• Title/Summary/Keyword: the distributional ratio

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Environmental Equity Analysis of the Accessibility of Urban Neighborhood Parks in Daegu City (대구시 도시근린공원의 접근성에 따른 환경적 형평성 분석)

  • Seo, Hyun-Jin;Jun, Byong-Woon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.14 no.4
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    • pp.221-237
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    • 2011
  • This study aims to investigate the environmental equity of the accessibility to urban neighborhood parks in the city of Daegu. The spatial distribution of urban neighborhood parks was explored by spatial statistics and the spatial accessibility to them was then evaluated by both minimum distance and coverage approaches. Descriptive and inferential statistics such as proximity ratio, Mann Whitney U test, and logistic regression were used for comparing the socioeconomic characteristics over different accessibilities to the neighborhood parks and then testing the distributional inequity hypothesis. The results from the minimum distance method indicated that Dalseo-gu had the best accessibility to the neighborhood parks while Dong-gu had the worst accessibility. It was apparent with the coverage method that Dalseo-gu had the best accessibility whereas Dong-gu and Nam-gu had the worst accessibility to the neighborhood parks at 500m and 1,000m buffer distances. There existed the spatial pattern of environmental inequity in old towns with respect to population density and the percentage of people under the age of 18. The spatial pattern of environmental inequity in new towns was explored on the basis of the percentage of people over the age of 65, the percentage of people below the poverty level, and the percentage of free of charge rental housing. These results were closely related to the development process of urban parks in Daegu stimulated by the quantitative urban park policy, urban development process, and residential location pattern such as permanent rental housing and free of charge rental housing. This study further extends the existing research topics of environmental justice related to the distributional inequity of environmental disamenities and hazards by focusing on environmental amenities such as urban neighborhood parks. The results from this study can be used in making the decisions for urban park management and setting up urban park policy with considering the social geography of Daegu.

Distributional Characteristics of Benthic Macroinvertebrates and Freshwater Fish in Seonun Stream, South Korea (선운천 일대의 저서성 대형무척추동물 및 어류분포 특성)

  • Jung, Sang-Woo;Han, Jeong-Ho;Bae, Yeon-Jae;Paek, Woon-Kee
    • Korean Journal of Environment and Ecology
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    • v.30 no.3
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    • pp.353-368
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    • 2016
  • This study surveyed the diversity and distributional characteristics of benthic macroinvertebrates and freshwater fish during the period from April to October, 2015 in Seonun Mountain Provincial Park. As a result, a total of 78 species of benthic macroinvertebrates belonging to 50 families, 16 orders, and four phyla were observed in Seonun stream; additionally, 25 species of freshwater fish belonging to six families were identified in all the investigated sites. Among benthic macroinvertebrates, Ephemeroptera(13 spp.: 22.81%) was the largest group in terms of species richness. In the FFGs, gathering-collectors(30 spp.: 36.14%) were relatively larger as represented by Ephemeroptera that usually inhabit fast flowing streams. In the HOGs, clingers(23 spp.: 29.49%) and burrowers(17 spp.: 21.79%) were the dominant groups. For both EPT ratio and ESB index, site 8 appeared to be the highest with 44.44% and 72 marks respectively, while the sites 4 and 9 showed relatively lower rates and indices. According to the results of evaluation, site 8 needs to be designated as the highest protection area while the sites 4 and 9 may be designated as target areas for preferential improvement. According to the analysis of fish community, the dominant species was Zacco teminchkii(333 inds.: 36.80%), and the dominant index was the lowest(0.24) and diversity index was the highest(1.81) at site 8, which therefore represents a stable freshwater fish community. In this survey, six Korean endemic species were identified: Ephemera separigata, Neoperla coreensis, Rhodeus uyekii, Squalidus gracilis majimae, Microphysogobio yaluensis, and Iksookimia koreensis. Also, three species belonging to the management of exportable group(Davidius lunatus, E. separigara, N. coreenis) were observed. Two habitat specific species: Thraulus grandis and Anguilla marmorata, were found for the first time in Gochang area and marked on the Korean distribution map through discussion.

