• Title/Summary/Keyword: DISTRIBUTIONAL AREA

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Distributional Ecology Of Planktonic Diatoms In The Strait Of Georgia, B. C.

  • Shim, Jae Hyung
    • 한국해양학회지
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    • v.12 no.1
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    • pp.13-32
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    • 1977
  • In order to determine the distributional ecology, and to investigate factors influencing these features, the diatom communities in plankton at depths of one, twenty-five, fifty, and seventy five meters in the area were studied and measured over a fifteen month of period. Measurements of environmental factors including temperature and salinity and algal nutrients such as phosphate, silicate, nitrate, and ammonia were also made at the same depths and locations. The results indicate that the size of diatom communities and the species population changes were heavily dependent upon to season and location parameters as well as nutrient concentrations and hydrographic factors. Major factors influencing population distributions varied with principal species responsible for dominant species and species sucession. Two distinct distributional patterns in total diatom crop were observed in the study area. Maximum standing crop observed during spring and/or summer were related to the concentration of nutrients available at the onset of the spring bloom on a large scale. On a small scale, however, the distributions of total diatom standing crops were significantly correlated with both season/location factors and with hydrographic parameters as well. Vertical stratification of diatoms was observed only in the presence of the thermocline in the water column. Within the study area there was some seasonal consistancy in the composition of the species groups. However, some species association in these environments may vary with the change of season.

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Vegetation Structure and Distributional Characteristics of Abies koreana Forests in Mt. Halla (한라산 구상나무림의 식생구조와 분포 특성)

  • Song, Kuk-Man;Kim, Chan-Soo;Koh, Jung-Goon;Kang, Chang-Hun;Kim, Moon-Hong
    • Journal of Environmental Science International
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    • v.19 no.4
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    • pp.415-425
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    • 2010
  • The purpose of the present study was to analyze the vegetation structure and distributional characteristics of Abies koreana forests in Mt. Halla, and to provide basicdata for an ecological study on Abies koreana in Mt. Halla. The results of the analysis showed that the mean importance percentage(M.I.P,) of Abies koreana in the Youngsil and Bangaeoreum and the Azalea field were 28.3%, 23.6%, and 46.4%, respectively. The ratios of DBH (diameter at breast height) to height were similar in all region, except in the Azalea field, where Abies koreana of various ages, both young and old, were found. The species diversity (H) of the upper and lower layers in the Youngsil and Bangaeoreum and in the Azalea field were 0.625 and 0.810, 0.731 and 0.848, and 0.342 and 0.757, respectively. A total of 52 community were distributed at locations higher than 1,300m above sea level. The proportions of each community in the whole Abies koreana forest were 56.5%(Azalea field), 11.0% (Youngsil trail at 1,550-1,650 m above sea level), and 8.1%(Janggumok and Kundurewat region). The total area of the Abies koreana forest was calculated to be 795.3ha by combining all the areas of each community. An Abies koreana forest with the largest area was found at locations 1,500-1,600 m above sea level, taking up 38.8% of the total Abies koreana forest area. For the slopes of the distributional area of Abies koreana, 46.1%(highest proportion) of the total area was $10\sim25^{\circ}$, and for the azimuth of the distributional area, 17.4%(the highest proportion) of the total area was $0-45^{\circ}$. The vegetation structure showed large differences between areas. It was found, however, that the distribution was mostly in the areas with a relatively gentle slope. It is suggested that research be done to forecast the possible changes in the differences in the vegetation structures between different areas caused by climate changes. In addition, there is a need to monitor the Abies koreana and alpine plants in the subalpine zones of Mt. Halla, which are sensitive to climate change, to obtain the basic data that are necessary for the protection and maintenance of the ecosystem.

Geomorphic development and distributional system of marine terrace in the eastern part of Seopo-myeon, Sacheon-si, Gyeongnam Province (경남 사천시 서포면 동쪽 해안단구 지형 발달과 분포 체계)

  • Yoon, Soon-Ock;Kang, Bong;Park, Chung-Sun;Hwang, Sangill
    • Journal of the Korean association of regional geographers
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    • v.22 no.4
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    • pp.875-886
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    • 2016
  • The eastern coast of Seopo-myeon, Sancheon-si in the South Coast is a bay almost completely separated from open sea by Changseon and Namhae Islands. Marine terraces in this area can be classified into geomorphic surfaces with elevations of 10~12m, 15~18m, 20~24m, 25~28m, 30~33m, 35~38m, 40~45m, 45~50m and 54m. This marine terrace system is similar to the Boryeong area in the West Coast. The geomorphic surfaces distribute along ridges and show relatively small areas. The young and old surfaces show a mixed distributional pattern. This distributional pattern contrasts to the East Coast where the oldest surface farthest from the coastline is parallel to the coast and age of the surfaces increases with a distance from the coast. These seem to result in high energy waves by typhoon that developed wave-cut platform on hill areas with relatively complex relief in a short time.

