• Journal of Species Research
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• v.1 no.1
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• pp.4-34
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• 2012

Parastenocaris koreana sp. nov. is described based on examination of numerous adult specimens of both sexes from several localities in Korea. Scanning electron micrographs are used to examine intra- and interpopulation variability of micro-characters, in addition to light microscopy. The new species is most closely related to the Japanese P. biwae Miura, 1969, which we redescribe based on newly collected material from the Lake Biwa drainage area. The two species differ in size, relative length of the caudal rami, shape of the anal operculum, shape of the genital double somite, relative length of the inner distal process on the female fifth leg, as well as relative length of the apical setae on the second, third, and fourth legs exopods in both sexes. Detailed examinations of three disjunct populations of P. koreana reveal also some geographical variation, especially in the surface ornamentation of somites, which may indicate some population structuring or even cryptic speciation. Lack of intraspecific variability in the number and position of sensilla on somites, as well as their potential phylogenetic significance, is a novel discovery. Both species examined here belong to the brevipes group, which we redefine to include 20 species from India (including Sri Lanka), Australia, East Asia, Northern Europe, and North America. A key to species of this group is also provided. In order to test the monophyly of the redefined brevipes group with highly disjunct distribution, as well as relationship between different species, a cladistics analysis is performed based on 39 morphological characters and with help of three outgroup taxa. Six equally parsimonious cladograms are generated, all of which show that the ingroup is well defined by at least three synapomorphies. Reconstructed phylogeny questions the previously suggested hypothesis about the origin of this group in South East Asia, with one Australian species showing the most basal position. We speculate that the present distribution of this group may be a combination of ancient vicariance and subsequent dispersal, with a possible origin in the Gondwanaland, in the rift valley between Australia and India.

• Journal of Ecology and Environment
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• v.31 no.4
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• pp.297-307
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• 2008

In order to assess the effect of grazing on grasslands using floristic composition, we studied the floristic composition and plant biomass of steppe vegetation in Hulunbeier, Inner Mongolia. The dominant species of the grasslands were Stipa krylovii, Stipa grandis and Leymus chinensis. Floristic composition changed according to grazing pressure, being light, heavy and moderate. Under heavy grazing conditions, the importance value of P. acaulis, C. korshinskyi and Cleistogenes squarrosa increased in the plant community. These species were indicators of heavily grazed stand. Plant biomass of the stands ranged within 11.6g $m^{-2}$ and 63.5g $m^{-2}$ and 69.5g $m^{-2}$ and 166.2g $m^{-2}$ to the west and east of Lake Hulun, respectively. These values are equivalent to ca. $450{\sim}1,000kg$ of atmospheric carbon per hector, which is retained within the stand during the summer season.

• Journal of Species Research
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• v.2 no.2
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• pp.145-158
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• 2013

Candoninae is the most diverse group of freshwater ostracods with over 300 living species described from all around the world. However, only 11 species have been reported from South Korea. Considering abundant freshwater ecosystems here this number is very low. It is no wonder that newly collected samples of freshwater meiofauna often contain Candoninae ostracods which are new records for South Korea, or new taxa. Earicandona mounchyon gen. nov. sp. nov. and Typhlocypris (Pseudocandona) pratensis (Hartwig, 1901) were collected from two open freshwater bodies in Gangwon-do, and Gyeongsangbuk-do in South Korea. The new genus is most closely related to the breuili-group of Fabaeformiscandona Krstic, 1972. The most important apomorphic character of the new genus is a hemipenis with a poorly sclerified lobe "g", and prehensile palps with more rounded dorsal margins. Beside the new species, Earicandona contains only E. okuboi (Smith & Janz, 2008) comb. nov. from Lake Biwa. This species was originally described in Fabaeformiscandona, fabaeformis-group. They differ mostly in the morphology of the shell, but also some details of soft body, including the more pronounced genital process in the Korean species. Typhlocypris pratensis was so far known from Europe and this finding significantly broadens its area of distribution. Both Typhlocypris and Earicandona belong to the tribe Candonini and the key to the genera of this tribe is also presented here.

