간행물
한국환경과학회지 KCI 등재 Journal of Environmental Science International
- 발행기관 한국환경과학회
- 자료유형 학술지
- 간기 월간
- ISSN 1225-4517 (Print)2287-3503 (Online)
- 수록기간 1992 ~ 2023
- 주제분류 자연과학 > 자연과학일반 자연과학 분류의 다른 간행물
- 십진분류KDC 539DDC 628
권호리스트/논문검색
제12권 제7호 (2003년 7월) 16건
1.
2003.07
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The purpose of this study is to evaluate and to predict of eutrophication in lakes by using Vollenweider- OECD model and total phosphorus concentration and inflow rate which were measurded in 1993～2001. The results of study were as follows.
The annual total phosphorus loading from the watershed was calculated to be 55～195tP/yr at lake Soyang, 221～466tP/yr at lake Taechong, 123～278tP/yr at lake Andong, 57～109tP/yr at lake Seomjin. These are discharged, for the most parts, from population and fishfarm facility.
TP loading on the surface area at lake Soyang was 3.01gP/㎡/yr, 2.82gP/㎡/yr, 2.84gP/㎡/yr, 3.03gP/㎡/yr, 2.34gP/㎡/yr, 1.78gP/㎡/yr, 0.91gP/㎡/yr, 0.89gP/㎡/yr, 0.86gP/㎡/yr, lake Taechong was 6.71gP/㎡/yr, 7.25gP/㎡/yr, 7.24gP/㎡/yr, 6.53gP/㎡/yr, 6.50gP/㎡/yr, 7.06gP/㎡/yr, 7.04gP/㎡/yr, 4.05gP/㎡/yr, 3.44gP/㎡/yr and TP loading on the surface area of lake Andong, lake Soemjin were 5.39gP/㎡/yr, 4.47gP/㎡/yr, 4.56gP/㎡/yr, 4.45gP/㎡/yr, 3.33gP/㎡/yr, 2.38gP/㎡/yr, 2.53gP/㎡/yr, 2.46gP/㎡/yr, 2.54gP/㎡/yr, 4.09gP/㎡/yr, 4.10gP/㎡/yr, 3.98gP/㎡/yr, 3.73gP/㎡/yr, 2.80gP/㎡/yr, 3.46gP/㎡/yr, 3.22gP/㎡/yr, 2.19gP/㎡/yr, 2.13gP/㎡/yr respectively.
The tropic states of four lakes can be assessed as eutrophy because phosphorus loading exceeds the critical phosphorus loading by Vollenweider-OECD model.
2.
2003.07
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Through data analysis using the meteorological data during 40 years(1961～2000) for 2 stations(Daegu and Chupungnyong), we studied the present condition and long-term trends in urban climatic environments of Daegu.
It was found that there was about 1.5℃ rise in annual mean temperature of Daegu from 1961 to 2000. On the other hand, that of Chupungnyung was not more than 0.4℃ for the same period. The regional disparity in temperature changes has been caused by the difference of urban effects on climate between two regions. In particular, the urban warming appears more significant in winter season. There was about 3℃ rise in annual mean daily minimum temperature of winter season(Dec.～Feb.) in Daegu. As the result, the number of winter days continuously decreased from 115 days(1961) to 75 days(2000).
The long-term trends of relative humidity were also studied to exame the effects of urbanization on climate in Daegu. It was found that there was about 7% decrease in relative humidity of Daegu during past 40 years(1961～2000). On the other side, the decrease of Chupungnyung was not more than 2% for the same period. The ong-term trends of the other climatic factors(fog days, tropical night days, etc) were also studied in this study.
3.
2003.07
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In mid-August 2002, under clear summer pressure patterns, we carried out an intensive meteorological observation to examine the warming effects due to artificial constructions in a large housing complex. We set an automatic weather system(AWS) at two places in a bare soil surface within a limited development district and an asphalt surface within a large apartment residence area, respectively. As a result of observation, it became clear that the difference of the surface air(ground) temperature between the bare soil surface and its peripheral asphalt area reached about 4℃(13℃) at the maximum from diurnal variation of surface temperatures on AWS data.