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Distributional changes in Physicians' Medical Care Expenses from the National Health Insurance and its Determinants After the Separation of Prescription and Dispensing (의약분업 전후 의원의 건강보험 진료비 분포변화 및 결정요인분석)

  • Lee Ae Kyoung;Jeong Hyun Jin
    • Health Policy and Management
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    • v.14 no.3
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    • pp.20-44
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    • 2004
  • The National Health Insurance Expenditure has been increased rapidly since the introduction of the separation of prescription and dispensing in 2000, and this trend of rapid growth in overall spendings rate has been observed predominantly among medical practitioners. This study was conducted to investigate the growth rate and distributional changes in private medical practitioners' expenses from 1999 to 2002 and its determinants using the National Health Insurance claims data. The total increasing rate of all medical practitioners' expenditure paid by the National Health Insurance between 1999 and 2002 was $41.71\%$, which exceeding that of general hospitals by $20\%$p. But the income distribution among each practitioner was improved as the changes in Gini coefficient(from 0.40 to 0.38) and decile distribution ratio(from 0.25 to 0.29) during the same period showed. However, this improvement in distributional patterns is not enough since even in 2002 it turned out that the highest $10\%$ income group earned 33times more than the lowest $10\%$ income group did. Also, higher Gini coefficient was observed in larger cities and some department like plastic surgery, obstetrics and gynecology. The major causes of this differentials in medical practitioners' expenses were factors related to medical demand like proportion of old population, residential economic status in a given area. In addition, providers' economic incentives also played an important role in determining their income distribution. The large income differentials among physicians may imply a skewed distribution of patients and thus long waiting time, inefficient utilization of resources and potential inadequate quality of care. In this sense, unreasonable distributional gaps should be reduced, so effective measures as well as ongoing monitoring would be necessary to correct current distributional problems.

Distributional Patterns of Understory Vegetation at Mt. Geumdae's Protected Area for Forest Genetic Resources (금대봉 산림유전자원보호림의 하층식생 분포양상)

  • Chun, Seung-Hoon;Lee, Hyung-Sook;Lim, Jong-Hwan
    • Journal of Korean Society of Forest Science
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    • v.98 no.3
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    • pp.339-350
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    • 2009
  • This study was carried out to investigate distributional condition of rare plants and useful plant resources, and to verify distributional patterns of understory vegetation associated with the upper layer's vegetation structure. Total 59 families, 160 genera, 218 kinds of vascular plants were identified at the study site including 6 rare plants designated by Korea Forest Service (Lloydia triflora Bak., Trillium kamtschaticum Pall., Lilium distichum Nakai, Anemone koraiensis Nakai, Iris odaesanensis Y.N. Lee, Viola diamantica Nakai). Twenty three species of useful plant resources were also identified at the site; 8 of them showed clustered distributions and the others were prone to scatter. Actual vegetation of this study area consisted of one natural community dominated by Quercus mongolica Fisch. and three disturbed communities of Larix kaempferi (Lamb.) Carriere, Abies holophylla Max. and/or a herbaceous vegetation resulting from forest removal and strong wind of mountain top. This classification was strongly supported by cluster analysis based on the surveyed plot data. Distributional patterns of understory vegetation within forest stand were somewhat related to overstory vegetation structure, but showed a different tendency according to site condition, species composition, and competitive pressure among understory vegetation. Therefore, in order to protect the important understory components as forest genetic resources, forest treatments such as density control of overstory should be implanted based on understanding of impact on understory's dynamics and growing condition.

Application of Topographic Index Calculation Algorithm considering Topographic Properties (지형적 특성을 고려한 지형지수 산정 알고리즘에 관한 연구)

  • Lee, Ji-Yeong;Kim, Sang-Hyeon
    • Journal of Korea Water Resources Association
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    • v.33 no.3
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    • pp.279-288
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    • 2000
  • The impact of land slope to the degree of flow divergence was considered employing distributional applications of slope exponents in the now directlOn algoriUnns. Lmear, exponential and ]X)wer law of distributional functIons were employed to address the variation of slope exponents m a terrain analysis. Dongok subwatershed at Wichun test watershed was selected as a study area. Digital Elevation Models of 20m, 30m, 40m and 50m grid size were made to perfonn the analysis. Various calcualtion methodologies of topographic index and the impact of grid sizes were investigated in terms of statistical and spatial aspects. DIstributional applications of slope e.xponents made it possible to represent the flow divergence and convergence about the ten-ain characteristics. The Monte~Carlo method was used to simulate six runoff events to check the impact of topographic factor in the runoff simulation.

