• The Korean Journal of Emergency Medical Services
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• v.8 no.1
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• pp.87-104
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• 2004

This study selected the fifth and sixth graders of elementary school in Jeollanamdo who can express their opinions of safety consciousness and understand the items of questionnaire as the population. It selected 10 elementary schools under the supervision of Jeonnam Board of Education and sampled 700 students randomly from 2-3 classes in the 5th and the 6th grade. One preliminary survey was conducted to revise and complement the contents and forms of questionnaire with 70 students of a school from Apr. 1 to 6, 2004 and this study was conducted from Apr. 10 to 30, 2004. Data of this study were collected by explaining the purport of study to subjects after obtaining approval of principal and teacher of the school and distributing questionnaires. Total 700 questionnaires were distributed and 681 were collected (97%) and 602 were used for final analysis except 79 lacking responses. The results of this study are as follows. According to demographical characteristics of subjects, 'male' students were 302(50.%) and 'female' students were 300(49.8%) by sex and 'the 5th graders' were 285(47.3%) and 'the 6th graders' were 317(52.7%) in grade distribution. Residents at 'apartment house' were 406(67.4%) in residence type, 'going to school by foot' was 477 students(79.2%), 'high school graduates' were 297(49.3%) in fathers' education, 'high school graduates' were 366 (60.8%) in mothers' education, 'professional and office workers' were 231(38.4%) in fathers' job, 'full-time workers' were 283(47.0%) in mothers' job, and the number of siblings was one except myself in 343 students(57.0%). Respondents on the level of class showing 'good' were 340(56.5%) and those on the degree of adaptation to school life showing 'active' were 349(58.0%). On the characteristics related to safety education, 360(59.8%) responded it was 'very necessary', on the frequency of safety education at school for last one year, 339(56.3%) responded they had 'once or twice', on the frequency of safety education by parents, 279(46.3%) responded they 'often' had it, on the level of safety practice by parents, 347(57.6%) responded they practiced it 'frequently', on the source of knowledge of safety, 223(37.0%) responded they got it from 'parents, siblings and relatives', on the degree of recognizing the need of safety education textbooks, 295(38.5%) responded 'it was needed', on the recognition of necessity of teacher for safety education, 271(45.0%) answered it was very necessary', and on the recognition of qualification of teacher for safety education, 370(61.5%) answered it was 'paramedic'. The mean score of safety consciousness of subjects was 2.72 (SD. 21) of full score 3, having high score over mean score. According to each area, the area showing the highest safety consciousness was safety of fire(2.83), followed by home safety(2.76) and first-aid treatment(2.76), traffic safety(2.71), play and leisure safety(2.66) and school safety(2.56). Items showing statistical differences in the degree of safety consciousness according to demographical characteristics were sex(t=-3.11, p=.002), education(t=2.33, p=.021) and number of siblings(F=3.729, p=.011). In the difference of safety consciousness between both sexes, 'female' students(2.75) showed higher safety consciousness than 'male' students (2.69), and the former also showed higher safety consciousness than the latter in all six areas of school safety, play and leisure safety, traffic safety, fire safety, home safety and first-aid treatment, and there were statistical differences in the areas of play and leisure safety, traffic safety, fire safety and first-aid treatment. According to the differences of safety consciousness by grade, 'the fifth graders'(2.74) showed higher safety consciousness than 'the sixth graders'(2.70) and the former also showed higher safety consciousness than the latter in all six areas of school safety, play and leisure safety, traffic safety, fire safety, home safety and first-aid treatment, and there were statistical differences in the areas of fire safety and home safety. In the safety consciousness by the number of siblings, 'single son or daughter' (2.78) was highest and their safety consciousness was also highest in all six areas of school safety, play and leisure safety, traffic safety, fire safety, home safety and first-aid treatment, and there were statistical differences in the areas of school safety, fire safety and home safety, There were statistically remarkable differences in degree of adaptation to school life (F=15.349, p=.000) and perceived schooling level(F=9.552, p=.000). According to the degree of safety consciousness related to characteristics of safety education, there were statistical differences at the degree of recognizing the need of safety education(F=9.797, p=.000), degree of safety education at school(F=2.595, p=.006), degree of safety education by parents(F=12.709, p=.000), degree of practicing safety by parents(F=17.579, p=.000), source of knowledge of safety education (F=2,715, p=.044), necessity of safety education textbooks(F=3.972, p=.008), need of safety teacher(F=4.137, p=.006) and qualification standard of safety teacher(F=3.016, p=.029).

