• Journal of Korean Society of Forest Science
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• v.112 no.4
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• pp.502-514
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• 2023

This study was conducted to understand the long-term changes in soil physiochemical properties and seedling growth in Larix kaempferi (larch) stands planted in clear-cut larch and Pinus rigida (pine) forest soils over an 11-year period after reforestation. Two-year-old bare-root larch seedlings were planted in 2009-2010 at a density of 3,000 seedlings ha^-1 in clear-cut areas that harvested larch (Chuncheon and Gimcheon) and pine (Wonju and Gapyeong) stands. We analyzed the physiochemical properties of the mineral soils sampled at 0-20 cm soil depths in the planting year, and the 3^rd, 7^thand 11^th years after planting, and we measured seedling height and root collar diameter in those years. We found significant differences in soil silt and clay content, total carbon and nitrogen concentration, available phosphorus, and cation exchangeable capacity between the two stands; however, seedling growth did not differ. The mineral soil was more fertile in Gimcheon than in the other plantations, while early seedling growth was greatest in Gapyeong. The seedling height and diameter at 11 years after planting were largest in Wonju (1,028 tree ha^-1) and Chuncheon (1,359 tree ha^-1) due to decreases in stand density after tending the young trees. The soil properties in all plantations were similar 11 years after larch planting. In particular, the high sand content and high available phosphorus levels (caused by soil disturbance during clear-cutting and planting) showed marked decreases, potentially due to soil organic matter input and nutrient uptake, respectively. Thus, early reforestation after clear-cutting could limit nutrient leaching and contribute to soil stabilization. These results provide useful information for nutrient management of larch plantations.

• The Korean Journal of Malacology
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• v.30 no.2
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• pp.107-116
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• 2014

Gonadal development and maturation mechanism were studied on the freshwater marsh clam Corbicula papyracea (Heude), which is the endangered species in Korea. The specimens were collected in the rearing ponds and waterway of NFRDI in Gapyeong-gun, Gyeonggi-do from January to December 2004, and then investigated by condition factor, relative growth, gonadal development phases and gonad histological characters based on 30-50 individuals every month. Comparing with the freshwater marsh clam, C. papyracea is small, light olive brown shell and violet interior. The hermaphrodite individuals of C. papyracea take an internal fertilization and fertilized eggs are stored in the foster-sack in the gills, then the hatched juveniles are released outside after an ovoviviparous process. The average water temperature of inhabit area was in range of $1.8-27.0^{\circ}C$ and usually took great effects on the gonad maturation of C. papyracea. The condition factor ranged from 0.14 to 0.21 throughout the year, which was the lowest during winter season (December-February), and gradually increased to the highest value of 0.21 in May. The ratio of meat weight to total weight was 25.9-38.7%, indicating the similar trend with condition factor. The highest values of condition factor and the ratio of meat weight appeared 1-2 months later than gonadosomatic index reached the peak value, it was probably because that the ovoviviparous eggs would spend a long period before hatching from the foster-sack in the gills. To synthesize the characters of meat weight, condition factor and gonad development by histological study, reproductive cycle of C. papyracea could be divided into five successive stages: multiplicative stage (December to February), growing stage (February to May), mature stage (June to August), spawning stage (August to November), recovery stage (November to December). The smallest shell length of matured C. papyracea was 12.6 mm, and individuals, larger than 16 mm, was formed the nursery in the gills.

• Korean Journal of Ichthyology
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• v.29 no.3
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• pp.176-189
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• 2017

Age estimation and sexual dimorphism of Coreoleuciscus splendidus were estimated using otolith, length-frequency distribution and 23 morphological measurements, from 245 individuals collected from September 2016, February and April 2017 in the Gapyeong stream, Han River, Korea. Result of age estimation of C. splendidus, we most examined were 2, 3 and 4-age, and the maximum observed ages were 5-age. Nine out of twenty-three morphometric measurements were significantly different between the genders. Anal fin have showing major sexual dimorphism in particular between adult individuals. This sexual dimorphism was based on extension of anal fin soft rays of male individuals. Therefore anal fin of males is always longer and wider than females. During spawning season male individuals possess nuptial tubercles on anal fin rays. However, another measurements and morphological characters does not exhibit sexual dimorphism in the between male and female individuals. The sexual dimorphism was observed to only over 2-years old individuals with sexual maturity. But juvenile and 1-years old individuals do not have sexual dimorphism with sexual maturity. Peak season of spawning was April to May and they start first spawning at 2-age. The ages at major spawning groups were most 3-age, and they maximum GSI index was 14.91 (female), 8.96 (male) at 5-age, respectively.

