• Korean Journal of Environmental Biology
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• v.23 no.3 s.59
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• pp.293-303
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• 2005

Japanese medaka, Oryzias latipes is widely distributed in the North East Asia including Korea, Japan and east China, and commonly used for freshwater toxicity tests and cytotoxicological studies worldwide. In this study, a series of experiments were conducted to identify the potential of the fish as a standard test species for saltwater toxicity evaluation such as marine receiving waters, ocean-dumped materials and sediment pore waters etc. Hatching, growth and mortality rates of the fish were estimated with the wide ranges of salinity from freshwater to seawater (35 psu). Direct exposure of the fertilized eggs in freshwater to the wide ranges of salinity (from 0 to 35 psu) without pre- acclimation to the saltwater revealed no significant differences in hatching rates by salinities (p =0.24). On the other hand, medaka larvae hatched in freshwater and exposed to saltwater directly showed high mortality at > 25 psu treatment groups (p < 0.0001). However, there was no significant difference in mortality of medaka larvae hatched in 13.8 and 14.2 psu at the wide ranges of salinities ($0\~35$ psu). Growth rates of medaka larvae hatched in the above two salinities showed no differences in body length either from 0 to 35 psu treatment groups (p =0.64 for 13.8 psu group and p=0.32 for 14.2 psu group). The number of gill chloride cell in medaka larvae sharply increased when the larvae were exposed to high salinity. Reference tests with zinc chloride revealed 96h $LC_{50}=8.84(7.19\~10.87)mg\;L^{-1}$ using 7~10 day old medaka larvae. These were comparable or better sensitivity in comparison with the other standard test species such as North American sheepshead minnow Cyprinodon variegatus. Based on the results of these experiments, hatching rates and larvalmortality of medaka must be good toxicity parameters for seawater bioassay and the species seems to be a good standard species for both the freshwater and seawater toxicity test.

• Korean Journal of Plant Resources
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• v.23 no.1
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• pp.60-78
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• 2010

To clarify the distribution of vascular plants and their usefulness in Heoninlleung, Ecological Landscape Conservation Areas of Seoul, we investigated it from April, 2006 to June, 2009. Total 313 taxa; 68 families, 191 genera, 264 species, 41 varieties and 8 forma were distributed in Heoninlleung. Among them, 37 taxa were highly abundant everywhere (3A), 16 taxa were highly abundant locally (3B), 70 taxa were moderately abundant everywhere (2A), 96 taxa were common in certain regions locally (2B), 9 taxa were rare but observed everywhere with low frequency (2A) and 85 taxa were rare and observed locally (1B). The economic plants were 293 taxa. There were 156 taxa of edible source, 223 taxa of medicinal source, 141 taxa of ornamental source, 69 taxa of pastoral source, 12 taxa of industrial, and 8 taxa of timber source. Twelve Korean endemic plants were collected. Based on the list of rare plants by the Korea National Arboretum and Ministry of Environment, 2 rare species were found. The specific species of I~V grades by phytogeography were 19 taxa. And twentyfour taxa of naturalized plant species were distributed. Naturalization Index was 7.7% and Urbanization Index was 8.4% in the investigated area.

• Korean Journal of Environment and Ecology
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• v.33 no.2
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• pp.216-227
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• 2019

The purpose of this study is to propose the rational mountain stream management strategy considering the natural conditions and social needs of the Republic of Korea. We reviewed domestic and overseas studies related to mountain streams, identified the study areas by text mining and co-word analysis using the VOSviewer program, and then analyzed the spatial and temporal study trends and topics of each study area. The results showed that domestic studies on mountain streams are still in an initial stage compared to overseas studies. Overseas studies on mountain streams can be classified into four groups: (i) habitat and species composition of fish and invertebrates, (ii) hydrological phenomena and nutrient migration, (iii) transport of sediment and organic materials and the relevant morphological changes by runoff flows, and (iv) plant species composition in mountain streams. Of these study subjects, domestic studies belonging to the (i) group mainly focused on macroinvertebrates while domestic studies belonging to the (iii) group regarded transport of sediment and organic materials as not the ecological disturbance but the source of sediment-related disasters. We then analyzed the rate of each research group to all papers by period and country. The results showed that the overseas studies belonging to (iii) and (iv) groups have increased with time, and the increase was mostly due to the studies in the United States, Brazil, Canada, and China. On the other hand, domestic studies belonging to (i) and (iii) groups increased somewhat with time, but there was a slight lack of correlation between the two subjects. Therefore, the hybridity studies to complement the shortage is necessary for the future.

