• Korean Journal of Ichthyology
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• v.22 no.4
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• pp.238-248
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• 2010

We performed field investigations at six stations in Buk Stream of Goseong-gun, Gangwon-do, Korea, from May to September 2009 to understand the stream's fish fauna and community structure. In the survey, 31 species belonging to 20 families were collected. Dominant species by number was Zacoo koreanus (30.0%), and subdominant species were Pungitius kaibarae (9.4%) and Rhynchocypris steindachneri (9.3%). In biomass, the dominant species was Tribolodon hakonensis (35.5%), and subdominant species were Z. koreanus (22.5%) and Cobitis pacifica (7.5%). Eight Korean endemic fish species and two endangered species (P. kaibarae and Pungitius sinensis) were collected. In addition, four anadromous fish species (T. hakonensis, Oncorhynchus masou masou, O. keta, Gasterosteus aculeatus) and two amphidromus fish species (Plecoglossus altivelis altivelis and Gymnogobius urotaenia) were observed. Interestingly, we verified the existence of several fish species in Buk Stream where they have not lived before. Those species were previously reported to live only in rivers that run into the western and southern sea of Korea. Five of those species (Zacoo koreanus, Z. platypus, Silurus microdorsalis, Liobagrus andersoni and Coreoperca herzi) were reported in Buk Stream in the 1980s. The other species (Pungtungia herzi, Pseudorasbora parva, Squalidus multimaculatus, Misgurnus mizolepis, Koreocobitis rotundicaudata, Silurus asotus and Odontobutis interrupta) have been introduced since the 1990s.

• Journal of Korean Society of Forest Science
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• v.84 no.1
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• pp.31-40
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• 1995

The purpose of this study was to analyze the process of natural plant establishment and revegetation on the slopes of landslide scars, both untreated(l4 plots) and treated plots (14 plots) with rehabilitation measures in 1993 and 1994 at Yongin Hwaseong-gun region. While total of 61 species were identified at surveyed sites. in the region, the pioneer species on landslide scars were Lespedeza cyrtobotrya, Arundinella hirta, Artemisia princeps, Pteridium acquilinum, Erigeron canadensis. Rubus crataegifolius, Stephanandra incisa etc. The species diversity (H') and evenness(E') of the untreated scars were greater than those of the treated scars. Similarity indices in the untreated scars were higher than those in the treated scars, and succession indices showed similar value in both areas. As a conclusion, this study shows that the untreated scars were more influenced by the around-vegetation, and the native vegetations(plants) like Lespedeza cyrtobotrya, Arundinella hirta. Miscanthus sinensis, Artemisia princeps, Pteridium acquilinum, Erigeron canadensis. Rubus crataegifolius, Stephanandra incisa ete. could be more effectively used as plant vegetation for rehabilitation of landslide scars.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.3
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• pp.326-332
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• 2008

This study was conducted to evaluate an early-maturing rice cultivars adaptable to early transplanting cultivation in Yeongnam plain area. High temperature during the ripening stage of paddy rice under the early-transplanting cultivation in Yeongnam plain was to influence in several agronomic traits such as number of spikelet, ripening ratio, grain appearance of milled rice, and yield. 'Gounbyeo' and 'Junghwabyeo' were better than the others in grain appearance of milled rice and ripening ratio, but their yield potential were lower than that of the other varieties. Moreover, 'Gounbyeo' and 'Junghwabyeo' showed high ratio of broken rice. 'Unkwangbyeo' was the highest in yield and eating quality among the tested varieties, but also high percentage of white core and belly in milled rice. Therefore, in order to recommend those cultivars to farmers, it should be needed to establish an optimal cultivation method, such as transplanting density, fertilizer application, and harvesting time, etc. consequently, it should also be required to develop a new varieties with high ripening capability under high temperature condition.

• Journal of Korean Society of Forest Science
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• v.85 no.4
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• pp.571-576
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• 1996

The geological and hydrological survey was carried out in Hyuseok-dong landslide area(10 ha), Youngchoon-myeon, Danyang-gun, Choongcheongbuk-do. The results showed that the bed rocks in this area consisted of shale, sandstone and limestone, and the piles of stones debris were also scattered around the hill above the study area. Soil texture was sandy loam, and bulk density of the soil in the lower part of the area was higher than that of the upper part, but void ratio of the soil in the lower part was lower than that of the upper part. Subsurface water was springing out to the surface in many places in this area. In this area, the storms over 70mm/day were frequent during the summer period from June through September. It was concluded that the occurrence of landslide had a close relationship with the geological characteristics, hydrological conditions and the rainfall distribution.

• Journal of Korean Society of Forest Science
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• v.85 no.4
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• pp.565-570
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• 1996

The landslide survey in an area of about 10 ha was carried out in Hyuseok-dong. Youngchoon-myeon, Danyang-gun, Choongcheongbuk-do. The results showed that there were many indications on geographical changes, such as scars, depressions, upheavals, cracks and destructions of the construction features. The mean degree of slope of the study area was $28^{\circ}$. The results of surface displacement in this area showed that landslide mass is moving in the direction of SE~SEE, and horizontal and vertical movement rate of the center of moving mass was about 1.2m/year and 0.86m/year, respectively. It was estimated that the amount of the soil erosion in the cliff at the lower edge of this area was 0.823m due to the caving erosion by the Namhangang(River) from June through November, 1995.