• Korean Journal of Plant Resources
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• v.23 no.5
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• pp.480-485
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• 2010

This study reports on the morphological characteristics and distribution for conservation and practical use in the Korean Peninsula of Chrysosplenium flaviflorum through a comparison with relative species. The morphological characters that were newly investigated in this study included subhypogaeus stolons and glabrous on the surface of leaves. The former has not been described by any taxonomist who had previously treated this species with the exclusion of Hara. Despite this, the latter is a very important key to using the identification of varieties of Ser. Pilosa though there were no descriptions which included Ohwi. C. flaviflorum Ohwi which was endemic and known to be distributed only in the northern area of the Korean Peninsula, was also observed in the Gapyeong-gun, Gyeonggi-do, Cheorwon-gun, Gangwon-do, and Yeongdonggun, Chungcheongbuk-do middle area since the latest collection report in 1943. There is a requirement for further study to be conducted on the distribution and management by designation for the Special Plant Species by the Korean Ministry of Environment.

• Journal of the Korean Geographical Society
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• v.50 no.5
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• pp.485-503
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• 2015

This study aims at evaluating geomorphological classification systems to predict the occurrence of landslides in mountainous region in Korea. Geomorphological classification systems used in this study are Catena, TPI, and Geomorphons. Study sites are Gapyeong-gun, Hoengseong-gun, Gimcheon-si, Yeoju-si/Yicheon-si in which landslide occurrence data were collected by local governments from 2001-2014. Catena method has objective classification standard to compare among regions objectively and understand the result intuitively. However, its procedure is complicated and hard to be automated for the general public to use it. Both TPI and Geomorphons have simple procedure and GIS-extension, therefore it has high accessibility. However, the results of both systems are highly dependent on the scale, and have low relevance to geomorphological formation process because focusing on shape of terrain. Three systems have low compatibility, therefore unified concept are required for broad use of landform classification. To assess the effectiveness of prediction on landslide by each geomorphological classification system, 50% of geomorphological classes with higher landslide occurrence are selected and the total landslide occurrence in selected classes are calculated and defined as 'predictive ability'. The ratio of terrain categorized by 'predictive ability' to whole region is defined as 'vulnerable area ratio'. An indicator to compare three systems which is predictive ability divided by vulnerable area ratio was developed to make a comprehensive judgment. As a result, Catena ranked the highest in suitability.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.23 no.3
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• pp.202-215
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• 2010

Objective : This study was performed to investigate the prevalence of otolaryngology and respiratory diseases and characteristics of the outpatients who had visited Chuncheon oriental medical hospital which located in Gangwon province with the diseases. Methods : We analyzed data from 627 patients, who had visited to the Department of ophthalmology & otolaryngology & dermatology of Chuncheon oriental medical hospital from November 1st, 2007 to May 31th, 2010. The data were analyzed and demonstrated by age, gender, season, period between the onset of disease and the first examination, times of treatment, and treatment methods. Results : The results of this study are summarized as follows. 1. Among the 627 outpatients, male patients outnumbered female patients, and the most frequent age group was 0-10 year-old group(24.9%) and it is followed by 31-40 and 41-50 year-old groups. The majority of outpatients, 79.7% of them were from Chuncheon, and Hongcheon and Gapyeong residents were respectively 4.7% and 3.8% of the patients. 2. The shares of outpatients by department were 47.4% in Rhinology disease, 29.8% in respiratory disease, 14.5% in Otology disease, and 8.3% in Laryngology disease. The seasons with the most frequent prevalence by department were spring and winter for otology group, autumn and spring for rhinology group, summer and spring for laryngology group, and winter and spring for respiratory disease group. Overall, most outpatients had visited the hospital for 1-5 times or 6-10 times. Acupuncture and herbal medicine were the most frequent treatment methods that these patients received. 3. The most prevalent diseases were rhinitis, common cold, tinnitus, and sinusitis. The most frequently visited age groups for tinnitus and hearing loss were 41-50 and 51-60 year-old groups, and for rhinitis and sinusitis 0-10 and 11-20 year-old groups. Irritation in larynx was almost evenly prevalent among 31-40, 41-50 and 51-60 age groups. Regarding the period between the onset of disease and the first medical examination, outpatients with tinnitus, rhinitis, sinusitis, and irritation in larynx came to the hospital after one year since the onset and outpatients with common cold first visited the hospital within one week since the onset of disease. Conclusions : This study shows that the most frequent diseases were rhinitis, common cold, sinusitis, tinnitus, and cough. In order to do better treatment for these diseases in the future, there is a need to investigate long-term, multifaceted studies, connected studies with other hospital in Gangwon province.

• The Journal of the Petrological Society of Korea
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• v.2 no.1
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• pp.1-8
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• 1993

We report on kyanite newly found in the Yongduri gneiss complex of the Chuncheon-Hongcheon area, central Gyeonggi massif. Major mineral assemblage of quartzofeldspathic gneisses in the study area consists of biotite+ garnet+ sillimanite + plagioclase+ quartz${\pm}$kyanite${\pm}$K-feldspar${\pm}$muscovite. Kyanite occurs in four samples, and coexists with sillimanite in three of these samples. In most cases, kyanite is anhedral to subhedral, ranges up to Imm in the maximum dimension, and occurs as metastable relict grains. These observations indicate that the Yongduri gneiss complex has experienced a medium-pressure type metamorphism, followed by low-pressure type one belonging to the sillimanite+K-feldspar zone. Average temperature and pressure of the peak metamorphism are $683{\pm}62^{\circ}C$ and 4.9-5.5 kbar, respectively, when the existing chemical data are re-interpreted. In conjunction with the finding of kyanite in the Cheongpyeong-Gapyeong area (Lee and Cho, 19921, this study demonstrates that kyanite may occur regionally in central Gyeonggi gneiss complex. Moreover, the persistence of kyanite even after the high-T metamorphism of the sillimanitetK-feldspar zone suggests that the central Gyeonggi massif has experienced a tectonometamorphic evolution characterized by a rapid uplift.

