a degradation in visibility. Figure 1 shows the annual variation of PM10

concentration measured at a Ministry of Environment air monitoring station in Gwangju,

Korea in 2001. It indicates a very high PM10 concentration of 150 µgm -3 over the 24-hr air

quality standard period, which occurs in the spring and fall during Asian dust storm and

biomass burning episodes.

The particulate matter directly influenced by agricultural biomass open burning has

been collected and analyzed in this study to characterize its chemical composition and

assess its impact on air quality. An investigation and analysis was made of the chemical

composition characteristics of aerosols released from the burning of barley stray in the late

spring and rice straw in the late fall. An unusual Asian dust event was also observed during

the intensive sampling period in the fall. Differences in the chemical composition between

biomass burning aerosols and other types of aerosols, including Asian dust and urban

pollution in Gwangju, Korea, were also investigated.

EXPERIMENTAL METHODS

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Post-harvest biomass burning aerosols were collected in Gwangju, Korea (35.10N,

126.53E) during two intensive periods: June 4-15, 2001 and October 8 through November

14, 2002. As shown in Figure 2, the sampling site is located in the city of Gwangju, which

is the fifth largest city in Korea and located 330 km south of Seoul. Its population of

approximately 1.4 million people occupies an area of 501.4 km 2 in which there are also 0.3

million motor vehicles. Aerosol sampling was conducted in a mobile laboratory trailer on

the rooftop of one of the buildings at the Kwangju Institute of Science and Technology

(KJIST), which is located in a northern suburb of Gwangju. The Hanam industrial complex

is located several kilometers southwest from the sampling site. The general meteorological

weather conditions in Gwangju are characterized by a cool and dry fall from September to

November, and a hot and humid summer from June to August. The prevailing wind at

Gwangju is southwesterly in June and northwesterly in October and November. Thus the air

quality of this region is affected by urban and industrial emissions, the burning of

agricultural waste and long-range transported pollutants.

A total of 51 12-hr integrated PM2.5 and PM10 samples were collected using an

URG Versatile Air Pollutant Sampler (VAPS, URG-3000K) with a PM10 cyclone inlet, an

URG PM10 cyclone sampler (URG-2000-30ENB), and a Dichotomous PM10 sampler

(ASI/GMW series 241) on pre-baked quartz fiber filters for carbonaceous species, and on

Teflon filters for mass, ionic and elemental species analyses. The PM10 URG sampler is

equipped with an aluminum cyclone with a cut size of 10 µm operated at a 16.7 lpm flow-

rate. URG-VAPS and Dichotomous samplers were operated at a 32 lpm and 16.7 lpm flow-

rate, respectively. The 47mm quartz fiber filters for carbon analysis were preheated under

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550 furnace for 8 hours to minimize their carbon blanks, put in petri dishes, then wrapped

with Teflon tape and aluminum foil, and stored in a refrigerator before sampling. All

samples were refrigerated between collection and analysis after sampling to minimize

losses due to volatilization and evaporation during transportation. Fine and coarse fractions

of aerosol mass concentrations were obtained by a gravimetric method using an electronic

microbalance with a sensitivity of 1 µg. Samples collected from each intensive sampling

were analyzed by Ion chromatography (Dionex, DX-120) for concentrations of ionic

species (Na + , NH4 + , K + , Mg 2+ , Ca 2+ , Cl - , NO3 - , SO4 2- ). PM10 and PM2.5 samples collected on

quartz filters were analyzed at Atmospheric Assessment Associates (AtmAA), Calabasas,

CA, USA for analysis of carbonaceous species; elemental carbon (EC) and organic carbon

(OC) by the selective thermal oxidation method with a MnO2 catalyst. In the thermal

manganese dioxide oxidation (TMO) technique, the sample is heated in a He atmosphere in

contact with a bed of granulated manganese dioxide that supplies the O2 needed for

combustion. All of the OC is combusted in a single step at 525℃. The constant availability

of O2 from MnO2 and the rapid heating rate at the maximum temperature for OC all

contribute to minimizing pyrolysis of OC. EC is the residual carbon after the OC oxidation

is combusted at 750℃ in 2.5% O2/He and additional MnO2. 12 The fine and coarse samples

collected on the filters of the URG-VAPS sampler were used to analyze 22 species of the

trace elements; Na, Mg, Al, P, S, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd, Sb,

Ba, and Pb were analyzed using Inductively Coupled Plasma (ICP)-Atomic Emission

Spectrometry (AES) and ICP-MS (Mass Spectrometry) at the Korea Basic Science Institute,

Daejon, Korea. Meteorological data was collected by an automatic weather station (AWS)

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collocated at the sampling site. In order to assess the influence of air mass history on the

chemical composition of the sampled aerosol, backward trajectories of air parcels arriving

at the sampling site were calculated using the HYsplit (Hybrid Single-Particle Lagrangian

Integrated Trajectory) model developed by NOAA/ARL. 13 Two sets of three-day back

trajectories at three altitude levels (500, 1000, and 2000m AGL-Above Ground Level) were

computed for each sampling day at 0900 UTC and 2100 UTC.

RESULTS AND DISCUSSION

Aerosol mass concentration in fine and coarse modes

Table 1 summarizes the mass concentration of EC and OC, and major ion

concentrations in the fine (PM2.5) and coarse (PM10–PM2.5) modes for all sampling periods.

Table 1 shows the categorization of each sampling period into five distinct groups

according to aerosol event characteristics and meteorological and air mass history

conditions: (1) the biomass burning of barley straw in late spring (BBB), (2) the

background condition of a non-event (BG), (3) the urban pollution under stagnant

atmospheric conditions (UP), (4) the biomass burning of rice straw in late fall (BBR), and

(5) the biomass burning of rice straw plus Asian dust (BBR+AD).

