• Tuberculosis and Respiratory Diseases
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• v.62 no.2
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• pp.98-104
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• 2007

Background: Although there is an increasing incidence of Mycobacterium abscessus pulmonary disease in Korea, the optimal therapeutic regimen has not yet been established and there are no reports of the long-term treatment outcomes. This study examined the long-term treatment outcomes of M. abscessus pulmonary disease. Methods: Twenty-nine patients diagnosed with M. abscessus pulmonary according to the American Thoracic Society criteria and treated from January 1996 to December 2003 were enrolled in ghis study. The clinical characteristics, radiological findings, treatment outcome, and follow up data were analyzed retrospectively. Results: The mean age of the 29 patients was 56.1 (${\pm}13.6$) years and there was a female (22/29) dominance. The chest radiography revealed the nodular bronchiectatic type to be dominant (69%, 20/29). Twenty-seven (93.1%) were prescribed clarithromycin-containing regimens, and injectable drugs, mainly aminoglycosides, were included in the regimen of nineteen patients. The most predominant regimen (48.3%) consisted of clarithromycin and amikacin. The treatment success, failure, and default were achieved in 19(65.5%), 9(31.0%), and 1(3.4%), respectively. The median duration to culture conversion was 42 days (range 15-362) and the median duration of treatment in the success group was 543 days (range 176-1,160). An adjunctive surgical resection was performed in five patients, which resulted in treatment success in two patients. After the completion of treatment, nineteen patients were followed up for a median duration of 931 days (range 230-2,294). Only one (5.3%) patient relapsed 45 days after completing treatment. Conclusion: Treatment with clarithromycin-containing regimens resulted in a successful treatment in approximately two thirds of patients with M. abscessus pulmonary disease. The long-term relapse rate was also quite low.

• Korean journal of applied entomology
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• v.30 no.1
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• pp.65-79
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• 1991

In order to investigate the species composition and the colony density of ants in Mt. Namsan, Seoul, 39 quadrats were installed in 13 vegetations, 443 colonies of ants were collected from June, 1989 to October, 1990. As the result, 4 subfamilies, 23 genera, 28 species was confirmed. Among them, Cerapachys humicola $O_{GATA}$ is new to Korean fauna along with the subfamily Cerapachinae. For the species composition of ant communities in each vegetation, Robinia pseudoacacia vegetation(containing 3 subfamilies, 14 genera, 15 species-53.6% of all colonies collected in Mt. Namsan) and Quercus mongolica vegetation (3 subfamiles, 12 genera, 14 species -50%) showed relatively rich composition, while Platunus orientalis vegetation (3 subfamilies, 3 genera, 3 species) showed the simplest composition. Colony density was the highest in Prunus sargentii vegetation (7.875 colony /$m^2$) and the lowest in Platunus orientalis (1.000 colony/$m^2$). The relative density of Paratrechina flavipes proved to be the highest (RD = 0.422) and that of Cerapachys humicola $O_{GATA}$ Massor aciculatus was the lowest (RD = O. 002 respectively). In the analysis of the similarity of ant communities between each vegetation by S¢rensen's coefficient, Prunus sargentii was very similar to Sorbus alnifolia (0.745) and Pinus densiflora (0.736), but had the lowest similarity to Metasequoia glyptostoboides and Chamaecyparis pisifera vegetation (0.164 respectively). Dominance of ants in each vegetation analyzed by Simpson'formula was found to be high in Platunus orientalis ($\lambda$ = 0.393) and Sorbus alnifolia ($\lambda$ = 0.392) and the lowest in Metasequoia glyptostroboides vegetation($\lambda$= 0.067). The analysis of diversity by reverse Simpson's coefficient revealed that it was high in Metasequoia glyptostroboides ($d_s$ = 14.925), Pinus rigida ($d_s$ = 7.874) and was the lowest in Platunus orientalis vegetation ($d_s$ = 2.545). Evenness calculated by using d. and $d_{max}$(maximal diversity) was high in Metasequoia glyptostroboides ($E_s$ = 0.714) and Chamaecyparis pisifera vegetation ($E_s$ = 0.624). On the contrary, Quercus mongo/ica vegetation had the lowest value of evenness ($E_s$ = 0.182).