• Journal of Korean Society of Forest Science
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• v.107 no.4
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• pp.361-377
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• 2018

The aim of this study was to examine whether the guideline by the Ministry of Environment (ME) successfully and appropriately applied the IUCN Red List criteria at regional level and the rare and endangered national list considered eligible. A certain number of vascular plants, which are widely distributed in the world or in east Asia, deemed to be ineligible for assessment at a regional level as Not Applicable category (NA), because it occurs at very low numbers in South Korea. Among 377 vascular plant taxa evaluated by the ME, NA included 238 species, which represented 63.1%. The number of synonymized species or illegitimate name species were 13 species, which accounted for 3.4%. 21 species (9.3%) were threatened at global level and 103 species were possibly candidates species list for Red List assessments at regional level in the near future. The proportion of NA or waiting list was 66.6% among the list assessed by the ME. The most common errors involved incorrectly application of species extinction in case of population extinction in South Korea to the assessment and provided incorrect interpretation of the Red List criteria at regional level. The most assessments proposed by ME were not backed up without quantitative data quality, justifications, and sources. It is suggested that the risk of extinction should be reassessed at least in the Korean peninsula within the light of their overall distribution including far eastern Russia and North eastern China in north and for Japan and Taiwan in south for regional assessment. The results obtained here using the IUCN criteria at regional level showed that the list proposed by the ME produced an overestimation of the number of threatened vascular plants. Also, the misapplication of the term 'species extinction' for regional assessment was open to some degree of subjectivity and misinterpretation.

• Sim-seong Yeon-gu
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• v.30 no.2
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• pp.145-186
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• 2015

This thesis discusses and analyzes Jeju island's shamanistic myth "Samgong Bonpoori" from the perspective of analytical psychology. Similar to the "I live on my fortune"-type folktales discovered in the Korean mainland, "Samgong Bonpoori" is such a widespread myth that similar folktales are found not only in East Asian regions, including Korea, Japan, and China, but also in Ireland. The essence of the story is as follows; One day, a father asked his three daughters whose fortune they lived on. The first two daughters claimed that they owe their lives to their parents. However, the youngest daughter, Gameunjang-agi, replied, against his expectation, that "I live on my own fortune," and showed her fortune and virtue were physically embodied in the line drawn from her genitals to navel. Her answer enrages his father so fiercely that she was expelled and forced to embark on a journey with no one but a black cow carrying food to accompany her. In retaliation for telling lies against her, Gameunjang-agi transformed her two sisters into a centipede and a mushroom, while her parents were turned into beggars afflicted with blindness. Afterward, Gameunjang-agi wandered around the country and eventually found love with a Chinese yam digger. Not long after, they got married, and as a couple, they stumbled upon roots of gold in fields, which brought them an incredible amount of wealth. After this miracle has happened, Gameunjang-agi began to wonder about the status of her parents and decided to organize a party for all the beggars and the blinds in the country. She eventually found her parents and got a chance to reconcile with her sisters. The story ends with her parents regaining their eyesight and Gameunjang-agi reestablishing herself as the "Goddess of Providence." "Samgong Bonpoori" is a myth about a God. A God is ontologically a supremely perfect being; however, in this thesis, it will be discussed as a part of a folktale. Gameunjang-agi can be seen as the anima archetype of the father, which reveals the process of a paternal consciousness being transformed over time. At first, her parents deny Gameunjang-agi. However, after years of suffering from blindness, they regain their eyesight and finally recognize their daughter. This signifies that Gameunjang-agi is a being that has come into the world for a certain "purpose." Gameunjang-agi embodies the creative function of "femininity" that can renew the existing collective consciousness embedded in the patriarchal system. Such recognition of femininity matters to men to a great degree as well as to women. Without knowing their true nature (femininity), the two sisters submit themselves to their parents and conventional values. Not until they suffer from being transformed and captured into small and insignificant beings, a centipede and a mushroom, which symbolize their shadow, they fail to develop their self-awareness. Meanwhile, by reconciling with her parents and sisters--playing a significant role in reuniting the family--Gameunjang-agi turns out to be a figure that can reveal what it truly means to have self-awareness and achieve Self-realization. In conclusion, this story illustrates that recognition of femininity matters to men to a great degree as well as to women, and women's Self-realization plays a critical role in revitalizing the collective consciousness embedded in the patriarchal system.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.2
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• pp.72-85
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• 2010