Table 2 summarizes the results of the average concentrations of biomass burning

aerosols obtained in this study with the seasonal average values measured previously in

Gwangju by Kim et al., 2001. 14 Significant increases in fine mass concentration were

observed during both biomass burning events. Average fine and coarse mass concentrations

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of biomass burning aerosol in June 2001 were 129.6 and 24.2 µgm -3 , respectively, while

measurements of 47.1 and 33.2 µgm -3 were obtained in the fall of 2002. An exceptionally

high PM2.5 concentration of 65µgm -3 was observed during the intensive sampling period in

June 2001 and exceeded the 24-hour average US National Ambient Air Quality Standards

(NAAQS). 15 Figure 3 shows the variations of aerosol mass concentration in the fine and

coarse modes measured during the intensive sampling periods. Figure 4 shows examples of

the three-day air mass backwards trajectory results, including the stagnation phenomena on

June 10, 2001 and October 12-14, 2002, the northwesterly wind conditions on October 30,

2002, and the Asian dust storm conditions on November 11-12, 2002. Major wind direction

was southwesterly and southeasterly in June 2001, and northwesterly and southwesterly in

October to November 2002. Extremely high levels of fine mass concentration exceeding

the 24-hour average US NAAQS for PM2.5 were observed during the entire sampling period

in June 2001, with an average PM2.5/PM10 ratio of 0.84. As shown in Figure 4(a), aerosol

from the biomass burning of barley straw accumulated in the atmosphere under stagnant

meteorological conditions from June 4-14, 2001 at Gwnagju. Thus, exceptionally high fine

aerosol mass concentration was observed during that period, which impacted heavily on

local air quality.

Stagnation phenomena also appeared from October 12 to 14, 2002, during which

the prevailing wind direction was southwesterly and northwesterly. Emission from an

industrial complex located southwest of the sampling site caused a high mass concentration

during that period. During the two sampling days, November 11 th and 12 th , 2002 there was

an unusual event; Asian dust storms passed over Gwangju, in addition to local biomass

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urning as shown in Figure 4(d). Although the wind speed was high, and typical for an

Asian dust storm period, very high levels of mass concentration were measured in both fine

and coarse modes due to the biomass burning and dust particles. Air quality at the sampling

site was greatly affected by the biomass burning event, resulting in a high mass

concentration in the fine mode. Figure 5 presents the average mass concentration in both

fine and coarse modes for four different categories measured in 2002. On November 11 th

and 12 th , extremely high fine and coarse mode concentrations of 70.4 and 132.6 µgm -3 ,

respectively, were measured due to the combined effects of biomass burning and the Asian

dust storm.

Soluble ionic species

An analysis was made of the concentration of the soluble eight ionic species in the

fine and coarse mode; chloride, nitrate, sulfate, sodium, ammonium, potassium, magnesium,

and calcium concentrations were determined by Ion Chromatography (IC) analysis. The

major soluble species from biomass burning were chloride, nitrate, sulfate, ammonium, and

potassium. Table 3 summarizes the average concentration of ionic species and soil during

the intensive sampling periods. During the biomass burning period (BBB and BBR),

increases of Cl - , NO3 - , NH4 + and K + in fine mode were remarkable, while the level of SO4 2-

in fine mode, and that of NO3 - and Ca 2+ in coarse mode, increased during the Asian dust

period (BB+AD) in comparison to levels obtained during the background period (BG).

Potassium is a highly useful tracer for pyrogenic aerosols because the combustion of plant

matter, which contains K + as a major electrolyte within its cytoplasm, releases large

amounts of K-rich particles in the submicron size fraction. 8,16,17 Variations in the

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concentration of major ionic species showed similar patterns, while the tracer of biomass

burning potassium ion did not show a proportional increase in the fine fraction during the

biomass burning events. Andreae et. al. 8 reported that the major ionic species from savanna

fires were Cl - , SO4 2- , K + and NH4 + , and Yamasoe et. al. 9 found that the dominant ionic

species from fires of the Amazon basin were K + , Cl - , and SO4 2- , while Cl - , NO3 - , SO4 2- , and

NH4 + were the dominant ionic species in this study. The dominant anion in this study was

NO3 - , while Cl - was dominant in savanna fires and Amazon basin fires. 8,9 The differences

observed may be partially explained by the variability in biomass density, the amount of

water present in the vegetation before burning, and distinct vegetation elemental

composition. Agricultural waste burning in Korea is more dense and wet than cerrado and

tropical forest vegetation, and consequently, burns less efficiently.

Carbonaceous species

Carbonaceous aerosol, consisting of organic carbon and elemental carbon, is a by-

product of the incomplete combustion of both fossil fuels and biomass and is therefore a

ubiquitous component of anthropogenic aerosols. Elemental carbon (EC) is produced

especially under intense flaming conditions, when the supply of oxygen is deficient or

when parts of a flame are quenched before the oxidation of carbon radicals is complete.

Under smoldering conditions, on the other hand, little EC is produced, and the

carbonaceous fraction of the aerosol consists predominantly of tarry materials. 8 Daily

variation of OC and EC concentrations and OC/EC ratios in fine particles observed during

the fall 2002 intensive period are shown in Figure 6. OC concentrations in the fine mode

increased more drastically than levels of EC during the biomass burning periods, resulting

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in higher OC/EC ratios. As summarized in Table 4, average OC and EC concentrations in

fine mode during barley straw (BBB) and rice straw (BBR) burning periods were 21.6, 2.9

and 20.5, 2.6 µgm -3 , respectively. Both OC and EC concentrations were approximately

double those obtained during the background days (BG). During Asian dust events and

urban pollution days, the average OC and EC concentrations were 15.5, 2.8 and 9.9, 1.7

µgm -3 , respectively. Both OC and EC concentrations were approximately twice those

obtained during the background days (BG). During Asian dust events and urban pollution

days, the average OC and EC concentrations were 15.5, 2.8 and 9.9, 1.7 µgm -3 , respectively.

The average OC/EC ratios of 7.3 and 8.3 observed during the barley straw (BBB) and rice

straw (BBR) burning days were higher than levels measured on other days. It can be

concluded that both organic carbon and elemental carbon increased during biomass burning

periods, with OC being present in a higher proportion. The OC/EC ratio observed

previously in fall at an urban site in Gwangju 14 was much lower than that observed during

biomass burning events in this study. Park et al. (2002) reported an annual average OC/EC

ratio of 7.2 in the Siwha industrial area in Korea and 1.6 in June at an urban site in

Gwangju. 18,19 The OC/EC ratios during the urban pollution period (UP) of this study ranged

from 4.8 to 7.0. The percentage of organic carbon to total fine mass was 16.7, 43.5, and

52.0% for biomass burning of barley straw (BBB), rice straw (BBR) and urban pollution

(UP), respectively. High OC concentrations observed in this study reflect that a large

amount of OC was emitted in the smoldering agricultural biomass burning in Gwangju,

Korea.

