• Journal of Forest and Environmental Science
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• v.34 no.1
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• pp.66-70
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• 2018

Preliminary investigation and analysis of the effectiveness of controlling the number of ecosystem disturbance fishes residing in Togyo reservoir using the native carnivorous fish species were performed. The data were collected from August 2011 to November 2016. The release of native carnivorous fish species was carried out from the end of May, 2012 to the end of July, 2016, considering fishing ban period of Siniperca scherzeri. The comparative abundance of Lepomis macrochirus was found to be 12.8% in the first year and increased a little bit after releasing the native carnivorous fish. However, it decreased to 3.9% in the last year showing a value of less than 5%. On the other hand, the Micropterus salmoides populations tended to increase after the release of native carnivorous fish species. This seems to be the result of the segregation of habitat by interspecific competition with S. scherzeri. The M. salmoides moved from inside of the lake to edges, and to influent tributaries. Stable isotope analysis showed that Channa argus had the highest levels of nutrition, S. scherzeri and M. salmoides were in competition, and L. macrochirus was used as a feed source for released species. Changes of the fish community in the Togyo reservoir was represented by the rank abundance curves based on the results of the fish fauna. As a result, the fish group in incoming tributaries are somewhat disturbed after the release of the native carnivorous species. Similarly, the fish group in the reservoir were disturbed as well but it's gradually stabilizing afterwards. Therefore, the control of the ecosystem disturbance species using the native carnivorous fish of Korea is effective and helps to stabilize the fish community in the lake.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.1
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• pp.33-43
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• 2004

A carbon budget model was constructed and analyzed for the Bangjukpo surf zone ecosystem in southern Korea by using the NETWRK. The model consists of 11 living and 1 non-living groups. Using boxes and arrows, a topological map was created to depict biomasses of each group and exchange rates between them. The system includes primary producers of phytoplankton and benthic algae, primary consumers of particle feeding zooplankton, carnivorous zooplankton, meiobenthos, malacostracans and bivalves, and top consumers of detrivorous, omnivorous, carnivorous and piscivorous fishes. The surf zone ecosystem was analyzed by means of network analysis, showing total system throughput of $574\;gCm^{-2}yr^{-1},$ development capacity of $1,876\;gCm^{-2}yr^{-1},$ ascendancy value of $768\;gCm^{-2}yr^{-1},$ Finn cycling index of $4.4\%$ and internal relative ascendancy of $27\%.$ These results were compared with similar data from other systems.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.2
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• pp.122-128
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• 2004

On the basis of monthly samples, we investigated the seasonal variation and feeding habits of amphipods inhabiting Zostera marina beds in Gwangyang Bay. Dominant species $(>1\%$ of the total number of amphipods) consist of 5 gammarids (Gammaropsis japonicus, Jassa slatteryi, Pontogenia rostrata, Atylus collingi and Ceinina japonica) and 1 caprellid (Caprella tsugarensis). Mean densities of amphipods varied from the highest of $63,148\;ind.\;m^{-2}$ in-May to the lowest of $1,247\;ind.\;m^{-2}$ in September. G. japonicus and J. slatteryi dominated in summer whereas C. japonica in autumn and winter. C. japonica was found to be a carnivorous feeder consuming mainly harpacticoid copepods and unidentified crustaceans, whereas G. japonicus, J. slatteryi, and C. tsugarensis consumed both phytoplankton and detritus. Seasonal densities of amphipods were significantly related with the shoot standing crop of the eelgrass and its epiphyte. Also densities of amphipods displayed significant difference in related with the shoot density of the eelgrass among sampling stations. These results suggest that the biological interactions between the eelgrass and amphipods as well as between the carnivorous and the herbivorous amphipods may be important in the seasonal variation of amphipods inhabiting Z. marine beds.

• Korean Journal of Ecology and Environment
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• v.56 no.3
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• pp.218-228
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• 2023

Invasive predators are one of the most damaging species groups to biodiversity. In the Nakdong River, the lake skygazer Chanodichthys erythropterus is a dominant species that is fiercely carnivorous and a concern for commercial fish. Although it is important to understand the ecological characteristics related to the feeding habit, studies on the diets of lake skygazer in Nakdong River have been limited to studies of gut contents. In this study, the trophic position (TP) and feeding habits of C. erythropterus were studied by calculating TPs using samples collected from 13 sites throughout the Nakdong River. Compound-specific isotopic analysis of amino acids provided reliable TPs from the muscle of Lake skygazer C. erythropterus without any isotope baseline. The results were approximately 3 to 3.6 and suggesting a carnivorous but size-dependent prey variation. In particular, the TP variability of C. erythropterus observed in the Nakdong River showed that it had a selective feeding habit compared to carnivorous fish species of relatively similar trophic levels.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2005.11a
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• pp.149-150
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• 2005

• Journal of Ecology and Environment
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• v.44 no.1
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• pp.1-7
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• 2020

Background: Fish body size is a major determinant of freshwater trophic interactions, yet only a few studies have explored the relationship between the fish body size and trophic interactions in river upstream. In this study, we investigated the relationship between the body size and trophic position (TP) of Coreoperca kawamebari (Temminck & Schlegel, 1843) in an upstream of the Geum River. Results: A stable isotope analysis (based on δ¹⁵N) was used to determine the TP based on the body size of C. kawamebari. The regression analysis (n = 33, f = 63.840, r² = 0.68) clearly showed the relationship between the body length and TP of C. kawamebari. The TP of C. kawamebari was clearly divided by body size into the following classes: individuals of size < 10 cm that feed on insects and individuals of size > 10 cm feed on juvenile fish. This selective feeding is an evolutionarily selective tendency to maximize energy intake per unit time. Furthermore, the diet shift of C. kawamebari was led by different spatial distributions. The littoral zone was occupied by individuals of size < 10 cm, and those of size > 10 cm were mainly in the central zone. The littoral zone can be assumed to be enriched with food items such as ephemeropterans and dipterans. Conclusion: The TP of C. kawamebari, as a carnivorous predator, will have a strong influence on biotic interactions in the upstream area of the Geum River, which can lead to food web implication.