• Korean Journal of Environment and Ecology
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• v.26 no.1
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• pp.46-56
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• 2012

Benthic macroinvertebrates were investigated in Hoeongseong Lake region from March to October 2010, Korea. Macroinvertebrate communities, composition of the functional feeding groups, habitiat oriented groups and the biological water quality were assessed above and below Hoeongseong Dam in the lake region. Six sites, two (St.1~2) above the lake, two (St. 3~4) into the lake, and two (St. 5~6) below the dam, were selected for quantitative (Surber sampler $30cm{\times}30cm$, mesh size 0.2 mm) and qualitative (Hand net) samplings of benthic macroinvertebrates. As a result, a total of 83 species belonging to 43 families, 17 orders, 8 classes, and 5 phyla were recognized. The EPT-group (50 spp. : 60.24%) that is major taxa or EPT-group plus Diptera (61 spp. : 73.49%) occupied most of benthic macroinvertebrates community. Based on quantitative sampling, the number of benthic maroinvertebrates above the lake was 2,399 individuals including 54 species, 28 families, 11 orders, 4 classes, and 4 phyla, whereas 510 individuals including 16 species, 12 families, 7 orders, 4 classes, and 3 phyla in the lake and 626 individuals including 62 species, 33 families, 13 orders, 6 classes, and 4 phyla below the dam were collected respectively. Dominance index was the highest, with 0.82-0.93 ($0.87{\pm}0.05$) in Hoeongseong lake (St. 3-4), diversity index was 3.04-3.16 ($3.10{\pm}0.06$), evenness index was 0.79-0.85 ($0.82{\pm}0.03$), and richness index was 7.27-8.52 ($7.90{\pm}0.63$), which were relatively higher below the dam sites. In the functional feeding groups, collector-gatherers and collector-filterers were the highest in the whole sites, and predators (Micronecta sedula) was appeared highly in the lake. Moreover, swimmers, burrowers, and clingers were considerably occupied in all collecting sites. The result of the DCA, similarity analysis, and MRPP were well reflective of the composition of lake and stream macroinvertebrates. ESB indicate that the lake sites were evaluated heavily polluted under priority improvement waters. Also, Semisulcospira gottschei, Ecdyonurus kibunensis, Epeorus pellucidus, Rhoenanthus coreanus, Stenelmis sp., and Cheumatopsyche brevilineata are considered as an indicator species above and below Hoeongseong Lake, whereas Macrobrachium nipponense and Micronecta sedula are indicated in the lake.

• Korean Journal of Environment and Ecology
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• v.26 no.4
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• pp.559-575
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• 2012

This study, targeting Namhan Mountain Fortress which was designated as a No. 57 national historic site and placed on the World Heritage Tentative List in 2010, was intended to identify the change of vegetation structures by reviewing past references, pictures, research data and additionally conducting a site survey. Also, it was designed to draw up measures for restoring vegetation suitable for historically and culturally valuable Namhan Mountain Fortress. According to the biotope mapping of study site, Quercus spp. forest distributed a greatest part of area with 40.8% of $2,611,823m^2$. Pinus densiflora forest, highly likely to go through ecological succession, was dispersed in the whole region of Cheongryangsan, the area from West Gate to North Gate and the ranges between South Gate to Cheongryangsan with taking 16.5%. Pinus densiflora forest with a low probability of succession amounted to 4.7% and was dispersed mainly in the forest behind Namhansan elementary school. Pinus densiflora going on the ecological succession is distributed a portion of 2.9%. And the currently dying out Pinus densiflora forest amounted to 2.1%. As a result of analysis of the vegetation structure for 19 years, the succession from Pinus densiflora forest to Pinus densiflora and succession from Quercus spp. mixed forest to Quercus spp. forest to Carpinus laxiflora forest were predicted. Additionally, Quercus spp. expanded its dominance over time. According to the characteristics of each classified zone, the site was categorized into $553,508m^2$ area of Pinus densiflora forest area for the landscape maintenance, $114,293m^2$ area of Pinus densiflora forest area for the landscape restoration, $205,306m^2$ area of Pinus densiflora forest area for the disclimax, and $1,169,973m^2$ area of Pinus densiflora forest area for inducing ecological succession.

• Journal of Ecology and Environment
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• v.29 no.6
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• pp.593-602
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• 2006

Species composition, spatial distribution of major species, diameter and height classes distribution, and species diversity were .analyzed in the Korean red pine (Pinus densiflora, hereafter referred as pine) forest in the permanent quadrats, which were designed for Long Term Ecological Research (LTER). Collected data were compared with those from the other areas including urban center (Mt. Inwang and Hongneung) and boundary areas (Mts. Acha, Bukhan, Bulam, Cheonggye, Daemo, and Surak), and natural areas (Mts. Seolak, Songni, and Wolak) to clarify the ecological characteristics of pine forest on Mt. Nam. Species composition of pine forest on Mt. Nam showed a similarity with those of urban center but did a little and big differences with those on urban boundary and natural areas, respectively. Such differences that pine forest on Mt. Nam showed, were usually due to Styrax japonicus, Sorbus alnifolia, Oplismenus undulatifolius, Ailanthus altissima, Ageratina altissima and so on, which showed higher coverage there. Predicted from diameter and height classes distribution of tree species, pine forest on Mt. Nam showed a possibility to be replaced by a S. japonica. Considered that this replacer species is not only a sub-tree but also shade intolerant, such successional trend could be interpreted as a sort of retrogressive succession. Those on urban boundary and natural areas showed a difference by displaying probabilities to be maintained as themselves as an edaphic climax or succeeded to oak forests. Species diversity of pine forest on Mt. Nam was lower than those in urban boundary and natural areas due to excessive dominance of several species, which led to different species composition from the other areas. Plants, which produced the differences, were species that flourishes in the polluted industrial area (S. japonica and S. alnifolia), favors the disturbed site (O. undulatifolius), and exotic species (A. altissima and Eupatorium rugosum). Those results reflects that pine forest of Mt. Nam was exposed on severe environmental pollution and excessive human interferences.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.1
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• pp.55-66
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• 2018