Seasonal variation in species composition of estuarine fauna in the Han River estuary was determined using monthly samples collected near Ganghwa Island by a bag net from February to December 2009. Total number of species was 86: 54 species of fishes, 16 species of shrimps of crustacean, 12 species of other crustacean such as craps and so on, 3 species of cephalopods and 1 species of jellyfish. Of a total of 86 species, Palaeman carinicauda (32.6%), Acetes japonicus (15.9%), Palaemon gravieri (9.9%), Portunus trituberculatus (7.7%) and Acetes chinensis (6.9%) were predominated in abundance. These 5 crustacean accounted for 73% of total. Abundance, biomass and diversity of Han River estuarine fauna were high in spring and autumn, indicating typical pattern of temperate area. Out of dominant species, the brackish residence species such as Coilia nasus, Chelon haematocheilus, Mugil cephalus, Synechogobius hasta, Lophiogobius ocellicauda, Tridentiger barbatus, Palaeman carinicauda, Palaemon gravieri were collected almost year-round and predominated in abundance. Coastal migratory fauna species such as Coilia mystus, Thryssa hamiltonii, Thryssa adelae, Sardinella zunasi, Engraulis japonicus, Portunus trituberculatus, Acetes japonicus, Collichthys lucidus, Pampus argenteus were most plentiful from spring through autumn. Their adult coastal migratory entered the estuary in spring and large numbers of their juveniles were grew in summer and autumn until moving out to deeper waters for over-wintering, indicating they use estuary as nursing ground. Diadromous fish such as Anguila japonica adults were collected in autumn during their downstream migration. Brackish fauna and crustacean, especially shrimps were predominant, and few contaminant indicator species collected in the Han River estuary, indicating this area maintains the characteristics of natural estuary ecosystem.

• Journal of Plant Biotechnology
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• v.45 no.3
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• pp.171-182
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• 2018

Papaya (Carica papaya L.) is one of the crops widely planted in tropical and subtropical areas. The papaya fruit has low calories and are plentiful in vitamins A and C and in minerals. A major problem in papaya production is a plant disease caused by the papaya ringspot virus (PRSV). The first PRSV-resistant GM papaya expressing a PRSV coat protein gene was developed by USA scientists in 1992. The first commercial GM papaya cultivars derived from the event was approved by the US government in 1997. Development of transgenic papayas has been focused on vaccine production and limited agricultural traits, including insect and pathogen resistance, long shelf life, and aluminum and herbicide tolerance. Approximately 17 countries, including the USA and China, produced transgenic papayas and/or commercialized them, which provoked studies on biosafety assessment and development of GM-detection technologies. For the biosafety assessment of potential effects on human health, effects of long-term feeding to model animals have been studied in terms of toxicity and allergenicity. Studies on environmental safety assessment include influence on soil-microbial biodiversity and transfer to soil bacteria of GM selection markers. Many countries, such as Korea, the European Union, and Japan, that have strict regulations for GM crops have serious concerns about unintended introduction of GM cultivars and food commodities using unauthorized GM crops. Transgene- and/or GM event-specific molecular markers and technologies for genomics-based detection of unauthorized GM papaya have been developed and have resulted in the robust detection of GM papayas.