• Economic and Environmental Geology
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• v.56 no.6
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• pp.781-797
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• 2023

Recently, there has been a rapid response from mineral-demanding countries for securing critical minerals in a high tech industries. Graphite, while overwhelmingly dominated by China in production, is changing in global supply due to the exponential growth in EV battery sector, with active exploration in East Africa. Rare earth elements are essential raw materials widely used in advanced industries. Globally, there are ongoing developments in the production of REEs from three main deposit types: carbonatite, laterite, and ion-adsorption clay types. While China's production has decreased somewhat, it still maintains overwhelming dominance in this sector. Recent changes over the past few years include the rapid emergence of Myanmar and increased production in Vietnam. Nickel has been used in various chemical and metal industries for a long time, but recently, its significance in the market has been increasing, particularly in the battery sector. Worldwide, nickel deposits can be broadly classified into two types: laterite-type, which are derived from ultramafic rocks, and ultramafic hosted sulfide-type. It is predicted that the development of sulfide-type, primarily in Australia, will continue to grow, while the development of laterite-type is expected to be promoted in Indonesia. This is largely driven by the growing demand for nickel in response to the demand for lithium-ion batteries. The global lithium ores are produced in three main types: brine lake (78%), rock/mineral (19%), and clay types (3%). Rock/mineral type has a slightly higher grade compared to brine lake type, but they are less abundant. Chile, Argentina, and the United States primarily produce lithium from brine lake deposits, while Australia and China extract lithium from both brine lake and rock/mineral sources. Canada, on the other hand, exclusively produces lithium from rock/mineral type. Vanadium has traditionally been used in steel alloys, accounting for approximately 90% of its usage. However, there is a growing trend in the use for vanadium redox flow batteries, particularly for large-scale energy storage applications. The global sources of vanadium can be broadly categorized into two main types: vanadium contained in iron ore (81%) produced from mines and vanadium recovered from by-products (secondary sources, 18%). The primary source, accounting for 81%, is vanadium-iron ores, with 70% derived from vanadium slag in the steel making process and 30% from ore mined in primary sources. Intermediate vanadium oxides are manufactured from these sources. Vanadium deposits are classified into four types: vanadiferous titanomagnetite (VTM), sandstone-hosted, shale-hosted, and vanadate types. Currently, only the VTM-type ore is being produced.

• The Korean Journal of Ecology
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• v.28 no.5
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• pp.327-333
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• 2005

For the first time in Korea, plant size, distribution pattern and root growth form of Tamarix chinensis were surveyed at natural stand in Shiwha Lake, from June to July in 2005. T, chinensis grew in the range of 350 m towards north-south and 270 m in east-west direction. The mean number of stems germinated from same root system was 1.9. On the stem base, the numbers of living and dead plants were 1,398 and 114, respectively. Mean perimeter and height of 1,398 plants were $5.9{\pm}3.2$ cm and $159{\pm}51$ cm, respectively. By dividing into 10 classes based on the perimeter size, the largest number of plants were included in the second smallest class category. However, by dividing into 10 classes on the bases of plant height, variation in the number of plants along the height showed normal distribution curve. The heights of dead plants were small in perimeter but diverse in height. On the root base, the number of plants was the greatest in the smallest size class, and conspicuously decreased with size increment. Distribution of T. chinensis was clumped pattern. Age of the largest plant was 8-year. T. chinensis had two types of root growth. One was horizontal growth in the periphery of soil surface, and the other vertical growth.

• Journal of the Korean Geographical Society
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• v.42 no.1 s.118
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• pp.15-26
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• 2007

This study aims to estimate the similarities of lacustrine deposits of lava-dammed Yeoncheon paleo-lake by geochemical analysis such as XRF, ICP-AES, and 14C and OSL age datings in Chugaryeong Rift Valley of Central Korea. OSL age of the lacustrine coastal deposit(YC1) is estimated as 0.11-0.13 Ma. It indicates that paleo-deposits may have remained during at least 20,000 years from 0.13 Ma The origin analysis of deposits were carried out by comparison between lacustrine mud layers($YC1{\sim}2$) and various geomorphic materials of vicinity As a result, the similarity of the origin is highest between the paleo-coastal alluvial deposit of Chatan River(YC8), and surface clay deposit of Jeongok lava plateau(YC9) Next higher similarity is between paleo-lacustrine bottom deposit(YC2) and west valley-side mountain slope colluvial materials(YC5). Another high similarities are among present Chatan River channel sediment(YC7), acustrine coastal deposit(YC1) and east valley-side mountain slope colluvial materials(YC4).

