간행물

한국환경과학회지 KCI 등재 Journal of Environmental Science International

권호리스트/논문검색
이 간행물 논문 검색

권호

제27권 제7호 (2018년 7월) 13

ORIGINAL ARTICLE

1.
2018.07 서비스 종료(열람 제한)
In this study, heavy metal levels at the sediment monitoring network site upstream of the Gangjeong-Goryeong weir in the Nakdong River were surveyed from 2012 to 2016. We assessed the sediment pollution level using various pollution indexes based on ICP-MS analysis. The stream sediment pollution assessment standard, established through Regulation No. 687 of the National Institute of Environmental Research (2015), pollution load index (PLI), potential ecological risk index (RI), and mean PEL Quotient (mPELQ) were used to evaluate the sediment pollution level. We verified the representativeness of the monitoring point through the distribution of sedimentation and scour behavior by river bed surveying using anacousticDopplercurrentprofiler.
2.
2018.07 서비스 종료(열람 제한)
In this study, the ion index characteristics of small and medium urban land use types were investigated in the city of Chungju. The average temperature for each land use type was in the order: general commercial district (29.59℃) > general residential district (28.34℃) > productive green district (28.31℃). The average relative humidity was in the order: productive green district (70.12%) > general residential district (69.93%) > general commercial district (66.48%). The average wind speed was in the order: productive green district (0.95 m/s) > general commercial district (0.87 m/s) > general residential district (0.54 m/s). Positive and negative ions were investigated to determine the ion index by land use type. The average amount of positive ion generated was in the order: general commercial district (737 ea/cm3) > general residential district (492 ea/㎤) > productive green district (445 ea/㎤). The average negative ion production decreased in the order: productive green district (930 ea/㎤) > general residential district (754 ea/㎤) > general commercial district (744 ea/㎤). The ion index calculated from measured data can be arranged in the order: productive green district (2.09) > general residential district (1.53) > general commercial district (1.01). These results confirm the state of positive and negative ion generation in each land use type. Further, the differences in the ion index by land use type were confirmed. However, a limitation of this study is that simple summer measurements were conducted, and seasonal characteristics were not considered. Therefore, any future investigation and research should consider seasonal variation characteristics.
3.
2018.07 서비스 종료(열람 제한)
Agricultural meteorological information is an important resource that affects farmersʼ income, food security, and agricultural conditions. Thus, such data are used in various fields that are responsible for planning, enforcing, and evaluating agricultural policies. The meteorological information obtained from automatic weather observation systems operated by rural development agencies contains missing values owing to temporary mechanical or communication deficiencies. It is known that missing values lead to reduction in the reliability and validity of the model. In this study, the hierarchical Bayesian spatio–temporal model suggests replacements for missing values because the meteorological information includes spatio–temporal correlation. The prior distribution is very important in the Bayesian approach. However, we found a problem where the spatial decay parameter was not converged through the trace plot. A suitable spatial decay parameter, estimated on the bias of root–mean–square error (RMSE), which was determined to be the difference between the predicted and observed values. The latitude, longitude, and altitude were considered as covariates. The estimated spatial decay parameters were 0.041 and 0.039, for the spatio-temporal model with latitude and longitude and for latitude, longitude, and altitude, respectively. The posterior distributions were stable after the spatial decay parameter was fixed. root mean square error (RMSE), mean absolute error (MAE), mean absolute percentage error (MAPE), and bias were calculated for model validation. Finally, the missing values were generated using the independent Gaussian process model.
4.
