• Journal of Wetlands Research
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• v.17 no.3
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• pp.264-272
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• 2015

Understanding bird status is essential for the systematic and sustainable management of the Nakdong River Estuary, taking into consideration the relationship between ecosystems and the bird species. In this study, bird status in the Nakdong River Estuary Bird Sanctuary prior to the Four Major Rivers Project was analyzed using the bird monitoring data (2003-2011) from surveys conducted by the Busan Development Institute. The high percentage of winter visitors in terms of both species diversity (38.36%) and individual bird numbers (63.14%) suggest that the Nakdong River Estuary is an important wintering site for migratory birds. Cumulative numbers of individual birds were higher in Myungji (208,601), West Nakdong River (202,444), Eulsukdo (153,232), and Baekhap Doyodeung (150,595). The total numbers of migratory species were higher in Eulsukdo (171), Ilungdo (124), Myungji (132), and Samrak (121). Among the 232 species found in the Nakdong River Estuary, Anas platyrhynchos (17.71%) was the most common species, followed by Anas poecilorhyncha (8.85%), Larus crassirostris (6.48%), Anser fabalis (6.09%), Anas penelope (5.16%), and Calidris alpina (4.22%). Most bird taxa, except shelducks, showed annual fluctuations in individual numbers, with increasing frequency during survey periods. Of these, cormorants, swans, and gulls showed higher fluctuations than other taxa. Swans decreased drastically in numbers in 2007-2008 and 2009-2010 compared to previous years. Shore birds, gulls, wagtails, and other forest birds were also less common in 2010-2011. These results suggest that there were some environmental changes that might have affected the birds in the Nakdong River Estuary. Overall, the results suggest that habitat types affect the distribution of dominant species.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.4
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• pp.237-244
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• 2006

The SMG project has been driven to secure food and water resources by closing of the SMG dyke for the preparation of the unification of Korean peninsular. It was investigated for pollution loads, land use distribution and water consumption for environmental assessments in two watersheds, the Mankyeong River (MK) and the Dongjin River (DJ) to assess the role of agricultural land on the alleviation of pollution loads to the SMG basin. It is needed to give the priority in managing pollution sources to conserve freshwater in the Saemangeum (SMG) basin after the completion of the SMG reclamation from tideland. The MK has $700million\;m^3$ water of which 14.1% were used for living, 73.6% for agriculture and 12.3% for industry. The DJ has $505million\;m^3$ water of which 3.0% for living, 94.5% for agriculture and 2.5% for industry. As compared to proportion of each land of total area, agricultural land was 1.4 times larger, livestock farming 7 times larger, forest 0.74 times smaller, and built-up area 0.67 times smaller in DJ watershed than in MK watershed. Pollution sources in MK and DJ watersheds were originated at a higher proportion from population including the sewage disposal and a livestock farming area rather than from the land. Water consumption and land use distribution influenced the water quality of the rivers; DJ watershed had far lower value of electric conductivity, $BOD_5$, TN and TP than MK watershed. A large proportion of paddy field also influenced to reduce pollute loadings after rainfall; DJ watershed, which has a relatively large area of paddy fields, had a far lower delivery load after rainfall than MK watershed even though DJ watershed had large livestock farming area. As paddy fields was irrigated by Iksancheon water, 37% of nitrogen, 50% of phosphates and 14.0% of $BOD_5$ was removed by the paddy field just after flowing 150 meter, and rice plants could remove TN 100.0 kg, $P_2O_5$ 24.0 kg, and $K_2O$ 119.2 kg per hectare at harvest by irrigation of Iksancheon water. Conclusively, rice paddy fields played a positive role to conserve the water quality in the Iksancheon watershed.

• Korean Journal of Environmental Biology
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• v.35 no.2
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• pp.105-115
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• 2017

