• Journal of the Korean earth science society
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• v.40 no.5
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• pp.476-486
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• 2019

This study examines the controlling role of synoptic disturbances on $PM_{10}$ spring variability in the Korean Peninsula by using empirical orthogonal function (EOF) and back trajectory analyses. Three leading EOF modes are identified, and a lead-lag analysis suggests that $PM_{10}$ variabilities be closely related to the synoptic weather systems. The first EOF shows the spatially homogeneous distribution of $PM_{10}$, which is influenced by travelling anticyclonic disturbance with negative precipitation and descending motion. The second and third modes exhibit the dipole structures of $PM_{10}$, being associated with propagating cyclones. Furthermore, the back-trajectory analysis suggests that the transport of pollutants by anomalous winds associated with synoptic disturbances also contribute to the altered $PM_{10}$ concentration. Hence, a substantial synoptic control should be considered in order to fully understand the $PM_{10}$ spatiotemporal variability.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.4
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• pp.330-336
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• 2018

El $Ni{\tilde{n}}o$ would cause extreme weather conditions, which would result in a negative impact on crop production. The objective of this study was to assess the impact of El $Ni{\tilde{n}}o$ on spring kimchi cabbabe production for the period from 1981- 2016 in South Korea. In this study, years with less than 1.0 Oceanic $Ni{\tilde{n}}o$ index were classified into non El $Ni{\tilde{n}}o$ years. The other years were classified as El $Ni{\tilde{n}}o$ years. The national average production of spring kimchi cabbage in El $Ni{\tilde{n}}o$ years ($3,800kg\;10a^{-1}$) tended to be less than that in non El $Ni{\tilde{n}}o$ years ($4,016kg\;10a^{-1}$). However, there was no significant differences (p = 0.078) in the production between these groups of years. The averaged production of spring kimchi cabbage of El $Ni{\tilde{n}}o$ end years ($3,707{\pm}331kg\;10a^{-1}$) was less than those of El $Ni{\tilde{n}}o$ start years and non El $Ni{\tilde{n}}o$ years by 186 and $309kg\;10a^{-1}$, respectively. Still, such difference was not significant statistically (p=0.127), either. In contrast, there were provinces where the production of spring kimchi cabbage had significant differences by El $Ni{\tilde{n}}o$ occurrence. For example, El $Ni{\tilde{n}}o$ end years had significantly less spring kimchi cabbage production than El $Ni{\tilde{n}}o$ start years and non El $Ni{\tilde{n}}o$ years in Gangwon (p=0.038) and Gyeongbuk (p=0.053) provinces. It appeared that differences in cabbage production resulted from short sunshine duration, which merits further analysis on the impact of extreme weather condtions during El $Ni{\tilde{n}}o$ years on crop production.

• Journal of Environmental Science International
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• v.15 no.12
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• pp.1125-1139
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• 2006

The cluster analysis of diurnal precipitation patterns is performed by using daily precipitation of 59 stations in South Korea from 1973 to 1996 in four seasons of each year. Four seasons are shifted forward by 15 days compared to the general ones. Number of clusters are 15 in winter, 16 in spring and autumn, and 26 in summer, respectively. One of the classes is the totally dry day in each season, indicating that precipitation is never observed at any station. This is treated separately in this study. Distribution of the days among the clusters is rather uneven with rather low area-mean precipitation occurring most frequently. These 4 (seasons)$\times$2 (wet and dry days) classes represent more than the half (59 %) of all days of the year. On the other hand, even the smallest seasonal clusters show at least $5\sim9$ members in the 24 years (1973-1996) period of classification. The cluster analysis is directly performed for the major $5\sim8$ non-correlated coefficients of the diurnal precipitation patterns obtained by factor analysis In order to consider the spatial correlation. More specifically, hierarchical clustering based on Euclidean distance and Ward's method of agglomeration is applied. The relative variance explained by the clustering is as high as average (63%) with better capability in spring (66%) and winter (69 %), but lower than average in autumn (60%) and summer (59%). Through applying weighted relative variances, i.e. dividing the squared deviations by the cluster averages, we obtain even better values, i.e 78 % in average, compared to the same index without clustering. This means that the highest variance remains in the clusters with more precipitation. Besides all statistics necessary for the validation of the final classification, 4 cluster centers are mapped for each season to illustrate the range of typical extremities, paired according to their area mean precipitation or negative pattern correlation. Possible alternatives of the performed classification and reasons for their rejection are also discussed with inclusion of a wide spectrum of recommended applications.

