• Economic and Environmental Geology
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• v.28 no.6
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• pp.635-646
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• 1995

Mineralized zone in the Dongyang talc deposits occurs on the lowest dolomite member of the Hyangsanri Dolomite belonging to the Ogcheon Supergroup. Ore bodies are emplaced as pipe-like body along the axis of minor folds plunging $40^{\circ}$ to the west developed in these dolomite layers. Amphibolite and chlorite schist are found along the upper or lower contact of all ore bodies (Kim et al., 1963; Park and Kim, 1966). Following the recrystallization and silicification of dolomite, tremolite and tabular and leafy talc(I) of the earlier stage formed, and microcrystalline talc(II) formed in the later stage. Talc(l) and tremolite formed by the reaction between dolomite and the fluid. Whereas talc (II) formed by the reaction between dolomite and fluid, or by the reaction between early formed tremolite and fluid. During the early stage of mineralization, the fluid was the $H_2O-CO_2$ system dominant in $CO_2$, In the later stage, the composition of the fluid changed to $H_2O-NaCl-CO_2$system, and finally to the $H_2O-NaCl$ system. The pressure and temperature conditions of the formation of tremolite associated with talc(I) were 1,640~2,530 bar, and $440{\sim}480^{\circ}C$, respectively. The pressure and temperature condition of talc(II) ore formation was 1,400~2,200 bar, and $360{\sim}390^{\circ}C$, respectively. These conditions are much lower than the metamorphic pressure and temperature of the rocks from the Munjuri Formation located about 5 km to the noJ:th of Dongyang talc deposit ${\delta}^{13}C$ and ${\delta}^{18}O$ values of dolomite which is the host rock of the talc ore deposit are 2.9~5.7‰ (PDB), and -7.4~l6.8‰ (PDB), respectively. These values are little higher than those from the Cambro-Ordovician limestones of the Taebaeksan region, but belong to the range of the unaltered sedimentary dolomite. ${\delta}^{18}O$and ${\delta}D$ values of the talc from Dongyang deposit are 8.6~15.8‰ (vs SMOW), and -65~-90‰ (vs SMOW), respectively, belonging to the range of magmatic origin. These values are quite different from those measured in the metamorphic rocks of Munjuri and Kyemyungsan Formation. ${\delta}^{34}S$ value of anhydrite is 22.4‰ (CDT), which is much lower than ${\delta}^{34}S$ (30‰ vs COT) of sulfate of early Paleozoic period, and indicates the possibility of the addition of magmatic sulfur to the system. Talc ores show the textures of weak foliation and well developed crenulation cleavages. Talc ore deposit in the area is concluded as hydrothermal replacement deposit formed before the latest phase of the deformations that Ogcheon Belt has undergone.

• Korean Journal of Environment and Ecology
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• v.21 no.1
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• pp.38-46
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• 2007

The vascular plants of the Moaksan provincial park area were listed as 615 taxa: 120 families, 383 genera, 542 species, 1 subspecies, 69 varieties and 3 forms. Based on the list of Korean endemic plants, 6 taxa were recorded: Cephalotaxus koreana, Carex okamotoi, Lilium amabile, Salix purpurea var. japonica, Weigela subsessilis, Aster koraiensis and based on the list of the rare plants by the Forest Research Institute, 5 taxa were recorded in the studied areas: Lilium distichum (Preservation priority order; No. 159), Tricyrtis dilatata (No. 97), Iris ensata var. spontanea (No. 197), Aristolochia contorta (No.151), Viola albida (No. 202). Specific plant species by floral region were a total of 48 taxa; Prunus yedoensis in Class V, 2 taxa, as Carex arenicola, Wistaria floribunda in Class IV, 4 taxa, Spiraea salicifolia, Thea sinensis, Asperula lasiantha, etc. in Class III, 8 taxa, as Lilium distichum, Iris ensata var. spontanea, Acer triflorum, etc. in Class II, 33 taxa, as Camptosorus sibiricus, Orixa japonica, Lonicera praeflorens, etc. in Class I. The naturalized plants in this site were 16 families, 40 genera, 48 species, 2 varieties, 50 taxa and the naturalization rate was 8.1% of all 615 taxa vascular plants. As a conservation measure, there needs to be controls on the imprudent development and excessive visitors and a detailed plan like nature the rest of the year.

• Korean Journal of Plant Resources
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• v.20 no.2
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• pp.201-211
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• 2007

The vascular plants at the nature every second year in Wolchulsan National Park was listed 325 taxa: 86 families, 205 genera, 283 species, 1 subspecies, 36 varieties and 5 forms. Based on the list of the rare plants by the Forest Research Institute, 3 taxa were recorded in the studied areas; Lilium callosum (Preservation priority order; No. 191), Viola albida (No. 202), Wikstroemia trichotoma (No. 120) and based on the list of Korean endemic plants, 8 taxa were recorded; Carex okamotoi, Lilium amabile, Carpinus coreana, Clematis trichotoma, Stewartia koreana, Ajuga spectabilis, Weigela subsessilis, Adenophora triphylla var. hirsute. Specific plants by floral region were total 44 taxa; Prunus davidiana, Wistaria floribunda in class IV, 9 taxa (Neolitsea aciculata, Vaccinium bracteatum, Utricularia racemosa, etc.) in class III, 5 taxa (Bupleurum longiradiatum, Ostericum melanotilingia, Cirsium schantarense) in class II, 28 taxa (Polygonatum falcatum, Eurya japonica, Ajuga spectabilis, etc.) in class I. The naturalized plants in this site were 4 families, 6 genera, 9 taxa and naturalization rate was 2.8% of all 325 taxa vascular plants.

