• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.265-273
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• 1986

The marine algal communities of Yonhwa-do at the southern coast of Korea were investigated in aspects to quantitative analysis of their structure and dynamics. As a result, 114 species, including 2 blue-green, 69 red, 25 brown and 18 green algae, were identified. The R/P value(2.8) is higher than that of other regions of the southern coast of Korea. Sheet and filamentous groups of the functional groups of algae showed higher composition rate in spring and summer than in autumn and winter, but coarsely branched and thick leathery groups showed an opposite tendency. Cluster analysis based on species presence suggested the existence of 5 distinct groups in spring, but 3 groups in the other seasons. The species exhibiting important value above 20 were as follows: Porphyra suborbiculata, Corallina pilulifera, Hizikia fusiforme, Sargassum thunbergii, Undaria pinnatifida, Ishige okamurai, Chondria crassicaulis, and crustose coralline algae. The coverage of algal communities composed only of crustose coralline algal complex was higher than that of other algal complex, but occurrence frequency of these two communities was indifferent. It is suggested that the occurrence in high quantity of crustose coralline algae from this area is related to grazing by herbivorous animals.

• Journal of Korean Society of Forest Science
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• v.85 no.2
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• pp.288-299
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• 1996

This is the basic study to investigate the amount of transpirational water loss in thrifty mature Quercus mongolica stand by the heat pulse method. The differences of heat pulse velocity by direction and depth, differences of heat pulse velocity by dominant, codominant and suppressed trees, diurnal changes of heat pulse velocity due to the change of leaf water potential, vapor pressure deficit and radiation, and sap flow path way in sapwood by dye penetration were measured in stems. Finally the amounts of daily and annual transpiration in stand were calculated by the heat pulse velocity. The results obtained were summarized as follows : 1. Relationship between heat pulse velocity(V) and sap flow rate(SFR) was obtained as a equation of SFR=1.37V. 2. The sap flow rate was high in the order of dominant, codominant, and suppressed trees. The daily heat pulse velocity changed with radiation, temperature and vapor pressure deficit. 3. The heat pulse velocity showed the similar diurnal variation as the leaf water potential change. 4. The heat pulse velocity showed the highest value in May(4.0cm/hr in average), the lowest one in July(2.9cm/hr in average). 5. The heat pulse velocity in the same stem presented the highest value in the northern direction, medium in western, and the lowest in southern and eastern. 6. The heat pulse velocity in stem was highest in 0.5cm, medium in 1.0cm, and lowest in 1.5cm depth from the surface of stem. 7. The sap flow path way in stem showed sectorial straight ascent pattern in four sample trees. 8. The amount of sap flow(SF) was presented as a equation of $SF=1.37A{\cdot}V$(A: the cross-sectional area of sapwood, V: heat pulse velocity), and especially SF was larger in dominant tree than codominant and suppressed trees. 9. The amount of daily transpiration was 5.6ton/ha/day, and its composition ratio was 72% at day and 28% at night. 10. The amount of stand transpiration per month was largest in May(168ton/ha/month), lowest in July(125ton/ha/month). The amount of stand transpiration per year was 839ton/ha/year.

• Korean Journal of Environment and Ecology
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• v.33 no.5
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• pp.506-514
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• 2019

Unlike natural ecosystems, the urban ecosystem proVides an interdependent enVironment in which wild organisms and urban people co-exist. Hornets (genus Vespa) appearing in urban green and parks haVe a positiVe effect on urban ecosystems, but they also cause ecosystem disserVices that cause physical and psychological discomforts to the urban people. Children's parks, for example, are Very popular among children and residents for easy accessibility, and hornets also use them as bases and habitats. HoweVer, there is still a lack of spatial analysis of habitats and appearance characteristics of hornets in children's parks. This study installed hornet traps in 27 children's parks in Cheonan from April to NoVember 2018 in consideration of the life cycle of hornets. We captured a total of fiVe Vespa species (Vespa crabro, V. analis, V. mandarinia, V. ducalis, and V. Velutina) for 32 weeks and analyzed the emergence of hornets in relation to the composition of seasonal characteristics, species characteristics, and enVironmental spatial information. We captured a total of 818 hornets during the study period. They included 290 V. analis (35.4%), 260 V. crabro (31.8%), 100 V. ducalis (12.1%), 87 V. mandaninia (10.6%), and 81 V. Velutina(9.9%). Most of the hornets showed a common feature that queen hornets were largely captured in May through June after they awake from hibernation, and the number of caught hornets decreased sharply beginning in mid-June, which was the cooperatiVe period. HoweVer, V. Velutina showed a seasonal specificity that more than 80% were captured beginning in the third week of October when other hornet species had already entered a decline phase. The analysis of the number of hornets caught in each spot in children's parks showed significant difference among the spots as 363 hornets (44.3%) were captured in top children's parks, and 35 hornets (4%) were captured in bottom children's parks. In particular, the mean NDVI (Normalized difference Vegetation index) of the top six children's parks was 0.79, and that of the bottom six children's parks was 0.38 (t=2.67*, *=p<0.05), indicating a significant difference. The frequency of capturing hornets was high when the ground around the children's parks was grass or bare land. This study is meaningful as a reference study that confirms the ecological characteristics of hornets appearing in green and parks in the city. We expect it to be a foundation for effectiVe urban green area management in the future.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.31 no.3
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• pp.83-94
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• 2013