• Journal of the Korean earth science society
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• v.26 no.6
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• pp.560-572
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• 2005

This study investigates the characteristics of atmospheric circulation and the heat source $(Q_1)$ related to the winter cold surge in Korea from 1979 to 1999. The occurrence frequency of cold surge is about one event per year and $60\%$ of the total events occurred during the former period, before 1989. During the cold surge, the pressure pattern shows more dominant east-west dipole circulation pattern in the lower troposphere and the effect of upper level trough is stronger than normal cases. Temperature falling pattern over Korea shows that the pattern opposite to the temperature structure over Lake Baikal and temperature change has opposite signs between the low-middle level and upper level, with the boundary at 400 hPa. The analysis of heat source shows that atmospheric cooling by cold advection during the cold surge is balanced by adiabatic warming due to downward motion, indicating that the movement path of cold core is associated with that of heat sink. Therefore, the movement mechanism of the heat source and sink should be well known for understanding the maintenance mechanism of cold surge and predicting cold surges.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.1
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• pp.1-8
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• 2004

It's a very meaningful experimental study to image restoration of ancient villages vanished at the real life spatial world. Focused on Cheung-Pyung Lake around where most part were flooded by the Chung-Ju large dam founded in early 1980s, we used remote sensing technique in this study in order to restore topographical features before the flood with 3 dimensional effects. It was gathered comparatively good satellite photos and remotely sensed digital images, then its made a new color image from these and the topographical map which had been made before filled water. This task was putting together two kinds of different timed images. And then, we generated DEM(digital elevation model) including the outskirts of that area as harmonizing current contour lines with the map. That could be a perfect 3D image of Cheung-Pyung around before when it had been flood by making perspective images from all directions, north, south, east and west, for showing there in three dimensions. Also, flying simulation we made for close visiting can bring us to experience their real space at that time.

• Parasites, Hosts and Diseases
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• v.57 no.5
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• pp.553-559
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• 2019

The Alataw Pass, near the Ebinur Lake Wetland (northwest of China) and Taldykorgan (east of Kazakhstan), is a natural habitat for wild rodents. To date, little has been done on the surveillance of Bartonella spp. and Wolbachia spp. from fleas in the region. Here we molecularly detected Bartonella spp. and Wolbachia spp. in wild rodent fleas during January and October of 2016 along the Alataw Pass-Kazakhstan border. A total of 1,706 fleas belonging to 10 species were collected from 6 rodent species. Among the 10 flea species, 4 were found to be positive for Wolbachia, and 5 flea species were positive for Bartonella. Molecular analysis indicated that i) B. rochalimae was firstly identified in Xenopsylla gerbilli minax and X. conforms conforms, ii) B. grahamii was firstly identified in X. gerbilli minax, and iii) B. elizabethae was firstly detected in Coptopsylla lamellifer ardua, Paradoxopsyllus repandus, and Nosopsyllus laeviceps laeviceps. Additionally, 3 Wolbachia endosymbionts were firstly found in X. gerbilli minax, X. conforms conforms, P. repandus, and N. laeviceps laeviceps. BLASTn analysis indicated 3 Bartonella species showed genotypic variation. Phylogenetic analysis revealed 3 Wolbachia endosymbionts were clustered into the non-Siphonaptera Wolbachia group. These findings extend our knowledge of the geographical distribution and carriers of B. rochalimae, B. grahamii, B. elizabethae, and Wolbachia spp. In the future, there is a need for China-Kazakhstan cooperation to strengthen the surveillance of flea-borne pathogens in wildlife.

• Journal of the Korean earth science society
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• v.30 no.6
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• pp.721-733
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• 2009

A pattern of tropical cyclone (TC) movement in the western North Pacific area was studied using the empirical orthogonal function (EOF) and the best track data from 1951 to 2007. The independent variable used in this study was defined as the frequency of tropical cyclone passage in 5 by 5 degree grid. The $1^{st}$, $2^{nd}$ and $3^{rd}$ modes were the east-west, north-south and diagonal variation patterns. Based on the time series of each component, the signs of first and second mode changed in 1997 and 1991, respectively, which seems to be related to the fact that the passage frequency was higher in the South China Sea for 20 years before 1990s, and recent 20 years in the East Asian area. When the eigen vectors were negative values in the first and second modes and TC moves into the western North Pacific, TC was formed mainly at the east side relatively compared to the case of the positive eigen vectors. The first mode seems to relate to the pressure pattern at the south of Lake Baikal, the second mode the variation pattern around $30^{\circ}N$, and the third mode the pressure pattern around Japan. The first mode was also closely related to the ENSO and negatively related to the $Ni\tilde{n}o$-3.4 index in the correlation analysis with SST anomalies.