• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.270-277
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• 2023

Since its introduction in 1973, the bass, Micropterus salmoides, has spread to dams and rivers in Korea, adversely affecting native fish communities. In this study, after complete removal of bass from Bukchosan Reservoir, an farm reservoir that has lost its function, an attempt was made to indirectly confirm the adverse effects of bass on fish by comparing fish communities in reservoirs of a similar size where bass inhabit. The study was conducted three times a year from 2019 to 2022. As a result of the study, in Bukchosan Reservoir, where the species composition of fish was judged to be simplified due to the habitat of bass, only four species such as Carassius auratus and Rhinogobius brunneus that could be used as a food source for bass appeared before the removal of bass, but after the removal of bass. The appearance and increase of the population of the introduced small freshwater fish (Oryzias sinensis, Rhinogobius giurinus) were confirmed. When comparing Gangjeong Reservoir, Susim Reservoir, which are other reservoirs inhabited by bass investigated in this study, and Bukchosan Reservoir, this result is judged to show a trend of stabilization and recovery of fish species after removal of bass in small reservoirs with high predation pressure of bass.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.535-542
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• 2012

This study was carried out from 2011 to 2012 in order to analyze the cultivation technology system by six organic rice cultivation types in the southern provinces for the purpose of utilizing organic rice farming guidelines. This surveys were conducted by site visit on 8 counties and 115 farms in southern area. Cultivation technology system by six organic rice cultivation types were cultivated by the principle of minimum input or non-input. cropping systems, a mixture of barley and rice, or rice green manure crops were grown. Cultivars were mixture of the local cultivars and Japanese varieties. Soil were managed by a self-manufactured compost, indigenous microorganisms and barley straw without any fertilization. Pest control was mainly practied by purchased eco-friendly organic materials or herbal medication residue and indigenous microbial self-manufactured. Weed was controled by snails and barley straw. In addition, considering the restore of a longtail pitching shrimp and grasshoppers, the fuction of environmental ecology of six organic rice cultivation type proved to be excellent all. Meanwhile, the productivity of the organic farming per 10a were the order of Life and environment > Natural circulation > Stevia > Ji jang > Art and nature > Taepyoung of Farming Methods, but the farmers received prices showed the opposite tendency. Simple profitablity did not show a big difference. But, the productivity of all type of the organic farming were lower then the conventional farming. Finally, If we want to conduct safety and easy farming, we can suggest stevia farming, Natural circulation farming and life and environmental farming out of 6 organic rice cultivation types.

• Journal of Animal Science and Technology
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• v.55 no.3
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• pp.185-194
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• 2013

Microsatellite markers have been a useful genetic tool in determining diversity, relationships and individual discrimination studies of livestock. The level of genetic diversity, relationships among two Korean indigenous chicken brand populations (Woorimatdag: WR, Hanhyup3: HH) as well as two pure populations (White Leghorn: WL, Rhode Island Red: RIR) were analyzed, based on 26 MS markers. A total of 191 distinct alleles were observed across the four chicken populations, and 47 (24.6%) of these alleles were unique to only one population. The mean $H_{Exp}$ and PIC were estimated as 0.667 and 0.630. Nei's $D_A$ genetic distance and factorial correspondence analysis (FCA) showed that the four populations represented four distinct groups. However, the genetic distance between each Korean indigenous chicken brand (WR, HH) and the pure population (WL, RIR) were threefold that among the WR and HH. For the STRUCTURE analyses, the most appropriate number of clusters for modeling the data was determined to be three. The expected probabilities of identity among genotypes of random individuals (PI) were calculated as $1.17{\times}10^{-49}$ (All 26 markers) and $1.14{\times}10^{-15}$, $7.33{\times}10^{-20}$ (9, 12 with the highest PI value, respectively). The results indicated that the brand chicken breed traceability system employing the own highest PI value 9 to 12 markers, and might be applicable to individual identification of Korean indigenous chicken brand.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.2287-2300
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• 2015

This study examined the spatio-temporal distributions of the phytoplankton community in the coastal waters of Gogunsan Islands (CoWGIs), West Sea of Korea, from January to September 2011. A total of 104 species of phytoplankton belonging to 56 genera were identified. This was low compared to the surrounding seas of the West Sea. In particular, diatoms and dinoflagellates comprised 60.5% and 34.6%, respectively, and it was most diverse in autumn. The standing crops fluctuated from $9.6{\times}10^4cells/L$ to $1.0{\times}10^7cells/L$. This was high in winter and summer and low in spring and autumn. The seasonal dominant species were Skeletonema costatum-like species, Thalassiosira nordenskioeldii, Dactyliosolen fragillisimus, and Chaetoceros debilis in winter, Guinardia delicatula in spring, Eucampia zodiacus, Cylindrotheca closterium, Ch. debilis, and Ch. curvisetus in summer, and S. costatum-like species, Ch. debilis, Ch. curvisetus, G. delicatula, and Leptocylindrus danicus in autumn. The total number of autochthonous and tychopelagic species was 39 species. This showed a 1/3 (33.3%) decrease compared to the 1980's. The chlorophyll a concentration fluctuated from $3.82{\mu}g/L$ in autumn to $13.36{\mu}g/L$ in summer. The bio-oceanographic characteristics of the CoWGIs based on principle component analysis (PCA) showed that it was dominated by the Saemangeum water mass in the high temperature season and by the Geum River water mass in the low temperature season. In other words, there has been a conversion to a closed inner bay followed by the dramatic progress of eutrophication, even in the CoWGIs after completion of the Saemangeum embankment.