The purpose of this study is to offer basic data about prototype conservation of the Orijangnim, natural monument No. 404. For this study, March to August 2010, was a literature surveys and field research, and based on this, the Delphi survey of local residents and experts meeting were diagnosed with forest back ground, spatial extent, in the form of forests, flora and vegetation of the surrounding area, so examined closely the original form. Range of the Orijangnim was presumed from Jacheon middle school entrance($N36^{\circ}05^{\prime}59.9^{{\prime}{\prime}}/E128^{\circ}54^{\prime}32.9^{{\prime}{\prime}}$) to Odong of Hwabukmyeon village entrance($N36^{\circ}05^{\prime}31.0^{{\prime}{\prime}}/E128^{\circ}54^{\prime}32.5^{{\prime}{\prime}}$). The Orijangnim in the original form of the existing forest surrounding the village along gohyeon river going back a long S-shaped about 2km is considered. The investigated vascular plants consist of total 198 taxa : 2 forms, 20 varieties, 179 species, 152 Genera, 72 Families. Most of the 60 kinds of large land plants lots of whole plants accounted for 33.3%. A main vegetation of the Orijangnim have been distributed 473 objects of 21 species, and evergreen conifers is 19% to 92 objects, on the other hand, deciduous broadleaf tree is 79% to 373 objects, so the Orijangnim can be maxed forest that deciduous broadleaf tree is dominant. When consider the composition purpose of forest, environment of location, tree size, surrounding flora and vegetation, because an original vegetation of Orijangnim is suggested Zelkova serrata, Salix glandulosa, Celtis sinensis Pers., Quercus variabilis, Quercus acutissima , Sophora japonica L., Cornus walteri Wanger. we must restore around such species of tree. Cedrus deodara (Roxb.) Loudon, Chaenomeles sinensis, Prunus yedoensis Matsum., Ginkgo biloba , Pinus thunbergii Parl., Populus tomentiglandulosa T. Lee is considered to have been planted in the last.

• Journal of Preventive Medicine and Public Health
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• v.18 no.1
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• pp.73-82
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• 1985

This study was conducted to evaluate nutritional status with the analysis of the factors which might influence on the prevalent condition of nutrients-intake. 373 persons who are above 60 years old in Chung-Gu, Seoul were surveyed from March 15 to March 30 in 1985. Results were as follows ; 1. General Characteristics 1) Male respondents among the entire respondents comprised 54.3% and female respondents comprised 45.7%. As for age, male and female respondents comprised 55.0% and 37.2% respectively. 2) As for the educational level of the respondents, illiteracy was 49.9% which was the highest. and those who graduated elementary school was 28.1% which was the second highest. And as for the comparison of the education of the male and female respondents, the educational level of male respondents was much higher than that of female respondents. 3) As for the final occupation of the respondents, those who were engaged in commerce comprised 30.8% which was the highest rate, and who were engaged in agriculture comprised 20.1% which was the second highest rate. And those who were engaged in labor comprised 12.3%. 2. The State of Nutrients-intake The energy of the male respondents was 61.4% of RDA and the protein was nothing but 66.8% of RDA. Except vitamin A, vitamin $B_1$ and niacin, calcium, iron, vitamin $B_2$, vitamin C were lower than RDA (the range: $67.5%{\sim}97.3%$). The energy of the female respondents was 70.0% of RDA and the protein was 58.8% which were lower than RDA. Except vitamin A and vitamin $B_1$, calcium, iron, vitamin $B_2$ vitamin C, niacin were lower than RDA (the range: $68.2%{\sim}98.9%$). 3. The various factors related to nutrients-intake 1) The composition of family and the food environment those who were living with their spouses comprised 44.8% which was the highest rate, and those who were living with their son's family comprised 33.5% which was the second highest rate and those who were living with their doughter's family comprised only 4.6%. Those who were living alone comprised 16.4%. The correlation with nutrient intake didn't show a clear relation. 2) Socio-economic state Those who said that they lacked in living expense comprised 32.7% and those who said that they lacked in pocket-money comprised 23.9%, The female respondents outnumbered the male respondents in lacking living expense or pocket-money. In the correlation with socio-economic, there was no striking relation with education level. However, it was shown that little relation in energy, fat in male and also fat and iron in female. The living expense and the satisfaction in pocket-money had also little relation with energy fat and vitamin C in male. 3) Nutrition knowledge and food habit (a) The state of nutrition knowledge and food habit In nutrition knowledge, those who scored less than 60 points were 32.9%, and those who scored more than 90 points were 21.0%. In food habit, those who scored less than 60 points were 26.5% and those who scored more than 80 points were 45%. (b) The corelation with nutrition knowledge and food habit In case of female respondents, nutrition knowledge had a little relation with the intake of cabohydrate, iron, and vitamin C. And we couldn't see a distinct phenomenon in food habit.

