• Korean Journal of Microbiology
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• v.43 no.3
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• pp.201-209
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• 2007

The CFDA (6-carboxyfluorescein diacetate) direct viable count method and plate count (PC) method using conventional nutrient broth (NB) medium and $10^{-2}$ diluted NB (DNB) medium were applied to samples collected from Mt. Yongdoo In Andong, in an effect to determine the number of living bacteria pine mushroom forest soil. The number of living bacteria determined via plate count in NB medium comprised $5{\sim}8%$ of the CFDA direct viable count, and the bacteria in the DNB medium comprised $40{\sim}47%$. This result indicated that viable but nonculturable (VBNC) bacteria existed in the pine mushroom forest soil at a high percentage. The phylogenetic characteristics of the VBNC bacterial populations in the samples of pine mushroom (Tricholoma matsutake) forest soil were analyzed via the direct extraction of DNA and 16S rDNA-ARDRA. The 115 clones from pine mushroom forest soil were clustered into 31 different RFLP phylotypes by ARDRA. Based on the 16S rDNA sequences, the 31 ARDRA clusters were classified into 6 phylogenetic groups: ${\alpha}-,\;{\beta}-,\;{\gamma}-Proteobacteria$, Acidobacteria, Actinobacteria and Firmicutes. Among these bacterial populations, approximately 85% were classified as members of phylum Acidobacteria. The Acidobacteria phylum was shown to exist abundantly in the pine mushroom forest soil.

• Journal of the Korean Society of Food Culture
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• v.16 no.4
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• pp.341-353
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• 2001

This study was conducted to investigate dietary patterns and assimilation of dietary culture of Korean descendants in Yanbian, China compared to Korean. A dietary survey was conducted using one 24-hour recall method from 730 adults over 30 years of age in Yanbian, China and 695 adults over 25 years of age in Kuri, Korea. The average number of food items consumed per day was 14 in Yanbian and 20 in Kuri and there was a significant difference between the two regions(p<0.001). The foods consumed most frequently were rice, salt, the M.S.G. in Yanbian and rice, green onion and garlic in Kuri. The foods consumed most by amount were rice, cucumber, Soju in Yanbian and rice, Kimchi and grape in Kuri. The average number of dishes consumed per day was 6.4 in Yanbian, 9.4 in Kuri and the difference between the two regions was significant(p<0.001). Total number of dishes appeared in the survey was 253 in Yanbian and 494 in Kuri. The dishes consumed most frequently were cooked-rice, beverages, Kimchi, stir-fried eggplant in Yanbian and cooked-rice, Kimchi, coffee, soybean paste stew, in Kuri. The dish groups appeared most frequently were rice, stir-fried foods, vegetables and Kimchi in Yanbian and rice, Kimchi, beverages and fruits in Kuri. Male subjects in Yanbian Consumed alcohol frequently while adults in Kuri consumed coffee more frequently than Yanbian. The major meal patterns were rice+side dish, rice+soup, rice+side dish+Kimchi in Yanbian and rice+soup+side dish+Kimchi, rice+side dish+Kimchi, rice+soup+Kimchi in Kuri. Stir-fried foods, which were consumed 46.6% of all the meals, were dominant side dish in Yanbian, but stir-fried food, seasoned vegetables and grilled food appeared aver 10% in Kuri. There results show that variety of diet of Korean-Chinese in Yanbian was lower than Kuri. Korean-Chinese tend to keep traditional Korean dietary patterns of consuming rice as staple but were adapted to Chinese dietary patterns of consuming stir-fried side dishes. Efforts should be directed toward preserving Korean traditional patterns of dietary culture among Korean-Chinese population.

• Korean Journal of Ecology and Environment
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• v.50 no.3
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• pp.337-354
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• 2017

Cyanobacteria Aphanizomenon population is widely distributed in the world, and well known as harmful algae by producing toxins and off-flavor materials, thus belonging to one of the taxa that became more interested in the field of limnoecology. In this study, the frequency, intensity, and duration of Aphanizomenon occurrence were increased with the abnormal drawdown of water level in the winter in Boryeong Reservoir, and the spatial and temporal characteristics of them are compared with each other in the perspective of hydrometeorology (1998 to 2017) and limnology (2010 to 2017). In Korea, Aphanizomenon flourished mainly in high temperature, and the appearance in the low temperature was rare in total five times. The harmful cyanobacteria Aphanizomenon was observed in the low temperature (December to February) in Boryeong Reservoir from 2014, and then reached a maximum value of $2,160cells\;mL^{-1}$ in January 2017. In addition, the period exceeding $1,000cells\;mL^{-1}$ at this time was more than 3 months. This was simultaneously associated with abnormal water level fluctuation in the low temperature ($<10^{\circ}C$). The large drawdown of water level in the winter season has the potential to promote or amplify the germination and development of harmful algae. Also, subsequent water quality and ecological impacts(e.g., algal toxins and off-flavor substances) need to be considered carefully.