• Journal of Plant Biotechnology
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• v.43 no.1
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• pp.91-98
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• 2016

The growth area of living modified (LM) cotton has steadily increased every year, since its first commercialization in 1996. Development of environmental risk assessment tools and techniques for LM cotton is required for ecosystem safety. We therefore developed multiplex PCR assays for simultaneous detection of two (MON15985, MON531) and four (GHB614, LLCOTTON25, MON88913 and MON1445) LM cotton events approved in Korea, with event specific primer pairs. The PCR reactions were optimized by using event specific primers of six LM cottons at various concentrations. The reactions allows amplification of estimated amplicons of MON15985 (214 bp), MON531 (270 bp), GHB614 (119 bp), LLCOTTON25 (164 bp), MON88913 (276 bp), and MON1445 (389 bp) from multiplex PCR reactions. The multiplex PCR assay developed allowed that two annealing steps (15 cycles at $55^{\circ}C$ and 25 cycles at $60^{\circ}C$) were performed for amplification of distinguished two LM cottons, and only one annealing step (50 cycles at $60^{\circ}C$) was necessary for tetraplex PCR. Primer extension step of all PCR reactions was skipped for time-effective amplification. Our methods suggest that two multiplex PCR assays can be cost-effective and a rapid diagnostic tool for environmental LMO monitoring of six LM cottons.

• Journal of the Korean Geophysical Society
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• v.2 no.1
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• pp.9-26
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• 1999

The Ulleung Basin (Tsushima Basin) in the southwestern East Sea (Japan Sea) is floored by a crust whose affinity is not known whether oceanic or thinned continental. This ambiguity resulted in unconstrained mechanisms of basin evolution. The present work attempts to define the nature of the crust of the Ulleung Basin and its tectonic evolution using seismic wide-angle reflection and refraction data recorded on ocean bottom seismometers (OBSs). Although the thickness of (10 km) of the crust is greater than typical oceanic crust, tau-p analysis of OBS data and forward modeling by 2-D ray tracing suggest that it is oceanic in character: (1) the crust consists of laterally consistent upper and lower layers that are typical of oceanic layers 2 and 3 in seismic velocity and gradient distribution and (2) layer 2C, the transition between layer 2 and layer 3 in oceanic crust, is manifested by a continuous velocity increase from 5.7 to 6.3 km/s over the thickness interval of about 1 km between the upper and lower layers. Therefore it is not likely that the Ulleung Basin was formed by the crustal extension of the southwestern Japan Arc where crustal structure is typically continental. Instead, the thickness of the crust and its velocity structure suggest that the Ulleung Basin was formed by seafloor spreading in a region of hotter than normal mantle surrounding a distant mantle plume, not directly above the core of the plume. It seems that the mantle plume was located in northeast China. This suggestion is consistent with geochemical data that indicate the influence of a mantle plume on the production of volcanic rocks in and around the Ulleung Basin. Thus we propose that the opening models of the southwestern East Sea should incorporate seafloor spreading and the influence of a mantle plume rather than the extension of the crust of the Japan Arc.

• Korean Journal of Environmental Biology
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• v.41 no.3
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• pp.229-246
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• 2023

The bitterling (Cyprinidae, Acheilongnathinae) is a temperate freshwater fish with a unique spawning symbiosis with host mussels. Female bitterlings use their extended ovipositors to lay eggs on the gills of mussels through the mussel's exhalant siphon. In the present study, in April of 2020, we investigated spawning frequencies and patterns of three bitterling fish species in host mussel species in the Nakdong River basin (Hoecheon). During field surveys, a total of four bitterling and three mussel species were found. We observed bitterling's spawning eggs/larvae in the three mussel species: Anodonta arcaeformis(proportion spawned: 45.5%), Corbicula fluminea(12.1%), and Nodularia douglasiae (45.2%). The number of bitterlings' eggs/larvae per mussel ranged from 1 to 58. Using our developed genetic markers, we identified the eggs/larvae of each bitterling species in each mussel species (except for A. macropterus): A. arcaeformis (spawned by Acheilognathus yamatsutae), C. fluminea (A. yamatsutae and Tanakia latimarginata), and N. douglasiae (A. yamatsutae, Rhodeus uyekii, and T. latimarginata). Approximately 57.6% of N. douglasiae mussel individuals had eggs/larvae of more than one bitterling species, suggesting that interspecific competition for occupying spawning grounds is intense. This is the first report on bitterling's spawning events in the Asian clam C. fluminea from Korea; however, it should be ascertained whether bitterling's embryo undergoes successful development inside the small mussel and leaves as a free-swimming juvenile. In addition, the importance of its conservation as a new host mussel species for bitterling fishes needs to be studied further.