• Korean Journal of Environmental Biology
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• v.40 no.2
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• pp.148-156
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• 2022

Ecological occupation in irrigation ponds is a well-acknowledged fact that is essential for biodiversity conservation in agricultural ecosystems. However, there are few studies on the ecological functions and relationship between a paddy field and irrigation using macroinvertebrates in an environmentally friendly paddy field. The objective of this study is to identify the community and distribution characteristics of macroinvertebrates in an agricultural paddy field and irrigation pond ecosystems, and to provide basic data on the ecological function of an environmentally friendly paddy field. Macroinvertebrate sampling was conducted from May to September in an agricultural paddy field and irrigation pond in an environment-friendly paddy field in Boryeong city. We conducted a study to identify the distribution characteristics using macroinvertebrate species analysis, such as Functional Feeding Groups (FFGs), Habitat Oriented Groups (HOGs), rarefaction curve, and a two-way dendrogram. A total of 37 species of macroinvertebrates in 28 families, 13 orders were collected study during the period of the investigation. Dominant taxa of macroinvertebrates included Coleoptera, Hemiptera, and Odonata. In terms of FFGs, predators and gathering collectors accounted for approximately 70%, in relation to HOGs, and climbers and swimmers occupied more than 50% from both the paddy field and irrigation pond. With respect to the rarefaction curve, the irrigation pond (July) was high as E (S, 141)=18 species, while the paddy field (May) was comparatively low as E (S, 141)=9 species. In conclusion, our results revealed that macroinvertebrates, such as Notonecta triguttata, Peltodytes intermedius, Appasus major, Laccotrephes japonensis, Appasus japonicus, Sigara substriata, Enochrus simulans, and Sternolophus rufipes, were used as a habitat and spawning ground in both paddy field and irrigation pond. The irrigation pond appears to be a very important spawning ground for macroinvertebrates.

• Journal of the Korean Society of Food Culture
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• v.5 no.2
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• pp.217-228
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• 1990

An ecological study of food and nutrition was conducted among 198 children, 6 to 12 years old, of the Songmyun elementary school and Samsong elementary school, located in remote villages of Chungchun-myun, Goisan-gun, Chung Buk Province between July 11 and 16, 1988. The results were summarized as follows. In regard to frequency of skipping breakfast, 3.3% of subjects skipped every morning; 15% often skipped; and the others never skipped. The most common reason for skipping a meal was lack of appetite. 6.6% of subjects often skipped an evening meal because of delayed meal preparation by a mother who returned home late. The survey found that 5.1% of subjects skipped a lunch at school. The reasons for skipping lunch were the mother’s being too busy to prepare a boxed lunch; a school bag too heavy to carry for a long distance to school; no adequate side-dishes for the boxed lunch. Growth patterns of those children having poor food habits, were reflected in lower figures in arm circumference and weight for height. The percentage of children having meals with their family on weekdays was 84.7% for breakfast; 85.6% for evening meal. About 7% of subjects had many dislikes and 74.1% had some dislikes in what they ate; 18.9% had good food preferences. There was a strong correlation between appetite or food preferences and anthropometric measurements or nutrient intake. Boiled rice was the predominant dietary staple, and principal sources of protein taken by subjects at home were soy beans and soy products. Regarding the boxed lunch prepared at home, most popular was one with only one kind of side-dish, including kimchee. 43.4% of the side-dishes were prepared with vegetables only. As for between meal snacks, milk and milk products, fruits and breads were popular among the subjects. The survey found that the children liked fruits, yogurt, corn, Chajang noodle; in contrast, lowest preference was for soup made with bones, curried meat with rice, and aromatic vegetables. The survey discovered a local dietary characteristics; 46.2% of the children customarily ate frog meat, an unconventional food.

• Journal of Ecology and Environment
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• v.34 no.2
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• pp.223-235
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• 2011