• Korean Journal of Weed Science
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• v.30 no.2
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• pp.68-83
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• 2010

Weedy rice (Oryza sativa L.) occurred sympatrically with other weeds and the rice crop in Malaysian rice granaries. We conducted field surveys in 2006-2008 seasons in 7 farm blocks of Selangor's North West Project, Malaysia to enlist the new biotypes of weedy rice (NBWR) and assess their spatio-temporal pattern of distribution based on quantitative and dispersion indices. No less than 16 accessions of NBWR were identified based on their special traits, viz. panicle type, pericarp colour, presence or absence of awn, seed type and degree of grain shattering. The NBWR accessions exhibited a combination of morphological traits from open panicle, grain with awns, red pericarp, short grain type, and degrees of grain shattering. Others mimic commercial rices with close panicle, awnless grains, white pericarp, long or short grain-type. Invariably, the NBWRs mimic and stand as tall as cultivated rice namely MR219, MR220, or MR235 and these NBWR accessions stand among equals morphologically vis-a-vis the commercial rice varieties. Most accessions displayed varying degrees of grain shattering in excess of 50%, except Acc9 and Acc12. The seasonal dynamics of on the prevalence of dominant NBWR accessions were also displaying significant differences among farm blocks. While Bagan Terap farm block, for example, did not record any measurable changes in the dominant NBWR accessions over seasons, the Sungai Leman farm block recorded measurable season-mediated changes in the dominant NBWR accessions. Sungai Leman started with NBWR Acc3, Acc4, Acc5, Acc7, Acc8, and Acc12 in season 1 of 2006/2007, but no measurable records of Acc3 and Acc5 were shown in season 2 of 2007. In season 3 of 2007/2008, only Acc8 and Acc12 prevailed in the farm block. In Sawah Sempadan farm block, season 3 of 2007/2008 showed much reduced prevalence of NBWRs leaving only Acc8 and Acc12. Most accessions registered clump or under-dispersed spatial distribution pattern based on quantitative indices: variance-to-mean ratio (VMR) and Lloyd's patchiness values. The dynamics on the extent of infestation and prevalence of dominant NBWR accessions registered both season- and farm-block mediated differences. Most accessions showed VMR >1 thus indicative of having a clump or clustered spatial distribution, as exemplified by Acc3, Acc4, Acc7, Acc8 and Acc12 in all farm blocks throughout three seasons. Some accessions have either random or uniform distribution in a few farm blocks. The Acc8 has the highest population counts based on important value index, followed by Acc12, and both were the most dominant accession while Sawah Sempadan was the worst farm block infested by NBWR compared to other farm blocks. These results were discussed in relation with the current agronomic and weed management practices, water availability and extension services in the granary.

• Journal of Ecology and Environment
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• v.45 no.4
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• pp.277-286
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• 2021