• Economic and Environmental Geology
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• v.34 no.6
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• pp.507-522
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• 2001

At the Tongyeong mine, quartz, rhodochrosite (kutnahorite), muscovite, illite, pyrite, galena, chalcopyrite. sphalerite, acanthite, and hessite are the principal vein minerals. They were deposited under epithermal conditions in two stages. Ore mineral assemblages and associated gangue phases in stage can be clearly divided into two general associations: an early cycle (band) that appeared with introduction of most of the sulfides and electrum, and a later cycle in which base metal and carbonate-bearing assemblages (mostly rhodochrosite) became dominant. Tellurides and some electrum occur as small rounded grains within subhedral-to euhedral pyrite or anhedral galena in stageII. Sulfide mineralization is zoned from pyrite to galena and sphalerite. We have used computer modeling to simulate formation of four stages of vein genesis. The reaction of a single fluid with andesite host rock at 28$0^{\circ}C$, isobaric cooling of a single fluid from 26$0^{\circ}C$ to 12$0^{\circ}C$, and boiling and mixing of a fluid with both decreasing pressure and temperature were studied using the CHILLER program. Calculations show that the precipitation of alteration minerals is due to fluid-andesite interaction as temperature drops. Speciation calculations confirm that the hydrothermal fluids with moderately high salinities and pH 5.7 (acid), were capable of transporting significant quantities of base metals. The abundance of gold in fluid depends critically on the ratio of total base metals and iron to sulfide in the aqueous phase because gold is transported as an Au(HS)$_2$- complex, which is sensitive to sulfide activity. Modeling results for Tongyeong mineralization show strong influence of shallow hydrogenic processes such as boiling and fluid mixing. The variable handing in stageII mineralization is best explained by maltiple boilings of hydrothermal fluid followed by lateral mixing of the fluid with overlying diluted, steam-heated ground water. The degree of similarity of calculated mineral assemblages and observed electrum composition and field relationships shows the utility of the numerical simulation method in identifying chemical processes that accompany boiling and mixing in Te-bearing Au-Ag system. This has been applied in models to narrow the search area for epithermal ores.

• The Korean Journal of Ecology
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• v.27 no.6 s.122
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• pp.325-333
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• 2004

Birds were censused to investigate the composition of landscape structure for bird diversity around Ulsan between May and November 2002. Associations with three main categories of habitat variables were evaluated: 1) amount and type of forest; 2) residual habitats not classified as forest or crops; 3) land-use variables. Cluster analysis of bird community shows the highest forest variables of $79.06\%$, and the others are residual habitat variables ($17.98\%$), land-use variables ($2.94\%$) in spring, and forest variables of $57.77\%$, land-use variables ($23.16\%$), residual habitat variables ($18.47\%$) in autumn, respectively. In Principal Component Analysis of a total of 196 sites, the populations are strongly correlated to Component I ($54.8\%$) based forest habitats and to Component II based on land-use. Species preferring sites were clearly separated with heterogenous forest along the first axis. In autumn, the populations are moderately correlated to Component I based land-use and to component II based forest habitats. Species preferring local habitats were also clearly separated. Fifty three species of 1,700 birds were recorded: Brown-eared Bulbul, Vinous-throated Parrotbill, Great Tit, Tree Sparrow and Black-billed Magpie accounted for over $60\%$ of the observed birds in spring and autumn. The important species were Brown-eared Bulbul, Vinous-throated Parrotbill, Great Tit and Tree Sparrow in spring and autumn. Four habitats in terms of their species richness were computed as follows: Wonhyosan has the highest an expected species number, $E[S_{59}]=19$. Moonsusan has the lowest expected species number, $E[S_{59}]=17$ in spring. In autumn, Kuenamsan has the highest expected species number, $E[S_{63}]=16$. Moonsusan has the lowest expected species number, $E[S_{63}]=12$. Pairwise similarity declined with increasing distance between recording site and recording site from Moonsusan-Wonhyosan (0.62), the same geographical regions clustered separately in a UPGMA cluster tree in spring, and in autumn from Moonsusan-ChungJoksan (0.53).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.1
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• pp.20-26
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• 2023