• Ecology and Resilient Infrastructure
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• v.6 no.4
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• pp.227-235
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• 2019

This study monitored Daecheong 1-bo, Daecheong-stream, which carried out the project in 2014, from 2015 to 2016. The technology applied to the stream was evaluated using Periphytic Algae to check contamination indicators and ecological health of the area with an integral river-bed protection using non-toxic materials. The water quality of the monitoring section was confirmed to be above the river environment standard (II), and it was confirmed that the Saproxenic taxa of the river bed protection were higher than the upper and downstream sections. The TDI, which is an index of attachment algae, was shown in the average 51.03 and 52.15 for the pilot project sections in 2015 and 2016, confirming that the index is of the "normal" grade. This is the other sections in the upstream and downstream sections showed higher than "bad", which is thought to have a positive effect on the habitat of the river ecosystem components, especially the microbial population in river bed protection.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.590-598
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• 2015

Despite various control methods for pine wilt disease, the disease has been increasing at an alarming rate every year in Korea. Still there is a lack of research on the problems of the current methods used to curb the disease. One main method to control pine wilt disease is fumigation for eliminating the larva of the pine sawyer beetle (Monochamus alternatus) which is known as the vector insect for pine wilt disease. We surveyed and analyzed the amount of destroyed uninfected trees in the fumigated area by studying 32 survey plots ($100m^2$) in Miryang city. The destroyed trees' crown area was estimated by induced regression between root collar area and crown area of the remaining trees (coniferous tree: $R^2=57.4$, deciduous broad-leaved tree: $R^2=63.8$). According to the analysis results, the infected trees (cut trees) were 18.7% and cut trees which were not infected were 35.5% of the total tree population of the study area on the basis of total crown area. In case of pine trees, 8.4% of uninfected trees were cut off but 62% of uninfected deciduous broad-leaved trees including Quercus spp. were affected and damaged during the fumigation process. Since these broad-leaved trees dominate the sub-canopy layer of the forest, this indiscriminate interruption of broad-leaved trees has the adverse effect of depriving the public benefits such as shadow, a cooler weather, controlling humidity, etc.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.552-563
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• 2015

The characteristics of ichthyofauna and fish community in Lake Goesan were examined from April 2010 to October 2012. During the survey period thirty six species belonging to 11 families were collected. Dominant species by number were Hemibarbus labeo (29.9%) and Zacco platypus (20.0%). In biomass, the dominant species were H. labeo (37.2%) and Carassius auratus (17.9%). Also, fourteen Korean endemic fish species (38.9%) and one endangered species (Acheilognathus signifer) were collected. Further, one catadromous species was observed for stock enhancement (Anguilla japonica), in addition to two land-locked anadromous species (Hypomesus nipponensis, Plecoglossus altivelis) and three exotic species (Cyprinus carpio (Israeli type), C. cuvieri, Micropterus salmoides). According to the length-weight relation of C. auratus and M. salmoides, the b values were 3.13~2.99, 3.11~2.99, showing a declining tendency annually. However, for H. labeo and Z. platypus, the b values were 2.98~3.07, 3.06~3.23 respectively, showing an increasing trend. The slope values for C. auratus and M. salmoides population conditions were controlled by K factor showing a tendency to decrease, but H. labeo and Z. platypus were showing a tendency to gradually increase.

