• Korean Journal of Ecology and Environment
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• v.56 no.3
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• pp.229-241
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• 2023

Microphysogobio rapidus is designated as endangered species class I by Ministry of Environment, and its distribution and population have been gradually declining, and it is now limited to the Nam River and some tributary streams of the Nakdong River Watershed. For the restoration of this highly endangered species, it is important to identify the causes of the decline and establish appropriate restoration plans. However, due to lack of basic data and ecological research, most steps are stagnant. Therefore, in this study, we identified the differences in the physical, biological, and sociological habitats between current and past distributed sites through field surveys and literature reviews. As a result of the field survey, there were differences in conductivity between the current and past distributed sites, and fish communities were also showed differences. The literature data also showed that the physico-chemical values of the past distributed sites were generally unfavorable, which generated negative consequences on biological factors. In particular, the effects of urbanization were found to be a major factor affecting the habitat of M. rapidus. Habitat stabilization is crucial for the recovery of this endangered species. However, in the past distributed sites, disturbances such as stream development and weir construction have altered streams physico-chemically and result in changes of M. rapidus. Therefore, a comprehensive plan that considers both stream connectivity and water quality is needed to manage and restore the habitat of M. rapidus.

• Korean Journal of Environment and Ecology
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• v.20 no.4
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• pp.365-373
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• 2006

With a few exceptions, Korean lakes are artificially constructed for multi-purposes throughout the country. In the majority of cases, a lake is in a multiple series of reservoirs along a river or is an estuary Moreover, nutrient supplying activities (including sand extraction) and biomanipulation(esp., overfishing and fish introduction) are omnipresent in most cases. Furthermore, there is an Asian monsoon every year. In brief, europhication and algal blooms break out as a result of complicated causes. However limnological monitoring and scientific working programs are in the course of beginning. The question is what kind of strategy is desirable to establish a solid limnological database for the efficiency of the restoration process in each Korean reservoir We present light monitoring cases on the basis of algal and some physicochemical data in 2005. Do they give some useful informations despite their simplicity. Based on physicochemical factors and phytoplankton data using Utermohl method and Canonical Correspondence Analysis(CCA) were performed for Lake Cheongpyeong, Lake ASan, Lake Namyang, and Lake SapGyo. The results of CCA showed that Lake Cheongpyeong was different from the other three Lakes at estuary. Also each Lake at estuary was slightly different from one other. This result would encourage to initiate building an adequate Korean reservoir-ecosystem understanding and models for better ecological management despite the limited data. However, the results also indicate to sustain collecting ecological data and building database to interpret the Korean ecological reservoir model.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.179-179
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• 2022

최근 화두가 되고 있는 환경문제 중 하나로 녹조현상을 꼽을 수 있다. 녹조란 남세균이 대량 증식함으로써 물빛이 녹색으로 변하는 현상으로, 영양염류 및 수온 등 이화학적 요소뿐만 아니라체류시간과 같은 수리학적 요인까지 모두 충족되었을 때 발생한다. 심하면 고밀도의 스컴(scum)을 형성하며 독소와 악취를 동반하기도 한다. 유해 남세균이 생성하는 마이크로시스틴(microcystin, MC)이 함유된 물을 입 또는 코로 섭취시 간을 손상시킨다는 보고가 있으며, 최근 해외에서는 MC가 미세먼지처럼 공기 중에 떠다니다 수변에서 생활하는 사람의 호흡기로 들어가 건강 피해를 줄 수 있다는 연구가 속속 나오고 있다. 본 연구는 우리나라 최초의 수질개선용 댐인 영주댐을 연구 대상으로 삼아 수질 모델링을 구축하고 영주댐 운영에 따른 댐 상·하류 조류 변화를 정량적으로 분석하였다. 조류의 강도를 추정하는데 클로로필-a 농도를 사용하였으며, 분석 도구로는 국립환경과학원이 수질예측 및 평가 시 사용하는 EFDC(Environmental Fluid Dynamics Code) 모형을 활용하였다. 대상 구간의 실제 폭, 하상고 분포 등을 고려하여 수표면 격자망을 구현하였으며, 환경부에서 제공하는 수위 및 DO, TN, T-P, 클로로필-a 등을 활용하여 EFDC 모형의 수리 및 수질 재현성 검토를 하였다. 검·보정된 EFDC 모형으로 영주댐의 방류량 변화 및 댐의 개방과 같은 수리학적 요인을 제어하여 특정 지점의 조류 변화를 분석하였다.