Fiber content in the storage roots of sweetpotato varies between different varieties. For examples, the high fiber content of certain types has a poor texture when steamed or roasted. This study was conducted to evaluate the optimal sieve mesh size for separating fibers, the chemical composition of fibers and differences in fiber content among different varieties. We found that the separated fiber content (dry weight) of mashed and steamed sweetpotato was higher after washing three times (143.3 mg/100 g) compared with that washed five times (128.4 mg/100 g). The Hogammi variety remained 85.9% of total fiber content at 10 mesh (2,000 ㎛) and 9.6% of total fiber content at 30 mesh (600 ㎛), and Jinyulmi remained 74.9 and 16.7% of total fiber content , respectively. Therefore, a 30 mesh sieve was considered the most suitable for fiber separation. Among the 10 studied cultivars, Jinhongmi showed the lowest amount of fiber (24.8 mg/100 g) and Hogammi had the highest amount (111.4 mg/100 g), which was 4.5 times larger than that of Jinhongmi. Cellulose, hemicellulose and lignin content of separated fibers showed no difference between the viscous-type Hogammi and powdery-type Jinyulmi varieties, with averages of 32.5, 22.3 and 29.6%, respectively. Correlation results using the Image J program showed a significant correlation between the distribution of the stained area and the fiber content (R = 0.74, p < 0.05). Staining distribution differed among varieties, suggesting that a simple fiber content test could be performed using the staining method on raw sweetpotato. These results provide useful information to help inform farmers on the fiber content of different sweetpotato varieties.

• Korean Journal of Ecology and Environment
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• v.55 no.1
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• pp.84-98
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• 2022

Estuary is important in terms of biodiversity because it has the characteristics of transition waters, created by the mixing of fresh- and seawater. The estuarine water circulation provides a variety of habitats with different environments by inducing gradients in the chemical and physical environment, such as water quality and river bed structure, which are ultimately the main factors influencing biological community composition. If the water circulation is interrupted, the loss of brackish areas and the interception of migration of biological communities will lead to changes in the spatial distribution of biodiversity. In this study, among the sites covered by the Estuary Aquatic Ecosystem Health Assessment, we selected study sites where changes in biodiversity can be assessed by spatial gradient from the upper reaches of the river to the lower estuarine area. The α-, γ- and β-diversity of diatom, benthic macroinvertebrates, and fish communities were calculated, and they were divided into open and closed estuary data and compared to determine the trends in biodiversity variation due to estuarine circulation. As results, all communities showed higher γ-diversity at open estuary sites. The benthic macroinvertebrate community showed a clear difference between open and closed estuaries in β-diversity, consequently the estuarine transects were considered as a factor that decreases spatial heterogeneity of their diversity among sites. The biodiversity trends analyzed in this study will be used to identify estuaries with low γ- and β-diversity by community, providing a useful resource for further mornitoring and management to maintain estuarine health.

• Korean Journal of Environment and Ecology
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• v.21 no.6
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• pp.536-543
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• 2007

This research was conducted every month from June 1994 until August 1996 with the aim to understand the ecosystem structure through the analysis of oribatid mite community structure in soil subsequent to environmental difference of its habitats located at northward & southward slopes adjacent to each other at an altitude of 1,000 meters of Mt.Jumbong, which is a natural reserved forest, remaining intact. There appeared a significant difference [t-test, p<0.06] in comparison of the number of the species and individuals of Oribatid mite species which were collected and identified at two survey areas. The mean density and the number of the species collected and identified at the northward slopes, and southward slopes were $99.2{\pm}17.6,\;234.2{\pm}62.6$ and $24.7{\pm}3.0,\;40.8{\pm}5.8$, respectively. Species diversity index(H') was higher at the southward slopes($3.09{\pm}0.11$) than at the northward slopes($2.71{\pm}0.13$). The population size of Oribatid mite species was found by the percentage of each species density as against the whole density and classified into dominant species, influent species, and recessive species according to the percentage; as a result, O. nova and Suctobelbella naginata was found to be a dominant species at both survey slopes while Trichogalumna nipponica was found to be a dominant species, at southward but it wasn't collected at the northward slopes at all. The feeding habit of the dominant species at two survey slopes was found to be microphytophagous- eating soil microbe. There appeared a conspicuous difference in compositions of the number of the species, individuals and dominant species at the southward/northward slopes adjoining each other at an attitude of 1,000 meters and less similarity between the two survey slopes. Conclusively, It was found that the heterogeneity of microhabitat has a great effect on Oribatid mite's community characteristics.