Juncus effusus is mostly found in freshwater wetlands and is widely used for landscaping and creating artificial wetlands due to its high ecological value. J. effusus tends to dominate during the early stage (3-10 years) of the second succession in abandoned paddy fields. This study focused on the environmental characteristics of J. effusus to create habitat for an endangered species, Nannopya pygmaea, which lives in wetlands dominated by J. effusus. Considering the distribution of J. effusus and N. pygmaea, 63 quadrats at eight wetlands were investigated between May and June 2006 during the critically dry period. Fifty-three species from 28 families co-occurred with J. effusus, and Persicaria thunbergii was the most abundant (63.5%). The optimal ranges of distribution (ORD) for the water variables were water depth, -2 to 10 cm; dissolved oxygen, 0.99-3.55 mg/kg, conductivity (CON), 23.40-115.40 ${\mu}s/cm$, total dissolved solid, 12.53-57.60 mg/L; pH, 5.00-6.87; $K^+$, 0.11-1.46 mg/L; $Ca^{2+}$, 1.53-5.85 mg/L; $Na^+$, 3.16-7.47 mg/L; $Mg^{2+}$, 0.11-1.96 mg/L; $NO_3$-N, < 0.001-0.072 mg/L; $NH_4$-N, 0.005-0.097 mg/L; and $PO_4$-P, 0.006-0.047 mg/L. ORDs for the soil variables were water content, 1.05-2.96%; loss-on ignition method (LOI), 5.07-7.81%; CON, 23.70-59.70 ${\mu}s/cm$; pH, 4.40-5.16; extracted (e) $K^+$, 4.34-15.73 cmol/kg; $eCa^{2+}$, 31.56-191.56 cmol/kg; $eNa^+$, < 0.01-2.61 cmol/kg; eMg, 0.04-19.82 cmol/kg; $eNO_3$-N, 0.514-1.175 mg/kg; $eNH_4$-N, 0.033-0.974 mg/kg, $ePO_4$-P, 0.491-11.552 mg/kg; total nitrogen, 0.016-0.200%; and total carbon, 1.06-2.37%. The appearance of rush during early succession indicated relatively lower levels of these physicochemical parameters, and that ORDs should be maintained for the J. effusus community.

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.379-387
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• 1999

During the past several decades, electricity generating plant increased with remarkable rapidity in Korea. Recently the increase has been much more rapid as the rate of industrialization has accelerated. Construction of nuclear power plants in coastal areas inevitably caused the perturbation of critical coastal habitats and thus influenced marine algal species composition. Particularly, an increase in the building of nuclear power plants led the amounts of heat discharged to increase exponentially. As far as the effects of cooling water and thermal discharges are concerned, benthic marine algae are likely to be vulnerable to a discharge. Heated effluents from nuclear power plants, with the temperature rises of 7~12$^{\circ}C$ under normal operating and design conditions, are discharged through the discharge canal and into natural water bodies. It is clear that the characteristic marine algal community is developed in the area affected by the thermal discharges; i.e. low species richness and low species diversity. Nevertheless, it is worthwhile to note that elevated temperatures exert differential effects depending on the algal populations. Benthic marine algae grown at the discharge canal can be regarded as warm tolerant species. 35 species (4 blue-green, 9 green, 8 brown and 14 red algae) of marine algae occurred more than 20eye frequency at discharge canal of three nuclear power plants in the east coast during 1992 ~ 1998 and thus can be categorized as warm tolerant species in Korea. To minimize the ecological impacts of waste heat on benthic marine algae, it is recommended that, in the future, nuclear power plants will have to employ some form of closed-cycle cooling for the condensers.

• Korean Journal of Cognitive Science
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• v.26 no.2
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• pp.167-207
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• 2015

This study focused on the awareness and coping methods of psychological trauma and human suffering in the contemporary era after the development of posttraumatic stress disorder(PTSD) including the situations in the Korean society, and proposed principles for an alternative paradigm of trauma recovery. Trauma is defined as an 'external' stress causing chronic suffering mediated by memory, and the American Psychiatric Association approved PTSD in the Diagnostic and Statistical Manual of Mental Disorders in 1980. The development of PTSD empowered moral legitimacy to the victims, opened a successful way to treatment, and accomplished explosive amount of research in the area of neurobiology and cognitive neuroscience. However, this also narrowed the understanding of human suffering, and the importance of an alternative coping method which overcomes the limitations of technical intervention became overlooked. Moreover, the Korean society has an underlying mechanism of replacing the matter of trauma to a problem of an individual. This is shown among the historical context of splitting and denial, and among medicalized bureaucracy. Trauma should be acknowledged as a social suffering, and searching for an alternative paradigm is in need. This study suggested the following principles; seeking for truth and justice, survivor as the agent of recovery emphasizing the responsibility of the community, ecological adaptations of recent bio-psychological achievements, and finally putting emphasis on continuous discussions about the definition of recovery.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.584-594
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• 2016

This research empirically analyzes, from an ecological perspective, whether socio-economic factors of the regions in which the elderly live have any actual influence on thoughts of suicide on the part of the elderly. Microscopic data either included outliers in part of the variables, including income and other variables of that type, from among source data from investigations into actual conditions of the elderly in 2014. Regarding macroscopic data, the indices that represent social and economic situations in each region, which were provided by KOSIS, were selected. Regarding the method of analysis, hierarchical or multi-level analysis models were applied by considering special hierarchical characteristics and heterogeneity at the personal and regional levels. The analyses showed that the following had statistically significant influences: 1. the cost-of-living index and the national basic supply and demand rate of the region; 2. the extent of natural disaster damage; and 3. the number of leisure and welfare facilities for the elderly, compared to the elderly population. Based on the results, proposals are made for systematic and practical endeavors in the community.