• Journal of environmental and Sanitary engineering
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• v.18 no.3 s.49
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• pp.78-88
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• 2003

This study was conducted to investigate the relation between ozone concentration and the affecting factors in Seosan City of Korea from Jan. 2002 to Dec. 2002. We analyzed the air pollutants such as NO$_2$, PM$_{10} $,SO$_2$, CO and the meteorological factors including solar radiation, air temperature, wind speed and relative humidity. The analytical data were taken statistics by SPSS method. The results were as follows: The seasonal average concentration of ozone were detected 35.0 ppb in Spring, 25.4 ppb in Summer, 23.5 ppb in Autumn and 21.4 ppb in Winter. So the difference of concentrations showed significantly in statistics. The hourly ozone concentration in a day was increased at 7-9 AM, peaked at 3-4 PM. The correlation coefficients was negative to ozone concentration and NO$_2$, SO$_2$, CO, relative humidity, but positive to solar radiation, air temperature, wind speed. With stepwise multiple regression analysis on the 8 factors such as NO$ _2$, PMSO$_{10}$,SO$_2$, CO, solar radiation, air temperature, wind speed and relative humidity, the seasonal primary factors were air temperature in spring, relative humidity in summer and solar radiation in autumn and winter. The above results suggest that ozone is the secondary pollutant by photochemical reaction as the concentration of ozone was increased with the raise of solar radiation.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.3
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• pp.442-450
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• 2015

Climate temperature affects animal production. This study was conducted to evaluate whether climatic conditions affect beef carcass characteristics of Korean cattle steers. The monthly carcass characteristics of Korean cattle steers (n = 2,182,415) for 8 yr (2006 through 2013) were collected from the Korean Institute for Animal Products Quality Evaluation. Daily climate temperature (CT) and relative humidity (RH) data were collected from the Korean Meteorological Administration. Weather conditions in South Korea during summer were hot and humid, with a maximum temperature of $28.4^{\circ}C$ and a maximum RH of 91.4%. The temperature-humidity index (THI), calculated based on CT and RH, ranges from 73 to 80 during summer. Winter in South Korea was cold, with a minimum temperature of $-4.0^{\circ}C$ and a wind-chill temperature of $-6.2^{\circ}C$. Both marbling score (MS) and quality grade (QG) of Korean cattle steer carcasses were generally best (p<0.05) in autumn and worst in spring. A correlation analysis showed that MS and QG frequencies were not associated (p>0.05) with CT. Yield grade (YG) of Korean cattle steer carcasses was lowest (p<0.05) in winter (November to January) and highest in spring and summer (May to September). A correlation analysis revealed that YG frequency was strongly correlated ($r{\geq}0.71$; p<0.01) with CT and THI values. The rib eye area, a positive YG parameter, was not associated with CT. Backfat thickness (BT), a negative YG factor, was highest in winter (November and December). The BT was strongly negatively correlated ($r{\leq}-0.74$; p<0.01) with CTs. Therefore, the poor YG during winter is likely due in part to the high BT. In conclusion, YG in Korean cattle steer carcasses was worst in winter. QGs were not associated with winter or summer climatic conditions.