Through the heat balance analysis using measurement data, it became clear that the thermal conditions at two places are dependent on the properties of surface material. The latent heat flux over the bare soil surface reached to about 300, which is more than a half of net radiation during the daytime. On the other hand, it was nearly zero over the asphalt surface. Hence, the sensible heat flux over the asphalt surface was far more than that of the bare soil surface. The sensible heat flux over the asphalt surface showed about 20～30 during the night. It was released from asphalt surface which have far more heat capacity than that of bare soil surface.
4.
2003.07
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Studies on the Distribution of the Microalgae in the Tidal Flats of Gamami Beach, Young-Gwang, Korea
Distributional patterns of microalgae were studied in the tidal flats of Gamami Beach(Young-Gwang, Korea) from November 1999 to 2000 July. The tidal flats of Gamami Beach was composed mainly of sandy sediment. The concentrations of nutrients were low compared with other tidal flats. In the present study, 68 species of microalgal flora were identified. These were comprised of 25 species of benthic microalgae and 59 species of planktonic microalgae. Diatoms predominated the benthic microalgae with 96.0% of total species occurred. Dominant species were Amphora sp., Cocconeis sp., Coscinodiscus asteromphalus, Coscinodiscus sp., Nitzschia sigma var. intermedia, Nitzschia distans, Navicula spp., Paralia sulcata, Pleurosigma sp. Skeletonema coastatum, and Surirella sp. Among them, Amphora sp., Paralia sulcata, and species of Pleurosigma and Nitzschia were observed throughout the studied period. Planktonic microalgae of Gamami Beach was also predominated by diatoms. They occupied 88.1% of total planktonic microalgae. The density of microalgal population was higher in silty sediment than in sandy sediment. The population density of microalgae was higher in high tide zone than that in low tide zone. The density of the benthic microalgae in the surface layer of tidal flats showed increasing tendency for 2 hours after the beginning of ebb tide. On the contrary, benthic microalgal density of subsurface layer was decreased during the period. Concentrations of chlorophyll a from sediment and water were not synchronized during the study period. Therefore, the distributional patterns of the benthic microalgae and planktonic algae seemed not to be related. Chlorophyll a of water was highly related with the concentration of NH4-N, whereas, chlorophyll a of sediment was related with NO3-N concentration.
5.
2003.07
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This survey was carried out to assess important species of phytoplankton in the ocean and bay in Korea from 32 references. The number of important species assessed from 50 genera 116 species. Of them, Bacillariophycea (diatoms) 34 genera 89 speceis(76.6%), Dinophyceae(dinoflagellates) 11 genera 22 species(18.9%), Chrysophyceae 2 genera 2 species(1.7%), Cyanophycea(blue-green algae), Raphidophyceae, Euglenophyceae(euglenoids) 1 genera 1 species(0.9%) respectively. By ecological characters, the number of dominant species were 79 species including Actinoptychus seranius, 50 species including Coscinodiscus centralis were recorded as frequently apperaing species and 36 species including Cochlodinium polykrikoides were recorded as red-tide causative organism. Also, 11 species including Prorocentrum micans were surveyed as the indicator including all ecological characters.
6.
2003.07
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7.
2003.07
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The three-dimensional eco-hydrodynamic model was applied to estimate the physical process in terms of nutrients and net uptake(or regeneration) rate of nutrients in Kamak Bay for scenario analysis to find proper management plan. The estimation results of the physical process in terms of nutrients showed that transportation of nutrients is dominant in surface level while accumulation of nutrients is dominant in bottom level. In the case of dissolved inorganic nitrogen, the results showed that the net uptake rate was 0～60 mg/m2/day in surface level(0～3m), and the net regeneration rate was 0.0～10.0 mg/m2/day in middle level(3～6m) and above 10 mg/m2/day in bottom level(6m～below). In the case of dissolved inorganic phosphorus, the net uptake rate was 0.0～3.0 mg/m2/day in surface level, and the net regeneration rate was 0.5～1.5 mg/m2/day in middle level and 1.0～3.0 mg/m2/day in bottom level. These results indicates that net uptake and transport of nutrients are occurred predominantly at the surface level and the net generation and accumulation are dominant at bottom level. Therefore, it is important to consider the re-supplement of nutrients due to regeneration of bottom water.
