• Korean Journal of Environmental Biology
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• v.26 no.4
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• pp.385-391
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• 2008

In Korea, Quercus acutissima distributed in good condition with high nutrients and moisture content, but Quercus variabilis in dry soil or rock habitate. In order to understand this ecological distribution of Q. acutissima and Q. variabilis, we cultivated the seedlings of two oak species treated with light, soil moisture and nutrient gradients each four level, from May to October in glass house. Then we measured the ecological niche breadth and niche overlap of the two species, and analyzed the relationship of competition using cluster analysis and PCA ordination. Ecological niche breadths of Q. acutissima under moisture and nutrient treatments were slightly wider than those under light one. Among 14 characters measured, 6 characters related with length items were wider in all the environmental treatments, but 8 characters connected with weight terms narrower in light treatment. Ecological niche breadths of Q. variabilis under moisture and nutrient treatment were wider than those of light one. Ecological niche of Q. acutissima was wider than those of Q. variabilis in all the environmental treatments. Ecological overlap between two species was higher with a range of 0.87$\sim$0.92, especially higher in soil moisture factor. These results means that Q. acutissima is more competitive than Q. variabilis, especially in soil moisture condition. Two species were ordinated with distinct group based on 9 characters. From these results, it can be explained that what Q. variabilis distributed in bad soil condition is due to the escape strategy, because of its low competitive ability to Q. acutissima in natural communities.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.1
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• pp.72-82
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• 2014

This study was conducted to predict the changes of yearly productive area distribution for pinus densiflora under climate change scenario. For this, site index equations by ecoprovinces were first developed using environmental factors. Using the large data set from both a digital forest site map and a climatic map, a total of 48 environmental factors including 19 climatic variables were regressed on site index to develop site index equations. Two climate change scenarios, RCP 4.5 and RCP 8.5, were then applied to the developed site index equations and the distribution of productive areas for pinus densiflora were predicted from 2020 to 2100 years in 10-year intervals. The results from this study show that the distribution of productive areas for pinus densiflora generally decreases as time passes. It was also found that the productive area distribution of Pinus densiflora is different over time under two climate change scenarios. The RCP 8.5 which is more extreme climate change scenario showed much more decreased distribution of productive areas than the RCP 4.5. It is expected that the study results on the amount and distribution of productive areas over time for pinus densiflora under climate change scenarios could provide valuable information necessary for the policies of suitable species on a site.

• Journal of The Korean Association For Science Education
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• v.31 no.4
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• pp.513-527
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• 2011

There have been studies about conceptual ecology making a profound study of conceptual changes in learners' cognitive structure. Because learners' cognitive structure have been compared to ecology, it is natural to think that conception in learner's cognitive structure have a niche as species in ecology have niches. Therefore, it is necessary to study niche approach about conception that learners recognize in their cognitive structure. The purposes of this study were to identify relationships among conceptions that 5th grade elementary school students recognize about photosynthesis and to identify how these relationships among conceptions about photosynthesis change before and after a class of photosynthesis in curriculum in terms of an approach of ecological niche which are composed of 3 domains - diversity of conceptions, relevance and frequency rate of conceptions, and competition among conceptions. Open ended questionnaire was developed by 4 fields: photosynthetic place, photosynthetic products, photosynthetic materials needed and environment factors of photosynthesis. The subjects sampled in this study were 310 5th grade elementary students in 5 cites. Before and after classes in photosynthesis in science curriculum, students were asked to write down conceptions that they knew about the 4 fields of photosynthesis of questionnaire and to write down scales of relevance from 1 to 30 about how they think the conceptions are related to the field of photosynthesis. The results of this study showed the following: First, most students have had a variety of conceptions and commonly recognized 'light' and 'water' as concepts in photosynthesis. Second, students still recognized their preconceptions like 'soil' and 'root,' etc. that were far from scientific conceptions of photosynthesis although they took classes in photosynthesis. Third, students needed to take the various strategies of teachers because they did not recognized scientific conceptions appropriately about photosynthetic fields. Fourth, it appeared that photosynthetic conceptions recognized by students had status in terms of relevance and frequency rate of conceptions, and competition among conceptions, and that they looked like the niche of conceptions in their conceptual ecologies.