• Korean Journal of Environment and Ecology
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• v.37 no.1
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• pp.35-58
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• 2023

In this study, we conducted a flora survey at Mt.Bakdal (363m) and Mt. Myeongbong (245.3m) in Paju-si, Gyeonggi-do. A total of 405 taxa, including 2 forms, 32 varieties, 8 subspecies, 363 species, 261 genera, and 87 families, were surveyed in the two mountain areas. The ferns were identified as 12 taxa from 6 families, the gymnosperms as 6 taxa from 2 families, the dicotyledonous plants as 290 taxa from 70 families, and the monocotyledonous plants as 97 taxa from 9 families. The remarkable plants included 8 taxa of the Korean endemic plants, which were Populus tomentiglandulosa, Salix koriyanagi, Clematis brachyura, Viola seoulensis, Forsythia koreana, Paulownia coreana, Weigela subsessilis, and Hemerocallis hakuunensis, and 3 taxa of the rare and endangered plants as designated by the Korea Forest Service, including Tylophora floribunda as Vulnerable (VU) species, and Viola albida and Chionanthus retusus as Least Concern (LC) species. The invasive alien plants were 35 taxa, including Rumex crispus, Phytolacca americana, Cerastium glomeratum, Chenopodium album, Chenopodium ficifolium, Lepidium virginicum, Amorpha fruticosa, Robinia pseudoacacia, and Trifolium repens, accounting for 8.5 percent of the 405 taxa of the surveyed plants. We intend to further identify plants through the studies on unsurveyed areas in the western part of the DMZ, identify the native habitats of rare and specialty plants, and use them as basic data for managing ecosystem-disturbing plants.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.4
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• pp.437-446
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• 2012

As a part of establishing suitability classification for forage production, use of the national soil and climate database was attempted for Italian ryegrass (Lolium multiflorum Lam., IRG) in Gangwon Province. The soil data base were from Heugtoram of the National Academy of Agricultural Science, and the climate data base were from the National Center for Agro-Meteorology, respectively. Soil physical properties including soil texture, drainage, slope available depth and surface rock contents, and soil chemical properties including soil acidity and salinity, organic matter content were selected as soil factors. The crieria and weighting factors of these elements were scored. Climate factors including average daily minimum temperature, average temperature from March to May, the number of days of which average temperature was higher than $5^{\circ}C$ from September to December, the number of days of precipitation and its amount from October to May of the following year were selected, and criteria and weighting factors were scored. The electronic maps were developed with these scores using the national data base of soil and climate. Based on soil scores, the area of Goseong, Sogcho, Gangreung, and Samcheog in east coastal region with gentle slope were classified as the possible and/or the proper area for IRG cultivation in Gangwon Province. The lands with gentle or moderate slope of Cheolwon, Yanggu, Chuncheon, Hweongseong, Pyungchang and Jeongsun in west side slope of Taebaeg mountains were classified as the possible and/or proper area as well. Based on climate score, the east coastal area of Goseong, Sogcho, Yangyang, Gangreung and Samcheog could be classified as the possible or proper area. Most area located on west side of the Taebaeg mountains were classified as not suitable for IRG production. In scattered area in Chuncheon and Weonju, where the scores exceeded 60, the IRG cultivation should be carefully managed for good production. For better application of electronic maps.

• Korean Journal of Environment and Ecology
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• v.36 no.6
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• pp.553-565
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• 2022

Awareness of the ecological value and importance of protected areas has increased as climate change accelerates, and there is a need for research on ecosystem services provided by nature. The natural park, which is a representative protected area in Korea, has a system of national parks, provincial parks, and county parks. National parks are managed systematically by the Korea National Park Service, but local governments manage provincial parks and county parks. There may be the same hierarchical differences in naturalness (habitat quality) depending on the hierarchy of the natural parks, but it has not been verified. To identify differences, we examined 22 mountain-type natural parks using habitat quality using the INVEST model developed by Stanford University. The analysis of the habitat quality, regardless of the type and area of the natural park, showed that it was higher in the order of Taebaeksan National Park (0.89), Juwangsan National Park (0.87), Woongseokbong County Park (0.86), and Gayasan National Park (0.85). The larger the area, the higher the value of habitat quality. A comparison of natural parks with similar areas showed that the habitat quality of national parks was higher than that of provincial parks and parks. On the other hand, the average habitat quality of county parks was 0.83±0.02, which was 0.05 higher than that of provincial parks at 0.78±0.03. Furthermore, the higher the proportion of forest areas within the natural park, the higher the habitat quality. The results confirmed that the naturalness of natural parks was independent of their hierarchy and that there are differences in naturalness depending on land use, land coverage, and park management.

