• The Journal of the Petrological Society of Korea
• /
• v.27 no.4
• /
• pp.185-194
• /
• 2018

The basaltic rocks of Daljeon-ri columnar joint (Natural Monuments # 415) and Noeseongsan Noerok site (Natural Monuments # 547) were analysed in order to understand basalt types of two areas. The basaltic rocks of the Pohang Daljeon-ri columnar joint show a typical porphyritic texture containing phenocrysts (olivine and clinopyroxene) and groundmasses composed of clinopyroxene, plagioclase, and opaque minerals,. In contrast, basaltic rocks of Noeseongsan Noerok are characterized by fine-grained groundmass with large phenocrysts of plagioclase. Other analysis such as magnetic susceptibility, X-ray diffraction and X-ray fluorescence also support the petrological differences of two basalt rocks. The Daljeon-ri basaltic rocks are plotted on phonotephrite volcanic rocks of alkaline series in TAS(total alkali silica), and on within plate basalt in Zr-Ti diagram. The Noeseongsan basalts, on the other hand, are plotted on basaltic andesite to andesite of sub-alkaline series in TAS, and on volcanic arc basalt in Zr-Ti diagram. These results indicate that the original mantle materials between two basalt rocks were different each other, which probably originated from the change of a tectonic setting in the southeastern Korean peninsula during the Miocene.

• Korean Journal of Heritage: History & Science
• /
• v.44 no.4
• /
• pp.130-141
• /
• 2011

This paper examined the bleaching effect of the two types of gel made with neutralizing agent such as sodium meta silicate gel & triethylamine gel mixed with carbopol resin 940 & 934 which has thickness effect in broad pH region and mixed with 10% hydrogen peroxide. Sodium meta silicate gel(1.6g included) provided pH 10, the most suitable environment for bleaching. The result of comparison of the baseline colour changes(${\Delta}E*ab$) and colour changes according to time(${\Delta}E*ab$) is as following. Group1(carbopol 940, sodium meta silicate, Urea Hydrogen Peroxide) showed 112% efficiency at CS-2; 63.3% at CS-4; 87.4% at CS-6. Group2(carbopol 934, sodium meta silicate, Urea Hydrogen Peroxide) showed 77.3%, 67.3%, 109.6% at CS-8, CS-10, CS-12 respectively; CT-1, CT-3, CT-5 of Group3(carbopol 940, triethylamine, Urea Hydrogen Peroxide) showed 36.8%, 73.2%, 74%; In Group4(carbopol 934, triethylamine, Urea Hydrogen Peroxide), efficiency of CT-6, CT-8, and CT-10 was 81.7%, 95.4%, and 95.7%. The paper showed that various concentration of neutralizing agent such as sodium meta silicate and triethylamine have bleaching effect. Viscosity of the gel including sodium meta silicate was higher than the gel including triethylamine. High viscosity helps the bleaching gel sit on the smooth slope of the ceramics. As a result, sodium meta silicate is considered to provide thickening and bleaching effect required in producing 10% hydrogen peroxide gel.

• Korean Journal of Heritage: History & Science
• /
• v.43 no.1
• /
• pp.28-55
• /
• 2010

Currently, the natural monument system of Korea for naming and designation of natural monuments is based on "Chosun Natural Monument Conservation Acts for Treasure, Ancient Landmark, and Natural Beauty" enacted in 1934 during Japanese colonization period. The framework of natural monument system is still in effect, which is pointed out as a problem. The Dangsan forests and Bibo forests are Korean traditional cultural resources representing countryside of Korea. Cultural Heritage Administration follows and relies on the 'Limsu of Chosun' (1938), a report written by a Japanese, for naming and classification of natural monuments. A Dangsan forest at Yesong-ri was named "Yesong-ri evergreen forest" in 1938. They followed the naming system of "evergeen forest" until today. The objective of this study is to review the issues and problems of 'Limsu of Chosun' and natural monument naming system begun during Japanese occupation period, and suggest an alternative to the current situation where naming natural monument accordingly without discretion. Eighteen dangsan forests bibo forests were selected for examination and analysis. The names of the dangsan forests bibo forests were evaluated to find out whether various aspects of the forests are reflected in the name. The study suggests that many forests and old trees designated as natural monument should be named as "~Dangsan forest", "~Dangsan forest Bibo forest", or "~Dangsan tree" with consistency accordingly. The new names will bring a momentum to overcome the limitation of natural monument naming system continued since Japanese occupation period, and also enhance the value of Dangsan forests and Bibo forests as Korean traditional and cultural landscapes.