• Proceedings of the Korean Society of Community Living Science Conference
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• 2003.11a
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• pp.141-141
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• 2003

소득수준의 향상됨에 따라 환경과 건강에 대한 관심이 높아지면서 유기농산물에 대한 소비자 선호도가 증가하고 있음에도, 유기농산물의 품질에 대한 의구심 등으로 소비확대를 제약하는 요인들은 상존하고 있으며, 특히, 중요 식량자원인 쌀의 경우 유기농 쌀의 식품영양학적 품질 구명 연구는 미진한 실정이다 본 연구는 유기농 쌀의 품질 인증 및 식품영양학적 특성 구명에 기초자료로 활용할 목적으로 오리농법과 관행농법 및 표준시비법(대조구)으로 재배된 추청벼를 현미와 백미로 각각 도정한 후 영양성분 조성을 분석하였고, 동일조건에서 취반한 쌀밥의 관능적 특성을 조사하였다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.163-164
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• 2001

생선회 육질의 단단함(toughness)은 생선회의 맛을 좌우하는 중요한 요인이며, 육질의 단단함은 결합조직의 주성분인 collagen의 함량 및 분포 형태에 의해서 결정되어지는 어종에 따른 고유의 단단함(background toughness)과 사후 ATP의 분해와 함께 일어나는 myosin과 actin의 결합에 의한 actomyosin복합체의 형성에 따른 근육수축에 의한 단단함(actomyosin toughness)으로 이뤄진다. (중략)

• Monthly Duck's Village
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• s.174
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• pp.32-33
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• 2017

본 시험은 냉동 및 해동 방식에 따른 토종오리 고기의 이화학적 특성을 조사하기 위해 수행하였다. 처리구는 8주령 오리육을 대조구(Control)로 하고 처리구는 냉동방식 2가지(급냉, $-50^{\circ}C$; 완냉, $-20^{\circ}C$)과 해동방식 2가지(완해동, $4^{\circ}C$ 냉장해동; 급해동, $13^{\circ}C$ 유수해동;의 $2{\times}2$ 복합요인으로 하여 총 5처리구, 처리구당 3반복, 반복당 3점(2수/점)으로 나누었다. 공시재료는 각 처리구에서 발생된 8주령 토종오리 수컷을 처리구당 18수씩 선별하여 도압하고 1개월간 저장 후 분석에 이용하였다. 명도는 완냉시키거나 완해동할 때에 대조구와 유의적인 차이가 있었으나(P<0.05), 적색도와 황색도는 처리구간 유의차가 없었다. 가열감량과 보수력은 급냉시키거나 급해동시킬 때 대조구에 비해 유의적으로 높게 나타났으나(P<0.05), 전단력은 대조구에 비해 낮게 나타났다(P<0.05). 가열감량, 전단력, 보수력은 냉동 처리구 사이에서는 유의적인 차이를 보이지 않았으나, 가열감량은 급해동과 완해동 사이에 유의차가 나타났다(P<0.05). 수분, 지방, 단백질, 조회분의 함량은 냉동 처리구와 대조구 사이에서 유의차가 없었으나, 수분함량은 급해동 처리구에서 완해동 처리구에 비해 유의적으로 높게 나타났으며(P<0.05), 단백질 함량은 완해동 처리구에서 대조구에 비해 높게 나타났으나(P<0.05) 해동 처리구간에는 유의적인 차이가 없었다. 지방과 단백질 함량은 해동 처리구 사이에서 유의적인 차이를 보이지 않았다. 결론적으로, 본 시험에서는 냉동과 해동 방식에 따른 오리고기의 특징을 보여주고 있으며, 이런 결과들은 토종오리 산업과 오리육 생산 산업에 큰 도움이 될 것이라 사료된다.

