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
제26권 제6호 (2017년 6월) 10건
ORIGINAL ARTICLE
1.
2017.06
서비스 종료(열람 제한)
This study was performed to investigate the geochemical and benthic environment of three shellfish farms in Suncheon Bay during the period of September 2014 ~ April 2015. Three sampling stations were selected; St.1 is the shellfish farm of razor clam near Jangsan area. St.2 is the shellfish farm of small ark shell near Hwapo area and St.3 is the shellfish farm of razor clam near Yongdu area. Razor clam was the dominant species at St.1, small ark shell and granulated ark shell were dominant at St.2 and St.3, respectively. Granulated ark shell inhabited St.3, although it is not cultured at that station. This station’s exposure to air during the ebb tide and sediment composition likely provides the appropriate habitat for granulated ark shell species. Analysis of the number of different species showed that 8 benthos species were found to be distributed at St.1, 18 species at St.2, and 13 species at St.3. Among three stations, the highest Ignition Loss (IL), Chemical Oxygen Demand (COD) and Acid Volatile Sulfide (AVS) values were obtained from the sediment at St.2. The analysis of pore water from St.2 also showed the highest values of Total Organic Carbon (TOC), ammonia (NH4 +), Dissolved Inorganic Nitrogen (DIN) and phosphate (PO4 3-). These results are related to the fact that species dominance and richness is the highest in St.2.
2.
2017.06
서비스 종료(열람 제한)
Dielectric Barrier Discharge (DBD) plasma is a new technique for use in environmental pollutant degradation, which is characterized by the production of hydroxyl radicals as the primary degradation species. Due to the short lifetime of the chemically active species generated during the plasma reaction, the dissolution of the plasma gas has a significant effect on the reaction performance. The plasma reaction performance can be enhanced by combining the basic plasma reactor with a homogenizer system in which the bubbles are destroyed and turned into micro-bubbles. For this purpose, the improvement of the dissolution of plasma gas was evaluated by measuring the RNO (N-dimethyl-4-nitrosoaniline, an indicator of the generation of OH radicals). Experiments were conducted to evaluate the effects of the diameter, rotation speed, and height of the homogenizer, pore size, and number of the diffuser and the applied voltage on the plasma reaction. The results showed that the RNO removal efficiency of the plasma reactor combined with a homogenizer is two times higher than that of the conventional one. The optimum rotor size and rotation speed of the homogenizer were 15.1 mm, and 19,700 rpm, respectively. Except for the lowest pore size distribution of 10-16 μm, the pore size of the diffuser showed little effect on RNO removal.
3.
2017.06
서비스 종료(열람 제한)
In order to investigate the adsorption characteristics for Sr ion using the Na-X zeolite synthesized from coal fly ash, batch tests and response surface analyses were carried out. The adsorption kinetic data for Sr ions, using Na-X zeolite, fitted well with the pseudo-second-order model. The uptake of Sr ions followed the Langmuir isotherm model, with a maximum adsorption capacity of 196.46 mg/g. Thermodynamic studies were conducted at different reaction temperatures, with the results indicating that Sr ion adsorption by Na-X zeolite was an endothermic (ΔHo>0) and spontaneous (ΔGo<0) process. Using the response surface methodology of the Box-Behnken method, initial Sr ion concentration (X1), initial temperature (X2), and initial pH (X3) were selected as the independent variables, while the adsorption of Sr ions by Na-X zeolite was selected as the dependent variable. The experimental data fitted well with a second-order polynomial equation by multiple regression analysis. The value of the determination coefficient (R2=0.9937) and the adjusted determination coefficient (adjusted R2=0.9823) was close to 1, indicating high significance of the model. Statistical results showed the order of Sr removal based on experimental factors to be initial pH > initial concentration > temperature.
4.