2018.07 서비스 종료(열람 제한)
Weather is the most influential factor for crop cultivation. Weather information for cultivated areas is necessary for growth and production forecasting of agricultural crops. However, there are limitations in the meteorological observations in cultivated areas because weather equipment is not installed. This study tested methods of predicting the daily mean temperature in onion fields using geostatistical models. Three models were considered: inverse distance weight method, generalized additive model, and Bayesian spatial linear model. Data were collected from the AWS (automatic weather system), ASOS (automated synoptic observing system), and an agricultural weather station between 2013 and 2016. To evaluate the prediction performance, data from AWS and ASOS were used as the modeling data, and data from the agricultural weather station were used as the validation data. It was found that the Bayesian spatial linear regression performed better than other models. Consequently, high-resolution maps of the daily mean temperature of Jeonnam were generated using all observed weather information.
5.
2018.07 서비스 종료(열람 제한)
With rapid economic growth, the urban environment has created a problem of human physical and mental illness. In order to solve these problems, urban forests have emerged as a way to mitigate the environmental risks through improving the polluted environment of the city and improve the quality of life. As the urban forests have expanded, the school forests movement has also been taking an important place recently. The study focused on the performance of school forests by comparing the perceptions among teachers and students about their functions. The questionnaire was composed of 4 questions concerning human matters, 10 questions for space recognition, 4 questions for thermal environment, 2 questions for health promotion, and 20 total questions for composition of survey items. The reliability of the school forest function, number of tree planting areas and quantities, the harmony of the planting, and the satisfaction of the school forest were analyzed in the questionnaire conducted by the school members. Although it does not recognize school forests, it has a positive response to the green space that is built outdoors. It is considered that outdoor education and environmental education are sufficient in school forests and green spaces. The results showed that the outdoor green space was more satisfactory when compared with the general school. Teachers and students' preferences were similar to 'seasonal changes' and' trees of various colors and shapes'. The reliability analysis between each item shows that the coefficient for cronbach ' s α was . 700 to . 834. The purpose of this study is to identify the perception of forest function among school forest members and to utilize them as a basic data in the future.
6.
2018.07 서비스 종료(열람 제한)
Road freezing caused by snowfall during wintertime causes traffic congestion and many accidents. To prevent such problems, we developed, in this study, a system to predict road freezing based on weather forecast data and the freezing generation modules. The weather forecast data were obtained from a high-resolution model with 1 km resolution for Jeju Island from 00:00 KST on December 1, 2017, to 23:00 KST on February 28, 2018. The results of the weather forecast data show that index of agreement (IOA) temperature was higher than 0.85 at all points, and that for wind speed was higher than 0.7 except in Seogwipo city. In order to evaluate the results of the freezing predictions, we used model evaluation metrics obtained from a confusion matrix. These metrics revealed that, the Imacho module showed good performance in precision and accuracy and that the Karlsson module showed good performance in specificity and FP rate. In particular, Cohen’s kappa value was shown to be excellent for both modules, demonstrating that the algorithm is reliable. The superiority of both the modules shows that the new system can prevent traffic problems related to road freezing in the Jeju area during wintertime.
7.
2018.07 서비스 종료(열람 제한)
From November 2013 to December 2016, ambient fine particulate matter (PM2.5) was sampled in the downtown area of Jeju City, South Korea, which has seen rapid urbanization. The atmospheric concentrations of elements were measured in the PM2.5 samples. This study focused on Cd, Cr, Cu, Mn, Ni, Pb, As, Sb, Sn, V, and Zn. The concentrations of Al, Na, K, Fe, Ca, Mg, Sr, and La were also obtained for reference. The objectives of this study were to examine the contributions of these elements to PM2.5 concentrations in downtown Jeju City, and to investigate the inter-element relationships and the elemental sources by using enrichment factors and principal components analysis (PCA). A composition analysis showed that the 19 elements constituted 6.65 % of the PM2.5 mass, and Na, K, Al, Fe, Ca, Mg, and Zn constituted 98 % of the total ion mass. Seasonal trend analysis for the sampling period indicated that the concentrations of the elements increased from November to April. However, no substantial seasonal variations were found in the concentrations of the elements. The composition ratios of some elements (Cu/Zn, Cu/Cd, Cu/Pb, V/Ni, and V/La) were found to be out of range when compared to the literature from other urban areas. The ratios between the elements and the PCA results showed that local contaminant sources in Jeju City rarely influence the composition of PM2.5. This suggests that the major sources of PM2.5 in Jeju City may include long-range transport of fine particulate matter produced in other areas.