• 한국노년학
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• v.31 no.4
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• pp.905-923
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• 2011

The purpose of this study is to examine factors affecting the conflict between grandparents raising grandchildren and adult children. The data were based on the panel survey to explore korean retirement and income study conducted by National Pension Service in 2009. For this study, 287 parenting grandparents rearing grandchild are selected from the survey. Included variables are a demographic factor, a economic factor, a caregiving-related factor, a health factor, and a family relationship factor. The data were analyzed using descriptive statistics, t-test, co-relation and logistic regression, with SPSS WIN 18.0 program. The results are as follows: First, when grandparents are male, older, highly educated, having no religion, and unemployed, a conflict with their adult children grows. Second, when grandparents do not have earned income or financial income, but have private income transfers, a conflict with their adult children is high. Third, when grandchildren are younger, there are no caregiving rewards, economic activities suspension or reduction because of caregiving, a conflict with their adult children is strong. Also, when grandparents' physical health is good, but their mental health is poor, a conflict with their adult children increases. Fourth, when grandparents' satisfactions with family relationship and spouse relationship are low, but their satisfaction with adult children relationship is high, a conflict with their adult children rises. This study suggests that unlike in the past, grandparents raising grandchildren can no longer make sacrifice themselves for their adult children, but they expect proper exchange between parents and children. Therefore, there needs to be understanding of grandparents raising grandchildren and further studies of a conflict between grandparents raising grandchildren their adult children.

• Food Science and Preservation
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• v.17 no.3
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• pp.370-375
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• 2010

Cherries (Prunus avium L) were selected at the light red (LR) and dark red (DR) stages of maturation. Soluble solid content and the physicochemical properties of fresh 'Bing' cherries were analyzed to identify an instrumental nondestructive attribute reflecting changes in sweetness. Soluble solid content was significantly correlated with various physicochemical properties (firmness, color, and acid level) in LR-stage cherries. In DR-stage cherries, only firmness was positively correlated with soluble solid content. A positive correlation was found between soluble solid content and firmness of 200 randomly selected cherries. Thus, flesh firmness may be a useful quality factor indicating potential consumer acceptance of 'Bing' cherries.

• Korean Journal of Environmental Biology
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• v.18 no.3
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• pp.299-305
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• 2000

To determine the effects of underlayer vegetation on soil properties, the profiles, physical, and chemical properties of soil were investigated upon Fagus multinervis -Rumohra standishii, Fagus multinervis - typical, and Fagus multinervis -Sasa kurilensis subcommunities that was growing at Songinbong area of Ullungdo. There were little differences in soil profile properties among the three subcommunities. Also, there were little differences in physical and chemical properties of soil among the three subcommunities, except exchangeable Ca concentration in 0-10 cm soil depth. However, the soils of the study area in 0-10 cm soil depth comprised high organic matter and total N concentration as in an average value of 21.6% and 0.74%, respectively. Also, the soil showed very low bulk density and pH as in an average value of 0.43 g/㎤ and 4.4 in 0-10 cm soil depth, respectively. Due to the high soil organic matter and total N concentrations and the low bulk density and pH, the soil properties of Songinbong area are different from those of other forest in Korea.

• Korean Journal of Ecology and Environment
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• v.51 no.1
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• pp.29-39
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• 2018

Long-term variation of zooplankton community and species composition was studied from 2003 to 2014 in a deep reservoir, Lake Soyang, in monsoon climate region, Korea. In addition, we examined the correlation with environmental factors. Annual precipitation of watershed showed a large variation in the $705{\sim}1,779mm\;yr^{-1}$ and more than 70% of it was being concentrated from June to September. The water quality of Lake Soyang was shown a clearly seasonal variations and particularly turbid water flowing into the lake during rainy season was the most important environmental factors. Zooplankton community in Lake Soyang showed a significant difference before and after 2006. Zooplankton biomass has shown a large increase and also showed a change in the zooplankton community structure since 2006. The of zooplankton showed positive correlation with temperature and BOD, Chl. a, TP concentration. These results are considered that nutrient and organic matter contained in the turbid water influences the increase in zooplankton biomass and species composition. However, water quality was limited to account for the increase in biomass of zooplankton. For example, increase of small zooplankton density (rotifer; Keratella cochlearis, Polyarthra vulgaris) in spring which is dominated by diatoms (large size; Melosira, Synedra etc.) is considered as a bottom-up effect by the microbial loop. And increased density of crustaceans in autumn was considered a top-down effects by the relationship between predator and prey of microzooplankton and mesozooplankton. In other words the inflow of allochthonous organic matter during rainy season also affected to zooplankton food web in Lake Soyang. In conclusion, biomass, diversity and long-term variations of zooplankton in Lake Soyang were determined by physico-chemical factors but also it is considered that biological interactions is important.