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
제7권 제2호 (1998년 4월) 17건
1.
1998.04
서비스 종료(열람 제한)
We examined whether several reeds, which are found around Ulsan area, could be used for downflow reed-bed to remove pollutants of sewage. Three kinds of reed, such as Phagmites australis, Typha orientalls, and Phalaris aundinacea L., were collected from their habitats near the Taehwa River in Ulsan City. In the minimized model system of downflow reed-bed, P. australis appeared to reduce BOD more than others did but slightly increase total amount of nitrogen(N). When P. australis were placed in the sterilized water, total nitrogen was found to be significantly increased dependent on the number of experimental plant in the sterilized state, but it was rather decreased in the non-sterilized state. With these results, microorganisms attached to P.australis roots can be thought to work for removal of pollutants. Therefore, these microorganisms and their habitat, P. australis reed bed, together can be used for sewage treatment. It was suggested that oxygen is produced by photosynthesis reaction of P. austrails. The increased oxygen may help microorganisms in their habitats to work on the removal of pollutants
2.
1998.04
서비스 종료(열람 제한)
The experiment was performed to elucidate the effect of simulated acid rain on growth of the seven crops(Daucus carota var. saliva DC., Fagopyrum esculentum Moench, Brassica campestris subsp. napus var. pekinensis Makino, Raphanus sativus var. hortensis for. acanthiformis Makino, Brassica alboglabra Bailey, Caphsicum annum L., and Perilla frutescens Britton). The pH levels of simulated acid rain ranged pH 3.1, 3.6, 4.1, 4.6, 5.1 and 5.6. The germination with each crop was influenced from simulated acid rain except buckwheat and kale. A general decrease of growth in crops was observed with increasing pH concentrations. The pattern of soluble protein was observed a tendency to decrease from acidic pH gradients. According to acidity, total DNA contents of each crop was showed a definite reduction. In conclusion, plant growth was stimulated decreasingly and the changes of total protein patterns and DNA contents extracted from leaves trended with simulated acid rain was showed seriously.
3.
1998.04
서비스 종료(열람 제한)
To investigate the effects of sulfite on the chloroplast development, etiolated barley seedlings were treated with 100 mM sulfite solution every 3 hour by spraying during 96 hours greening period. The effects were determined by chlorophyll a, b and carotenoids contents, photosynthetic electron transport activity, chlorophyll fluorescence yield and fluorescence quenching parameters.
The contents of chlorophyll a and carotenoids were decreased than that of control by treatment of sulfite over 48 hours greening. PS Ⅱ is more sensitive to sulfite than PS I is. And by the addition of DPC to the chloroplasts of the barley seedling treated with sulfite, the photoreduction of DCPIP was not recovered. In greening with sulfite treated barley leaves, Fo, Fv and Fv/Fm ratio were decreased with little difference from that of control. But qP, qNP and qR were lowed in comparison with those of controls whereas qE was slightly higher than that of control. Especially, it is interesting that qR was decreased markedly compared to that of control. The results in the change of PS I activity, Fv/Fm and qP suggest that the site of inhibition by sulfite is carbon dioxide reduction cycle.
4.
1998.04
서비스 종료(열람 제한)
Effects of aluminium(Al), soil pH and calcium(Ca) on growth response and heavy metal accumulation and regulation of nitrogen fixation in Melilotus suaveolens seedlings, a biennial legume plant dominating in the disturbed area, were quantitatively analyzed during the growing periods. Accumulation of metals in each organ of M. suaveolens was increased with the lowering of pH. Al contents in leaf and root treated with 30ppm Al at pH 4.2 on the 28th day after treatment were 8 and 11 folds higher than those of control, while the contents with 100ppm Al were 21 and 24 folds as compared to control. The significent inhibition in Al contents was induced by 100ppm Al and Ca at pH 6.5. Increased metals inhibited height at pH 4.2 and the growth inhibition due to Al was reversed by the addition of Ca, suggesting that growth correlates to the pH value. Chlorophyll contents in leaves increased during growth stage were inhibited by Al treatments. The biomass was decreased with the lowering of pH and the increase of concentrations. 100ppm Ca treatment resulted in 5.1-5.9% increase of the biomass as compared to that of 100ppm Al. Specific nitrogen fixation activities in nodules in the 100ppm Al at pH 4.2 and pH 6.5 were reduced to 35. 2% and 52.2% of control, on the 28th day after treatment, while the combination of Al and Ca induced inhibition of activities to 4.6% and 69.9% of control, respectively. Total amount of nitrogen fixation was reduced by 10% as compared to control with the treatment of 100ppm Al at pH 4.2 due to the inhibition of nodule formation. However the stimulative effect of nodule formation was enhanced by the combination of 100ppm Al and Ca and lowering of pH.