• Journal of Wetlands Research
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• v.25 no.4
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• pp.335-344
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• 2023

Brachydiplax chalybea flavovittata, a climate-sensitive biological indicator species, was first observed and recorded at Jeju Island in Korea in 2010. Overwintering was recently confirmed in the Yeongsan River area. This study was aimed to predict the potential distribution patterns for the larvae of B. chalybea flavovittata and to understand its ecological characteristics as well as changes of population under global climate change circumstances. Data was collected both from the Global Biodiversity Information Facility (GBIF) and by field surveys from May 2019 to May 2023. We used for the distribution model among downloaded 19 variables from the WorldClim database. MaxEnt model was adopted for the prediction of potential and future distribution for B. chalybea flavovittata. Larval distribution ranged within a region delimited by northern latitude from Jeju-si, Jeju Special Self-Governing Province (33.318096°) to Yeoju-si, Gyeonggi-do (37.366734°) and eastern longitude from Jindo-gun, Jeollanam-do (126.054925°) to Yangsan-si, Gyeongsangnam-do (129.016472°). M type (permanent rivers, streams and creeks) wetlands were the most common habitat based on the Ramsar's wetland classification system, followed by Tp type (permanent freshwater marshes and pools) (45.8%) and F type (estuarine waters) (4.2%). MaxEnt model presented that potential distribution with high inhabiting probability included Ulsan and Daegu Metropolitan City in addition to the currently discovered habitats. Applying to the future scenarios by Intergovernmental Panel on Climate Change (IPCC), it was predicted that the possible distribution area would expand in the 2050s and 2090s, covering the southern and western coastal regions, the southern Daegu metropolitan area and the eastern coastal regions in the near future. This study suggests that B. chalybea flavovittata can be used as an effective indicator species for climate changes with a monitoring of their distribution ranges. Our findings will also help to provide basic information on the conservation and management of co-existing native species.

• Journal of Korean Historical Folklife
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• no.46
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• pp.195-237
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• 2014

Palsapum are ornaments to reveal the purpose of commander of three naval forces as well as symbols to remember the greatness of admiral Yi, Sun-Shin. In 1966, ther were designated as a treasure No. 440 based on their value; however, they have not received attention from academia because they are relics from China. This study compares and analyzes the document, paintings, and relevant references from Korea and China focusing on Palsapum, understands their formal characteristics, and examines their historical value such as years and location of creation. As a result, the study determines five of them are original, but three of them were newly created by the later generations. The five, Dodogin (都督印, Commander's seal)·Yeongpae (令牌, Commander's tablet)·Gwido (鬼刀, Replica of the devil sword)·Chamdo (斬刀, Replica of the decapitation swor d)·and Gognapal (bugle) were created by Ming Dynasty before 1598, and delivered by the hands of General Chen Lin. The other three, Dokjeongi (督戰 旗, Battle flag)·Hongsoryeonggi (紅小令旗, Commander's flag)·and Namsoryeonggi (藍小令旗, Commander's flag), were created in 19th century by Joseon Dynasty. After analysis on the former relics, the study determines that they are not official relics with the dignity of Ming Dynasty but personal relics with regional characteristics; in other words, Palsamun are not the royal gifts from Emperor Shenzong to Admiral Yi, Sun-Shin. but personal momentoes left by General Chen Lin in the Tongjeyoung to celebrate the admiral. The names, variety, numbers, and appurtenances of Palsapum have been changed with time as follows. First, the scholars of Jeseon in 17the century only focused on Dodogin. It was certainly created in Ming Dynasty; however, it was a personal stamp, so considered to be not from the emperor but from General Chen Lin. Second, Palsapum was called Palsamul and consisted of 14 pieces of 8 kinds in 18the century, ; it is confirmed on the 「Dosul(圖說, stories with pictures of」 『Yi Chungmugong Literary Collection』 The sizes of five relics including Dodogin are similar to the records, but their patterns and shapes are exotic, or cannot be found in Joseon. Thus, they reflect the regional characteristics of Guangdong province. Third, they were called Palsapum, and consisted on 15 pieces of 8 kinds in 19th century; it is confirmed on , a sixteen-fold folding screen drawn by Shin, Gwan-Ho in 1861. The stamp box, tablet bag, and three flags were newly created to engrave Joseon style letters and patterns on damageable materials such as leather and cloth. The relics easy to be destroyed have been renewed even after 19th century. Last, there are many misunderstandings about Palsapum by governmental indifference and improper management of records even though they were designated as a treasure in very early times. Thus, authorities should be concerned with Palsapum to provide the measures for stable maintenance of the relics; this will let people remember not only the history of cooperation between Korea and China to stop the Japanese ambition, but also Admiral Yi, Sun-Shin and General Chen Lin to bring victory in Japanese invasions of Korea.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.62-67
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• 1999