Background: As trade increases, the influx of various alien species and their spread to new regions are prevalent and no longer a special problem. Anthropogenic activities and climate changes have made the distribution of alien species out of their native range common. As a result, alien species can be easily found anywhere, and they have nothing but only a few differences in intensity. The prevalent distribution of alien species adversely affects the ecosystem, and a strategic management plan must be established to control them effectively. To this end, hot spots and cold spots were analyzed according to the degree of distribution of invasive alien plants, and major environmental factors related to hot spots were found. We analyzed the 10,287 distribution points of 126 species of alien plants collected through the national survey of alien species by the hierarchical model of species communities (HMSC) framework. Results: The explanatory and fourfold cross-validation predictive power of the model were 0.91 and 0.75 as AUC values, respectively. The hot spots of invasive plants were found in the Seoul metropolitan area, Daegu metropolitan city, Chungcheongbuk-do Province, southwest shore, and Jeju island. Generally, the hot spots were found where the higher maximum temperature of summer, precipitation of winter, and road density are observed, but temperature seasonality, annual temperature range, precipitation of the summer, and distance to river and sea were negatively related to the hot spots. According to the model, the functional traits accounted for 55% of the variance explained by the environmental factors. The species with higher specific leaf areas were more found where temperature seasonality was low. Taller species preferred the bigger annual temperature range. The heavier seed mass was only preferred when the max temperature of summer exceeded 29 ℃. Conclusions: In this study, hot spots were places where 2.1 times more alien plants were distributed on average than non-hot spots (33.5 vs 15.7 species). The hot spots of invasive plants were expected to appear in less stressful climate conditions, such as low fluctuation of temperature and precipitation. Also, the disturbance by anthropogenic factors or water flow had positive influences on the hot spots. These results were consistent with the previous reports about the ruderal or competitive strategies of invasive plants instead of the stress-tolerant strategy. The functional traits are closely related to the ecological strategies of plants by shaping the response of species to various environmental filters, and our result confirmed this. Therefore, in order to effectively control alien plants, it is judged that the occurrence of disturbed sites in which alien plants can grow in large quantities is minimized, and the river management of waterfronts is required.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.E2
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• pp.85-95
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• 2002

Hydrogen peroxide and methyl hydroperoxide were measured over the northwestern Pacific Ocean during NASA's PEM (Pacific Exploratory Mission) -West. The first experiment (PEM -West A) was conducted in the fall of 1991 and PEM-West B in the early spring of 1994. Hydroperoxide data were obtained on board the NASA DC -8 aircraft through the entire depth of the troposphere. Average concentrations of both H$_2$O$_2$and CH$_3$OOH were higher during PEM -West A than B. The seasonal difference in hydroperoxide distribution was determined by the degree of photochemical activities and the strength and location of jetstream, which led to extensive and rapid continental outflow during the PEM-West B. While for H$_2$O$_2$distribution, a longitudinal gradient was more apparent than a latitudinal gradient, it was opposite for the CH$_3$OOH distribution. The longitudinal gradient indicates the proximity to the anthropogenic sources from the Asian continent, but the latitudinal gradient reflects photochemical activity. During PEM -West B, the ratio of C$_2$H$_2$/CO, a tracer for continental emission was raised and high concentrations of H$_2$O$_2$were associated with high ratios. The flux of hydroperoxide toward the North Pacific was also enhanced in the early spring. The eastward fluxes of H$_2$O$_2$ were 9% and 17% of the average photochemical production over the Pacific Basin between 140°E and 130°W during PEM-West A and B, respectively. For CH$_3$OOH, these ratios were 8% and 13%. Considering the lifetime of hydroperoxide and the rapid transport of pollutants, the export of hydroperoxide with other oxidants would have a significant influence on oxidant cycles over the North Pacific during winter/spring.

• Journal of Environmental Science International
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• v.9 no.4
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• pp.285-294
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• 2000

