• Title/Summary/Keyword: marginal species

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First record of Lucicutia gaussae (Calanoida, Lucicutiidae) from Korean waters

  • Seok Ju Lee;Min Ho Seo;Ho Young Soh
    • Journal of Species Research
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    • v.13 no.2
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    • pp.178-184
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    • 2024
  • Two species (Lucicutia clausi, L. flavicornis) of Lucicutia (Lucicutiidae Sars, 1902) have been reported in Korean waters and one species(L. gaussae) is newly added the Tsushima Warm Current realm. Specimens from Korean waters are morphologically consistent with previous morphological characteristics of L. gaussae, but these differ in the following characteristics: 1) the male antennule with one process on segments XIX-XX, one process on segment XVIII, and three processes on segments XXI-XXIII; 2) in male leg 5, basis of left leg in the Korean specimen with small spine processes on the protrusion; 3) in male leg 5, the third exopodal segment of left leg without an inner marginal spine. In this study, we provide a redescription of L. gaussae insufficiently described by previous authors.

On Generating a Dynamic Price Formation System with Rationality -Application to U.S. Fisheries- (합리성을 가진 동태적 가격형성모형의 연구 -U.S. 수산자원에의 응용-)

  • Park, Hoanjae
    • Environmental and Resource Economics Review
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    • v.14 no.3
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    • pp.699-728
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    • 2005
  • This article is basically an extension of Barten(1993), Brown et al. (1995), Holt and Bishop's(2002) price formation system. A new dynamic price formation system is attempted considering full rationality of the consumers' side. The underlying idea of the new dynamic price formation system is that consumers are rational and farsighted and thus consider past and future consumptions in addition to current consumption to accept the prices traders called. In an empirical application, the U.S. commercial fish demand data are particularly interesting to this analysis in which the species are over fished, including many of the most valuable species. Especially, the grouper-snapper complex are under management jurisdiction of the National Marine Fisheries Council. In the empirical section, it shows how to adapt the model to estimate the marginal values to consumers of commercial fisheries. Since it is conceived of regulations as inducing movements along the marginal value curves, it is of growing importance to regional and national policy makers who are confronted with competing claims on diminishing fish stocks by commercial fisheries interests. It performs well and shows the plausible signs and magnitudes of price flexibilities and interaction among species. It further contributes to the general methodology of applied economics.

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Comparison of environmental characteristics at Cicuta virosa habitats, an endangered species in South Korea

  • Shin, Cha Jeong;Nam, Jong Min;Kim, Jae Geun
    • Journal of Ecology and Environment
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    • v.36 no.1
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    • pp.19-29
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    • 2013
  • Cicuta virosa is an endangered species in Korea, which is a southern marginal area. To conserve and restore habitats of this plant, we investigated water and soil environmental characteristics and vegetation at four habitats during the growing season. The C. virosa habitats differed in community structure, water and substrate properties, and water regime. Although the total distribution ranges of the water and soil environments for C. virosa were wide and overlapped with the optimal environmental range of distribution of accompanying species, the optimal water level range for C. virosa was defined as $7{\pm}3.5$ cm. Water level was adjusted by substrate structure such as a mound of P. japonica and a floating mat comprised of accompanying species. A floating mat was an aid to maintain an optimal and stable water level in deep or fluctuating water and to prevent strong competition with prolific macrophytes. The GS sampling site, which had floating mats, could be a good model for C. virosa conservation in a warm temperate region, whereas the PC sampling sites, which experienced a water shortage in spring, provided a clue about the decline in C. virosa population size.