Differences in chemical composition between two types of biomass burning aerosols

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Figure 7 shows the composition of biomass burning aerosols from two different

vegetation types: barley straw and rice straw. In the case of post-harvest biomass burning of

rice straw, a major component was organic carbon, which made up 44% of the total fine

mass. Mass fractions of the major ionic species sulfate, nitrate and ammonium were higher

during the post-harvest biomass burning of barley straw than those measured during the fall

intensive sampling during rice straw burning, while the organic carbon fraction decreased.

It can be concluded that these differences were caused by stagnant atmospheric conditions

and the contribution of fertilizers used for barley farming in the region. The fertilizers used

for barley farming contain high amounts of nitrogenous compounds. Figure 8 summarizes

the composition of PM2.5 for four different categories: background (BG), urban pollution

(UP), biomass burning (BBR), and biomass burning plus Asian dust (BBR+AD). The

dominant component of fine aerosol was OC during the biomass burning events, soil and

others during the Asian dust event, OC during urban pollution days. As expected, soil and

others fractions increased greatly during the Asian dust events in comparison to other

events.

Principal component analysis (PCA) has been used to identify the factors

influencing the variance of chemical constituents of PM2.5. The procedure was conducted

with the exclusion of the Asian dust samples among the total samples. After Varimax

rotation, four factors were found to explain 89.2% of the total variance as summarized in

Table 5. The first factor accounting for 40.8% of the total variance was associated with Ca 2+ ,

Al, Ca, Fe, K, Mg, Na, Ti, V, Mn, Sr, Zr, and Ba. This factor could be interpreted as

representing the influences of soil and the Earth’s crust. The second factor accounting for

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27.4% of the variance in the whole data set was primarily correlated with SO4 2+ , Na + , NH4 + ,

K + , EC, K, S, Zn, As, Cd, Pb and wind speed. This factor could be interpreted as resulting

from the effects of biomass burning of post-harvest waste. The third factor accounting for

12.5% of the total was Cl - , NO3 - , OC, EC, and Sb. This factor could be interpreted as

resulting from the influences of the combustion of fossil fuel and metallurgical processes.

The fourth factor accounting for 8.5% of the total variance was correlated primarily with

Cu, Sb, and relative humidity. This factor could be interpreted as representing the effects of

exhaust emissions from both gasoline and diesel-fuelled road vehicles. 20-22

The South Africa Fire-Atmosphere Research Initiative (SAFARI) 5 reported that BC,

P, K, Ca, Mn, Zn, Sr and I were the dominant elements in the coarse fraction, while BC, K,

Cu, Zn, Sb, Rb, Cs and Pb were the dominant elements in the fine fraction. Biogenic and

biomass burning aerosol particles in the Amazon Basin dominated the fine mode mass

concentration, and included the presence of K, P, S, Cl, Zn and Br. 23 Figure 9 presents

median enrichment factors calculated relative to the average crustal rock, with Al as the

reference element, in each events for fine and coarse mode aerosols. 24 According to these

results, K, S, Cu, Zn and Pb in fine mode and Cr, Cu, Zn and Pb in coarse mode were

enriched during biomass burning events in comparison to levels obtained during

background days. However, the median EFs for the elements Ca, Fe, Mg, Na and Ti in the

fine mode and Ca, Fe, K, Mg, Ti, Mn and Ba in the coarse mode approximated a value of 1.

This indicates that these elements were not enriched in the aerosol particles during the

biomass burning days, and higher EFs with large variation are associated with the elements

S, Cu, Zn and Pb during these periods. These elements depend on source location and

13


source strength. It can be concluded that the biomass burning of rice straw in Gwangju is a

major source of K, S, Cu, Zn and Pb in the fine mode, and S, Cr, Cu, Zn and Pb in the

coarse mode. During the Asian dust storm, the typical mineral dust elements Ca, Fe, K, Mg,

Na, Ti and Mn were highly enriched in the fine and coarse mode, while the elements Ni, Cu,

Zn and Pb, which are attributed to a variety of anthropogenic sources, were also highly

enriched.

Table 6 summarizes the differences in chemical composition of aerosol samples

observed in this study and those obtained from other biomass burning events in Brazil, the

African savanna, and tropical forests. The K/BC ratio in this study shows a similarity with

the ratio observed with a flaming type biomass burning of Amazon basin region, and the

K + /NO3 - ratio is similar to that measured for a flaming type biomass burning of a tropical

forest. However, these results showed that the signature of biomass burning in Northeast

Asia displayed an overall difference when compared to other places, such as the Amazon,

Europe and African regions. It can be concluded that this overall difference was caused by

the high content of semi-arid vegetation at the sampling site region.

CONCLUSIONS

In order to investigate the chemical characteristics of biomass burning aerosols

from the burning of post-harvest agricultural waste, ambient aerosol samples were collected

in Gwangju, Korea on June 4-14, 2001 and October 9- November 14, 2002. Significant

increases in fine aerosol mass were observed during the biomass burning events, especially

14


with respect to organic carbon components. The average mass concentration in the fine and

coarse mode was 129.6 µgm -3 and 24.2 µgm -3 in June 2001, and 47.1 µgm -3 and 33.2 µgm -3

in October to November 2002, respectively. In the soluble ionic aerosol fraction, Cl - , NO3 - ,

and SO4 2- were abundant anions, and NH4 + and K + concentrations dominated the cation

component of the fine aerosol during the biomass burning periods. Higher OC/EC ratios

were observed during the biomass burning events, attributable to the higher levels of OC.

The major component of samples obtained during the post-harvest biomass burning of rice,

was organic carbon, which represented consisting of 44% of the total fine mass. In

comparison to samples obtained during the post-harvest biomass burning of rice, fractions

of sulfate, nitrate and ammonium increased during the post-harvest biomass burning of

barley, while the carbon fraction decreased. Factor analysis revealed four factors that

accounted for 89.2% of the total variance. One factor represents the influence from soil; a

second factor represents possible effects from biomass burning; a third factor represents the

influence from combustion of fossil fuel and metallurgical processes, while a fourth factor

represents the influence of exhaust emissions from both gasoline and diesel-fuelled road

vehicles. This study showed that the signature of biomass burning in the Northeast Asia

was quite different from that observed in the Amazon, Europe and African regions.