Distributional characteristics of phytoplankton and nutrient limitation during spring season in Jinhae Bay (춘계 진해만에서 식물플랑크톤 증식과 제한영양염 분포특성)

  • Son, Moonho;Kim, Dongseon;Baek, Seung Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.5
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    • pp.3345-3350
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    • 2014
  • We investigated to assess the relationships between the major nutrients and phytoplankton dynamics during the spring season in 2010 and 2011 at 23 stations in Jinhae Bay, Korea. The bay is divided into four different zones based on pollutant sources and geographical characteristics. Nutrient limitation (>80%) was significant in Zone II, which is located in central bay and is influenced by the water well mixed from outer bay. The limited nutrient was followed in Zone III and IV that was occupying between 17% and 83%. However, the low levels are being kept below 35% in Zone I, which is characterized by the semi-enclosed eutrophic area of Masan and Haegam bays. Based on the PCA (principle component analysis) analysis, the nitrogen (N) sources in 2010 were particularly dominant and it may be due to the water mixing and wastewater formed from bottom layers and sewage. In 2011, major nutrients including nitrogen, silicon and phosphorus were dominant in the bay and are supplied by the river discharge after rainfalls with low salinity conditions. In particular, the N nutrients being supplied in 2010 are correlated with pennate diatoms Pseudo-nitzchia spp. and is not related to the phytoplankton population densities in 2011. The present study suggests that N sources play an important role in the proliferation of diatom, and the rapid nutrient uptakes by them are potential nutrient limitation factors in the bay.

Ecological Characteristics of Dorcus hopei(E Saunders) for the Development of Mass-rearing Technique in Korea (왕사슴벌레(Dorcus hopei)의 대량사육 기술개발을 위한 생태특성 조사)

  • Kim, Chul-Hak;Lee, Jun-Seok;Jung, Geun;Park, Kyu-Taek
    • Korean journal of applied entomology
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    • v.43 no.2
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    • pp.135-141
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    • 2004
  • This study was carried out to review the distributional data of Dorcus hopei in Korea and to investigate ecological characteristics to develop a mass rearing technique of the species. The coupling period of the male and female was needed at least 2 weeks in condition of 6 months after emergence, and the optimal sex ratio for oviposition was 2♀:1♂. Eggs were laid singly, up to 27.3 per female. The pre-ovipostion period was average 147.3 days, egg-period was 15.6 days on the average, and oviposition period was at least 120 days. The optimum size of oviposition room was 55${\times}$40${\times}$35 cm with 3-4 oviposition-trees cut in size of 15${\times}$15 cm. Quercus acutissima was highly preferred for the oviposition. Developing period of each instar in the insectary (25$^{\circ}C$, 75% R.H.. 16L:8D) was 24.1 days for the 1st instar,29.8 days for the 2nd, and 131.2 days for the 3rd instar, and 28.9 days for the pupa. The longevity of adults was longer than 35 months. The period of induced dormancy was needed at least 3-4 months.

The Distribution and Management Methods of Naturalized Plants in Jeollanamdo, Korea - A Focus on the South-Western Area - (전남지역 귀화식물 분포 및 관리방안 - 서남권을 중심으로 -)

  • Lim, Dong-Ok;Park, Moon-Su;Kim, Ha-Song
    • Korean Journal of Plant Resources
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    • v.20 no.4
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    • pp.353-361
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    • 2007
  • This study was conducted to investigate the distribution of naturalized plants in Jeollanamdo which is located in the south-western areas of Korea from May 10, 2005 to December 20, 2006, and to suggeste the management methods of naturalized plants. The naturalized plants constisted of 29 families, 84 genera, 122 species, 8 varieties, totaling 130 taxa and ratio of naturalization was 45 percents at the study sites. According to the number of species investigated from each sites, 103 taxa were from Yeongam, 98 taxa were from Mokpo, 97 taxa were from Shinan, while it was higher in the other sites. A total of 30 naturalized plant communities were classified. In those eight sites, the common appearance communities were Robinia pseudo-acacia, Amorpha fruticosa, Bromus catharticus, Eragrostis curvula, Festuca arundinacea, Festuca myuros, Lolium multiflorum, Lolium perenne, Paspalum distichum var. indutum, Rumex obtusifolius, Oenothera biennis, Lepidium apetalum, Trifolium repens, Ambrosia artemisiofolia var. elatior, Comos bipinnatus, Rudbeckia bicolor, Erigeron annuus, Erigeron annuus-Erigeron canadensis, Coreopsis lanceolata, Cosmos sulphureus community. The distributional characteristics of naturalized plants were divided on the basis of six areas associated with ecological characteristics of a habitat