The present study is to understand the Bongseonsa stream in the National Arboretum fish fauna variation through comparison with historical data and to evaluate the stream health situated. We performed investigations over three times from April to September 2015. In the survey, 2,960 individuals which belonging to 22 species, 8 families were collected. Dominant species by number was Zacco platypus and subdominant species was Zacco koreanus. Seven Korean endemic species (Squalidus gracilis majimae, Microphysogobio yaluensis, Zacco koreanus, Koreocobitis rotundicausata, etc) were observed and showed a ratio of 36.4%. The community analysis revealed that the structure of fish community in the study sampling sites was instability in having dominance 0.79 (${\pm}0.15$), diverse 1.21 (${\pm}0.60$), evenness 0.58 (${\pm}0.15$) and species richness 1.49 (${\pm}0.83$). The values in the Qualitative Habitat Evaluation Index (QHEI) was averagely 122.9 (${\pm}44.8$) in the Bongseonsa stream and this was showed to have favorable habitat surroundings. As a result of tolerance guild analysis, the total number of sensitive species and intermediate species were higher than tolerant species. Analysis was divided into A and B two groups of fiducial 12.25% in Cluster analysis degree of similarity between study sampling sites. Fish Assessment Index (FAI) was rated A and B grade in Bongseonsa stream that stream health showed favorable. However Wangsuk stream as a urban stream rated C grade and analysed the lowest grade in the whole study sampling sites. There was high correlation beteween FAI and various indexes, dominance, diverse, evenness and sensitive species and intermediate species.

• Korean Journal of Ecology and Environment
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• v.40 no.1
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• pp.163-172
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• 2007

In this study, fish fauna and stream characteristics were surveyed during October-November 2003 in 31 small streams, which are small sub-tributaries of Geum River. The small streams were classified into 4 types of steep mountainous (SM), mountainous-flatland (MF), flat land (FL), and agricultural watercourse (AW) streams, and their types were categorized by features of stream width, water depth, bottom substrate, riparian vegetation, and landuse patterns. The fishes collected during this survey were identified 4 families and 8 species. Dominant family was Cyprinidae, and the most dominant species was Rhynchocypris oxycephalus with 73% (419 individuals) of the total. Only one species of R. oxycephalus was observed in the all five steep mountainous streams, which was surrounded by 100% forest area and had no point-and non-point pollution sources. The observed frequency of R. oxycephalus (as a relative proportion of species) showed a significant positive correlation (r=0.754, p<0.001, n=31) with the substrate composition of bedrock and boulder, indicating that the species prefer the bedrock and boulder rather than the sand or small pebble. Evidently, all five steep mountainous streams were judged as excellent condition (1st rank) according to the criteria of biological water quality, the Ministry of Environment, Korea. This result was accord with a general tendency of the species in most upper stream of the Koreas streams. One family and one species were found at the steep mountainous types and 4 families 6 species were at the mountainous-flatland. Four families 8 species were found at the flat land, which showed most diverse habitat, and 2 families 2 species were collected agricultural watercourse. These study results of 1st-order streams suggest that R. oxycephalus was considered as one of 1st rank ecological indicator species, and that the dominant area should be protected from various pollutions and disturbances.

• The Korean Journal of Mycology
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• v.46 no.3
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• pp.295-306
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• 2018

In the present study, we compared the effects of 50% ethanolic extracts of Chinese and Korean Wolfiporia cocos (CPE and KPE) on in vitro lipid accumulation in 3T3-L1 cells and their anticancer activities in Sarcoma 180 cells. We further compared the anticancer activities and the 50% inhibitory concentrations ($IC_{50}$) of CPE with KPE with cultivated for one and two years in a landfill and a facility (LPE and FPE), respectively. In addition, the single oral dose toxicities of CPE and KPE were evaluated in mice. Lipid accumulation was inhibited after 48 hours, in CPE and KPE treated 3T3-L1 cells; however, no significant difference was observed between CPE and KPE in their lipid accumulation inhibitory activities. The anticancer activity of KPE was higher than that of CPE at $300{\mu}g/mL$ (p<0.05), revealing the possibility of an auxiliary biological means for origin identification. The anticancer activities of LPE and FPE were significantly stronger than that of CPE (p<0.05) but there was no difference between extracts from one- and two-year-old W. cocos, irrespective of the cultivation method. In single oral dose toxicity tests, CPE and KPE did not induce mortality during the 14-day observation. Thus, the 50% of lethal dose ($LD_{50}$) of CPE and KPE were estimated to be higher than 2,000 mg/kg. Taken together, our results indicate that the anticancer assay could be an auxiliary means of identifying the origin of W. cocos. In addition, artificial cultivation could be an alternative way to reduce the import of W. cocos. Lastly, 50% ethanolic W. cocos extracts could be potential candidates for obesity and cancer managements.