• Korean Journal of Environment and Ecology
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• v.30 no.2
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• pp.173-184
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• 2016

Knowledge of the relationships among interspecific competition, spatial distributions and ecological niches plays an important role in understanding biogeographical distribution patterns of species. In this study, the distributional characteristics and ecological niches of the three Viperidae species (Gloydius ussuriensis, G. brevicaudus, and G. saxatilis) in South Korea were determined based on observation data and species distribution model. The effects of interspecific competition on geographical distribution and the division of the ecological niches of the vipers were also examined based on the models of predicted species distribution. The results showed that altitude was the most important environmental variable for their distribution, and the altitudes at which these snakes were distributed correlated with the climate of that region. Although interspecific ecological niches are quite overlapped, their predicted distribution patternsvary by the Taebaek Mountains. When overlaying the distribution models, most of the overlapping habitats were forest areas, which were relatively less overlapped than were the entire research areas. Thus, a parapatric distribution pattern was expected. The abundance of species occurring sympatrically was positively correlated with each other, indicating the lack of serious interspecies competition in this region. In conclusion, although the three Viperidae species in South Korea occupy similar ecological niches, these snakes exhibit parapatric distribution patterns without direct competition. Further research on various geographic variables (e.g., altitude, microhabitat characteristics) using relatively fine grid sizes, as well as further detailed ecological and behavioral research, is needed to determine the causative factors for the parapatric distribution pattern.

• Economic and Environmental Geology
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• v.43 no.5
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• pp.477-490
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• 2010

The Gagok stratabound skarn deposit is the result of the intrusion of the Cretaceous granitic pluton into the Paleozoic calcareous rocks. The subvolcanic intrusion ranges in composition from quartz monzonite to granite porphyry with I-type, calc-alkaline and weakly peraluminous characteristics. Both endoskarn and exoskarn are developed at the Gagok Zn-(Pb) deposit, with more exoskarn than endoskarn. Geochemical and mineralogical characteristics in the Seongok and Wolgok orebodies can be treated in terms of self-organization. Sphalerites in the Gagok ore can also incorporate minor amounts of Mn, Cd, Cu and In. Trace element concentrations in different orebodies vary because fractionation of a given element into sphalerite is influenced by formation temperature and the amount of sphalerite in the ore. A group of high In/Zn and Cd/Zn ratios in ores, and low Mn/Fe ratios in sphalerites are correlated with proximal processes of a magmatic source. The pattern of minor/trace element variations in ores and sphalcrites can be used for petrogenetic interprctation, e.g., orebody zonation related to crystallization temperature and fluid d sources.

• Journal of Conservation Science
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• v.30 no.4
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• pp.345-351
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• 2014

Chemical and Pb isotope analysis were performed in order to determine the origin of bronze artefacts excavated from the Inyongsaji site in South Korea. The result of ICP-MS shows that they are tin bronzes in which lead was not intentionally added during production. Pb isotope data analyzed by TIMS are plotted in the southern region of Korea and China of the distribution map drawn by Mabuchi(1985). On the other hand, the identical isotope data are plotted in the Taebaek basin and the Olcheon metamorphic belt correspondent to zone2 and zone3 respectively. It is believed that the isotope data on the tin bronzes which have very low lead content can be used to trace the origin of copper ore rather than those of either lead or tin ore. Pb istope analysis allows diverse interpretation as it can be applied to any object containing trace amounts of lead. In addition, accumulation of isotope data as well as further studies will improve reliability of the provenance studies.

• Journal of the Mineralogical Society of Korea
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• v.25 no.4
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• pp.221-231
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• 2012

Uljin cassiterite deposit had been known to be a pegmatitic origin derived from the Wangpiri (Buncheon) granitic gneiss of Precambrian period. Lithium ore also shows the same origin and its lithium bearing mineral was ascertained to be a taeniolite. But the presence of leucocratic granites which played the role of host rocks haven't been clearly designated yet in these provinces. Even though Bonghwa and Youngweol sericite deposits situated in the vicinities of Hambaeg syncline had been known to have their host rocks as Hongjesa Granites of Precambrian period and Pegmatitic migmatite of unknown age respectively. But younger leucocratic granites are characterized by more amounts of albite and sericite (muscovite-3T type) than those of the older granitic rocks which contain plenty of biotite and chlorites. Although the younger granites show rather higher contents of alkalies such as $Na_2O$ (0.13~8.03 wt%) and $K_2O$ (1.71~6.38 wt%), but CaO (0.05~1.21 wt%) is very deficient due to the albitization and greisenization. Manisan granite, which is assumed to be Daebo granite which intruded the Gyunggi Gneiss Complex was again intruded by leucocratic granite whose microclinized part changed into kaolins. Taebaegsan region shows a wide distribution of carbonate rocks which are especially favorable to the ore depositions. And the presence of alkali granites which formed in the later magmatic evolution are well known to be worthwhile to the prospections of various rare metals and REEs resources.