Enrichment of the fine particles was remarkable, and the increased amount of aerosols,

resulting from biomass burning after harvesting causes adverse effects on local air quality

and human health. The results from this study can be used to evaluate the impact of

biomass burning aerosols over Korea, and to establish effective control strategies to lessen

the deleterious impact such phenomena have on the environment and human health.

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ACKNOWLEDGEMETS

This work was supported in part by the Korea Science and Engineering Foundation

(KOSEF) through the Advanced Environmental Monitoring Research Center (ADEMRC)

at Kwangju Institute of Science and Technology and the Brain Korea 21 Project, Ministry

of Education and Human Resources Development (MOE) Korea.

REFERENCES

1. Crutzen, P.J.; Andreae, M.O. Biomass burning in the tropics: Impact on atmospheric

chemistry and biogeochemical cycles; Science 1990, 250, 1669-1678.

2. Andreae, M.O.; Atlas, E.; Harris, G.W.; Helas, G.; Kock, A.; Koppmann, R.; Maenhaut,

W.; Mano, S.; Pollock, W.H.; Rudolph, J.; Scharffe, D.; Schebeske, G.; Welling, M. Metyl

halie emissions from savanna fires in southern Africa; J. Geophys. Res. 1996, 101, 23603-

23613.

3. Andreae, M.O.; Anderson, B.E., Blake, D.R.; Bradshaw, J.D.; Collins, J.E.; Gregory,

G..L.; Sachse, G.W.; Shipham, M.C. Influence of plumes from biomass burning on

atmospheric chemistry over the equatorial and tropical South Atlantic during CITE 3; J.

Geophys. Res. 1994, 99, 12793-12808.

4. Holben, B.N.; Setzer, A.; Eck, T.F.; Pereira, A.; Slutsker, I. Effect of dry-season biomass

burning on Amazon basin aerosol concentrations and optical properties, 1992-1994; J.

16


Geophys. Res. 1996, 101, 19465-19481.

5. Maenhaut, W.; Salma, I.; Cafmeyer, J.; Annegarn, H.J.; Andreae, M.O. Regional

atmospheric aerosol composition and sources in the eastern Transvaal, South Africa, and

Impact of biomass burning; J. Geophys. Res. 1996, 101, 23631-23650.

6. Anderson, B.E.; Grant, W.B.; Gregory, G.L.; Browell, E.V.; Collins, J.E.; Sachse, G.W.;

Bagwell, D.R.; Hudgins, C.H.; Blake, D.R.; Blake, N.J. Aerosols from biomass burning

over the tropical South Atlantic region: Distributions and impacts; J. Geophys. Res. 1996,

101, 24117-24137.

7. Fang, M.; Zheng, M.; Wang, F.; To, K.L.; Jaafar, A.B.; Tong, S.L. The solvent-

extractable organic compounds in the Indonesia biomass burning aerosols-characterization

studies; Atmos. Environ. 1999, 33, 783-795.

8. Andreae, M.O.; Andreae T.W.; Annegarn, H.; Beer, J.; Cachier, H.; Canut, P.; Elbert, W.;

Maenhaut, W.; Salma, I.; Wienhold, F.G.; Zenker, T. Airborne studies of aerosol emissions

from savanna fires in southern Africa: 2. Aerosol chemical composition; J. Geophys. Res.

1998, 103, 32119-32128.

9. Yamasoe, M.A.; Artaxo, P.; Miguel, A.H.; Allen, A.G. Chemical composition of aerosol

particles from direct emissions of vegetation fires in the Amazon Basin: water-soluble

species and trace elements; Atmos. Environ. 2000, 34, 1641-1653.

10. Intergovernmental Panel on Climate Change (IPCC), Climate change 2001: The

scientific Basis, edited by Houghton, J.T. et al.; Cambridge Univ. Press, New York, 2001,

36-46.

11. Ramanathan, V.; Crutzen, P.J.; Lelieveld, J.; Mitra, A.P.; Althausen, D.; Anderson, J.;

17


Andreae, M.O.; Cantrell, W.; Cass, G.R.; Chung, C.E.; Clarke, A.D.; Coakley, J.A.; Collins,

W.D.; Jayaraman, W.C.; Kiehl, J.T.; Krishnamurti, T.N.; Lubin, D.; McFarquhar, G.;

Novakov, T.; Ogren, J.A.; Podgorny, I.A.; Prather, K.; Priestly, K.; Prospero, J.M.; Quinn,

P.K.; Rajeev, K.; Rasch, P.; Rupert, S.; Sadourny, R.; Satheesh, S.K.; Shaw, G.E.; Sheridan,

P.; Valero, F.P.J. The Indian Ocean Experiment: An integrated analysis of the climate

forcing and effects of the Great Indo-Asian Haze; J. Geogphy. Res. 2001, 106, 28371-

28398.

12. Fung, K.; Chow, J.C.; Watson, J.G. Evaluation of OC/EC Speciation by Thermal

Manganese Dioxide Oxidation and the IMPROVE Method; J. Air & Waste Manage. Assoc.

2002, 1333-1341.

13. HYSPLIT4 (Hybrid Single-Particle Lagrangian Integrated Trajectory) Model National

Oceanic and Atmospheric Administration Air Resources Laboratory: Silver Spring, MD,

1997; http://www.arl.gov/ready/hysplit4.html.

14. Kim, K.W.; Kim, Y.J.; Oh, S.J. Visibility impairment during Yellow Sand periods in the

urban atmosphere of Kwangju, Korea; Etmos. Environ. 2001, 35, 5157-5167.

15. NAAQS, National Ambient Air Quality Standards, available at

http://www.epa.gov/airs/criteria.html.

16. Andreae, M.O. Soot carbon and excess fine potassium: Long-range transport of

combustion-derived aerosols; Science 1983, 220, 1148-1151.

17. Cachier, H.; Ducret, J.; Bremond, M.P.; Yoboue, V.; Lacaux, J.P.; Gaudichet, A.; Baudet,

J. Biomass burning in a savanna region of the Ivory Coast, in Global Biomass Burning:

Atmospheric, Climatic and Biospheric Implications, edited by Levine, J.S.; MIT press,

18


Cambridge, Mass., 1991.