• Korean Journal of Environment and Ecology
• /
• v.33 no.3
• /
• pp.321-332
• /
• 2019

The purpose of this study is to identify the problems and present the improvement measures by assessing the suitability of planning of provincial natural parks on a legal basis. We assessed the suitability of 29 provincial parks to examine the suitability of park planning (special-purpose district planning and facilities planning) according to the Natural Park Act, implementation of the park projects, and registration of Korea Real estate Administration intelligence System (KRAS) for park management and obtained the following results. In the case of the park nature conservation districts among the special-purpose districts, 24.1 % (7 parks) were not feasible or decided the park facility that was larger than the planned area. The amended law requires the park cultural heritage district as a new special-purpose district, but 41.2% did not designate the district or failed to comply with the standard. Moreover, there was a problem of establishing or announcing the plan that was unsuitable for the management of park village district (former collective facilities district). Although provincial parks are categorized as the restricted area, the park facility plans still focus on regional development and tourism development, and the titles (names) of the park facilities are wrong. The law requires digitalization and disclosure of park plans, but many parks fail to abide by the law. We judge that it is necessary to develop effective provincial park planning and establish the measures to protect and manage the provincial parks.

• Korean Journal of Environment and Ecology
• /
• v.33 no.3
• /
• pp.292-302
• /
• 2019

This study conducted a hierarchy analysis based on a questionnaire survey of experts in park management, ecosystem survey, and ecological environment planning to establish evaluation items and a weighing value of each item to develop ecological connectivity in Baekdudaegan mountain range neighboring the Taebaeksan National Park using the AHP approach. We selected four high-level evaluation indexes and 13 low-level evaluation indexes through literature review and interview with the people in the field and calculated weights for each question through the consistency analysis. The analysis showed that increasing the ecological value was the most important item with the index of 0.474 among the high-level evaluation items, followed by the mitigation of human-nature conflict at 0.247, participation by local residents at 0.165, and the economic perspective at 0.114. Among the low-level evaluation indexes, the movement route of wildlife was the highest at 0.116, followed by the connectivity of landscape ecological patch at 0.112, and functional habitat at 0.099. The comparison of the evaluation items in each working group and the weight factors showed that the movement route of wildlife was the most important at 0.116 in ecosystem survey, the functional habitat was the most important at 0.110 in park management, and the regional preservation and distribution of resources was the most important at 0.123 in ecological environment planning. The results of this study is useful to identify evaluation items for developing ecological network with a diverse source of the actual environmental data in the Taebaeksan National Park.

• Korean Journal of Environment and Ecology
• /
• v.33 no.4
• /
• pp.402-407
• /
• 2019

In this study, we investigated the habitat characteristics of a reservoir in Gyeongju City, Gyeongbuk, in which a large group of Mauremys reevesii (endangered species Class II and natural monument No. 453 in Korea) was discovered. We examined the biotic and abiotic factors that directly and indirectly threaten the survival of M. reevesii within the habitat. The reservoir where M. reevesii was discovered was built for agriculture and surrounded by submerged trees, dam, forests, reeds, and farmland (paddy field). All of the M. reevesii were found only in the submerged trees on the north side of the reservoir. We found 28 M. reevesii (8 juveniles) and 21 M. reevesii (16 juveniles) from field surveys on May 10th and August 9th, 2018, respectively. A number of red-eared sliders (Trachemys scripta elegans) and American bullfrogs (Rana catesbeiana), which threaten the survival of M. reevesii, were also found in and around the reservoir. Moreover, there were signs of excavation of cultural asset, chemical fertilizer, and household garbage, all of which are considered to be major threats to the survival of M. reevesii, all over the reservoir. Newborn turtles in this year were not observed. However, we estimated that natural breeding had sufficiently occurred since we observed many young turtles in the reservoir. Furthermore, the presence of young T. s. elegans individuals can be a persistent problem for M. reevesii as they are competing species. In conclusion, in-situ conservation method should be considered for protecting the endangered turtle and their habitat.

• Korean Journal of Environmental Biology
• /
• v.39 no.3
• /
• pp.273-288
• /
• 2021

We analyzed the spatio-temporal distribution characteristics of water quality and phytoplankton communities in the Isa Stream systems (ISS) from Sangsa Lake to Suncheon Bay. Sangsa Lake showed relatively oligotrophic and mesotrophic conditions, but the freshwater and mixed brackish water zones showed more severe eutrophication than Sangsa Lake and Suncheon Bay due to the influence of industrial waste such as livestock waste. In terms of the phytoplankton community, the number of phytoplankton species was higher in freshwater and mixed brackish water zones than in Sangsa Lake and Suncheon Bay, but the cell density and Chlorophyll-a concentrations (Chl-a) were relatively high in Sanga Lake and Suncheon Bay. In particular, the mesotrophic species Fragilaria crotonensis and Asterionella formosa showed different dominance in the surface and bottom layers, and the influence of A. formosa was significant in the freshwater and mixed brackish water zones in spring and summer. However, Skeletonema costatum-ls, a eutrophic indicator species, dominated in mixed brackish water zones to seawater in autumn and winter. Thus, the severe eutrophication and rapid environmental changes in the ISS could seriously damage the coastal ecosystem in Suncheon Bay. These ecosystem changes are threatening in terms of conservation and management of the UNESCO Suncheon Biosphere Reserve and Yeoja Bay including Suncheon Bay, which recorded the first Ramsar wetland in Korea. Therefore, further research is needed to establish an in-depth management plan.

