• Title/Summary/Keyword: Niche

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Analysis of Food Resources of 20 Endangered Fishes in Freshwater Ecosystems of South Korea using Non-metric Multidimensional Scaling and Network Analysis (비메트릭 다변량 척도법과 네트워크 분석을 통한 멸종위기 국내 담수어류 20종의 먹이원 분석)

  • Ji, Chang Woo;Lee, Dae-Seong;Lee, Da-Yeong;Park, Young-Seuk;Kwak, Ihn-Sil
    • Korean Journal of Ecology and Environment
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    • v.54 no.2
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    • pp.130-141
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    • 2021
  • By reviewing previous literature, we analyzed the food sources of 20 out of 29 endangered fish species from freshwater ecosystems in South Korea. A total of 19 studies reported that food sources of 20 endangered fish species included 20 phyla, 31 classes, 58 orders, 116 families, and 154 genera. Arthropod, insecta, diptera, and chironomidae were the most fed animal food sources according to different resolution of taxa index on phylum, class, order and family. Similarity, bacillariophyta, bacillariophyceae, naviculales, and cymbellaceae were the most fed abundant plant sources. A larger number of fish species were reliant on animal food sources than plant food sources. 18 of the endangered fish preyed on arthropods, whereas only 6 species consumed bacillariophyta. To characterize the feeding groups of the 20 fish species, a hierarchical clustering analysis and non-metric multidimensional scaling analysis were conducted. The fish species were divided into two groups: 1) insectivores and 2) planktivores. A network analysis, which associated the link between endangered fishes and food sources, also revealed the same two groups. The highest hub score of food sources was for macroinvertebrates, including diptera (0.47), ephemeroptera (0.42), and trichoptera (0.38), based on the network analysis. Niche breadth was used to calculate the diversity of the food sources. Phoxinus phoxinus (0.57) showed thehighest food source diversity among the fish species, whereas Iksookimia pacifica (0.01) showed the lowest. This study will be utilized for the conservation and restoration of the endangered fish species.

Changes in the Energy Landscape from Multi-Level Perspective: A Case Study of the Photovoltaic Module Carbon Certification System (다층적 관점에서 바라본 에너지경관의 변동: 태양광 모듈 탄소인증제를 사례로)

  • Jang, Geunyong
    • Journal of the Economic Geographical Society of Korea
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    • v.24 no.4
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    • pp.367-385
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    • 2021
  • This study examined changes in the energy landscape, focusing on the photovoltaic module carbon certification system. As the global photovoltaic market has been reorganized around Chinese companies, the South Korean government has pushed to strengthen the competitiveness of the nation's photovoltaic industry. However, a limitation remains in that the government-led effort was not sufficient to bring about dynamic changes in the energy landscape. Against this backdrop, this study explored the stages leading to the multi-level perspectives of "macro-environment, socio-technical regime, and niche" to track the process of the government and domestic photovoltaic companies as part of a socio-technical regime responding to global market changes. In particular, this study raised an issue with the conceptual discussion of multi-level perspective, which placed a particular emphasis on the rate of change at each level and the niche in which innovative experiments take place, and thus attempted to fill this gap by tracking the energy landscape that varies differently from space. These spatial discussions can track different carbon emissions coefficients and industrial characteristics for each country, and have a higher level of explanatory power for the system thus constructed. In addition, through discussions on the problems and implications of the government-led introduction of renewable energy policies, this study suggests the need to create and implement a field-oriented system.

Tree species migration to north and expansion in their habitat under future climate: an analysis of eight tree species Khyber Pakhtunkhwa, Pakistan