2017.06
서비스 종료(열람 제한)
The Weather Research and Forecasting (WRF) model and Vegetation Photosynthesis and Respiration Model (VPRM) were coupled to simulate atmospheric CO2 concentrations. The performance of the WRF-VPRM to simulate regional scale CO2 concentration was estimated over coastal basin areas. Either Hestia 2011(HST) or Vulcan 2002(VUL) anthropogenic CO2 emission data were used in two numerical experiments for the study regions. Simulated meteorological variables were validated with ground and background CO2 measurement data, and the results show that the model captured temporal variations of CO2 concentration on a daily basis. CO2 directional analysis revealed that the dominant CO2 emission sources are located S and SW. The simulated Net Ecosystem Exchange (NEE) agreed relatively well with measured CO2 fluxes at each vegetation class site, showing approximately 40% at max improvement at shrub areas.
5.
2017.06
서비스 종료(열람 제한)
A model coupling a meteorological predictive model and a vegetation photosynthesis and respiration model was used to simulate CO2 concentrations over coastal basin areas, and modeling results were estimated with aircraft observations during a massive sampling campaign. Along with the flight tracks, the model captured the meteorological variables of potential temperature and wind speed with mean bias results of 0.8℃, and 0.2 m/s, respectively. These results were statistically robust, which allowed for further estimation of the model’s performance for CO2 simulations. Two high-resolution emission data sets were adopted to determine CO2 concentrations, and the results show that the model underestimated by 1.8 ppm and 0.9 ppm at higher altitude over the study areas during daytime and nighttime, respectively, on average. Overall, it was concluded that the model’s CO2 performance was fairly good at higher altitude over the study areas during the study period.
6.
2017.06
서비스 종료(열람 제한)
This research investigates the characteristics of meteorological variation and fine particles (PM10 and PM2.5) for case related to the haze occurrence (Asian dust, long range transport, stationary) in Busan. Haze occurrence day was 559 days for 20 years (from 1996 to 2015), haze occurrence frequency was 82 days (14.7%) in March, followed by 67 days (12.0%) in February and 56 days (10.0%) in May. Asian dust occurred most frequently in spring and least in winter, whereas haze occurrence frequency was 31.5% in spring, 29.7% in winter, 21.1% in fall, and 17.7% in summer. PM10 concentration was highest in the occurrence of Asian dust, followed by haze and haze + mist, whereas PM2.5 concentration was highest in the occurrence of haze. These results indicate that understanding the relation between meteorological phenomena and fine particle concentration can provide insight into establishing a strategy to control urban air quality.
7.
2017.06
서비스 종료(열람 제한)
This research investigates the characteristics of metallic and ionic elements in PM10 and PM2.5 on haze day and non-haze day in Busan. PM10 concentration on haze day and non-haze day were 85.75 and 33.52 ㎍/m³ , respectively, and PM2.5 on haze day and non-haze day were 68.24 and 23.86 ㎍/m³ , respectively. Contribution rate of total inorganic water-soluble ion to PM10 mass on haze day and non haze day were 58.2% and 61.5%, respectively, and contribution rate of total water-soluble ion to PM2.5 mass on haze day and non haze day were 58.7% and 64.7%, respectively. Also, contribution rate of secondary ion to PM10 mass on haze day and non haze day were 52.1% and 47.5%, respectively, and contribution rate of secondary ion to PM2.5 mass on haze day and non haze day were 54.4% and 53.6%, respectively. AC (anion equivalents)/CE (cation equivalents) ratio of PM10 mass on haze day and non haze day were 1.09 and 1.0, respectively, and AC/CE ratios of PM2.5 mass on haze day and non haze day were 1.12 and 1.04, respectively. Also, SOR (Sulfur Oxidation Ratio) of PM10 mass on haze day and non haze day were 0.32 and 0.17, respectively, and SOR of PM2.5 on haze day and non haze day were 0.30 and 0.15, respectively. Lastly, NOR (Nitrogen Oxidation Ratio) of PM10 on haze day and non haze day were 0.17 and 0.08, respectively, and NOR of PM2.5 on haze day and non haze day were 0.13 and 0.06, respectively.
8.