18. Park, S.S.; Kim, Y.J.; Fung, K. Characterization of PM2.5 carbonaceous aerosol in the

Sihwa industrial area, South Korea; Atmos. Environ. 2001, 35, 657-665.

19. Park, S.S.; Kim, Y.J.; Fung, K. PM2.5 carbon measurements in two urban areas: Seoul

and Kwangju, Korea; Atmos. Environ. 2002, 36, 1287-1297.

20. Pacyna, J.M. Toxic Metals in the Atmosphere, edited by Nriagu, J.O.; Davison, C.I.;

Wiley, New York, 1986.

21. Pacyna, J.M. Source inventories for atmospheric trace metals, edited by Harrison, R.M.;

van Grieken, R.E.; Atmospheric Particles, IUPAC Series on Analytical and Physical

Chemistry of Environmental Systems, Vol 5, Willey, Chichester, UK, pp 385-423.

22. Allen, A.G.; Nemitz, E.; Shi, J.P.; Harrison, R.M.; Greenwood, J.C. Size distributions of

trace metals in atmospheric aerosols in the United Kingdom; Atmos. Environ. 2001, 35,

4581-4591.

23. Artaxo, P.; Gerab, F.; Yamasoe, M.A.; Martins, J.V. Fine mode aerosol composition at

three long-term atmospheric monitoring sites in the Amazon Basin; J. Geophys. Res. 1994,

99, 22857-22868.

24. Mason, B. Principles of Geochemistry; John Wiley, New York, 1966.

25. Ezcurra, A.; Zarate, I.O.; Dhin, P.V.; Lacaux, J.P. Cereal waste burning pollution

observed in the town of Vitoria (northern Spain); Atmos. Environ. 2001, 35, 1377-1386.

26. Ferck, R.J.; Reid, J.S.; Hobbs, P.V. Emission factors of hydrocarbons, halocarbons,

trace gases and particles from biomass burning in Brazil; J. Geophys. Res. 1998, 103,

32107-32118.

19


List of Tables

Table 1. Chemical composition of fine and coarse mode aerosol measured in Gwangju,

Korea.

Table 2. Average mass concentrations of atmospheric particulate matters in Gwangju,

Korea.

Table 3. Average concentration of ionic species and soil measured during the intensive

periods.

Table 4. Average concentrations of PM2.5 carbonaceous species and OC/EC ratio.

Table 5. Factor pattern for VARIMAX-rotated factor loadings matrix from PM2.5 chemical

and meteorological data obtained October 8 - November 14 2002 in Gwangju, Korea.

Table 6. Differences in chemical composition among the different types of biomass

burning aerosol.

List of Figures

Figure 1. Temporal variation of PM10 mass concentration in Gwangju, Korea in 2001; A :

Asian dust storm period, B : Biomass burning of barley straw, C : Biomass burning of rice

straw.

Figure 2. Location of the sampling site of biomass burning aerosol.

Figure 3. Variations of aerosol mass concentration in the fine and coarse modes measured

in Gwangju, Korea in 2001 and 2002.

Figure 4. Three-day back-ward trajectories of air mass reaching the sampling site;

atmospheric stagnation conditions on 10 June 2001 (a) and 12 October 2002 (b),

20


northwesterly wind condition on 30 October 2002 (c), and Asian dust event day of 12

November 2002 (d).

Figure 5. Average aerosol mass concentration in fine and coarse modes for four different

categories during the intensive sampling period of 2002 in Gwangju, Korea; BG :

Background, UP : Urban pollution, BBR : Biomass burning of post-harvest of rice, and

BBR+AD : Biomass burning of post-harvest of rice plus Asian dust storm.

Figure 6. Variation of (a) concentrations of PM2.5 organic carbon and elemental carbon, and

(b) OC/EC ratio during the intensive period.

Figure 7. Comparison of PM2.5 composition for two different type of biomass burning; (a)

barley straw burning in 2001, and (b) rice straw burning in 2002.

Figure 8. Comparison of PM2.5 composition measured in Gwangju in the fall of 2002 for

four different categories; (a) non event days (BG), (b) urban pollution days (UP), (c)

biomass burning of rice straw (BBR), and (d) biomass burning plus Asian dust (BBR+AD).

Figure 9. Median crustal enrichment factors (EFs) for (a) fine and (b) coarse mode aerosol

measured in Gwangu in the fall of 2002; BG : Background, UP : Urban pollution, BBR :

Biomass burning of rice straw, BBR+AD : Biomass burning of rice straw plus Asian dust

storm.

21


Implications

Ionic, carbonaceous, and elemental species of post-harvest biomass burning aerosols were

analyzed to characterize their chemical composition and evaluate their impact on air quality

at Gwangju, Korea. Organic carbon increased greatly during the biomass burning events,

resulting in high OC/EC ratios. The results showed that particulate air quality in the

Gwangju area was greatly influenced by post-harvest agricultural biomass burning

activities during late spring and late fall. The results from this study can be used to evaluate

the impact of biomass burning aerosols over Korea, and to establish effective control

strategies to lessen the deleterious impact such phenomena have on the environment and

human health.

About the Authors

Seong Y. Ryu (andy@kjist.ac.kr), Jeong E. Kim (jekim@kjist.ac.kr), and Zhuanshi H.

(hzs@ademrc.kjist.ac.kr) are Ph. D. students in the Department of Environmental Science

and Engineering, Kwnagju Institute of Science and Technology (KJIST), 1 Oryong-dong,

Buk-gu, Gwnagju, Korea. Dr. Young J. Kim (yjkim@kjist.ac.kr) is a professor in the

Department of Environmental Science and Engineering, Kwnagju Institute of Science and

Technology (KJIST) and the director of the Advanced Environmental Monitoring Research

Center, which is supported by Korea Science and Engineering Foundation (KOSEF). Dr.

Gong U. Kang (gukang@wkhc.ac.kr) is an assistant professor in the Department of

Environmental Science, Wonkwang Health Science College, Iksan, Korea.

22


Table 1. Chemical composition of fine and coarse mode measured in Gwangju, Korea.