• Korean Journal of Ecology and Environment
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• v.41 no.3
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• pp.367-373
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• 2008

A freshwater bivalve (Unio douglasiae) was examined to assess the filtering rate (FR) on the cyanobacterial assemblage in a hypertrophic lake. Animal U. douglasiae used in the present study was collected using a hand-operated dredge from the North Han River (Gapyeong, Korea). The FR was measured at different feeding conditions such as feeding interval (1, 4, 7, and 24 h), mussel size (4.2$\sim$8.1 cm, n=23), prey concentration (506.7, 409.8, 327.5, 199.7 and 88.6 ${\mu}g\;L^{-1}$), and mussel density (0.5, 1.0 and 1.5 indiv. $L^{-1}$). On the applied feeding interval, the maximum FR (0.21 L $g^{-1}h^{-1}$) and minimum feces production (FP, 0.12 mg $g^{-1}h^{-1}$) were observed at 1 and 24 hr, respectively. Both weight-based FR and FP were not correlated with the mussel size, and the values lied in a limited range with some degree of variation. Likewise, no significant relations between FR and FP were observed in the mussel size. The FR values were negatively correlated with food concentration, but positively with FP. For the food concentrations, the maximum FR (0.41 L $g^{-1}h^{-1}$) and FP (0.16 mg $g^{-1}h^{-1}$) were 88.6 ${\mu}gL^{-1}$ and 327.5 ${\mu}gL^{-1}$, respectively. These results indicate that U. douglasiae collected from the North Han River, although the filtering rate were slightly less than Keum River mussel, may be applied as a strategic bio-filter to mitigate cyanobacterial bloom in eutrophic lake.

• Journal of Wetlands Research
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• v.22 no.2
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• pp.113-120
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• 2020

For the conservation of both Sericinus montela (vulnerable species by red book of Korea) and A. contorta, we investigated environmental factors affecting the growth and reproduction of Aristolochia contorta. We selected four A. contorta habitats at Gapyeong, Pyeongtaek, Cheongju, and Yeoju in Korea and surveyed community and habitat characteristics of companion species, herbivore appearance, support types, and soil physicochemical properties in July and October, 2018. Habitat environments and the growth and reproduction characteristics of A. contorta were different according to four habitats of different regions. In particular, the fastest growth speed and earliest flowering and fruiting were observed in Pyeongtaek. Growth of A. contorta in Cheongju and Yeoju were interrupted by aboveground damage from human disturbance. In this study, support types seemed to be important for growth speed of A. contorta. Flowering and fruiting timing were likely to be related to combined effects of soil cation contents and competitive and herbivore stresses. Therefore, providing effective support and reducing biological stress should be necessary for stable growth and proper flowering and fruiting timing of A. contorta. In addition, experimental evidence would be needed to figure out the effect of soil cation and biological stress on flowering and fruiting of A. contorta in detail.

• Journal of the Mineralogical Society of Korea
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• v.19 no.4 s.50
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• pp.325-336
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• 2006

Domestic serpentinite is one of the important industrial minerals utilizing in the iron manufacturing company such as POSCO in Korea. Serpentinite is distributed in the Ulsan Fe deposit, Andong, Hongseong-Cheongyang, and Gapyeong areas. This study tries to interpret the relationship among the formation of carbonate rocks, iron mineralization, and serpentinite alteration throughout the study of field occurrence, mineralogy, and chemical compositions. Serpentine is formed by the break-down of olivine and pyroxene of parent peridotite. The serpentinization is inferred to be formed by the hydrothermal fluid derived from intruded Cretaceous granite and the addition of meteoric water. Variation of major oxides such as $SiO_2,\;Fe_2O_3$, and MgO in serpentinized rocks are controlled by the degree of serpentinization and Fe mineralization. Variation of $Al_2O_3$ and CaO contents of altered rocks is dependent on the amount of the residual minerals such as calcite and homblende, and on the degree of chloritization. The presence of carbonate rocks reported in the sedimentary origin or igneous origin (carbonatite) provided a geological environment to form skarn type Fe deposit regardless of its origin. The geological processes of Ulsan Fe deposits are inferred to be formed as the order of the formation of carbonate rocks ${\to}$ the intrusion of Cretaceous granite ${\to}$ serpentinization ${\to}$ Fe mineralization by the interprelation of field occurrence and mineralogical characteristics.