• The Journal of the Korean Society for Microbiology
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• v.18 no.1
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• pp.1-9
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• 1983

The author studied on the distribution of V. parahaemolyticus among sea water, sea mud, and various marine products in Jeju, Keoje, Namhae, Yockji, Busan, and Masan on the southern seas of Korea from winter in 1981 to summer in 1982. The author studies for the isolated strains to bacteriological identification Kanagawa phenomenon(hemolytic activity) on Modified Wagatuma blood agar plates and serotypes with anti V. parahaemolyticus. The results obtained were as follows:. 1. V. parahaemolyticus was isolated in 713 strains(28.3%) among 2519 total specimens of sea water, sea mud, and various marine products. 2. The isolation rates of V. parahaemolyticus in summer season were higher than in spring and winter season. Above results were 304 strains(32.6%) among 932 specimens in summer, 160 strains (28.1%) among 570 specimens in spring, 149 strains(14.6%) among 1017 specimens in winter, respectively. 3. The hemolysis on Modified Wagatuma agar added human erythrocytes was 66.0% of positive Kanagawa phenomenon, and was 34.0% of negative Kanagawa phenomenon, respectively. 4. The distributions of serotypes of V. parahaemolyticus isolated were from KI to K VIII of K pooling antisera. The results were 6 strains(6.6%) on K 1 of K I, 14 strains(l5.5%) on K 17 of K II, 26 strains(28.8%) on K 28 of K IV. 10 strains(11.1%) on K 32 of KV, 4 strains(4.4%) on K 39 of KV, 8 strains(8.8%) on K 42 of K VI, 2 strains(2.2%) on K 48 of K VII, 1 strain(1.1%) on K 50 of K II and 7 strains(7.7%) on K 55 of K VII, respectively. 5. V. parahaemolyticus was more frequently isolated from sea mud than sea water and various marine prdoucts in winter season. 6. There was no great difference as far as the distribution of V. parahaemolyticus concerned in Jeju, Keoje, Namhae, Yockji, Busan and Masan of the southern seas of Korea.

• Journal of Food Hygiene and Safety
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• v.14 no.3
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• pp.227-232
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• 1999

A total of 136 coliform bacteria isolated from spring water (112 strains) and ground water (24 strains), submitted to Seoul Health and Environmental Research Institute from June to July in 1997, were characterized biochemically and microbiologically. Colonical characteristics of each isolate were also noted, including color and texture on EMB agar. Among the 136 isolates, 50.7% were greenish metallic sheen color, 44.2% were pink and 5.1% were violet. The sixty four percent were smooth, 34.6% were mucoid and 0.7%. were rough. Twenty three bacterial species were identified by IMViC and API 20E test. Among the 136 coliform bacteria known to species, 39 isolates (28.6%) were Escherichia spp., 32 isolates (23.5%) were Klebsiella ssp., 30 isolates (22.1%) were Enterobacter spp., 19 isolates (14.0%) were Serratia spp., 6 isolates (4.4%) were Citrobacter spp., 4 isolates (3.0%) were Kluyvera spp. and 7 isolates (5.1%) were other bacterial species. Strains, which were gas-positive in lactose broth but gas-negative in Kligler Iron Agar were Ent. intermedium, Ser. liquefaciens, Ser. marcescenes and Salmonella arizoae. Strains, which were H2S production were also Kleb. pneumoniae, Kleb. oxytoca, Kleb. ornithinolytica, Ent. sahazahii, Ent. cloacae, Ser. liquefaciens, Ser. fica ria, Cit. freundii and Sal. arizoae. In the present study, most of coliform isolated from spring and ground water were E. coli, Klebsiella spp. and Enterobacter spp. Since coliform with pink colony in EMB agar was isolated as frequent as coliform with greenish metallic sheen colony, coliform with pink colony should be considered as important colony. Our results suggested that new coliform strains may be emerging on the basis of biochemical and microbiological testes.