New record of the red algae, Halarachnion parvum (Gigartinales) and Champia lubrica (Rhodymeniales), from Korea

  • Yang, Mi Yeon;Koh, Young Ho;Kim, Myung Sook
    • Journal of Ecology and Environment
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    • v.38 no.4
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    • pp.663-671
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    • 2015
  • We report the first finding of Halarachnion parvum and Champia lubrica from Korea based on morphology and the plastid rbcL sequence analyses. H. parvum occurs in the subtidal zone of Munseom, the southern part of Jeju. Thalli have short stipe, and elliptical to ovate fronds with marginal proliferations of up to 3 cm in height. H. parvum has zonately divided tetrasporangia and cystocarp immersed under the cortical layer. Champia lubrica appears in Namhae, Gyeongnam and Seopseom, Jeju. Thalli are erect, irregularly branched, terete, obtuse apex, up to 3-5 cm high, and have tetrahedrally divided tetrasporangia. Molecular analyses of the plastid rbcL gene reveal that two species are clearly separated from other species of their respective genera. H. parvum is sister with Halarachnion latissimum in 3.1-3.2% sequence divergence, and C. lubrica is closely related to the sample from Japan with 0.2% sequence divergence.

Two Newly Recorded Species of the Genus Aoroides (Crustacea: Amphipoda: Aoridae) from Korea

  • Jung, Tae Won;Kim, Jong Guk;Yoon, Seong Myeong
    • Animal Systematics, Evolution and Diversity
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    • v.32 no.2
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    • pp.72-85
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    • 2016
  • Two aorid amphipods, Aoroides ellipticus Ariyama, 2004 and A. semicurvatus Ariyama, 2004 from shallow waters of South Korea are reported here. Aoroides ellipticus has the characteristic setation of gnathopod 1 and the elliptical shape of basis on pereopod 7, while A. semicurvatus can be easily distinguished from congeners by combined characters of the curved propodus on gnathopod 2 and the absence of marginal spines on outer ramus of uropod 3 in mature males. This paper redescribed these two aorids and provided a key to Korean Aoroides species.

한국산 목본식물에 대한 계통분류학적 연구

  • Kim, Kyung Sik
    • Journal of Plant Biology
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    • v.27 no.1
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    • pp.15-24
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    • 1984
  • Leaf venation of 12 species of Lauraceae in Korea, native or introduced, was investigated and described by the use of Soft X-Ray. They could be grouped by the venation types, such as, 1. Actinodromous; Lindera obtusiloba, 2. Acrodromous; Cinnamomum camphora, C. japonicum, C. loureirii, 3. Brochidodromous having strongly developed basal secondary vein; Neolitsea aciculata, N. sericea, 4. Brochidodromous hoving irregulary branched secondary vein; Lindera erythrocarpa, L. glauca, 5. Brochidodromous having weak marginal loop; Machilus thunbergii, M.Japonica, 6. Brochidodromous having typical venation; Iozoste lancifolia, Litsea japonicum. This grouping corresponded with current classifying system at genus level except for genus Lindera, and supported Nakai's system at Tribe level. They also showed a gradual transition from brochidodromous to actinodromous types, but to certify the systematic value of this transition warrented more study. Identifying key for the species could be made by the venation type.

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Redescriptions of Euplotes encysticus and E. rariseta (Protist: Ciliophora: Euplotida)

  • Kim, Eun-Hee;Lee, Won Je
    • Journal of Species Research
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    • v.8 no.1
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    • pp.128-135
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    • 2019
  • Two euplotid ciliates, Euplotes encysticus Yonezawa, 1985 and E. rariseta Curds et al., 1974, were isolated from a freshwater pond called Mulgol in Dokdo of the East Sea and from Masan Bay/Jeju Island, Korea, respectively. Both species are redescribed based on live observations and protargol impregnation. Cells of Euplotes encysticus are asymmetrically oval, $63-79{\times}41-61{\mu}m$ in vivo and capable of encystment. The cells have 31-36 adoral zone of membranelles(AZM), 9 fronto-ventral cirri (FVC), 5 transverse cirri (TC), 2-3 caudal cirri (CC), 2 marginal cirri (MC), 7 dorsal kineties (DK), and 19-22 dorsal cilia in middle DK. The cells of Euplotes rariseta has a small ovoid form and are $32-44{\times}23-35{\mu}m$ in vivo, 18-22 AZM, 10 FVC, 5 TC, 2 CC, 1 MC and 6 DK.