• 한국해양학회지
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• v.21 no.1
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• pp.25-33
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• 1986

Ontogenetic food habits of the four most abundant fish species in seagrass neadows of Redfish Bay, Texas, were examined quantitatively during 1982-1983. The darter goby (Gobionellus bolelsoma) and pinfish (Lagodon rhomboides) were trophic generalists, which used a wide range of food items. The darter goby had relatively diverse, omnivorous diet which included amphipods, copepods, polychaetes, filamentous algae, diatoms, and detritus. This species did not show distinct ontogenetic changes in foodpreferences. Unlike the darter goby, the pinfish showed ontogenetic progression of four feeding stages. An initial feeding stage was a planktivorous stage in which copepods were int major food items, followed by a carnivorous stage in which amphipods became the major food items, an omnivorous stage in which filamentous algae, diatoms, amphipods, and polychaetes were the major food items, and finally a herbivorous stage in which seagrass pieces with attached epiphytes and their debris were the major food items. The code goby (Gobiosoma robustrm) and Gulf pipefish (Syngathus scovelli) appeared to be relatively specialized in food havits as carnivorous. Similar ontogenetic changes in food habits were observed for these two species, i.e.initially, copepods were the major food items, followed by a gradual transition to amphipods with growth.

• Applied Microscopy
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• v.38 no.1
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• pp.21-28
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• 2008

Carnivorous plants vary in their unique features of morphology, ultrastructure and biochemical properties by species. Furthermore, prey-capturing mechanism as well as structural and physiological adaptations have been used for grouping various carnivorous species. In Drosera plants, glandular trichomes, which develop in the leaf epidermis, are known to play the most important role during the prey capturing process. The present study examined such trichomes, focusing on the glandular type, in leaves of Drosera anglica using scanning and transmission electron microscopy. Three types of rudimentary glandular trichomes were found to develop within the folded leaf primordia and immature leaf during early development. The first type, stalked glandular trichomes (Type I), occurred on the margin and upper epidermis of the leaf. With maturation, the longest glandular trichomes having lengthy stalks, ca. $2.2{\sim}5.1\;mm$, developed along the margin, while shorter stalked trichomes, ca. up to $200\;{\mu}m$, were found on the inner leaf blade. The shorter ones consisted of a globose head having two layers of secretory cells, parenchyma bell cells and tracheids and a multicellular stalk. The stalks gradually decreased in length in centripetal fashion. The second type, Type II, having ca. $15{\sim}30\;{\mu}m$ short stalks, also developed along the inner blade. Both types secreted mucilage from the secretory cells which had a thin cell wall and cuticle layer. The sessile six-celled glandular trichomes were the third type, Type III, and were $25{\sim}40\;{\mu}m$ in length. They were distributed most commonly throughout the upper and lower epidermis, petiole and even on the stalk surfaces of the first two types of trichomes. The third type was also found to be involved in the active secretion. In prey capturing leaves, all trichome types secreted substances through thin cuticles in the head cell wall, which exhibited relatively loose wall components.

• Journal of Yeungnam Medical Science
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• v.28 no.2
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• pp.105-115
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• 2011

Mercury is a toxic, persistent pollutant that bioaccumulates and biomagnifies through food webs. People are exposed to methyhnercruy mainly through their diet, especially through the consumption of freshwater and marine fish and of other animals that consume fish (e.g., marine mammals). All humans are exposed to low levels of mercury. Dietary patterns can increase exposure to a fish-eating population where the fish and seafood are contaminated with mercury. The primary toxicity targets of mercury and mercury compounds are the nervous system, kidneys, and cardiovascular system. It is generally accepted that developing organ systems are most sensitive to the toxic effects of mercury. The fetal-brain mercury levels appear to be significantly higher than the maternal-blood mercury levels, and the developing central nervous system of the fetus is currently regarded as the main system of concern as it demonstrates the greatest sensitivity. The subpopulation that may be at greater risk for mercury toxicity are those exposed to higher levels of methylmercury due to carnivorous fish, including sharks.

• The Journal of the Korea Contents Association
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• v.9 no.2
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• pp.173-180
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• 2009

In the recent past, the impression expressed by a human body expanded from that of aesthetic beauty to deformed organic medium influenced by environment. And the advancement in digital technology had made it possible to represent the deformed and distorted images of human body more realistically. Consequentially, these exaggerated physical images leave audiences with a feeling of grotesqueness. Chris Cunningham is a British director who mainly focuses on grotesque body as his subject matter using digital media. This paper will explore Chris Cunningham's work and his final goal through analyzing his carnivorous, uncanny grotesque body images, making use of the figital media, at each of his different levels.