5.
1998.04
서비스 종료(열람 제한)
Environmental problems caused by certain geologic conditions include pollution of soil by heavy metal, acidization of soils, acid mine drainage, ground-water pollution, and natural radioactivity, as well as geological hazards such as landslide and subsidence. The acid mine drainage contains large amount of heavy metals and, therefore, cause serious pollution onto the nearby drainage systems and soils. In spite of this prospective environmental danger, few studies have been done on the acid mine drainage derived from non-metallic ore deposits such as pyrophyllite(Napseok) deposits. The sulfide-bearing pyrophyllite ores, alteration zones, and mine tailings of pyrophyllite deposits produce acid mine drainage by the oxidation of weathering. Compared to the fresh host rocks, the ores and altered rocks of pyrophyllite deposits produce acidic solution which contain higher amount of heavy metals because of their lower buffering capacity to acid solution.
The pHs of mine water and nearby stream water of pyrophyllite deposits are 2.1∼3.7, which are strongly acidic and much lower than that (6.2∼7.2) of upstream water and than that (6.8∼7.6) of the stream water derived from the non-mineralized area. This study reveals that this acid mine drainage can affect the downstream area which is 8km far from the pyrophyllite deposits, even though the drainage is diluted with abundant non-contaminated river water. This suggests that not only acid mine drainage but also the sulfide-bearing sediments originated from the pyrophyllite deposits move downstream and form acidic water through continuous oxidation reaction.
The heavy metals such as Pb, Zn, Cu, Cd, Ni, Mn and Fe are enriched in the mine water of low pH, and their contents decrease as the pH of mine water increases because of the influx of fresh stream water. Soils of the pyrophyllite deposits are characterized by high contents of heavy metals. The stream sediments containing the yellowish brown precipitates formed by neutralization of acid mine drainage occur in all parts of the stream derived from the pyrophyllite deposits, and the sediments also contain high amounts of heavy metals. In summary, the acid mine drainage of the pyrophyllite deposits is located in the upstream part of Hoidong water reservoir in Pusan contains large amounts of heavy metals and flows into the Hoidong water reservoir without any purification process. To protect the water of Hoidong reservoir, the acid mine drainage should be treated with a proper purification process.
6.
1998.04
서비스 종료(열람 제한)
A preliminary study on the chemical compositions of forty seven precipitations from March 1994 to May 1995 in Yeoncheon-gun, which is adjacent to the southern boundary of demilitarized zone (DMZ) in the northernmost tip of Kyunggi province has been performed. The metal cation and anion concentrations were measured by atomic absorption spectrometer and ion chromatography, respectively. pH/Ion meter and direct nesslerization method were used for the concentration measurements of H- ion and NH_4+ ions, respectively. Based on the data, the quantitative orders of the cation and anion average concentrations were Ca2+ > NH_4+ > Na+ > K+ > Mg2+ > H+ and SO_42- > Cl- > NO_3-, respectively. The ratio of average total anion concentration to average total cation concentration was 0.97. The average pH value of the precipitations was 5.60. These results, correlation coefficients between the ion concentrations, and monthly variations of pH value and precipitation amount are used for chemical analysis on the environmental pollution and pollutant sources in Yeoncheon-gun of Kyunggi province near DMZ.
7.
1998.04
서비스 종료(열람 제한)
The purpose of this study was to investigate the pollutions of water qualities in 30 water samples from Nakdong River, Western Nakdong River, and Suyoung Stream. COD, BOD, T-N and negative ions(F-, Cl- NO3-, SO42-) of water samples were analyzed and the correlationships between water qualities were examined.
The mean concentrations of COD(20.26ppm), BOD(25.36ppm), and T-N(18.05ppm) were the highest in the water sample of Suyoung Stream among the three streams and those of F-(0.25ppm), Cl-(27.70ppm), and SO2-(37.66ppm) in Western Nakdong River, that of NO_3,(10.81ppm) in Nakdong River. The water quality of Suyoung Stream was the worst among the three streams in Pusan area. The correlationships between water qualities were as follows ; BOD and COD showed very high correlationship(correlation coefficient, r=0.97), SO42- and NO3- did high one(0.75), and NO3- and COD, BOD did relatively high ones(0.56 and 0.48, respectively).