• Journal of the Korean Wood Science and Technology
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• v.46 no.1
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• pp.17-28
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• 2018

In this study, catalytic activation using sulfuric acid lignin (SAL), the condensed solid by-product from saccharification process, with potassium hydroxide at $750^{\circ}C$ for 1 h in order to investigate its potential to nanoporous carbon In this study, catalytic activation using sulfuric acid lignin (SAL), the condensed solid by-product from saccharification process, with potassium hydroxide at $750^{\circ}C$ for 1 h in order to investigate its potential to nanoporous carbon material. Comparison study was also conducted by production of activated carbon from coconut shell (CCNS), Pinus, and Avicel, and each activated carbon was characterized by chemical composition, Raman spectroscopy, SEM analysis, and BET analysis. The amount of solid residue after thermogravimetric analysis of biomass samples at the final temperature of $750^{\circ}C$ was SAL > CCNS > Pinus > Avicel, which was the same as the order of activated carbon yields after catalytic activation. Specifically, SAL-derived activated carbon showed the highest value of carbon content (91.0%) and $I_d/I_g$ peak ratio (4.2), indicating that amorphous large aromatic structure layer was formed with high carbon fixation. In addition, the largest changes was observed in SAL with the maximum BET specific surface area and pore volume of $2341m^2/g$ and $1.270cm^3/g$, respectively. Furthermore, the adsorption test for three kinds of organic pollutants (phenol, 2,4-Dichlorophenoxyacetic acid, and carbofuran) were conducted, and an excellent adsorption capacity more than 90 mg/g for all activated carbon was determined using 100 ppm of the standard solution. Therefore, SAL, a condensed structure, can be used not only as a nanoporous carbon material with high specific surface area but also as a biosorbent applied to a carbon filter for remediation of organic pollutants in future.

• Korean Journal of Plant Resources
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• v.21 no.2
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• pp.117-127
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• 2008

The vascular plants in the Eco-Arboretum site, Mt. Gumwon appeared to be 369 taxa; 84 families, 217 genera, 319 species, 43 varieties and 7 forms. Based on the list of the rare plants, 2 taxa existed in the studied areas; Abies koreana (Preservation priority order; No. 73), Paeonia obovata (No. 97) and based on the list of Korean endemic plants, 12 families, 14 genera, 11 species, 3 varieties, 1 hybrid, 15 taxa existed; Cephalotaxus koreana, Abies koreana (Planted species), Carex okamotoi, Salix hallaisanensis, Salix purpurea var. japonica, Clematis trichotoma, Thalictrum actaefolium, Lespedeza ${\times}$ tomentella, Vicia nipponica, Stewartia koreana, Hypericum attenuatum var. confertissimum, Paulownia coreana (Planted species), Weigela subsessilis, Aster koraiensis (Planted species). Specific plant species by floral region were total 38 taxa; Paeonia obovata in class V , 13 taxa (Lilium leichtlinii var. tigrinum, Betula costata, Betula davurica, Ulmus davidiana, Spiraea frutschiana, Prunus maackii, Syringa reticulata var. mandshurica, Cynanchum inamoenum, Lonicera subhispida, Cacalia firma, etc.) in class III , 5 taxa (Heloniopsis orientalis, Chrysosplenium pilosum, Acer triflorm, Viola tokubuchiana var. takedana, Teucrium veronicoides, etc.) in Class II . 19 taxa (Dryopteris erythrosora, Arisaema ringens, Veratrum versicolor, Polygonatum inflatum, Salix glandulosa, Betula schmidtii, Alnus hirsuta, Quercus variabilis, Aconitum japuense, Dicentra spectabilis, Chrysosplenium flagelliferum, Impatiens noli-tangere, Ilex macropoda, Tilia amurensis, Fraxinus mandshurica, Trigonotis icumae, etc.)in class I . The naturalized plants in this site were 5 families, 13 genera, 15 taxa (Rumex acetocella, Rumex obtusifolius, Trifolium repens, Oenothera odorata, Erigeron annuus, Erigeron philadelphicus, Bidens frondosa, Taraxacum officinale, etc.) and naturalization rate was 4.1% of all 369 taxa vascular plants.

• Geophysics and Geophysical Exploration
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• v.17 no.1
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• pp.1-10
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• 2014