• Journal of Wetlands Research
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• v.25 no.3
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• pp.196-204
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• 2023

Eleutherococcus gracilistylus is a designated rare plant by the Korea Forest Service, a deciduous broad leaf shrub native to the Gotjawal region, Jejudo. This study aimed to analyze the growth responses of E. gracilistylus to three environment factors such as light, moisture, and organic matter, and measure its ecological niche breadth. Based on these results, an attempt was made to identify suitable environmental conditions. E. gracilistylus exhibited increased above-ground length, leaf area, and plant leaf weight under intermediate conditions of light availability(L3, 50% of natural light), rather than very high or very low light conditions. Moisture availability and organic matter availability showed variations in growth responses in terms of leaf count and plant leaf weight. Under moisture availability, growth was favorable under or below intermediate conditions (M3, 240ml), while under organic matter availability, growth response was better above intermediate conditions (N3, 12%). Ecological niche breadth showed in the light factor(0.951), the moisture factor(0.977), and the organic matter content one(0.964). These results indicate that the preferred habitat of E. gracilistylus is somewhat shady, slightly dry, and has a lot of nutrients, and that the environmental factor that has the greatest impact on growth is the amount of light, which is considered to be a priority consideration for habitat management in its native area.

• Information and Communications Magazine
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• v.29 no.10
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• pp.3-8
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• 2012

본고에서는 스마트폰과 스마트TV 등과 같은 커넥티드 디바이스(connected device)에 관한 ICT 생태계(이하 '스마트 미디어 생태계')에 대해 알아본다. 스마트 미디어 생태계는 플랫폼을 중심으로 가치가 창출되는 생태계라는 특징을 가진다. 특히, 양면시장(two-sided market)에서 관찰되는 직/간접적 네트워크 외부성(direct and indirect network externality)에 의해 작동된다. 또한 단일 기능요소보다는 여러 사업자로부터 제공되는 기능요소들의 복합체인 플랫폼 연합체(platform coalition)로 출발한다. 이에 따라 생태계 초기에는 생태계 간 경쟁과 더불어 생태계 내에서 메타 플랫폼(meta platform)의 지위를 획득하려는 지배구조 경쟁도 전개된다. 스마트 미디어 생태계의 특성과 진화과정 및 운영원리에 대한 이해는 생태계 참여자들의 전략과 생태계 활성화를 위한 정책방향에 시사하는 바가 크다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.499-500
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• 2001

곰피(Ecklonia stolonofera)는 한국 동, 남해안에 널리 분포하는 다년생 해조로서 일반적으로 조하대의 수심 2-l0m깊이에 서시한다. 이종은 해중림을 구성하는 해조로서 천해의 주요한 1차 생산자일 뿐만 아니라 연안생태계에서 수산물생산에 직접 관여하는 중요한 생태적 지위를 가진다. 곰피의 생태 및 생리에 대해서는 Notoya와 Aruga (1990)의 보고가 있으며 이외에 유주자낭 형성(Notoya 와 Asuke, 1983)에 관한 것과 유아포체내의 핵분열 (Yabu and Notoya, 1985)에 관한 연구가 있고 국내에서는 부산만의 저조선 부근에서 곰피의 연령과 성장에 관하여 한 Park 등 (1994)의 연구가 있다. (중략)

• 월간낙농육우
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• v.35 no.11
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• pp.139-143
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• 2015