• Korean Journal of Ichthyology
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• v.28 no.4
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• pp.239-248
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• 2016

The habitat, age and spawning characteristics of the Korean eastern spined loach, Iksookimia yongdokensis, were investigated to obtain baseline data for its ecological characteristics in the Chuksancheon (stream), Yeongdeok-gun, Gyeongsangbuk-do, Korea. The difference between the habitats of juveniles (0+) and 1~4 year old loaches was that juveniles mainly inhabited sandy bottoms (substratum particle size $0.6{\pm}1.44\;cm$) with very slow velocities of water current ($2.4{\pm}2.09\;cm/sec$) and low depths ($29.2{\pm}7.57\;cm$), whereas 1~4 year old loaches inhabited pebble and cobble bottoms (substratum particle size 5.5~6.1 cm) with relatively fast velocities of water current (3.8~4.6 cm/sec) and deep depths (50~70 cm). The age groups for I. yongdokensis (female) estimated by the frequency distribution of total length in the spawning season (July) indicated that the 35~64 mm is 1-year old, the 65~94 mm group is 2-year old, the 95~119 mm is 3-year old, and the 120~145 mm is more than 4-year old. The sex ratio (♂/♀) was 0.69, and females were 10~30 mm larger than males. The lamina circularis at the base of the pectoral fins in males, a secondary sexual characteristic, formed at the 13th month after hatching. The spawning season according to the gonadosomatic index (GSI) was June to July with water temperatures of $20{\sim}25^{\circ}C$. The average number of eggs was $2,292{\pm}618$, with a diameter of $1.46{\pm}0.02\;mm$ for mature eggs.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.319-326
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• 2014

Two bacterial strains, named as LE17 and LE22, were isolated from traditionally fermented soybean products in order to select lactic acid bacteria for the reduction of biogenic amines and harmful bacteria. Both strains were identified as Pediococcus pentosaceus by 16S rRNA sequence analysis and additional biochemical tests. The strain LE17 reduced the amines by 13.7% for histamine and by 25.9% for tyramine, when it grew in minimal synthetic media containing 0.1% (w/v) histamine and 0.1% tyramine at $30^{\circ}C$ for 48 h, while the strain LE22 reduced the amines by 23.7% for histamine and by 15.7% for tyramine. Both strains also had broad inhibition spectra against pathogens. Considering their properties, they could be used as starters for industrial soybean fermentation.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.286-290
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• 2008

Many important traits have been tagged allowing plant breeders to apply marker assisted selection (MAS) in rice. PCR itself is simple to set up, and requires little hands-on time. However, a crucial limiting step of MAS programs is the reliable and efficient extraction of DNA which can be performed on thousands of individuals. In this study, We describe a modification of the DNA extraction method, in which cetyltrimethylammonium bromide (CTAB) is used to extract DNA from leaf tissues for suitable MAS in rice. We followed the standard 2% CTAB extraction method in all the procedure. In addition we used the 1.2 ml 8-strip tube instead of 1.5 ml E-tubes to fit the 8-multichannel pipette and employ the 96 well plate to use the swing bucket centrifuge. Our modified CTAB DNA extraction method offers several advantages with respect to traditional and simple methods. 1) adult leaf samples collected in paddy field are applicable. 2) 96 leaf samples can be homogenized only one-time by using tungsten carbonate bead and 96well block. 3) semiautomatic loading method using 8-multichannel pipette from DNA extraction to electrophoresis of PCR products. 4) our system can extract about 400 leaf samples per day by only one technicion. Therefore, this method could be useful for marker assisted breeding in rice.

• Korean Journal of Ichthyology
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• v.33 no.4
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• pp.278-286
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• 2021

The habitat characteristics and feeding ecology of the Siberian stone loach Barbatula toni were investigated in Bukcheon (Stream), Eocheonri, Ganseong-eup, Goseong-gun, and Gangwon-do, Korea from January to December 2013. B. toni lived in rapids or slow rapids from the upper stream to downstream, with the largest number of inhabitants in the middle-downstream regions. As a result of analyzing habitat preferences by age, 0+ and 1+ to ≥3+ showed differences. Ages of 0+(juveniles) lived mainly in rapidly flowing water (37.6±26.79 cm/sec) and low water depths (13.3±9.47 cm) in the pebble bottoms (substratum particle size 9.5±6.66 cm), but ages 1+ to ≥3+ lived mainly in relatively slowly flowing water (13.3±17.33 cm/sec) and relatively deep depths (25.9±10.31 cm) in stone and large stone bottoms (substratum particle size 18.0±7.63 cm). B. toni was mainly eaten from March to December when the temperature was above 5℃, and the amount of food eaten peaked in June and October. Their main food sources analyzed by the index of relative importance (IRI) included Diptera (57.0%), Ephemeroptera (29.3%), and Trichoptera (13.5%). The juveniles (age 0+) fed on small-sized prey such as Diptera and Trichoptera whales, but as they grew, they mainly ate large-sized Ephemeroptera. These feeding habits and changes in food according to the growth of B. toni were very similar to those of sibling species, B. nuda.