As a basic experiment to enhance the symbiotic utility of atmospheric nitrogen on soybean, host affinities and serological distribution of Bradyrhizobium japonicum indigenous to five Korean upland soils were measured. Based on nodulation, the symbiotic affinities between indigenous B, japonicum and eight soybean cultivars were remarkably different among soil inocula. On the whole, the averaged affinities of B. japonicum populations to soybeans were favorable in order of Goseong > Milyang > Suweon soils, but those in Iksan and Namjeju soils were not, especially for Danweonkong, Jangkyeongkong, and Eunhakong soybean cultivars. Regression analyses between nodules mass and shoot dry weight of soybean yielded model with $R^2=0.51$ for Goseong, $R^2=0.45$ for Milyang, $R^2=0.38$ for Iksan, $R^2=0.28$ for Namjeju, and $R^2=0.24$ for Suweon soils. B. japonicum from sampled soils were serologically fell into more than seven serogroups such as YCK 117(34.1%), YCK 141(6.5%), YCK 321(6.5%), YCK 445(4.7%), YCK 338(2.9%), YCK 150(1.2%), YCK 258(0.6%). The dominant serogroup YCK 117 was distributed 51.9 for Namjeju, 45.8 for Goseong, 41.7 for Iksan. 34.2 for Sueveon, and 11.1% for Milyang soils.

• Microbiology and Biotechnology Letters
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• v.27 no.6
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• pp.427-432
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• 1999

For the development of a multifunctional biocontrol agent, the siderophore-producing strain GL7 was isolated from a rhizosphere on chrome azurol S agar. The GL7 was identified as a strain of Pseudomonas fluorescents on the basis of their reactions to standard physicochemcial tests from Bergey's manual, API diagnostic test, and fatty acid analysis. P. fluorescents GL7 considerably inhibited spore germination and hyphal growth of phytopathogenic fungus Funsarium solani in a dual culture. In pot trials of bean with P. fluorescens GL7, the disease incidence was significantly reduced down to 5% from 70% of incidence in the untreated control. P. fluorescens GL7 also enhanced plant growth to nearly 1.5 times than that of the untreated control, promoting elongation and development of the roots. These results suggest that the plant growth-promoting P. fluorescens GL7 can play an important role in the biological control of soil-borne plant disease in a rhizosphere.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.4
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• pp.293-301
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• 1991

Spores of the family Clomaceae, Acaulosporaceae. and Gigasporaceae in the ord er Clomales. isolated from greenhouse soils grown horticultural crop in the southern region of Korea, included those of the following species : Acaulospora biretculata Rothwell & Trappe, A. appendiculata Spain, Sievering & Schenck, A. foveata Trappe & Janos, A. denticulata Sievering and Toro. A. elegans Trappe & Gerd., A. rehmii Sieverding & Toro in Acaulospora species, Gigaspora gigantea (Nicol. & Gerd.) Cerd. & Trappe, G. decipiens Hall & Abbott in Gigaspora species, Glomus ambisporum Schenck & Smith, G. hoi Berch & Trappe, G. caledoniwn (Nicol. & Gerd.) Trappe & Gerd. in Glomus species, Scutellispora aurigloba (Hall) Walker & Sanders, S. calospora (Nicol. & Gerd.) Walker & Sanders, S. coralloidea (Trappe, Gerd. & Ho) Walker & Sanders in Scutellispora species. Sporocarps of Sclerocystis pachycaulis Wu & Chen were also found.

• Parasites, Hosts and Diseases
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• v.36 no.2
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• pp.81-90
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• 1998

The present study was performed to observe the infection status of several kind of animals with indigenous Gnnthostomn in Korea, and morphological characteristics of gnathostome larvae detected from pit-viper, Askistronon breuiccudus, for the species bullfrogs. several kinds of snakes, j.e., 55 Elnphe rufodorsata, 2 Dinodon rufozonatum rufzonatum. 62 Rhnbdophis tisrinus tigrinus and 87 Askistronon app., and 438 cats were examined. A total of 21 larval gnathostomes was detected from 12 pit-vipers, A. breuicnudus. They were 2.233 x 0.343 mm in average size and covered with about 210 transverse rows of minute cuticular spines. Their characteristic head bulbs were provided with 4 rows of hooklets of which average numbers in each row were 36.8, 39.0, 41.7 and 44.3. posteriorly. In the cross sections of midgut level, the intestinal wall consisted of a single layer of 19-25 elongate epithelial cells with a single nucleus. SEM observation of the larvae revealed unique features of head bulb , cuticular spines on transverse striations and a cervical papilla. On the basis of above morphological characteristics, they were identified as the advanced third-stage larvae of Gnothostomo hispinum. It was first confirmed that the pit-viper. ABkistronon breuicaunus is the snake intermediate host of G. hispidun.