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The Biology of the Pelagic Amphipod, Primno macropa Guer., in the Western North Pacific: 2. Geographical Distribution and Vertical Distributional Pattern

  • Yoo, Kwang-Il
    • The Korean Journal of Zoology
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    • v.15 no.2
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    • pp.87-91
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    • 1972
  • For the geographical distribution of Primno macropa it was distributed over all stations investigated, except surface tow in East China Sea, through all seasons. It is believed that this species is most cosmopolitan species in the western North Pacific. Veritical distributional range of P. macropa indicates at depths from surface to more than 1,500m and most deeper recored for the vertical occurrence was obtained from depth of 1,650-2,220m in Station 229 $(34^\\circ 44.3'N, 140^\\circ 04.4'E)$, off Nojima-Zaki, Central Japan. For the vertical distributional and migrational pattern it is a typical diurnal migrant in the western North Pacific; at depths from 100m to 500m at night and 400m to 700m at day in Oyashio population, and from surface to 200m at night and from 100m to 300m at day in Kuroshio population. In Kuroshio area, the population of P. macropa was distributed in somewhat shallower layers than in Oyashio area and it is suggested that the populations is different in region and season according to their stages consisting the population.

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Stochastic Dominance and Distributional Inequality (추계적 우세법칙과 분포의 비상등성)

  • Lee, Dae-Joo
    • IE interfaces
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    • v.6 no.2
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    • pp.151-169
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    • 1993
  • In this research, we proposed "coefficient of inequality" as a measure of distributional inequality for an alternative, which is defined as the area between the diagonal line from 0 to 1 and the Lorenz curve of the given alternative. Next, we showed theoretical relationship between stochastic dominance and the coefficient of inequality as a means to determine the preferred alternative when decision is made with incomplete information about decision maker's utility function. Then, two experiments were performed to test subject‘s attitude toward risk. The results of the experiments support the idea that when a decision maker is risk averse or risk prone, he/she can use the coefficient of inequality as a decision rule to choose the preferred alternative instead of using stochastic dominance. Thus, according to decision maker’s attitude toward risk, the decision rule proposed here can be used as a valuable aid in decision making under uncertainty with incomplete information.

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Evaluation of Photosynthetic Ability in Two Representative Evergreen Broad-leaved Tree Species in Korea

  • Kim, Dong-Hak;Park, Yong Mok
    • Journal of Environmental Science International
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    • v.26 no.10
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    • pp.1147-1153
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    • 2017
  • To maintain a rich biological diversity is important to develop for biomaterial resources such as Korean evergreen broad-leaved tree species, the distribution of which is restricted to the southern part of Korean peninsula. We assessed photosynthetic characteristics of Quercus acuta and Castanopsis sieboldii, the representative evergreen broad-leaved trees in Korea, in order to establish a basis for conservation strategy related to distributional change in evergreen broad-leaved tree species according to climate change. Photosynthetic characteristics were evaluated in the sun and shade leaves of the two species. Sun leaves in both species revealed higher light compensation point and maximum photosynthetic rate compared to the shade leaves. In addition, photosynthetic rate was higher in Q. acuta than C. sieboldii, which was supported by a higher leaf nitrogen content and leaf mass per area. Water use efficiency was also higher in Q. acuta as compared to that in C. sieboldii. Similar photosynthetic rate, however, was shown in photosynthetic response to $CO_2$ concentration in the intercellular space. These results suggest that both species could respond differently to the changing environmental factors including climate change, suggesting the possibility of distributional changes resulting from a differential growth rate.

Genetic variation and relationship of Artemisia capillaris Thunb.(Compositae) by RAPD analysis

  • Kim, Jung-Hyun;Kim, Dong-Kap;Kim, Joo-Hwan
    • Korean Journal of Plant Resources
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    • v.22 no.3
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    • pp.242-247
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    • 2009
  • Randomly Amplified Polymorphic DNA (RAPD) was performed to define the genetic variation and relationships of Artemisia capillaris. Fifteen populations by the distributions and habitat were collected to conduct RAPD analysis. RAPD markers were observed mainly between 300bp and 1600bp. Total 72 scorable markers from 7 primers were applied to generate the genetic matrix, and 69 bands were polymorphic and only 3 bands were monomorphic. The genetic dissimilarity matrix by Nei's genetic distance (1972) and UPGMA phenogram were produced from the data matrix. Populations of Artemisia capillaris were clustered with high genetic affinities and cluster patterns were correlated with distributional patterns. Two big groups were clustered as southern area group and middle area group. The closest OTUs were GW2 and GG1 in middle area group, and GB1 from southern area group was clustered with OTUs in middle area group. RAPD data was useful to define the genetic variations and relationships of A. capillaris.