Technical Efficiency in Korea: Interindustry Determinants and Dynamic Stability (기술적(技術的) 효율성(效率性)의 결정요인(決定要因)과 동태적(動態的) 변화(變化))

  • Yoo, Seong-min
    • KDI Journal of Economic Policy
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    • v.12 no.4
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    • pp.21-46
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    • 1990
  • This paper, a sequel to Yoo and Lee (1990), attempts to investigate the interindustry determinants of technical efficiency in Korea's manufacturing industries, and also to conduct an exploratory analysis on the stability of technical efficiency over time. The hypotheses set forth in this paper are most found in the existing literature on technical efficiency. They are, however, revised and shed a new light upon, whenever possible, to accommodate any Korea-specific conditions. The set of regressors used in the cross-sectional analysis are chosen and the hypotheses are posed in such a way that our result can be made comparable to those of similar studies conducted for the U.S. and Japan by Caves and Barton (1990) and Uekusa and Torii (1987), respectively. It is interesting to observe a certain degree of similarity as well as differentiation between the cross-section evidence on Korea's manufacturing industries and that on the U.S. and Japanese industries. As for the similarities, we can find positive and significant effects on technical efficiency of relative size of production and the extent of specialization in production, and negative and significant effect of the variations in capital-labor ratio within industries. The curvature influence of concentration ratio on technical efficiency is also confirmed in the Korean case. There are differences, too. We cannot find any significant effects of capital vintage, R&D and foreign competition on technical efficiency, all of which were shown to be robust determinants of technical efficiency in the U.S. case. We note, however, that the variables measuring capital vintage effect, R&D and the degree of foreign competition in Korean markets are suspected to suffer from serious measurement errors incurred in data collection and/or conversion of industrial classification system into the KSIC (Korea Standard Industrial Classification) system. Thus, we are reluctant to accept the findings on the effects of these variables as definitive conclusions on Korea's industrial organization. Another finding that interests us is that the cross-industry evidence becomes consistently strong when we use the efficiency estimates based on gross output instead of value added, which provides us with an ex post empirical criterion to choose an output measure between the two in estimating the production frontier. We also conduct exploratory analyses on the stability of the estimates of technical efficiency in Korea's manufacturing industries. Though the method of testing stability employed in this paper is never a complete one, we cannot find strong evidence that our efficiency estimates are stable over time. The outcome is both surprising and disappointing. We can also show that the instability of technical efficiency over time is partly explained by the way we constructed our measures of technical efficiency. To the extent that our efficiency estimates depend on the shape of the empirical distribution of plants in the input-output space, any movements of the production frontier over time are not reflected in the estimates, and possibilities exist of associating a higher level of technical efficiency with a downward movement of the production frontier over time, and so on. Thus, we find that efficiency measures that take into account not only the distributional changes, but also the shifts of the production frontier over time, increase the extent of stability, and are more appropriate for use in a dynamic context. The remaining portion of the instability of technical efficiency over time is not explained satisfactorily in this paper, and future research should address this question.

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GIS-based Areal Distribution Ratios and Characteristics of Constituent Rocks with Geologic Ages and Rock Types in Jeonnam and Gwangju Areas (전남과 광주지역 구성암류의 GIS에 의한 지질시대별 암층별 분포율 및 분포특성)