8.
2018.07 서비스 종료(열람 제한)
This study conducted to analyze the growth characteristics of old Prunus yedoensis on Jeju island. The diameter growth per year was measured using a DTRS-2000 instrument. The DBH, ground DBH and height of the investigated P. yedoensis were 137 cm, 143 cm, and 15.5 m, respectively. Our analysis showed that the age of the old P. yedoensis was 93 years. An annual diameter growth of 2.85 mm±0.96 was observed. The result of age estimation, about 265±64 years in P. yedoensis on Jeju island. This information could be useful to understand the annual diameter growth characteristics the P. yedoensis distributed on Jeju island.
9.
2018.07 서비스 종료(열람 제한)
Agricultural soils around springwaters heavily affected by pesticide run-off and around wells considering the regional characteristics were collected at 24 stations in Jeju Island, and the physicochemical properties and adsorption and leaching characteristics of four nonionic pesticides (diazinon, fenitrothion, alachlor, and metalaxyl) were investigated. The values of the major soil factors affecting the adsorption and leaching of pesticides, namely, soil pH(H2O), organic matter content, and cation exchange capacity (CEC), were in the range of 4.64 ∼ 8.30, 0.9 ∼ 13.1% and 12.7 ∼ 31.7 meq/100 g, respectively. The Freundlich constant, KF value, which gives a measure of the adsorption capacity, decreased in the order of fenitrothion > diazinon > alachlor > metalaxyl, which was identical to their lower water solubility. Among the collected soils, the KF value was very highly correlated with organic matter content (r2 = 0.800 ∼ 0.876) and CEC (r2 = 0.715 ∼ 0.825) and showed a high correlation with clay content (r2 = 0.473 ∼ 0.575) and soil pH(H2O) (r2 = 0.401 ∼ 0.452). The leaching of pesticides in the soil column showed a reverse relationhip with their adsorption in soils, i.e., the pesticides leached more quickly for the soils with lower values of organic matter content and CEC among the soils and for the pesticides with higher water solubility.
10.
2018.07 서비스 종료(열람 제한)
This research investigated the characteristics of PM10 and PM2.5 concentration at roadside (Choryangdong) and residential (Sujeongdong) locations in Busan. The PM10 concentration at roadside and residential locations were 50.5 and 42.9 ㎍/m3, respectively, and PM2.5 at roadside and residential were 28.1 and 23.9 ㎍/m3, respectively. The roadside/residential ratio of PM10 and PM2.5 concentration were 1.18, and the PM2.5/PM10 ratio at roadside and residential were 0.55 and 0.56, respectively. The PM10 concentration in spring at roadside were 64.6 ㎍/m3, and were the highest, followed by 48.0 ㎍/m3 and 45.2 ㎍/m3 in winter and summer. Number of exceedances per year of the daily limit value for PM10 at roadside and residential were 66 and 39 days, respectively. The PM10 and PM2.5 concentration, and PM2.5/PM10 ratio at roadside were 53.0 ㎍/m3, 29.0 ㎍/m3 and 0.55 for day, and 45.5 ㎍/m3, 26.7 ㎍/m3 and 0.59 for night, respectively. These results indicate that understanding the relationship between roadside and residential could provide insight into establishing a strategy to control urban air quality.
11.