The cactus habitat in Jeju Island has a phytogeographically specific distribution in the East Asian region, and forms a unique landscape as the only native cactus (Opuntia ficus-indica (L.) Mill.) habitat in Korea. However, there has been no detailed investigation on the distribution of cacti in the habitat and no investigation on the diversity of the mixed composition of plants in the habitats and their correlation with the distribution of cactus populations. This study attempted to investigate the diversity of vascular plants in the Wollyeong-ri cactus habitat and record the actual distribution and trends of cactus distribution. In addition to the distribution characteristics of cacti, we also discuss the characteristics of species reflecting the characteristics of the habitat among the mixed population of plant species, as well as the biological and environmental factors that threaten the maintenance of cactus populations or require management for preservation of cacti. Considering the phenological character, we conducted the field surveys for flora identification six times between June 2015 and September 2017. The Engler classification system was used for the arrangement sequence and names of plants, and the Korean Plant Names Index was adopted for the Korean name of the species. The study results showed that the Wolryung-ri cactus habitat in Jeju Island has the characteristic physiognomy of an area dominated by cactus. For the vascular plants, a total of 125 taxa were identified, including 53 families, 104 genera, 109 species, 15 varieties and 1 forma. Endangered plants specified by the Ministry of Environment were not found. Two species, Cyrtomium falcatum and Asplenium incisum, were identified as the ferns, and no gymnosperms were found. In addition, 123 taxa of angiosperms, 91 taxa of dicotyledones and 32 taxa of monocotyledons were identified. The distributions of cacti were confirmed in 289 meshes corresponding to 59.3% of the total 487 meshes in the cactus protected area, which showed various coverage distributions ranging from 5% to 95%. Most of the meshes where no cacti were found are coastal areas with exposed basalt rocks where the soil depth has not developed or extremely restricted due to repeated waves, or areas where artificial facilities, grasslands, and observation paths have been constructed. On the other hand, there were 71 lattice points in 14.5% of the total area where the cactus showed 70% or higher dominance. Cacti are randomly distributed in these areas. They have adapted to the microhabitat environment and are found to be opportunistically distributed along the growable locations. Considering that the reproduction of cacti in the habitat is mostly dependent on parthenogenesis, the present distribution seems to reflect the potentially distributable regions of cacti in the habitat. Based on the results of field surveys, a management plan for conservation and protection of the protected areas has been proposed.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.304-309
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• 2011

BACKGROUND: Generally, water plants may play an important role in nutrients(N, P) removal in constructed wetlands(CWs). Previous studies considered nutrients uptake by water plants in various CWs for treating point source pollution. On the other hand, few studies considered nutrients uptake by water plants in free water surface(FWS) CWs for treating non-point source pollution. METHODS AND RESULTS: To investigate characteristics of nutrient uptake by water plants in FWS CWs, dry weights, nutrients content and nutrients uptake by water plants were investigated from April, 2008 to October, 2008. Dominance plants were Phragmites japonica STEUD (PHRJA), Nymphaea tetragona ANGUSTA(NTMTE), Typha orientalis PRESL(TYHOR), Phragmites communis TRINIUS(PHRCO) and Zizanis latifolia TURCZ(ZIZLA) in FWS CWs. The dry weights of water plants in August were higher in the order of TYHOR(54.27 g/plant) > PHRJA(44.30 g/plant) ${\geqq}$ PHRCO(39.60 g/plant) ${\geqq}$ ZIZLA(37.80 g/plant) ${\fallingdotseq}$ NTMTE(36.75 g/plant). The T-N and T-P contents by water plants were not significantly differences regardless of cultivation period. The maximum amount of T-N uptake by water plants in August were 773 mg/plant for PHRJA, 625 mg/plant for NTMTE, 1206 mg/plant for TYHOR, 754 mg/plant for PHRCO and 768 mg/plant for ZIZLA. The maximum amounts of T-P uptake by PHRJA, NTMTE, TYHOR, PHRCO and ZIZLA were 397, 177, 411, 261 and 229 mg/plant in August, respectively. CONCLUSION(s): The results of this study suggest that optimum water plant was Typha orientalis PRESL in free water surface constructed wetlands.