• Fisheries and Aquatic Sciences
• /
• v.24 no.1
• /
• pp.19-31
• /
• 2021

Seaweeds are a potential source of minerals, essential amino acids, fatty acids, proteins, and various bioactive compounds such as antioxidants. The higher water content of seaweeds reduces the shelf life and this requires the appropriate drying method. The drying conditions play a major role in the conservation of nutrient composition in dried seaweeds. In recent years, the seaweed industry has used many different drying methods with advantages and limitations. Hybrid hot-water Goodle dryer (HHGD) which is a special dryer mixed with hot-water and a Korean traditional heating system (Goodlejang) might be a solution to avoid these limitations. The present study evaluated the effect of drying conditions in HHGD on nutrient composition and bioactivities of brown seaweeds. Moreover, freeze-dryer (FD) and HHGD were employed in this study to compare the dried outputs obtained from four brown seaweed species. The present study aims to evaluate the effect of the hybrid hot-water Goodle drying method (HHGDM) on the nutritional composition and antioxidant activity of dried seaweeds. AOAC standard methods were used to analyze the proximate composition of dried samples and their 70% ethanol extract. The intracellular and extracellular antioxidant activities were evaluated using Vero cells and electron spin resonance (ESR) spectrometer respectively. High performance liquid chromatography, apoptotic body formation, and in-vivo experiments were used for further confirmation of the quality of dried output. The proximate composition results obtained from drying in HHGD and FD did not exhibit any significant difference. Moreover, the seaweed extracts from the dried seaweeds by HHGD and FD dryings were also not different and both significantly down-regulated in-vivo and in-vitro oxidative stress. Furthermore, the high performance liquid chromatography results revealed that the two dryers did not make the major peaks different in the chromatograms. Freeze-drying method (FDM) provides elevated quality for dried output, but there are limitations such as high cost and low capacity. The results from a novel HHGD did not provide any significant difference with the results in FD and expressed a potential to avoid the limitations in FD. Overall, these findings solidified the applicability of HHGD over FD.

• Korean Journal of Environmental Biology
• /
• v.39 no.2
• /
• pp.207-217
• /
• 2021

Using the data from the national survey of fish, we determined the population size and the distribution of Micropterus salmoides, which is a translocated species into the aquatic ecosystem of Korea. . The spatial concentration of this species was determined by performing an optimized hot spot analysis. After determining potential invasiveness and risk assessment, we measured the disturbance of biodiversity in the aquatic ecosystem. The result of distribution analysis indicates that the population of M. salmoides was concentrated in the major basins of Han river, Geum river, Nakdong river, and Yeongsan-Seomjin river, including the Jeju island. In particular, Nakdong river basin showed the highest appearance rate. On the contrary, Yeongsan-Seomjin river basin showed the lowest appearance rate. The Nakdong river and the Nakdong river basin were the areas with the high spatial concentration of M. salmoides. On the other hand, only Han river basin and Geum river basin had the lowest spatial concentration. The fish invasiveness screening kit(FISK) was used to assess M. salmoides, which inhabited a broad region of aquatic ecosystem: the assessment score was 31.0, indicating its 'highly invasive' nature. Our study aims to encourage research that improves the biodiversity and the conservation of M. salmoides in a priority area.

• Korean journal of applied entomology
• /
• v.59 no.4
• /
• pp.433-441
• /
• 2020

This study was conducted to understand the distribution characteristics of aquatic insects in ecologically different ponds in terms of the disruption. We investigated the fauna of aquatic insects in three artificial ponds (pond 1, 2 and 3) and two natural ponds (pond 4 and 5) located within 1 km each other around Gungdaeoreum in Jeju Island, from March 2018 to June 2020. A total of 50 species belonging to 15 families were found in the surveyed ponds: total 850 individuals with 14 species in 4 families of the order Odonata, total 4,391 individuals with 14 species in 6 families of the order Hemiptera, and total 2,014 individuals with 22 species in 4 families of the order Coleoptera. In overall, total abundance and species numbers were relatively higher than those of artificial pond in natural ponds in which animal and plant ecosystems were well established. In the case of artificial ponds, the number of individuals and species recovered rapidly when reconstituted by introducing aquatic plants, etc. (Pond 1). The nymphs of Odonata were observed largely in ponds without natural enemies such as large fish, and where adults could freely access without interception by artificial structure. Phytophagous Corixidae of the order Hemiptera were abundant, and Haliplidae populations of the order Coleoptera were affected by the distribution of the plants. Accordingly, the major factors affecting aquatic insect abundance were identified as the presence of refuges such as the topography and aquatic plants and presence of predators. Species of the order, Odonata were vulnerable based on these factors. Our results can be useful as basic information for the restoration of wetlands and construction of artificial wetlands or for conservation of species diversity in the future.