Fine mode (µgm -3 Year Date

Mass EC

)

OC SO4 2- NO3 - Cl - NH4 + K +

06/04 N 151.4 4.36 39.64 NM NM NM NM NM

Remarks

BBB *

06/05 D 157.8 NM NM 3.12 5.49 2.08 3.49 2.23 BBB *

06/05 N 104.6 2.80 17.45 15.95 23.41 3.02 10.77 4.89 BBB *

06/06 D 108.9 NM NM 17.66 12.23 1.83 8.55 4.20 BBB *

06/06 N 94.5 2.51 17.22 10.71 9.31 2.91 7.16 3.14 BBB *

06/07 D 100.2 NM NM 16.68 3.90 1.82 6.25 4.53 BBB *

06/07 N 146.0 2.47 18.78 20.30 17.74 3.82 10.69 4.97 BBB *

06/08 D 157.5 2.99 19.35 NM NM NM NM NM BBB *

06/08 N 146.4 NM NM 30.24 27.33 4.85 13.95 4.89 BBB *

06/09 A 143.1 2.69 21.80 38.21 22.48 6.74 14.52 8.58 BBB *

06/11 D 132.9 NM NM 34.80 15.44 1.20 12.84 2.00 BBB *

06/11 N 96.2 NM NM 21.84 15.13 1.65 10.65 1.15 BBB *

2001

06/12 A 144.8 2.60 16.72 46.92 39.77 2.00 17.92 5.51 BBB

06/15 A 35.8 1.01 5.89 6.55 8.74 1.16 6.05 0.47 BG

10/08 A 21.0 0.77 7.41 1.73 1.65 0.49 1.18 0.16 BG

10/09 D 18.8 0.51 7.32 2.17 2.99 0.38 1.55 0.14 BG

10/09 N 21.8 1.68 10.22 2.67 3.80 0.79 2.11 0.20 BG

10/10 D 22.5 1.94 9.58 0.81 1.65 0.43 0.65 0.08 BG

10/10 N 28.2 2.00 11.00 2.92 2.54 1.37 2.04 0.25 BG

10/11 D - 2.30 16.87 3.42 4.45 0.78 2.22 0.23 BG

10/11 N - 1.22 6.45 1.71 1.49 0.73 1.03 0.11 BG

10/12 D 19.3 1.46 8.62 4.57 2.88 0.70 1.96 0.16 UP *

10/12 N 29.2 1.90 12.12 5.35 2.21 1.48 2.48 0.28 UP *

10/13 A 33.0 1.51 7.14 11.02 4.04 0.75 3.45 0.73 UP *

10/14 D 39.7 1.60 11.96 8.18 3.64 0.81 3.03 0.74 UP *

10/14 N 27.9 1.90 9.53 3.69 1.91 1.04 1.63 0.50 UP *

2002

10/23 A 30.7 2.05 16.36 2.02 1.88 0.97 1.35 0.29 BB

10/25 D 72.7 3.19 27.70 8.77 2.22 1.08 3.13 0.98 BB

10/25 N 77.3 4.42 32.47 6.28 4.25 2.36 3.83 0.90 BB

10/26 A 10.2 0.56 2.44 3.08 0.36 0.19 1.12 0.09 BG

10/27 A 11.9 0.46 2.97 2.25 0.39 0.27 0.84 0.08 BG

10/28 A 12.2 1.52 4.52 1.86 0.71 0.59 0.99 0.09 BG

10/29 D 17.6 1.17 7.71 2.60 1.24 0.74 1.12 0.19 BG

10/29 N 30.9 1.99 12.40 2.65 2.87 1.25 2.07 0.24 BG

10/30 D 34.0 2.09 17.14 1.96 3.54 0.76 1.84 0.31 BB

10/30 N 70.2 3.52 32.72 2.39 7.41 2.15 3.53 0.53 BB

10/31 D 49.7 1.55 27.21 2.51 3.16 0.75 1.84 0.10 BB

10/31 N 38.1 1.38 13.20 4.09 5.54 0.55 3.33 0.32 BB

11/01 D 12.3 0.97 5.74 2.70 0.57 0.33 1.04 0.14 BG

11/01 N 9.5 0.30 2.81 1.76 0.63 0.42 0.81 0.09 BG

11/02 A 20.4 0.85 4.35 3.04 1.47 1.00 1.73 0.19 BG

11/05 A 24.4 2.51 10.05 3.92 2.15 1.76 2.73 0.34 BB

11/06 A - - - 8.34 4.47 0.97 3.87 0.60 BB

11/11 D 82.3 4.57 20.16 16.01 6.77 1.29 6.55 1.83 BBR+AD

11/11 N 125.5 3.32 11.65 8.06 3.49 1.00 2.76 1.39 BBR+AD

11/12 D 52.1 1.57 21.35 1.79 1.44 1.27 0.87 0.43 BBR+AD

11/12 N 21.9 1.54 8.79 1.36 1.39 0.55 1.15 0.20 BBR+AD

11/13 D 18.3 1.18 5.79 2.96 0.95 0.72 1.44 0.22 BG

23


11/13 N 21.9 1.98 7.97 2.98 1.57 0.92 1.76 0.17 BG

11/14 D 40.4 3.29 16.72 3.95 2.53 2.39 2.90 0.56 BB

11/14 N 33.7 2.29 11.38 4.47 2.93 1.69 2.71 0.50 BB

Coarse mode (µgm -3 Year Date

Mass EC

)