Butyltin compounds (BTs) in seawater, sediments and organisms (Thais clavigera, Liolophura japonica and Cellana nigrolineata), were quantitatively determined to evaluate their distribution inside Songsan Harbor of Cheju Island. In addition, imposex in T. clavigera was used to assess the effect on organisms of BTs. Analysis of the samples collected in seawater, sediments (March, June and August) and organisms (May, July and August) in 1998, confirmed the contamination of BTs in the aquatic environment inside Songsan Harbor. The main BTs species in seawater and sediments was monobutyltin (MBT), tributyltin (TBT), respectively, irrespective of survey time. In oranisms, TBT and dibutyltin (DBT) were detected in similar concentrations for T. clavigera and L. japonica, but for C nigrolineata, DBt concentration was the highest. TBT, the most toxic to aquatic organisms among BTs, was found at concentrations which were sufficient to have a serious effect on the sensitive organisms upon chronic exposure, The relatively high correlations (r>0.83) between BTs indicated that DBT and MBT were mainly degraded from TBT based on antifouling paint and their sources were negligible. The sedimentary organic matters did not have influence on the distribution of BTs in marine environment, and lipid content in T. clavigera did not show a correlation with TBT concentrations. The rate of occurrence of imposex in T. clavigera was 100%, and the relative penis length index (RPLI) and the relative penis size index (RPSI) which represent the degree of imposex were 79.7%, 58.1%, respectively. Measurement of imposex in T. clavigera was expected to be a very helpful tool for preliminary survey of BTs prior to trace analysis of BTs.

• Journal of Ecology and Environment
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• v.38 no.4
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• pp.405-413
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• 2015

We classified the streamside plant community by phyto-sociological method and analyzed the relationship between environment factors and vegetation structure by using the classification and ordination method. We found that twenty one plant communities were classified according to dominant species at the natural streamside valley forest with surveying the 65 quadrats (10 m × 10 m). From the survey results, the hardwood plant communities were classified as streamside valley forest and the softwood plant communities as riparian forest according to the degree of flooding. The valley forest had a distribution of 17 plant communities which was 65% (42 quadrats) of 65 quadrats: Maackia amurensis community, Betula davurica community, Quercus variabilis community, Pinus densiflora community, Q. serrata community, Prunus sargentii community, and Meliosma oldhamii community etc. The riparian forest had a distribution of four plant communities which was 35% (23 quadrats) of 65 quadrats: Salix koreensis community, S. rorida community, S. purpurea var. japonica community, and S. glandulosa community, etc. From the two-way indicator species analysis (TWINSPAN) analysis, we found indicator species Oplismenus undulatifolius and Lindera obtusiloba for the streamside valley forest and Humulus japonicus, Phragmites japonica, and S. koreensis for the riparian forest. From the results of the canonical correspondence analysis (CCA), coordinates, altitude, and stream structure showed low correlation to the distribution of the plant community. Therefore, it seemed that valley forest and riparian forest were distinguished by the stream gradient and waterway width which determined by the stream water level.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.5
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• pp.110-120
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• 2009

The hipped roof on the research building, which was constructed 51.9m above sea level on a hillock by Korea National University of Education in June 1999, is composed of four inclined planes which are 12m in breadth, 8m in length and have a 30 degree gradient. For the roof vegetation, the yellow earth collected from around the building was laid on top. It was designed to supply the soil on the slope with water for a considerable period by making rainfall pool at the edges. In order to prevent the soil on the slope from being swept away, 31 sorts of grass seeds were imported from Germany and sown in the soil. At the present day, 10 years after the seeds began to sprout and inhabit the settled slope, 30 individual plant species were identified in the period between April 2008 and March 2009. Out of 31 species were seeded on the slanted, soiled roof, only 8 were still alive. It was confirmed that the Artemisia Princeps var, Chrysantheum, Prunella Vulgaris and Lespedeza Cuneata have been the major species inhabiting the east, west, south and north inclined planes respectively. The Phragmites Communis was inhabiting the edge of the roof where the water supply was adequate, while the Dianthus Barbatus was primarily inhabiting the south-east side of the roof. As a whole, 26 identifiable plants and 4 unidentified plants were observed on the inclined planes of the hipped roof. In consideration of the plant distribution on the slope, it was confirmed that the selection of seeds may have had an effect on the slope vegetation. As for the yellow earth laid on the roof, it was discovered that about 2~3cm thickness around the ridge was swept away, but the rest of the slope was in relatively good condition. Accordingly, it has been proven that vegetations can be applied to hipped roofs by using ordinary plants without any special structural measures.