8.
1998.04
서비스 종료(열람 제한)
This study was conducted to evaluate water quality utilizing principal component analysis in the Nakdong River Estuary. From the results of analysis, water quality in the Nakdong River Estuary could be explained up to 65.3 percentage by three factors which were included in river loading(wastes from the Nakdong River and rainfalls ; 39.1%), sediment resuspension(13.7%) and metabolism(12.5%). In the eastern part of estuary in flowing the Nakdong River, river loading factor score(factor 1)was higher than that in western part. Sediment resuspension factor score(factor 2) was high in shallow water, while metabolism factor score(factor 3) was high in deeper water. For seasonal variations of factors score, factor 1 was highly related to rainfall season.
9.
1998.04
서비스 종료(열람 제한)
The spatial rainfall distributions accompanied by the heavy rainfalls in the Korean peninsula were classified to 6 typical patterns and synoptic characteristics of each pattern were analyzed. 274 cases of heavy rainfall events occurred for 10 years from 1981 through 1990 were used for this study.
In the 4 types of them, heavy rainfalls are not by the strongly developed but by the rapidly deepening low pressure systems, which have a well defined low and high level jets before arrival to the Korean peninsula. In another 2 types, heavy rainfalls are due to specially developed surface low pressure system. Most of the heavy rain areas are associated with the location of the low level jets and their direction and with the position of surface warm front.
In the 4 types, the heavy rain areas extend in zonal direction. And the latitudinal locations of these areas are associated with the polar low center or strong main trough over 500 hPa level. The more northwestern part of the Asia the low locates the higher latitude in the Korean Peninsula the rainfall concentration occurs at. It is also known that the seasonal drifting of the lows have some relations to the progression of summer monsoon but its characteristics change year by year.
10.
1998.04
서비스 종료(열람 제한)
PM10 concentrations were measured in underground stores located in 4 major cities, Chunchon, Wonju, Donghae and Sockcho, in Kangwon-Do using scattering light integrated type digital dust indicator. Personal exposure to PM10 for two women(housekeeper and graduate student) and a man(undergraduate student) were measured also.
The dimensional conversion factors for mass concentrations(K) showed some difference among underground stores which were 2.0, 2.7, 3.4, 2.6 ㎍/㎥·CPM in chunchon, Wonju, Donghae and Sockcho, respectively. Average PM_10 concentrations at underground stores were 178 ㎍/㎥ in Chunchon, 141 ㎍/㎥ in Wonju, 125 ㎍/㎥ in Donghe and 59 ㎍/㎥ in Sockcho. The portion of PM10 in total suspended particles was about 50∼60 % as weight.
The exposure of graduate student, housekeeper and undergraduate to PM10 during 12 hours were 1004.3 (㎍/㎥)·hr, 907.0 (㎍/㎥)·hr and 691.2 (㎍/㎥)·hr, respectively. Personal exposure to PM10 showed very different according to their activity pattern and they had more than 90 % of their PM10 exposure at indoor environment.
11.
1998.04
서비스 종료(열람 제한)
In this research, two stochastic models are considered to detect and estimate the effect of air temperature change due to industrialization in Ulsan area. Using the monthly mean minimum air temperature anomalies, the data are divided into pre-industrialization part and industrialization one for analysis. The ARMA(autoregressive moving-average) model and intervention model have been applied to the data for the analysis. The results show that the variability of minimum temperature anomalies are very significant in 1989, and also significant in 1971 when the industrialization have started. Therefore, it is stochastically possible to estimate the time when the affection of increase of the temperature concerning industrialization to climate change in Ulsan area has happened.
12.
1998.04
서비스 종료(열람 제한)
The low level atmospheric observation carried out to investigate magnitude, formation and dissipation of nocturnal surface inversion layer, also to survey relation to each meterological parameter in inversion layer at Pusan power plant for Oct. 13, 1996.
As coastal area, the surface inversion layer height was relatively high(186m), and after sunset unstable layer formated from surface to around 40m, and the inversion layer was left still in the upper layer. The surface inversion layer dissipated at 0920LST perfectly. The layer that strong inversion layer was formated, showed steep variation of potential temperature and wind speed and relative humidity.
13.