• Korean Journal of Microbiology
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• v.37 no.1
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• pp.9-14
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• 2001

In order to investigate the pathogenicity and development of differential identification technique in the Yersinia species and other entericbacteria, we isolated 5 strains of Y.pseudotuberculosis from spring water sites in Seoul. The biochemical characteristics of isolated strains revealed that indole, VP($25^{\circ}C$, $37^{\circ}C$), $H_2S$, phenylalanine, lysine, arginine, ornithine, gas from glucose, lactose, sucrose, sorbitol, oxidase and motility($37^{\circ}C$) were all negative and urease, glucose, mannitol, salicin, catalase and motility($25^{\circ}C$) were all positive. To detect the causative agent of pseudotuberculosis(Y.pseudotuberculosis), we carried out a study using a PCR with inv primers complementary to the pathogenic region and found that all strains were positive, this revealed that strains from spring waters were pathogenic. Also 16S rDNA for total 5 strains of Y. pseudotuberculosis were amplified and a stretch of approximately 1,450 nucleotides were sequenced and analyzed. The 16S rDNA nucleotide sequence homologies among Yersinia species ranged 97.5% to 100% and between Y.pseudotuberculosis and other entericbacteria they ranged 93.0% to 95.1%. The Phylogenetic tree generated from the sequence analysis of the 16S rDNA gene showed 3 coherent clusters that could be separated into Y.pseudotuberculsis strains, some Yersinia species strains and other entericbacteria strains.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.3
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• pp.218-225
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• 2023

An agrivoltaic system (AVS) is a combined system that generates power through photovoltaic panels (PVPs) installed above a field where a crop is cultivated. Although soil moisture is an important limiting factor for open-field crop production, particularly during spring season in Korea, it is not well considered in the utilization of AVS. Indeed, the application of water-energy-food nexus on the AVS should be necessary. In this study, the changes of soil moisture and temperature under the AVS was investigated in fallow paddy field during spring season. The AVS that has partial shading condition by PV panels was decreased soil temperature and increased soil moisture compared to open-field. Furthermore, the maximum of the change in soil moisture to the change in soil temperature had a negative correlation both on open-field and AVS under wet condition. It represents that the micro-climate under the AVS is in energy-limited condition. The open-field of relatively high soil temperature was in water-limited condition. The different behavior of soil moisture on the AVS should be considered for the sustainable agricultural system as related to water-energy-food nexus.

• Korean Journal of Ecology and Environment
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• v.55 no.4
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• pp.320-329
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• 2022

Urban areas in watersheds increase the impervious surface, and agricultural areas deteriorate the water quality of rivers due to the use of fertilizers. As such, anthropogenic land use affects the type, intensity and quantity of land use and is closely related to the amount of substances and nutrients discharged to nearby streams. Riparian vegetation reduce the concentration of pollutants entering the watershed and mitigate the negative impacts of land use on rivers. This study analyzes the data through correlation analysis and regression analysis through point data measured twice a year in spring and autumn in 21 selected damaged tributary rivers within the Han River area, and then uses a structural equation model to determine the area land use. In the negative impact on water quality, the mitigation effect of riparian vegetation was estimated. As a result of the correlation analysis, the correlation between the agricultural area and water quality was stronger than that of the urban area, and the area ratio of riparian vegetation showed a negative correlation with water quality. As a result of the regression analysis, it was found that agricultural areas had a negative effect on water quality in all models, but the results were not statistically significant in the case of urban areas. As a result of the model estimated through the structural equation, BOD, COD, TN, and TP showed a mitigation effect due to the accumulation effect of river water quality through riparian vegetation in agricultural areas, but the effect of riparian vegetation through riparian vegetation was found in urban areas. There was no These results were interpreted as having a fairly low distribution rate in urban areas, and in the case of the study area, there was no impact due to riparian forests due to the form of scattered and distributed settlements rather than high-density urbanized areas. The results of this study were judged to be unreasonable to generalize by analyzing the rivers where most of the agricultural areas are distributed, and a follow-up to establish a structural equation model by expanding the watershed variables in urban areas and encompassing the variables of various factors affecting water quality research is required.