• Animal Systematics, Evolution and Diversity
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• v.38 no.4
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• pp.205-213
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• 2022

A new free-living marine nematode, Chaetonema longicorpus sp. nov., was discovered in a subtidal benthic habitat around the Uljin nuclear power plant in the East Sea. Chaetonema longicorpus sp. nov. differs from other Chaetonema species in its very long body length, relatively long cephalic setae, long and narrow buccal cavity, bottle-shaped amphideal fovea, short spicules, only one pre-cloacal seta instead of a pre-cloacal supplement, and conspicuous ventral swelling at the middle of the tail. Herein, we provide a taxonomic description and illustrations of this new species using differential interference contrast microscopy. Furthermore, an illustrated pictorial key to all valid species, including the new species and comparative tables on the biogeographical and morphological characteristics of the genus Chaetonema, are provided.

• Korean Journal of Environment and Ecology
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• v.27 no.3
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• pp.357-368
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• 2013

This study was carried out to classify and describe the vegetation of algific talus in Korea by methods of the ZM school of Phytosociology. A part of slope or a hollow at the foot of talus in which cool air exhausts from underground through gaps of accumulated rock debris is called algific talus. From the sixty three stands obtained, the following two community and their four subcommunity were recognized: A. Quercus variabilis - Cystopteris fragilis com. B. Quercus mongolica - Betula schmidtii com. B-1. Quercus serrata - Urtica angustifolia subcom. B-2. Sorbus commixta - Spiraea chamaedryfolia subcom. B-3. Zabelia biflora - Astilboides tabularis subcom. B-4. Typical subcom. A. Quercus variabilis - Cystopteris fragilis com.. As a result of DCCA ordination, Quercus variabilis - Cystopteris fragilis com. has Quercus variabilis, Ligustrum var. obtusifolium, Zelkova serrata, Viburnum carlesii etc. as differential species, which showed the higher correlation with area of high Warmth index (WI) and precipitation than Quercus mongolica - Betula schmidtii com. has Quercus mongolica, Sorbaria var. sorbifolia, Magnolia sieboldii, Acer pseudosieboldianum, Rosa acicularis etc. as differential species. Sorbus commixta - Spiraea chamaedryfolia subcom. has Spiraea chamaedryfolia, Sorbus commixta, Rosa koreana, Vaccinium var. hirtum, Acer tegmentosum, Dryopteris expansa, Abies holophylla etc. as differential species. and Typical subcom in Quercus mongolica - Betula schmidtii com. were distributed in higher altitude and precipitation area than others. Zabelia biflora - Astilboides tabularis subcom. has Spiraea chinensis, Zabelia biflora, Astilboides tabularis, Gymnocarpium jessoense, Saussurea mongolica, Larix kaempferi etc. as differential species, which was distributed in area with high amounts of sunlight exposure by human activities.

• The Korea Journal of Herbology
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• v.29 no.6
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• pp.133-140
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• 2014

Objectives : Paemo is a phlegm-resolving drug with cold properties and classified 5 kinds which come from 11 species of original plant. All the more, according to literature record, 20 species of original plant were used. As a natural result, these are easily to confuse and there are a lot of counterfeit product. So we are to present a differential standard of Paemo. Methods : It was planed a differential standard form through outer appearance of the original plant and outer appearance in the form of each medicines which was collected local market or field for 11 species which is listed in Korea or China pharmacopeia. Results : It was possible to distinguish the orignal plant between Fritillaria and Bolbostemma through its stem shape. In Fritillaria of original plant, it was possible to distinguish through its width of leaf, number of leafy bracts, color and position of flower and shape of leaf apex. In outer appearance in the form of each medicines, there are difference in color and texture of medicine between Fritillaria and Bolbostemma and there are difference in size, shape, size of inner and outter fleshy leaf of bulb, pattern of surface and apex of fleshy leaf of bulb among 10 Fritillaria species. Conclusions : This study presents various differences in the outer appearance of the original plant and the outer appearance in the form of each medicines among Paemo. It will be helpful to further applied research.

• Journal of Plant Biology
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• v.34 no.4
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• pp.341-347
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• 1991

The character and differential species of Abies koreana community, a subalpine coniferous forest, on Mt. Hall a and its vegetation unit were reviewed, based on literature published up to date. Song and Nakanish (1985a) originally described Saso-Abietetum koreanae Song et Nakanishi 1985 for the community. At that time, we were fully justified in establishing the nomenclature. Nevertheless, against this nomenclature, Yim and Kim (1990) made a objection, and it was renamed as what is called Saso quelpaertensi-Abietetum koreanae (Song et Nakanishi) corr. Yim et Kim 1990. In their previous study(Yim et al., 1990) being the root of the nomenclature, however, they did not study on the full layers containing the moss layer of bryophyte and lichen for the stratification of the Abies koreana community, in spite of the importance of the species of moss layer for the selection of character and differential species of vegetation units belonging to Vaccinio-Piceetea Br.-Bl. 1939, and also the floristic composition from their study was not compared with that of the vegetation units of the subalpine coniferous forests in Korea Peninsula, Japan, Maritime Province of Siberia and Northeast China. Among the four character species selected by them, it is clear that Maianthemum bifolim and Lonicera maackii are species no having the characteristic value from the phytosociological viewpoint. Besides, Sasa quelpaerthensis described in their nomenclature is a synonym of S. palmata (Suzuki, 1978). Therefore, their nomenclature is invalid and comes under a contravention (Infringement of Priority) to the Code of Phytosociological Nomenclature (Barkman et al., 1986). Saso-Abietetum koreanae was amply justified also by author's recent study (Song, 1991)examined throughout the range of subalpine coniferous forest in Korea. With the discussion of justification of Saso-Abietetum koreanae, a association discussion was brought in the present review.