8.
2003.07
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Butyltin compounds (BTs), namely tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MBT), were measured in surface sediments collected in 2001 inside Hallim Harbor where a lot of shipping occurs as one of major harbors of Jeju Island, in order to evaluate their distribution. BTs were detected in surface sediments of all stations and their concentrations were comparable to those in surface sediments of other sites of domestic and foreign countries. The main species among BTs was MBT, although there was a little difference with a survey site. No correlations were obtained between organic matter or particles size of surface sediments and total BTs, indicating that these factors did not affect on the distribution of BTs. It was estimated that more complex factors including BTs loads and surrounding sedimentary environments, affected on the distribution of BTs. The high correlations between BTs indicated that DBT and MBT were mainly degraded from TBT based on antifouling paints of vessel etc. and other sources, such as DBT and MBT, could be ignored. The butyltin degradation indexes ([DBT] + [MBT]/[TBT]) were in the range of 1.5～3.3 (mean 2.5), indicating that the parent compound, TBT, were inflowed into the surface sediments a long years ago and degraded.
9.
2003.07
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This study was conducted to design long and short forms of reliable and valid Likert-type scales to measure environmental attitudes of Korean junior high school students. 8 tests were applied to the construction of a 32-item long form and 8-item short form of the scale. Two scales were field tested on 469 respondents consisting of male and female students in urban and rural areas and students participating in environmental programs. The 32-item scale was revealed to be highly reliable, content and construct valid. Reliability and homogeneity of this scale were evidenced by 0.92 coefficient alpha and positive interitem correlation values ranging from 0.10 to 0.52. Factor analysis and known-group comparison showed the sufficient validity of long form scale. Reliability and validity of short form scale were also evidenced by good results of 8 test analyses. The long and short forms were strongly correlated, r-value of 0.90. Consequently, both long form and short form scales were evidenced very reliable and valid in measuring environmental attitudes of junior high school students in Korea. They can be useful for a variety of survey conditions and constraints and testing environmental attitude.
10.
2003.07
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The photodegradations of pyrene, chrysene and benzo[a]pyrene that were similar in structure among polycyclic aromatic hydrocarbons (PAHs) were investigated with a low-pressure mercury lamp(the wavelength of 253.7 nm and UV output of 1.35x10-3 J/s). The optimum concentrations of TiO2 and H2O2 on the photodegradation of pyrene, chrysene and benzo[a]pyrene were 1 g/L and 1.5 x 10-3 M, respectively. By these optimum concentrations, their rates increased with increasing the concentration of TiO2 and H2O2 because the amounts of OH radical formed increased, but for the higher concentrations than the optimum, their rates decreased with increasing those concentrations because the white turbidity phenomena occurs in case of TiO2 and H2O2 acts as an OH radical inhibitor. The photodegradation rates among the photodegradation processes such as UV, UV/TiO2, UV/H2O2, and UV/H2O2/TiO2 decreased in the following sequences: UV/H2O2/TiO2> UV/H2O2> UV/TiO2> UV.
11.
2003.07
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This study was conducted to reuse the rice straw ash as washing agent for oil contaminated soils. The results are summarized as follows. The physical characteristics of rice straw before and after burning were as follows ; In case of burning rice straw 1g, the rice straw ash was generated 0.14g and pH was changed neutrality into alkali(pH 10.9) and specific surface area was increased to five times and particle distribution was corresponded to fine silt(under 0.05㎜)
The physical charateristics of rice straw ash were Carbon 10.9%, Hydrogen 1.5%, Oxygen 23.4%, Nitrogen 5.2%, Sulfate 1.2% and chemical charateristics were Si 189.2ppm, Ca 10.2ppm, Mg 4.7ppm. Oil cleanup ratio by pH varation were about 40～50% of initial concentration of oil by pH 10～11. As the result of cleanup comparative experiment, the rice straw ash was about 20～30%, the tritonX-100 about 40～50% of washing efficiency, and then in the future it will be possibility of substitute washing agent.