  • Yun, Hyun-Soo;Lee, Jin-Young;Hong, Sei-Sun;Yang, Dong-Yoon;Kim, Ju-Yong;Cho, Deung-Lyong
    • The Journal of the Petrological Society of Korea
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    • v.22 no.2
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    • pp.153-177
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    • 2013
  • To get the various data on geological information, distributional ratios and characteristics of constituent rocks with geologic ages and rock types were obtained by ArcGIS 10.1 program, digital geologic and geomorphic maps of 1:250,000 scale in Jeonnam and Gwangju areas. In the Jeonnam area, geologic ages can be largely divided into 7, in which their distribution ratios show decreasing trends in the order of Cretaceous, Precambrian, Jurassic, Quaternary, Age-unknown, Carbonifeorus-Triassic and Triassic, and the former fours make the most prevailing ratios of 94.80%. Rock types in the area can be assorted into 57 ones, in which major 7 ones occupy the dominant ratio of 71.68%. Among them, Kav (acidic volcanics+rhyolite and rhyolitic tuff) show much more distribution ratios than the others. It shows more aspects distributed in north, west, middle, east and south parts, especially in Sinan-Mogpo-Yeongam of west and Haenam of south parts in the area, respectively. On the other hand, geological ages in Gwangju area can be largely divided into 5, in which their distribution ratios show decreasing trends in the order of Jurassic, Quaternary, Cretaceous, Precambrian and Age-unknown, and the former fours occupy almost the whole ratio of 98.95%. Rock types in the area are 12 ones, in which major four ones make up the dominant value of 91.30%. Among them, Jurassic granites of the most dominant value are mostly occupied in the southwest-northeast part of the area. Next dominative Quaternary alluvium is mostly developed along the Yeongsan river, the Hwangryong river and their channel junction. And Yongdu and Donggye plains are well developed around the Yeongsan riverline, and channel junction of the Yeongsan and Hwangryong rivers in the area, respectively.

Rate of Sediment Accumulation and Geochemical Characteristics of Muddy Sediment in the Central Yellow Sea (황해 중앙부 해역 니질 퇴적물의 지화학적 특성 및 퇴적률)

  • 윤정수;김여상
    • The Korean Journal of Quaternary Research
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    • v.16 no.1
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    • pp.1-16
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    • 2002
  • A total of 4 muddy sediment samples collected from the Central Yellow Sea were analyzed for chemical composition. The results are compared with the previously published Huanghe, Changjiang and Keum River geochemical data in order to understand provenance and sedimentation of fine-grained mud, and the sediment accumulation rates estimated. The sandy sediment facies is distributed in the eastern area, a patch of fine-grained mud exists in the western central prat, and the sandy mud and clay sedimentary facies shot. north to south zonal distribution in the central region. The content of calcium carbonate ranges from 2.8 to 10.5%, and its distributional trends to be more concentrated on the western muddy sediments near toward the China side rather than on the eastern sandy sediments. The accumulation rates obtained using Pb-210 geochronologies for the muddy sediments in the Central Yellow Sea showed ranges from 0.21 to 0.68 cm/yr or 0.176 to 0.714 g/$\textrm{cm}^2$. yr. The sedimentation rate from core CY96010 located in the eastern near side of Shandong Peninsula which is affected by the Huanghe River shows 0.68 cm/yr or 0.714 g/$\textrm{cm}^2$ . yr. The sediment cores CY96008 and CY96002 in the Central Yellow Sea, the estimated of sediment accumulation rates shows 0.21~0.23cm1yr or 0.176~0.220 9/$\textrm{cm}^2$.Vr respectively, which are much lower than above samples. These indicate that the muddy sediments in central area of the Yellow Sea may have received influence of the sediment discharge from the Huanghe River. The concentrations of Ca, Na, Sr, Ho, La, Tb, Ta and Ca/Ti ratio of the muddy sediments in the Central Yellow Sea are higher than those of the Changjiang sediments and lower than those of the Huanghe sediments. However, these element values showed similar concentration patterns than those of the Huanghe sediment. The element contents such as Fe, Ti, Nl, Co, Cr, Cu, Pb, Sc, Ce, Nd, Sm, Eu, Cd and Dy in the study area are higher than those of the Huanghe sediments and lower than the Changjiang River sediments, but these values showed close to resemblance content trends those of the Changjiang sediment. The concentration of Mn, K and Sr in sediments of the study area are similar to those of the Keum River and eastern Yellow Sea sediment. They are rich in Zn, Rb, Cd, U, Cs and Li than those of the other comparison legions. Therefore, the terrigenous materials sources of the muddy sediment in the Central Yellow Sea comes mainly from Huanghe River in the past and present, and also have party derived from the Changjiang and Keum River, while the biological deposit in this area are carried by the Yellow Sea Warm Current.