• Journal of Environmental Impact Assessment
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• v.21 no.6
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• pp.859-877
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• 2012

In this study, Echo-sounder($E_s$) monitoring methodology was applied to test environmental impacts of artificial weirs(SCW and JSW) in the Yeongsan River on fish community and habitat structures at first time, and was compared with conventional fish sampling methodologies($C_s$). For the Es monitoring in the fields, parallel transect methods was employed in determining the survey distance interval with every 125 m within the upper-lower 2 km of the weirs. Four different fish sampling gears such as casting nets, kick nets, fyke nets, and gill nets were used for applications of $C_s$ monitoring methodology. According to the Echo-sounder monitoring, fish density, expressed as a number of individuals per square meter, along the longitudinal axis of the weir was significantly greater(JSW, t = 3.506, n = 30, p < 0.001) in the down-river reach of the weir than in the up-river reach. Also, fish density along the vertical water column was highest at mid-depths of Seungchon weir, which has simple habitat substrates, while fish density was highest at hypolimnetic depth of Juksan weir. According to fish sampling by the $C_s$ methodology, the fish compositions decreased as the river goes upward, and significant differences(JSW, t = 0.248, n = 30, p < 0.05) in the compositions of fish species occurred between up-reach and down-reach of the weirs. The dominant species near the two weirs were Opsarichthys uncirostris amurensis, Hemiculter eigenmanni and Coilia nasus. Overall, our fish and habitat data, based on $E_s$ and $C_s$ monitoring methodologies, suggest that the weirs disturbed the rivers due to initial habitat disturbances by the weir constructions as well as the barrier roles of weirs on fish passage and migrations. More long-term scientific and systematic fish impact monitoring and assessments($E_s$ and $C_s$) are required in the future to predict changes of ecological structures and functions on the constructions of the weirs.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.2
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• pp.76-86
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• 2012

Macrozoobenthos were collected from 24 sites using small grab ($0.05m^2$) in order to see the spatial distribution of them at Sueocheon stream at the northern part of Gwangyang Bay during summer season when the maximum ecological processes are occurring. A total of 44 species of macrozoobenthos occurred, and their mean density was $789individuals/m^2$. Mollusks was the dominant faunal group accounted for 43.1% and 86.8% of the whole community density and biomass, respectively. Top five dominant species were a molluscan, Corbicula japonica (40.7%), two polychaete worms, Neanthes japonica (19.3%) and Heteromastus filiformis( 8.1%), and two crustaceans, Paranthura japonica (6.9%) and Jaeropsis sp. (6.9%). Species diversity index was very low with mean value of 1.12 and maximum value was recorded at the river mouth. At the upper stream, a brackish water species such as Corbicula japonica showed their maximum population density. The overall distribution of stream macrobenthos showed a rather simple pattern along with salinity and grain size gradients with few brackish water species occurring at coarse sediments in the stream but more diverse faunas inhabiting fine sediments in the river mouth.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.5B
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• pp.331-343
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• 2012

In this study, the site investigation for fish was performed in the 15 km of Hongcheon river including Oancheon stream. The river ecosystem health was evaluated using the field data for fish. The field survey was carried out at 9 sites, 4 times from August to November 2011. The ecological diversity, including dominance, evenness, and richness and the ecological health using IBI and QHEI were evaluated. The result shows that the mean IBI in the 9 sites is in good-common condition, but the downtown section has a common-worse condition. The result evaluated by QHEI shows optimum-good condition. Also, the habitat suitability index for Pseudopuntungia tenuicorpa, which is one of endangered species, was evaluated, and then the environment flow was calculated by using the PHABSIM model. The previous research in the literature reports that Acheilognathus signifer, one of the endangered species, inhabited in Hongchen river. However, the existence of Acheilognathus signifer was not found in the recent research and this study. Thus, the physical habitat condition for Acheilognathus signifer was evaluated using the field data in the previous study. Also, the habitat improvement for Acheilognathus signifer in Hongcheon river was proposed.

• The Korean Journal of Pesticide Science
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• v.10 no.3
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• pp.189-195
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• 2006

The purpose of the current study was to develop a standard method to assess the ecological effect of pesticides using the representative Korean freshwater cladocerans. The indigenous cladocerans, Daphnia obtusa, Daphnia sp., Moina macrocopa, Simocephalus vetulus and Daphnia magna formally endorsed by the major international organizations were tested to select optimal culture media in laboratory condition. All of the Korean water flea tested showed good growth and fecundity in the moderately hard water ($CaCO_3$ ranged 80 to 100 mg $L^{-1}$) and soft water ($CaCO_3$ ranged 40 to 48 mg $L^{-1}$). However, considering that the total hardness of fresh water collected from 5 rivers ranged from 60.2 to 127.2 mg $L^{-1}$ ($CaCO_3$) and Ca deficiency could be a major determinant of species success and community structure among crustacean zooplankton, the present study suggests that the optimal water hardness for growing Daphnia sp., Daphnia obtusa, Moina macrocopa and Simocephalus vetulus is $80{\sim}100$ mg $L^{-1}$ of $CaCO_3$.