• Korean Journal of Environment and Ecology
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• v.23 no.1
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• pp.50-55
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• 2009

To understand the status of the migrating Oriental Honey Buzzard(Pernis ptilorhynchus) in Korea, we carried out a preliminary study on the number and local movements of the Honey Buzzard from September 2005 to October 2007 at Hongdo Island, Jeonnam Province, Korea. A total of 702 Honey Buzzards in 2005, 404 individuals in 2006, and 659 individuals in 2007 were recorded during the fall migration season, but during the spring migration season only two and eight birds were observed in 2006 and 2007 respectively. The migrating Honey Buzzard showed peak numbers from 20 September to 5 October at the study site. According to observation of arrival time of538 Honey Buzzard in October 2007, a total of 2l6 birds(40.l %) were passing over Hongdo Island between 7:00 AM to 8:00 AM, rising skyward on columns of warm air. This suggests the use of thermal currents and avoidance of nocturnal movement for crossing water. They preferred moderate winds(<5 m/s in speed) from northwest, but the migrating number apparently decreased in case of strong winds (${\geqq}5 m/s$). This suggests that wind speed and direction are important environmental factors for migration of the Oriental Honey Buzzard. At present, it is unclear which breeding population(from north-eastern China or Japan) passes over Hongdo Island. Moreover, it is difficult to prove migration route and to understand migratory behaviors of the Oriental Honey Buzzard in Korea. To prove the breeding sites and routes of the migrants over the study site, we need more detailed and further studies such as satellite tracking researches.

• Korean Journal of Environment and Ecology
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• v.32 no.2
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• pp.215-224
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• 2018

The climate change is expected to weaken the habitat of Pinus densiflora and P. thunbergii, but they are still in high demand for planting. This study aims to suggest the rational community planting design based on natural forests' community structure in the southeastern region of Korea (warm temperate zone). For this study, we surveyed 22 plots of Pinus densiflora community and 60 plots of P. thunbergii community in Busan Metropolitan City which is located in the southeastern part of the Korean peninsula. We investigated the diameter of breath hight (DBH) and population of each tree layer in a $100m^2$ quadrat and used a regression analysis to derive a regression equation for estimating the mean number of planting individuals in each DBH. The coefficient between canopy layer's DBH and growth individuals per unit area ($100m^2$) was 0.700 for P. thunbergii communities and 0.533 for P. densiflora communities, indicating very high explanatory power by single factor. The predicted regression equation of between DBH and growth density was $Y=31.176e^{-0.055x}$ (X=DBH, Υ=growth individuals per $100m^2$) for P. thunbergii communities and $Y=38.351e^{-0.059x}$ for P. densiflora communities. Planting densities of P. densiflora communities and P. thunbergii communities in southeast region were higher than the central region.

• Korean Journal of Environment and Ecology
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• v.31 no.5
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• pp.472-478
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• 2017

The feeding habits of Coreoperca herzi were investigated from specimens collected in the Geum River, from March to December 2016. The specimens were separated into groups of 38~70 mm, 71~109 mm, and over 110 mm in total length. The live foods of C. herzi included Ephemeroptera, Odonata, Plecoptera, Coleoptera, Diptera, Trichoptera, and fishes. The Korean aucha perches fed mostly on aquatic insects which took up 98.8% of food regarding the number, 55.8% regarding the biomass, and 97.1% in terms of iregarding the index of relative importance. They were carnivorous in diet and predators (stalker) in food intake characteristics and forms when applying Keenleyside's classification. The main food sources of C. herzi were Ephemeroptera, Diptera, and Trichoptera while Odonata, Plecoptera, Coleoptera, and fishes were rare. A food migration was observed since less Ephemeroptera was found and more Trichoptera and fishes were found in the biomass of the feed consumed by larger species. The amount of Coleoptera and Diptera did not change much with the size of the species. The overall composition of live food was not seasonal. The result of the study indicates that, when restoring the streams to be the habitat for the natural population increase of Coreoperca herzi, the environment should be inhabitable to Ephemeroptera, Diptera, and Trichoptera which are the main foods.

• Journal of Wetlands Research
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• v.16 no.1
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• pp.11-18
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• 2014

The effect of elevated $CO_2$ and temperature on ecological characteristics of Cicuta virosa L., the endangered plant were examined under ambient $CO_2$+ambient temperature(AC-AT), ambient $CO_2$+elevated temperature(AC-ET) and elevated $CO_2$+elevated temperature for two years. Shoot length and the number of umbels were not different in three environmental gradients. The number of tillers was high in the order of EC-ET, AC-ET and AC-AT. The number of compound umbel was the lowest in the EC-ET. Fruit set rate was the highest in the AC-AT. These results mean that unsexual propagation of C. virosa may increase by promoting growth of tillers, rather than seed production under future global warming. This population growth study will be used as the important data for the research of Korean endangered species.