To reveal and classify site characteristics in densely populated areas in Chuncheon, Korea, Rayleigh-waves were recorded at 50 sites including four sites in the forest area using four 1-Hz velocity sensors and 24 4.5-Hz vertical geophones during the period of January 2011 to May 2013. Dispersion curves of the Rayleigh waves obtained by the extended spatial autocorrelation method were inverted to derive shear-wave velocity ($v_s$) models comprising 40 horizontal layers of 1-m thickness. Depths to weathered rocks ($D_b$), shear wave velocities of these basement rocks ($v_s^b$), average velocities of the overburden layer ($\bar{v}_s^s$), and the average velocity to a depth of 30 m ($v_s30$), were then derived from those models. The estimated values of $D_b$, $v_s^b$, $\bar{v}_s^s$, and $v_s30$ for 46 sites at lower altitudes were in the ranges of 5 to 29 m, 404 to 561 m/s, 208 to 375 ms/s, and 226 to 583 m/s, respectively. According to the Korean building code for seismic design, the estimated $v_s30$ indicates that the lower altitude areas in Chuncheon are classified as $S_C$ (very dense soil and soft rock) or $S_D$ (stiff soil). To determine adequate proxies for $v_s30$, we compared the computed values with land cover, lithology, topographic slope, and surface elevation at each of the measurement sites. Due to a weak correlation (r = 0.41) between $v_s30$ and elevation, the best proxy of them, applications of this proxy to Chuncheon of a relatively small area seem to be limited.

• Journal of Life Science
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• v.20 no.9
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• pp.1353-1357
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• 2010

Quantification of the ecosystem respiration is essential in understanding the carbon cycling of natural and disturbed landscapes. Soil respiration and some environmental factors which affect soil respiration were investigated in a Larix leptolepis plantation inKongju, Korea. Soil respiration was measured at midday of the $15^{th}$ and $30^{th}$ day of every month from May to December in a non-cutting area (Control) and a cutting area (Treatment) with IRGA Soil Respiration Analyzer. Throughout the study period, average soil temperature and water content were $23.3{\pm}0.5^{\circ}C$ and $27.76{\pm}7.12%$ for control, and $25.9{\pm}3.1^{\circ}C$ and $24.55{\pm}5.12%$ for treatment, respectively. There was a positive correlation ($R^2$=0.8905) between soil respiration and soil temperature in the study area. However, there was no significant correlation between soil respiration and soil moisture ($R^2$=0.4437). The seasonal soil respiration increased in the summer and decreased in the winter. In August, maximum soil respirations in the control and treatment areas were $0.82{\pm}0.13$ and $1.32{\pm}0.10$ $gCO_2{\cdot}^{-2}{\cdot}r^{-1}$, respectively. Total amounts of $CO_2$ evolution in the control and treatment areas from May to December in 2008 were 2,419.2 and 3,610.8 $CO_2g{\cdot}m^{-2}$, respectively. The amount of soil respiration in the treatment area was 49.3% greater than in the control. Increased soil respiration in the treatment area may be due to increased soil temperature, which drives increased microbial decomposition. According to our present investigation, forest cutting will increase the atmospheric $CO_2$ by increasing soil respiration.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.1
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• pp.44-50
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• 2013

The persons in charge of management request diagnosis and prescription to tree hospitals in order to get consultation about the problems like blight that occur in landscape tree management. This study aims to analyze what the main problems and questions raised by landscape gardeners are and those concerned in landscape tree management. This is done by investigating landscape tree-related questions and answers uploaded on the online consultation boards of the plant diagnostic centers approved in Korea including the Seoul National University Plant Clinic, the Chungbuk National University Plant Hospital, and the Kangwon Diagnostic Center. As a result, those concerned in landscape occupied the most as 81.4% among the questioners. However, only 11.5% did explain the plant management history or surrounding environment, which is essential for landscape tree diagnosis when asking questions. This shows that those concerned in landscape lack basic knowledge or interest about plant diagnosis. Among 263 questions about landscape trees, questions about physiological damage included 94 cases that were the most taking up 35.8%. Moreover, the next were damage by insects and damage by disease in order. It is thought that due to the characteristics of physiological problems that occur by various sorts of stress and with no signs, they tend to request diagnosis or prescription the most. The most frequent reasons for physiological damage are water stress and temperature stress. About damage by disease, there exist many types of diseases, and there are many complex damages accompanied by physiological causes. About damage by insects, the most common include damage by moths. In consideration of this result, universities or technician training centers should provide education for landscape tree management so that landscape technicians and students can acquire essential knowledge and information about landscape tree management and increase their interest in it. In particular, it is necessary to provide profound learning opportunities for plant physiology, and the technicians should make efforts themselves. In addition, it is needed to build organizations to which they can ask technical questions about landscape planting and management in order to understand landscape industry in general and the actual status of landscape planting technique and the actual field. Moreover, to elevate systemicity and expertise in the area of landscape tree management not yet equipped with the foundation, it is needed to cultivate the technicians intensively and conduct research by those concerned both in academic and industrial circles.