2018.07 서비스 종료(열람 제한)
This research investigated the characteristics of NO and NO2 concentration at roadside (Choryangdong) and residential (Sujeongdong) locations in Busan. The NO concentration at roadside and residential were 34.7 and 8.0 ppb, respectively, and NO2 at roadside and residential were 31.6 and 18.0 ppb ㎍/㎥ , respectively. The NO concentration was the highest in winter at roadside at 37.1 ppb, followed by 35.0 ppb and 34.0 ppb in summer and fall, respectively. NO2 concentration was the highest in spring at roadside at 39.6 ppb, followed by 30.4 ppb and 28.3 ppb in fall and winter, respectively. Number of exceedances per year of 1 hr limit value (0.10 ppm) for NO2 at roadside and residential were 3,585 and 3 hours, respectively. Number of exceedances per year of 24 hr limit value (0.06 ppm) for NO2 at roadside and residential were 32 and 1 days, respectively. Number of exceedances per year of 1 hr limit value (0.1 ppm) for O3 at roadside and residential were 1 and 14 days, respectively. These results indicated that understanding the relationship between roadside and residential could provide insight into establishing a strategy to control urban air quality.
12.
2018.07 서비스 종료(열람 제한)
This study observed particulate matter (PM2.5 and PM10) in the downtown area of Jeju City, South Korea, to understand the chemical composition of particulates based on an analysis of the water-soluble ionic species contained in the particles. The mass fraction of the ionic species in the sampled PM10 and PM2.5 was 44.3% and 42.2%, respectively. In contrast, in Daegu City and Suwon City, the mass fraction of the ionic species in PM2.5 was higher than that in PM10. The chloride depletion percentage of PM10 and PM2.5 in Jeju City was higher than 61% and 66%, respectively. The contribution of sea-salt to the mass of PM10 (5.9%) and PM2.5 (2.6%) in Jeju City was similar to that in several coastal regions of South Korea. The mass ratio of Cl- to Na+ in the downtown area of Jeju City was comparable to that in some coastal regions, such as the Gosan Area of Jeju Island, Deokjeok Island, and Taean City. The mass fraction of sea-salt in PM10 and PM2.5 was very low, and the concentration of sodium and chloride ions in PM10 was not correlated with those in PM2.5 (R2 < 0.2), suggesting that the effects of sea-salt on the formation of particulate matter in Jeju City might be insignificant. The relationship between NH4 + and several anions such as SO4 2-, NO3 -, and Cl-, as well as the relationship between the measurement and calculation of ammonium ion concentration, suggested that sea-salts may not react with H2SO4, and (NH4)2SO4 may be a major secondary inorganic aerosol component of PM2.5 and PM10 in Jeju City.
13.
2018.07 서비스 종료(열람 제한)
In this study, a metal-organic framework (MOF) material NH2-MIL-101(Fe) was synthesized using the solvothermal method, and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV-visible spectrophotometry, field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and surface area measurements. The XRD pattern of the synthesized NH2-MIL-101(Fe) was similar to the previously reported patterns of MIL-101 type materials, which indicated the successful synthesis of NH2-MIL-101(Fe). The FT-IR spectrum showed the molecular structure and functional groups of the synthesized NH2-MIL-101(Fe). The UV-visible absorbance spectrum indicated that the synthesized material could be activated as a photocatalyst under visible light irradiation. FE-SEM and TEM images showed the formation of hexagonal microspindle structures in the synthesized NH2-MIL-101(Fe). Furthermore, the EDS spectrum indicated that the synthesized material consisted of Fe, N, O, and C elements. The synthesized NH2-MIL-101(Fe) was then employed as an adsorbent and photocatalyst for the removal of Indigo carmine and Rhodamine B from aqueous solutions. The initial 30 min of adsorption for Indigo carmine and Rhodamine B without light irradiation achieved removal efficiencies of 83.6% and 70.7%, respectively. The removal efficiencies thereafter gradually increased with visible light irradiation for 180 min, and the overall removal efficiencies for Indigo carmine and Rhodamine B were 94.2% and 83.5%, respectively. These results indicate that the synthesized MOF material can be effectively applied as an adsorbent and photocatalyst for the removal of dyes.