2017.06
서비스 종료(열람 제한)
In this study, we analyzed the changes in the echolocation and prey-capture behavior of the horseshoe bat Rhinolophus ferrumequinum from search phase to capture time. The experiment was conducted in an indoor free-flight room fitted with an ultra-high-speed camera. We found that the bats searched for food while hanging from a structure, and capturing was carried out using the flight membrane. In addition, it was confirmed that the mouth and uropatagium were continuously used in tandem during the capturing process. Furthermore, using Constant Frequency (CF), we confirmed that the prey catching method reflected the wing morphology and echolocation pattern of R. ferrumequinum. The echolocation analysis revealed that the pulse duration, pulse interval, peak frequency, start-FM-bandwidth, and CF duration decreased as the search phase approached the terminal phase. Detailed analysis of echolocation pulse showed that the end-FM bandwidth, which increases as it gets nearer to the capture time of prey, was closely related to the accurate grasp of the location of an insect. At the final moment of prey capture, the passive listening that stopped the divergence of the echolocation was identified; this was determined to be the process of minimizing the interruption from the echo of the echolocation call emitted from the bat itself and sound waves emitted from the prey.
9.
2017.06
서비스 종료(열람 제한)
Termites (Isoptera) are classified into approximately 3,106 species. In Korea, only one species has been identified, which is Reticulitermes speratus kyushuensis Morimoto. The termite, a social insect, is known to play an important role in nutrient cycling of the ecosystem, although some species of termites are well-known pests attacking wooden structures or any plant materials. However, there is a lack of research about termites in Korea, including aspects such the taxonomy, physiology, and ecology of termites. This study was carried out to provide valuable basic data on the ecological role of termites in an ecosystem in Korea for the future studies. For the experiments, soil and termite samples were randomly collected from Mt. Hwajang located in Jikdong-ri, Eonyang-eup, Ulju-gun, Korea between October 5 and 30, 2015. Analysis results showed that there were no significant differences in soil chemical properties between the soil samples just after air-drying and one year elapsed without any treatment. The treated soil with termites showed significantly higher than the soil without termite treatment. Chemical properties of total nitrogen, organic matter, available phosphate, pH, Calcium(Ca), Potassium(K) and Magnesium(Mg) in soil treated with termites were 1.11 ± 0.3 g kg-1, 43.3 ± 12.4 g kg-1, 27.4 ± 2.9 mg kg-1, 4.56 ± 0.2, 0.82 ± 0.2 cmolc kg-1, 3.18 ± 1.4 cmolc kg-1, 1.73 ± 1.1 cmolc kg-1, respectively. The values of soil property of without termite treatment were 0.56 ± 0.1 g kg-1, 30.5 ± 3.1 g kg-1, 24.0 ± 4.7 mg kg-1, 4.09 ± 0.1, 0.71 ± 0.2 cmolc kg-1, 2.88 ± 1.5 cmolc kg-1, 1.30 ± 0.7 cmolc kg-1, respectively. These results suggest that inhabitation of termites could improve soil chemical properties in an ecosystem.
TECHNICAL NOTE
10.
2017.06
서비스 종료(열람 제한)
This study aimed to remove organic matter and heavy metals that could affect the recycling of soils contaminated by heavy metals, by means of electrolysis, carried out simultaneously with the leaching of the soil. To ensure better experimental equipment, a soil electrolysis apparatus, equipped with spiral paddles, was used to agitate the heavy-metal-contaminated soil effectively. The heavy-metal-contaminated soil was electrolyzed by varying the voltage to 5 V(Condition 1), 15 V(Condition 2), and 20 V(Condition 3), under the optimal operating conditions of the electrolysis apparatus, as determined through previous studies. The results showed that the pH of the electrolyte solution and the heavy-metal-contaminated soil, after electrolysis, tended to decrease with an increase in voltage. The highest removal efficiencies of TOC and CODCr were 18.8% and 29.1%, 38.8% and 4.2%, and 33.3% and 50.0%, under conditions 1, 2 and 3, respectively. Heavy metals such as Cd and As were not detected in this experiment. The removal efficiencies of Cu, Pb and Cr were 4.7%, 8.3% and 2.1%, respectively, under Condition 1, while they were 42.9%, 15.2% and 22.1%, respectively, under Condition 2, and 4.7%, 23.0%, and 24.9%, respectively, under Condition 3. These results suggest that varying the voltage with the soil electrolysis apparatus for removing contaminants for the recycling of heavy-metal-contaminated soil allows the selective removal of contaminants. Therefore, the results of this study can be valuable as basic data for future studies on soil remediation.