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Distributional Characteristics, Population Structures and Fruition Dynamics of Korean Endemic plant, Prunus choreiana H. T. Im (한국특산 복사앵도나무(Prunus choreiana H. T. Im)의 분포특성, 개체군구조 및 결실동태)

  • Kim, Young-Chul;Chae, Hyun-Hee;Son, Sung-Won
    • Korean Journal of Environment and Ecology
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    • v.36 no.2
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    • pp.177-201
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    • 2022
  • Following the adoption of the global plant conservation strategies at the Conference of the Parties for Biodiversity Conservation, diligent actions to achieve each targets are actively carried out. In particular, the need for ecological conservation research to achieve targets 2 and 7 of GSPC-2020 has increased. The priority taxa to accomplish the objectives of GSPC-2020 are rare and endemic plants. In particular, endemic plants with limited distribution in specific regions are evaluated to face a high risk of extinction. To address the necessity to preserve endemic plants, we investigated the distribution of Prunus choreiana H. T. Im, a Korean endemic plant. After that, we examined the vegetational environment of the habitat of P. choreiana and evaluated its population structure. The productivity of its fruits and the effects of pollinators on fruit production were evaluated as well. The fruiting ratio was calculated based on the number of flowers produced. Lastly, we observed the annual growth characteristics of P. choreiana. The habitats of P. choreiana did not show a specific type of vegetation. All of them were located in a limestone area of Gangwon-do in the central Korean Peninsula and occupied a site where the coverage of the tree layer and the sub-tree layer was not high or did not exist. The population structure of P. choreiana contained a high proportion of mature plants capable of producing fruits and a low proportion of seedlings and Juvenile plants. We found that the production of fruits required pollinators and was affected by the performance of each plant. Although P. choreiana produces many flowers, only a maximum of 20% and only 2-6% on average bear fruits. These flowering characteristics may be due to pollinators' low abundance and activity during the flowering season (between mid-March and early April), suggesting that many flowers are needed to attract more pollinators. We rarely observed the re-establishment of seedlings in the population of P. choreiana. Despite that, we predict the population to persist owing to its long lifespan and periodic production of numerous fruits. However, if the tree layer and sub-tree layer in competing status with P. choreiana increase their crown density, they are expected to inhibit the growth of P. choreiana and affect the risk of its extinction. Therefore, the current changes in the vegetational environment of the habitats are expected to decrease the number and extent of P. choreiana in the long term. The results of this study may serve as primary and important data necessary for the achievement of GSPC-2020 objectives.

Parent Materials and Pedogenic Properties of the "Yongil" Series Distributed in Eastern Coastal Area of Korea (한국 동남해안지대에 분포된 영일통의 모재와 생성학적 특성)

  • Yun, Eul-Soo;Jung, Yeun-Tae;Son, Il-Soo;Jung, Ki-Yuol;Lee, Dong-Chang
    • Korean Journal of Soil Science and Fertilizer
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    • v.35 no.3
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    • pp.137-144
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    • 2002
  • To obtain the basic information about pedo-genetic properties and origin of the parent materials of "Yongil" series in Korea, this study was conducted. The soil characteristics such as chemical and sand particles of typifying pedon, and distributional patterns in the area were analysed. The typifying pedon of "Yongil" series was distributed on the top of rolling area in the eastern coastal area of Korea, Yonggan-ri, Heunghae-eup, Pohang-si, Gyongbuk province. The results are as follows; The "Yongil" series in Korea was distributed on the rolling hill under altituede of 50m, and was used for cultivated upland, and the total acreage about 376ha. The content of sand was more than 50%, however the clay content in the depth of 40~100cm of the soil profile rapidly increased. The medium sand (0.5~0.1mm in size) are dominant among sand fraction, but coarse one are rare. So the rate of medium to total sand was higher in IIB horizon as 0.62~0.76 than A and C horizons. The content of heavy minerals in medium sand was low as 1.0~6.6% and the ratio of quartz to feldspars was higher in Ap2 and B1 horizon as 1.7 than IIB horizon which had less than 1.39. The cumulative curves of sand particles in Yeongil series showed the well sorted and differ from residuum soils derived from sand stone, but similar to dune soils(Haeri series). So it could be deducted from this study that "Yeongil" series are aeolian deposits derived from aeolian materials and have bisequum profile; the upper part depth of 40cm was recent cover sand, the horizon of 40~100cm depth was developed in Pleistocene epoch from the same materials.