New record of three hypotrich soil ciliates(Ciliophora: Hypotricha) from South Korea: Oxytricha multilineata, Mixophrya pantanalensis pantanalensis and Caudiurostyla sinensis

  • Kyu-Seok Chae;Gi-Sik Min
    • Journal of Species Research
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    • v.12 no.4
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    • pp.307-312
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    • 2023
  • Oxytricha multilineata, Mixophrya pantanalensis pantanalensis, and Caudiurostyla sinensis were isolated from soil samples collected from Cheongju-si and Yeoju-si, confirmed as new to South Korea. Oxytricha multilineata was distinguished from other congeners by seven dorsal kineties and dorsal bristles about 15 ㎛ long. Mixophrya pantanalensis pantanalensis was characterized by five to seven lithosomes and six dorsal kineties. Caudiurostyla sinensis was characterized by colorless cortical granules present, 10-14 midventral pairs, 7-9 left and 6-9 right marginal rows and four or five dorsal kineties. We determined the ribosomal DNA sequences (including 18S rDNA, ITS1, 5.8S rDNA, ITS2, and partial 28S rDNA) from above three species. And the genetic distances were compared with their congeners.

Carbon Forestry: Scope and Benefit in Bangladesh

  • Rahman, Md. Siddiqur;Akter, Salena
    • Journal of Forest and Environmental Science
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    • v.29 no.4
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    • pp.249-256
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    • 2013
  • The aim of the study was to reveal the scope and benefits derives from establishing carbon forests in a country like Bangladesh. Carbon forestry is the modernized forestry practice that evolves no cutting of trees or vegetation rather conserves them in the wood. Trees might be the source of carbon sink at large scale by establishing carbon forests. To find out how and in what extent forests of Bangladesh could contribute to global emission reduction, tree species of economic importance were taken into account about their carbon sequestration potential. Data source was a secondary one. Bangladesh has subtropical evergreen and deciduous forest tree species. Here trees can sequester almost 45-55 percent organic carbon in their biomass. On an average, trees in different types of stands can sequester 150-300 tC/ha. Carbon value of these forests might be 7,500-15,000 USD per hactre (assuming 50 USD per equivalent $tCO_2$). Thus, accounting tree carbon credits of total forested lands of Bangladesh, there might be a lump sum value of $1.89{\times}10^{10}-3.79{\times}10^{10}$ USD. If soil carbon is added, this amount would jump. Alternatively, there are two times higher spaces as marginal lands than this for starting carbon forestry. However, carbon forestry concept is still a theoretical conception unless otherwise their challenges are addressed and solved. Despite of this, forests of Bangladesh might be the key showcase for conserving biodiversity in association with carbon capture. Protected areas in Bangladesh are of government wealth, however, degraded and denuded waste and marginal lands might be the best fit for establishing carbon forests.

Animal Ethics and Argument from Marginal Cases (동물 윤리학과 '가장자리 경우 논증')

  • Moon, Sung-Hak
    • Journal of Korean Philosophical Society
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    • v.148
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    • pp.129-156
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    • 2018
  • Recently, a lot of articles and writings defending animal right and welfare are introduced into our society. For example, P. Singer's Animal Liberation, T. Regan's The Case for Animal Rights, and J. Rachels's Created From Animal are representative writings of animal ethics. In his books, P. Singer maintains that all animals are equal. T. Regan insisted that animals as a subject of a life have rights. J. Rachels's moral individualism is that how an individual may be treated is to be determined, not by considering his group membership, but by considering his own particular characteristics. Interestingly, they use common argument called 'argument from marginal cases' to justify their theoretical positions. If we can disclose the weakness of the argument, all kinds of animal ethics which defend animal right and welfare such as animal liberation theory, animal rights theory and moral individualism will collapse. In this paper, I will examine the concrete contexts in which Singer, Regan and Rachels make use of the argument. And I will critically examine the argument. Lastly I will show that the attempt to deny the difference of species is unsuccessful.