산지생태축산은 환경 친화적인 순환형의 생산방식으로 안전하고 맛있는 유기식품 등 많은 장점이 있어, 과소화, 황폐화가 진행되는 중산간지역을 활성화시키기 위한 기폭제로서 많은 기대를 받고 있다. 그러나 앞에서 기술한 바와 같이 기술적 문제에 더해 사회적, 경제적인 많은 저해 요인이 산지생태축산의 보급과 정착을 방해하고 있다. 이와 같은 과제를 극복하기 위해서는 생산자 혹은 관계단체의 노력에는 한계가 있으니 국가와 지역행정의 지원이 강화되어야 하는 것은 물론 지역주민과 소비자를 끌어들인 종합적인 지원책에 대해 검토할 필요가 있다. 산지생태축산은 21세기의 한국축산에 확고한 지위를 차지한 농법으로 중산간지역 농업의 견인차가 될 농법이다. 산지생태축산을 활성화 하기 위해서는 실효성 있는 지원책을 과감히 강구하며 다양한 제약을 극복할 방안 역시 선구적으로 마련해야 한다. 기존의 제도가 시대적으로 뒤쳐진다는 결함이 있었다면 이것을 감수해가면서 극복하는 것이 아니라 제도 개선을 하는 일이 더 중요하다. 국가나 도단위의 지역은 종래의 발상을 넘은 지역의 대처에 제동을 거는 일 없이 오히려 선구적인 시읍면의 활동을 전력으로 지원하는 자세를 가져야 한다. 그래야만 새로운 식품 농업 농촌을 고려한 창조적 농정의 실현으로 진정한 6차산업을 구현할 수 있다.

• Journal of Science Education
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• v.41 no.2
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• pp.195-212
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• 2017

Small group learning is an educational approach to allow students to solve the problems and to achieve a common goal. Especially, small group learning in science education is one of the most important educational approaches and effective to ensure understanding of a topic. Small group learning consisting of three students in science education maximize student understanding and learning efficiency. However, It is reported that the effects of small group learning on achievement show different results, corresponding to different grouping methods(homogeneous/heterogeneous). This study investigated the effects of grouping method on difference of ecological niche of photosynthesis concepts. To achieve this, 1107 7th students were composed of homogeneous and heterogeneous groups classified into top, middle, and bottom levels. The photosynthesis units were divided into four categories: the photosynthesizing place, the substances of photosynthesis, required materials for the photosynthesizing, and environmental factors affecting photosynthesis. A questionnaire was composed by selecting concepts having a frequency of 4% or more based on prior studies on the change of the ecological status of photosynthesis. The questionnaire was scored in terms of relativity and understanding on each of the proposed concepts in the four categories. The result of this study is as set forth below. 1) There was an enhancement of learning the concept of science in small group classes consisting of 3 students. 2) To enhance the average upon composing of a group, it is proposed that the group should be formed homogeneously, and to reduce the deviation between the members, it is proposed that the group should be formed heterogeneously. Through this study, it is expected that specific studies verifying the difference or effect on the duplicity of results are conducted based on the composition of groups.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.317-323
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• 2012

Fragmented urban forests, as green islands within urban area, are the primary habitats for a vast number of different organisms inhabiting large cities. The areas of the urban forests are usually small, and hence, the proportion of the forest edge is relatively high. It is therefore expected that overall butterfly diversity may be lower than that of suburban or rural forests, and that those of grassland species, forest edge species, and generalist species with a wider niche breadth may be richer. Butterflies were surveyed weekly by the line transact method in order to characterize the butterfly community of the Hongneung Forest, a fragmented urban forest in Seoul. Butterfly richness of the study forest is much lower than those of main forests around or in Seoul. Grassland species, forest edge species, and generalist species were found to be richer, which was in agreement with the expected patterns of urban butterfly communities. Also, an endangered species, Spindasis takanonis, was observed in the Hongneung Forest, showing that urban forests play important roles for conservation of rare species.

• Journal of Wetlands Research
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• v.25 no.2
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• pp.159-165
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• 2023

This study measured the ecological niche overlap between two deciduous oak species(Quercus acutissmia and Q. dentata) according to the change in growth responses after treating with the moisture and nutrient contents of the soil at four gradients, and interpreted the degree of competition between the two oak species by ordination method. In the moisture environment gradient, the ecological niche overlap of the two species was high in the photosynthesis-related leaf organs and low in plant architecture such as shoot length. In addition, in case of competition between two oaks, Q. dentata was remarkably dominant in soil moisture gradient, but Q. acutissimia slightly was slightly advantageous over Q. dentata in the soil nutrient gradient. These results show that even in a similar taxonomical group growing in a similar habitat, the response to the organ system of the plant varies depending on the type of environment factor, resulting in different competitive differences among plants.