• Korean Journal of Environment and Ecology
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• v.29 no.5
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• pp.791-802
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• 2015

The study was carried out to analyze vegetation structure of Mt. Eungbok located in Jochimryeong to Shinbaeryeong of the Baekdudaegan mountain range. The survey for 25 plots was conducted from April 2012 to August 2013 in the permanent plots using phytosociological analysis. As a result, the vegetations were classified into four vegetation units. In species composition, they were classified into Quercus mongolica community group divided into 2 community such as Ulmus laciniata community and Corylus sieboldiana var. mandshurica community, U. laciniata community was subdivided Rhododendron schlippenbachii group and Rubus crataegifolius group(into Viola albida subgroup, Rubus oldhamii subgroup). In terms of Importance values according to layer-specific and altitude of ridge, Q. mongolica was the highest importance value of tree layer and Acer pseudosieboldianum was highest importance value of sub tree layer. Therefore Q. mongolica and A. pseudosieboldianum could likely remain in the future of tree layer and sub tree layer respectively. Analysis of dominance most value of vegetation are on about 0.3. In ridge area was a species diversity result, vegetation unit 3 showed the highest value 0.974 and vegetation unit 1 showed the lowest value 0.725. Based on the interspecific association showed four types which were coincident with differential species and character species on the constancy table. Specially type I plant species were mostly differential species and the characteristic species, which appeared in the Rhododendron schlippenbachii community classified phytosociologically, and type III plant species were mostly the species appearing in the Corylus sieboldiana var. mandshurica community growing in the relatively.

• Kyungpook Mathematical Journal
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• v.48 no.3
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• pp.515-527
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• 2008

We investigate a three species food chain system with a Holling type IV functional response and impulsive perturbations. We find conditions for local and global stabilities of prey(or predator) free periodic solutions by applying the Floquet theory and the comparison theorems.

• Journal of applied mathematics & informatics
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• v.27 no.5_6
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• pp.1097-1107
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• 2009

In this paper, three species stage-structured predator-prey model with time delayed and periodic constant impulsive perturbations of predator at fixed times is proposed and investigated. We show that the conditions for the global attractivity of prey(pest)-extinction periodic solution and permanence of the system. Our model exhibits a new modelling method which is applied to investigate impulsive delay differential equations. Our results give some reasonable suggestions for pest management.

• ALGAE
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• v.25 no.3
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• pp.121-131
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• 2010

Thalassiosira species were collected from October 2007 to January 2009 in an attempt to better understand species diversity of the genus Thalassiosira in Korean coastal waters. A total of 5 Thalassiosira species (T. concaviuscula, T. oceanica, T. partheneia, T. simonsenii and T. nanolineata) were identified here. Most species in this study were of small size, and 5 species were recorded for the first time in Korean coastal waters. Using a scanning electron microscope (SEM), we described distinctive characteristics of fine structure that proved to be important diagnostic characteristics for the identification of each species. The most important diagnostic characteristics for Thalassiosira species identification were the marginal strutted processes, the position of labiate processes, and the areolation. The differential characteristics of the species studied were: T. concaviuscula has a double layered external tubes on the marginal strutted processes; T. oceanica shows marginal ridges that are interlinked between the marginal strutted processes; the valve face of T. partheneia is fairly convex and its labiate process is positioned midway between two strutted processes; T. simonsenii is characterized by two labiate processes and somewhat coarse areolae; and, T. nanolineata has several central strutted processes and linear areolation.

• Kyungpook Mathematical Journal
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• v.48 no.3
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• pp.503-514
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• 2008

We investigate a three-species food chain system with Lotka-Volterra functional response and impulsive perturbations. In [23], Zhang and Chen have studied the system. They have given conditions for extinction of lowest-level prey and top predator and considered the local stability of lower-level prey and top predator eradication periodic solution. However, they did not give a condition for permanence, which is one of important facts in population dynamics. In this paper, we establish the condition for permanence of the three-species food chain system with impulsive perturbations. In addition, we give some numerical examples.

• Korean Journal of Environmental Biology
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• v.37 no.3
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• pp.396-405
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• 2019

A new species of free-living marine nematode is described from intertidal sediments of the East Sea, Korea. Phanoderma koreense sp. nov. is characterized by the presence of well-developed pharyngeal and cephalic capsule, six inner labial sensilla present as minute papillae around with circular groove, long and slender spicules with 4-5 serrated distal end, located at the base of the precloacal supplement, a series of eight to nine stout and short setae on the ventral cloacal region and conico-cylindrical tail with two pairs of blunt setae. In this study, we provide taxonomic descriptions and illustrations of a new species by differential interference contrast microscope and a pictorial key to the valid species of Phanoderma Bastian, 1865. This is the first record of the genus Phanoderma in the East Sea, Korea.