1998.04
서비스 종료(열람 제한)
A simple on-line measurement system consisting of a conventional peristaltic pump, a HPLC-type heater, and a flow-through spectrophotometer is introduced for the determination of chemical oxygen demand(COD). The system was configured such that the reaction mixture in the highly concentrated sulfuric acid medium flowing through the PTFE reaction tubing was heated at 150℃ and the absorbance of dichromate was continuously monitored at 445 nm. The same oxidation principle as in the standard procedure was employed except the use of CoSO_4 as a new effective catalyst. To test the system, potassium hydrogen phthalate was selected as a COD standard material. With suitably optimized reaction condition, the applicable concentration range depends on the initial concentration of potassium dichromate in the oxidizing reagent. With 2.0×10-3 M and 5.0×10-4 M dichromate, the linear dynamic range was observed up to 400 ppm and 100 ppm, respectively. The standards in the linear ranges were shown to be completely oxidized, which was confirmed with sodium oxalate or Mohr`s salt. In all cases, the typical reproducibility for between-runs was 2% or less. The proposed measurement system provides the valuable information for the further development of automated analysis system based on the present standard procedure.
14.
1998.04
서비스 종료(열람 제한)
Nanofiltration[NF45] and reverse osmosis membrane[HR98PP] separation treatment of dyestuff wastewater was carried out in order to seperate relatively pure water from synthetic dyestuff wastewater, which consists of reactive dye, acid dye, basic dye, direct dye, and disperse dye. The experiments were performed by using the plate and frame membrane module. In the nanoflltration and reverse osmosis membrane separation, When the NaCl concentration was 0.1, 5.0, and 20.0%, retention was 63.0, 46.0, 0.9%, respectively. When permeate flux was 125.0, 67.5, and 45.0 L/㎡·h, the osmotic pressure increased with increasing the NaCl concentration. Permeate flux of two membranes increased as temperature increased due to segmental movement of polymer of the membrane and the rejection rate of dyestuff was decreased gradually. It was found that the rejection rate was about 95% in the nanofiltration, while the reverse osmosis membrane showed a high rejection rate of 99% under all temperature and pressures conditions.
15.
1998.04
서비스 종료(열람 제한)
Organics matters including algae are the major contaminants of Nak-dong river and it`s concentration is more increasing now. The use of coagulants has been incresed for the effective treatment of drinking water, and aluminum coagulants have been the most widely used in raw water treatment. However, when inorganic metal coagulant is excessively used for long period, it would result in secondary problems, such as increasing sludge production, enhancing the cost of water treatment process, and increasing concentration of residual metal, especially aluminum. Therefore, recently, in order to reduce the use of metal coagulant and enhance the coagulation effectiveness, several alternative coagulants, such as polymeric inorganic coagulants and organic polymers, have been used in water treatment plants. The objectives of this research were (1) to determine optimum dosage concentration and compare the coagulation efficiency at various pH ranges with alum alone, alum+cationic polymer, and alum+anionic polymer, (2) to evaluate the amount of alum reduced by using organic polymer, (3) to maximize removal efficiency of organic matter and minimize the concentration of residual aluminum.
16.
1998.04
서비스 종료(열람 제한)
The spatial characteristics of stratification in Deukryang Bay were studied using observed data and analytical models. From the description of the density structure and its the potential energy anomaly (PEA) from observed data along longitudinal direction (from the mouth to head of the bay), we found that the stratification intensity could be changed strongly by density current effect during the spring-neap tidal cycle, and depth variation. To find out density current effect for the formation of the stratification in detail, we implemented a diagnostic approach by using the modified analytical model including density current, tidal current, surface heating and wind stirring. The model allowed for the observed similarities for the whole domain in the bay and increased tidal mixing efficiency value ε up to 0.006 - 0.007 as compared to the results without density current effect. We found that the density current effect was also an important key factor in determining the formation of the spatial distribution of stratification.
17.
1998.04
서비스 종료(열람 제한)
This study is concerned with properties of a thermal convection in a stably stratified Boussinesq fluid caused by partial heating at the lower boundary. For this purpose, two-dimensional, nonrotating system was employed. If the heating is very strong, convection takes the form of a turbulent plume. Otherwise, remains laminar. If the partial heating at the bottom boundary is symmetric, the convection takes the form of axisymmetric with respect to the z-axis. but heating form is not so significant as to alter the main features of the horizontal convection. The convective motion consists of two-cell with the convergence in the lower layer at the center of the partial heating area. The temperature perturbation is characterized by the temperature `Cross-Over` over the partial heating area. These features are cleared according to the increase of temperature difference between the center and side part of the bottom boundary.