12.
2003.07
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This study was carried out to get more operational characteristics of the sequencing batch biofilm reactors with media volume/reactor volume ratio of 15 %, 25 % and 35 %. Experiments were conducted to find the effects of the media packing ratio on organic matters and nutrients removal. Three laboratory scale reactors were fed with synthetic wastewater. During studies, the operation mode was fixed. The organic removal efficiency didn't show large difference among three reactor of different packing media ratios. However, from the study results, the optimum packing media ratios for biological nutrient removal was shown as 25%. The denitrifying PAOs could take up and store phosphate using nitrate as electron acceptor.
13.
2003.07
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This work aims the search of environmentally friendly pre-treatment technologies to develop chromate replacements for metal finishing industries due to its toxicological properties. Since the corrosion resistance of steel was strongly related to water permeation, galvanized steel sheets were treated with various hydrophobic silane compounds and water-suspended polymer solution. Also, plasma gas discharge was applied to modify the surface of a polymer coated-steel sheet to be hydrophobic. The surface hydrophobicity of materials was introduced by CF3H plasma exposure. The corrosion property before and after the plasma treatment was investigated in a slat spray tester with 3.5 wt.% NaCl at 35 ℃. The results showed that both silane/polymer double coatings and plasma treatment of the galvanized steel exhibited significant retardation of corrosion.
14.
2003.07
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The short-term version of Industrial Source Complex Model(ISCST3) was evaluated for estimating short-term concentrations using criteria pollutant(SO2, NO2, CO, PM10) data form emission inventory of Young Tong area in Suwon for the year 2002. The contribution of pollutant concentration from point, line, area sources was found 21.8, 76.5 and 1.6%. Statistical parameters, such as correlation coefficient, index of agreement(IA), normalized mean square error(NMSE) and fractional bias(FB) were calculated for each pollutants. The model performance were found good for PM10(82%) and NO2(69%), but poor for SO2(34%) and CO(13%).
15.
2003.07
서비스 종료(열람 제한)
Various kinds of zeolites, such as analcime (ANA), cancrinite (CAN), Na-P1 and sodalite octahydrate (SOD) could be synthesized from Hwangto by hydrothermal reaction in a high-pressure vessel. The adsorption characteristics of Cu(II) and Cd(II) by Hwangto and its synthetic zeolites were investigated using the chemical and electrochemical surface parameters of these adsorbents. The heavy metal adsorptivity among the adsorbents decreased in the following sequences: Na-P1>SOD>ANA>CAN>Hwangto. This sequence was the same with the values of surface site density (Ns) of these adsorbents and was correlated inversely with the values of pHpzc (pH of the point of zero charge) and the values of Ka2(int) (intrinsic surface deprotonation constant) of the adsorbents for synthetic zeolites, i.e., the adsorbents with higher values of Ns and with lower values of pHpzc and Ka2(int) for synthetic zeolites showed higher heavy metal adsorptivity. With increasing pH, the heavy metal adsorptivity increased greatly between pHpzc and pH 6 or 7 because of the steep increase of negatively charged sites for synthetic zeolites, but for Hwangto, it increased broadly because of slow increase of negatively charged sites based on its lower surface sites.
연구노트
16.
2003.07
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The emission of volatile organic compounds (VOCs) generated from painting and coating processes is a worldwide problem as contributing factors to the development of photochemical smog and other environmental problems. Common methods of reducing VOC emissions are adsorption on activated carbon, membrane separation, absorption, incineration, or catalytic oxidation. In this article, the environmental issues caused by VOC emissions and the trend of legislation against such emissions will be surveyed first. Several conventional control technologies will then be summarized and the characteristics of each process will be introduced. Lastly, some examples will be described to show the hybrid processes which have been industrially applied for the recovery of VOC.