OC SO4 2- NO3 - Cl - NH4 + K +

06/04 N 30.2 NM NM - - - - -

Remarks

BBB *

06/05 D 38.7 NM NM 0.20 0.75 0.40 0.28 0.23 BBB *

06/05 N 16.7 NM NM 7.26 11.54 1.41 2.32 2.04 BBB *

06/06 D 26.4 NM NM 1.35 1.01 0.26 0.15 0.42 BBB *

06/06 N 22.6 NM NM 5.27 6.54 1.57 1.78 1.45 BBB *

06/07 D 35.4 NM NM 1.63 2.68 0.33 0.49 0.47 BBB *

06/07 N 24.4 NM NM 9.28 10.65 1.73 2.52 2.02 BBB *

06/08 D 21.2 NM NM - - - - - BBB *

06/08 N 25.8 NM NM 2.44 3.72 0.49 0.53 0.39 BBB *

06/09 A 15.6 NM NM 15.91 9.42 - 2.71 3.37 BBB *

06/11 D 12.1 NM NM 2.27 - 0.08 0.15 0.22 BBB *

06/11 N 18.1 NM NM 1.97 3.11 0.33 0.54 0.15 BBB *

2001

06/12 A 27.6 NM NM 18.45 18.67 1.72 3.30 2.07 BBB

06/15 A 9.3 NM NM 2.75 5.55 0.83 1.01 0.30 BG

10/08 A 22.8 0.81 6.35 NM NM NM NM NM BG

10/09 D 19.3 0.80 6.72 NM NM NM NM NM BG

10/09 N 44.0 1.69 6.80 NM NM NM NM NM BG

10/10 D 47.9 1.59 7.91 NM NM NM NM NM BG

10/10 N 50.7 2.53 8.53 NM NM NM NM NM BG

10/11 D - 0.83 0.18 NM NM NM NM NM BG

10/11 N - 2.71 10.95 NM NM NM NM NM BG

10/12 D 36.2 1.25 4.63 NM NM NM NM NM UP *

10/12 N 57.1 1.89 8.88 NM NM NM NM NM UP *

10/13 A 50.7 1.03 3.98 NM NM NM NM NM UP *

10/14 D 84.2 2.08 6.96 NM NM NM NM NM UP *

10/14 N - - - NM NM NM NM NM UP *

2002

10/23 A 21.0 0.24 1.53 0.17 0.41 0.32 0.11 0.09 BB

10/25 D 79.1 0.82 1.91 2.42 4.12 0.87 0.40 0.04 BB

10/25 N 47.4 0.86 1.18 1.43 2.02 0.73 0.37 0.16 BB

10/26 A 5.9 - - 0.26 0.46 0.85 0.03 0.04 BG

10/27 A 8.5 0.10 0.03 0.33 0.38 1.35 0.07 0.04 BG

10/28 A 9.0 - - 0.17 0.28 0.68 0.04 0.04 BG

10/29 D 19.2 - - 0.22 0.67 1.03 0.07 0.04 BG

10/29 N 6.8 0.69 0.19 0.26 0.87 0.72 0.21 0.07 BG

10/30 D 26.8 0.85 0.74 0.20 0.62 0.63 0.06 0.05 BB

10/30 N 17.9 0.53 0.23 0.20 0.71 0.29 0.13 0.08 BB

10/31 D 21.4 0.31 - 0.22 1.17 0.59 0.26 0.09 BB

10/31 N 28.2 0.17 0.18 0.45 1.46 0.69 0.25 0.07 BB

11/01 D 18.2 - - 0.41 0.63 1.18 0.10 0.07 BG

11/01 N 13.2 0.10 - 0.30 0.53 1.07 0.08 0.01 BG

11/02 A 8.9 0.61 2.49 0.27 0.48 0.46 0.15 0.05 BG

11/05 A 14.9 0.42 - 0.25 1.02 0.52 0.11 0.06 BB

11/06 A - - - 0.62 2.88 0.28 0.36 0.08 BB

11/11 D 34.5 0.44 1.02 1.51 5.86 1.58 1.04 0.17 BBR+AD

11/11 N 341.4 1.92 4.51 4.62 6.55 4.07 0.99 0.60 BBR+AD

24


11/12 D 92.9 0.83 0.97 1.27 1.11 2.27 0.33 0.17 BBR+AD

11/12 N 61.5 0.62 1.98 0.56 0.79 0.75 0.18 0.06 BBR+AD

11/13 D 19.5 - 0.80 0.37 0.94 0.78 0.15 0.07 BG

11/13 N 20.2 - 1.52 0.29 0.69 0.43 0.15 0.05 BG

11/14 D 49.7 0.28 2.62 0.51 2.09 0.78 0.29 0.07 BB

11/14 N 25.7 - 0.77 0.42 1.93 1.01 0.33 0.06 BB

Note: * : stagnation phenomena, D : Day, N : Night, A : All (24hr sampling)

BG : Background, UP : Urban pollution, BBB : Biomass burning of barley straw, BBR : Biomass

burning of rice straw, BBR+AD : Biomass burning of rice straw plus Asian dust

25


Table 2. Average mass concentrations of atmospheric particulate matters in Gwangju, Korea.

Intensive period Fine mass

(µgm -3 Coarse mass

)

(µgm -3 Remarks

)

06/04-06/15/01 129.6 ± 24.6 24.2 ± 7.7 This study, BBB *

10/08-11/14/02

18.5 ± 6.4 20.9 ± 14.9 This study, BG

29.8 ± 7.5 57.0 ± 20.1 This study, UP *

47.1 ± 19.4 33.2 ± 19.9 This study, BBR

70.4 ± 44.2 132.6 ± 141.2 This study, BBR+AD

1999 Summer 45.4 13.3 Kim et al. 2001 14

1999 Fall 41.1 11.9 Kim et al. 2001 14

1999 Winter 15.3 25.8 Kim et al. 2001 14

2000 Spring 15.3 44.5 Kim et al. 2001 14

2000 Asian dust 20.9 138.3 Kim et al. 2001 14

Note: Mean ± standard deviation, * : stagnation phenomena

BG : Background (10/08-11, 26-29, 11/01-02, 13, 2002), UP : Urban pollution (10/12-14, 2002),

BBB : Biomass burning of barley straw (6/04-14, 2001), BBR : Biomass burning of rice straw

(10/23, 25, 30-31, 11/05-06, 14, 2002), BBR+AD : Biomass burning of rice straw plus Asian dust

(11/11-12, 2002)

26


Table 3. Average concentration of ionic species and soil measured during the intensive periods.