• Korean Journal of Weed Science
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• v.18 no.2
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• pp.128-135
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• 1998

The experiment was carried out to obtain basic informations on sod culture using water foxtail in apple orchard at Kyeongbuk Provincial RDA in 1996 to 1997. Period of seedling emergence varied with sowing time and accumulative temperature. Sowing at Nov. 25 required longer than 100 days, while it needed only 8 days when water foxtail was sowed at Sep. 20. In a view of accumulative temperature, sowing at March 15 needed $139^{\circ}C$ but it required about $1,000^{\circ}C$ at August 10. This result showed that the seed of water foxtail has strong summer-dormancy in natural condition. Water foxtail had s-shape growth curve during growing season, and growth rate was the highest from March to May in this period. Plant height increased 2 times and 4 times for dry weight from March 20 to April 20. However, growth was decreased by summer depression after May. Major weeds in apple orchard were horseweed, akino-nogeshi and shepherd's-purse. These species were suppressed by the dominance of water foxtail. Water foxtail as a cover plant could be used for a method of weed control instead of herbicide in apple orchard.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.4
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• pp.214-226
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• 2013

To understand the changing patterns in phytoplankton communities, we conducted 12 surveys along the Nakdong River, its estuary, and adjacent coastal areas between January 2011 and October 2012 (during the period of barrage construction and sediment dredging). Monthly precipitation ranged from 0 to 502 mm during the survey period, and salinity ranged between 0.1 psu and 0.3 psu in the Nakdong River, regardless of the depth, indicating no seawater influence, while salinity showed large seasonal fluctuations in the estuarine and coastal station, ranging from 0.1 psu to 34.8 psu. A total of 402 phytoplankton species were identified, 178 species from the river and 331 species from the estuary and coastal areas. Phytoplankton standing crop increased in 2012 compared to that in 2011, and was found to be highest in the river, followed by the estuary and coastal areas. Among the top 20 species in frequency of occurrence and dominance, Stephanodiscus spp., Aulacoseira granulata, and Aulacoseira granulata var. angustissima and Pseudo-nitzschia spp. were important species along the river-estuary-coastal areas. Diatoms were the major taxonomic group inhabiting the Nakdong river-estuary-coastal areas. A comparison of seasonal dominant phytoplankton species revealed a slight decrease over the years, from 13 species in 2011 to 10 species in 2012. However, no significant difference was found in the diversity of phytoplankton species between the two survey years, although lightly greater diversity was observed in the coastal areas than in the river and estuary. Cluster analysis with community composition data revealed that the community structure varied significantly in 2011 depending on the time of survey, while in 2012, it hardly showed any variation and was simpler. An increase in the phytoplankton standing crop, fewer dominant species, and simpler community structure in 2012 compared to those in 2011 are probably due to the rapid environmental changes along the Nakdong River. To investigate these ecological relationships, it is necessary to conduct further studies focusing on integrated analyses of biocenosis, including phytoplankton with respect to the changes in nutrient distribution, variation of freshwater discharge, and effect area of freshwater in the Nakdong estuary and adjacent coastal areas.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.4
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• pp.195-205
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• 2013

Excessive input of organic matters from fish cage farming has been considered as one of the major factors disturbing benthic ecosystem, especially in semi-enclosed coastal waters. Recently offshore aquaculture in the vicinity of Jeju-do has been introduced to minimize that kind of negative impact. This study was conducted to investigate the ecological impacts of offshore aquaculture on the macrobenthic polychaete communities. A total of ten sampling works were carried out for 28 months, spanning from 10 days after starting giving feed to 3 months after stopping giving feed. During the study period, mean current velocity was quite strong with the range of 50 cm/s to 70 cm/s. TOC of surface sediment was constantly low. Significant changes in polychaete community were detected just three months after starting giving feed, which were the increase of the number of species and density at all stations. Up to 18 months after the start of farming, the amount of feed provided played an important role in the fluctuation of the number of species and density, especially at 0 m and 10 m stations. After reducing the amount of feed provided, dominance of some opportunistic species within 10 m distance from fish cages still lasted to the end of aquaculture. However, opportunistic species disappeared 3 months after the end of farming, which indicated the sign of recovery from the disturbance. From these results, the amount of food input and the period of cultivation were critical factors disturbing polychaete community and ensuing changes in this offshore and oligotrophic waters as well. In addition, study on the changes of polychaete community structure before and after fish farming showed more detailed changes in benthic ecological state than geochemical approach did.