BG

(µgm -3 BBB

)

(µgm -3 BBR

)

(µgm -3 BBR+AD

)

(µgm -3 Species

)

Fine Coarse Fine Coarse Fine Coarse Fine Coarse

Cl - 0.64 0.85 2.90 0.83 1.40 0.61 1.03 2.17

NO3 - 1.08 0.59 17.48 6.70 3.64 1.68 3.27 3.58

SO4 2- 2.59 0.29 23.31 6.24 4.43 0.63 6.80 1.99

nss SO4 2- 2.56 0.18 23.14 6.06 4.39 0.55 6.71 1.65

Na + 0.11 0.42 0.67 0.88 0.15 0.32 0.39 1.38

NH4 + 1.29 0.10 10.62 1.31 2.82 0.24 2.83 0.64

K + 0.15 0.05 4.19 1.09 0.49 0.08 0.96 0.25

Ca 2+ 0.06 0.22 0.23 0.88 0.10 0.60 0.37 3.25

Sea salt 0.28 1.04 1.67 1.78 0.38 0.80 0.97 3.45

Soil 0.76 1.53 - - 1.68 4.32 10.11 63.45

Note: BG : Background (10/08-11, 26-29, 11/01-02, 13, 2002), UP : Urban pollution (10/12-14,

2002), BBB : Biomass burning of barley straw (6/04-14, 2001), BBR : Biomass burning of rice

straw (10/23, 25, 30-31, 11/05-06, 14, 2002), BBR+AD : Biomass burning of rice straw plus Asian

dust (11/11-12, 2002), nss : non sea salt, Sea salt = 2.5[Na + ], Fine Soil = 2.20[Al] + 2.49[Si] +

1.63[Ca] + 2.42[Fe] + 1.94[Ti], Coarse mineral dust = 12.5[Al]

27


Table 4. Average concentrations of PM2.5 carbonaceous species and OC/EC ratio.

Events Organic carbon

(µgm -3 Elemental carbon

) (µgm -3 OC/EC Remarks

)

Background 1 7.4 ± 3.8 (40.0) 1.3 ± 0.6 (7.0) 5.7 ± 1.5 This study

Post-harvest of barely 2* 21.6 ± 8.2 (16.7) 2.9 ± 0.7 (2.2) 7.3 ± 1.1 This study

Post-harvest of rice 3 20.5 ± 8.7 (43.5) 2.6 ± 1.0 (5.5) 8.3 ± 3.8 This study

Urban pollution 4* 9.9 ± 2.2 (52.0) 1.7 ± 0.2 (9.4) 5.9 ± 1.1 This study

Asian dust + biomass burning 5 15.5 ± 6.2 (14.1) 2.8 ± 1.5 (2.4) 6.8 ± 4.6 This study

2000 June 7.6 4.9 1.6 Park et al. 2002 19

1999 Summer 11.1 3.8 2.9 Kim et al. 2001 14

1999 Fall 14.2 5.1 2.8 Kim et al. 2001 14

1999 Winter 5.0 1.1 4.5 Kim et al. 2001 14

2000 Spring 7.4 2.3 3.2 Kim et al. 2001 14

2000 Asian dust 6.4 2.2 2.9 Kim et al. 2001 14

Note: Mean ± standard deviation (% of total fine mass), * : Stagnation phenomena of atmosphere

were observed.

1 2 3 4

: 10/08-11, 26-29, 11/01-02, 13, 2002, : 6/4-15, 2001, : 10/23, 25, 30-31, 11/05-06, 14, 2002, :

10/12-14, 2002, 5 : 11/11-12, 2002

28


Table 5. Factor pattern for VARIMAX-rotated factor loadings matrix for PM2.5 chemical and

meteorological data obtained October 8 - November 14, 2002 in Gwangju, Korea.

Species Component

Communality

1 2 3 4

Cl - -0.162 -0.009 0.896 0.318 0.929

NO3 - -0.044 0.564 0.604 -0.081 0.691

SO4 2- 0.208 0.854 -0.029 -0.201 0.815

Na + 0.460 0.765 -0.185 -0.034 0.832

NH4 + -0.032 0.876 0.412 -0.034 0.940

K + 0.484 0.799 0.243 -0.053 0.935

Ca 2+ 0.867 0.090 -0.076 -0.327 0.873

OC -0.108 0.099 0.829 -0.368 0.844

EC 0.204 0.543 0.756 0.184 0.942

Al 0.988 0.041 -0.039 0.087 0.987

Ca 0.988 0.051 -0.035 0.021 0.981

Fe 0.990 0.084 -0.019 0.036 0.989

K 0.865 0.459 0.171 0.033 0.989

Mg 0.993 0.066 -0.001 0.031 0.991

Na 0.882 0.415 -0.062 0.166 0.981

S 0.331 0.886 0.151 -0.162 0.945

Ti 0.964 0.072 -0.070 0.195 0.977

V 0.971 0.130 -0.084 0.091 0.975

Mn 0.895 0.406 0.004 0.121 0.981

Ni -0.110 0.575 -0.204 -0.153 0.408

Cu -0.233 0.244 -0.062 0.595 0.471

Zn 0.242 0.932 0.056 0.204 0.972

As 0.325 0.845 0.325 0.152 0.948

Sr 0.967 0.235 -0.011 0.069 0.994

Zr 0.950 0.233 -0.015 0.146 0.978

Cd 0.405 0.825 0.219 0.277 0.970

Sb -0.161 0.069 0.886 0.319 0.918

Ba 0.958 0.249 0.005 0.101 0.991

Pb 0.215 0.933 0.127 0.197 0.973

Temp. -0.318 -0.058 -0.155 -0.834 0.825

RH 0.299 -0.282 0.184 0.669 0.650

Wind Speed -0.287 0.521 -0.402 -0.561 0.831

Variance (%) 40.8 27.4 12.5 8.5 89.2

Note: Loadings > 0.6 are in bold, and > 0.3 are underlined.

29


Table 6. Differences in chemical composition among the different types of biomass burning aerosol.

Region Type K + /NO3 - K + /SO4 2- K/BC Cl - /K + OC/EC Remarks

Northeast Asia

(Agricultural waste)

Europe (Spain)

(Cereal waste)

Africa

(Savanna)

Tropical forest

Brazil

(Amazon basin)

Rice straw 0.11 0.11 0.24 0.71 8.3 This study, BBR

Barley straw 0.33 0.24 - 0.75 7.3 This study, BBB

1.3 0.41 - 0.62 - Ezcurra et al. (2001) 25

Airborne 0.97 0.61 0.62 3.89 2.7 Andreae et al. (1998) 8

Flaming - - 0.20 - -

Smoldering - - 0.17 - -

Flaming 0.15 1.13 0.11 0.38 -

Smoldering 0.3 0.98 0.10 0.50 -

30

Maenhaut et al. (1996) 5

Yamasoe et al. (2000) 9

- - - 0.60 - - Ferek et al. (1998) 26

Flaming 4.84 4.17 0.24 0.73 -

Smoldering 3.71 3.94 0.20 0.77 -

Note: BBR : Biomass burning of rice straw, BBB : Biomass burning of barley straw

Yamasoe et al. (2000) 9

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