  • Muhammad Abdullah Durrani;Rohma Raza;Muhammad Shakil;Shakeel Sabir;Muhammad Danish
    • Journal of Ecology and Environment
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    • v.48 no.1
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    • pp.96-109
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    • 2024
  • Background: Khyber Pakhtunkhwa government initiated the Billion Tree Tsunami Afforestation Project including regeneration and afforestation approaches. An effort was made to assess the distribution characteristics of afforested species under present and future climatic scenarios using ecological niche modelling. For sustainable forest management, landscape ecology can play a significant role. A significant change in the potential distribution of tree species is expected globally with changing climate. Ecological niche modeling provides the valuable information about the current and future distribution of species that can play crucial role in deciding the potential sites for afforestation which can be used by government institutes for afforestation programs. In this context, the potential distribution of 8 tree species, Cedrus deodara, Dalbergia sissoo, Juglans regia, Pinus wallichiana, Eucalyptus camaldulensis, Senegalia modesta, Populus ciliata, and Vachellia nilotica was modeled. Results: Maxent species distribution model was used to predict current and future distribution of tree species using bioclimatic variables along with soil type and elevation. Future climate scenarios, shared socio-economic pathways (SSP)2-4.5 and SSP5-8.5 were considered for the years 2041-2060 and 2081-2100. The model predicted high risk of decreasing potential distribution under SSP2-4.5 and SSP5-8.5 climate change scenarios for years 2041-2060 and 2081-2100, respectively. Recent afforestation conservation sites of these 8 tree species do not fall within their predicted potential habitat for SSP2-4.5 and SSP5-8.5 climate scenarios. Conclusions: Each tree species responded independently in terms of its potential habitat to future climatic conditions. Cedrus deodara and P. ciliata are predicted to migrate to higher altitude towards north in present and future climate scenarios. Habitat of D. sissoo, P. wallichiana, J. regia, and V. nilotica is practiced to be declined in future climate scenarios. Eucalyptus camaldulensis is expected to be expanded its suitability area in future with eastward shift. Senegalia modesta habitat increased in the middle of the century but decreased afterwards in later half of the century. The changing and shifting forests create challenges for sustainable landscapes. Therefore, the study is an attempt to provide management tools for monitoring the climate change-driven shifting of forest landscapes.

Situation and Outlook of the U.S. Organic Produce and Foods (미국의 유기농식품 -현황과 전망)

  • Heo, Jang
    • Korean Journal of Organic Agriculture
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    • v.10 no.3
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    • pp.25-39
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    • 2002
  • This paper aims to provide quite recent information on the organic industry in the U.S. Major focuses are on the development of cultivation and marketing of fresh and processed organic produce and foods, newly enforced certification program, consumers' purchasing behaviors toward organic foods, and social survey results administered to the organic farmers in the U.S. The U.S. recorded 8 billion dollars' sale of organic foods in 2000, which was the largest in the world and showed 23% growth compared to the previous year. Yet the organic industry is still a niche market, occupying merely 1.5% of total food sale amount. The natural foods markets have not been so concentrated in the U.S., but it is changing and a few wholesale mart such as Whole Foods is emerging. Recent introduction of new certification program provide unified and sole standard at the federal level to which every certifier needs to adjust itself in order to be acceredited by the government. According to a social survey, consumers purchase organic foods because they concern about health, they stick to their own modes of life favoring natural foods, and so on. Another social survey shows that most organic farmers sell their produces to wholesalers, distributers, or producer coop, and direct sale to visitors at their own farm comprises of about 8 percent of their organic land.

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The Influences of Technological Innovation and Cost Management for Elevation of Small Enterprise Competitiveness on Productivity : Focused on Marine Engine Suppliers (중소기업 경쟁력 향상을 위한 기술혁신 및 원가관리가 생산성에 미치는 영향 : 선박엔진 부품제조업체를 중심으로)

  • Lee, Seol Bin;Baek, Dong Hyun
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.36 no.4
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    • pp.9-17
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    • 2013
  • The purpose of this study is to figure out the impacts of technological innovation and cost management on productivity in small shipping industries to come up with developmental implications. To achieve this, a survey was carried out to 150 workers in small shipbuilding industries through April 2 to April 20, 2012. As for findings stated above, technological innovation and cost management in the Korean small shipbuilding industries were key factors that elevate financial and non-financial productivity. In the light of low technological prowess and cost structure of small shipbuilding industries, their productivity can be improved when intensive cost management with production factor technology as know-how is realized through quality management, which product development technology is the top priority as an independent niche strategy. Consequently, the combination of infrastructures in small shipbuilding industries with continuous efforts for cost reduction by the link to the systematized structure can't only secure their independent competitiveness, but raise their productivity.

Microbial Fuel Cells: Recent Advances, Bacterial Communities and Application Beyond Electricity Generation

  • Kim, In-S.;Chae, Kyu-Jung;Choi, Mi-Jin;Verstraete, Willy
    • Environmental Engineering Research
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    • v.13 no.2
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    • pp.51-65
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    • 2008
  • The increasing demand for energy in the near future has created strong motivation for environmentally clean alternative energy resources. Microbial fuel cells (MFCs) have opened up new ways of utilizing renewable energy sources. MFCs are devices that convert the chemical energy in the organic compounds to electrical energy through microbial catalysis at the anode under anaerobic conditions, and the reduction of a terminal electron acceptor, most preferentially oxygen, at the cathode. Due to the rapid advances in MFC-based technology over the last decade, the currently achievable MFC power production has increased by several orders of magnitude, and niche applications have been extended into a variety of areas. Newly emerging concepts with alternative materials for electrodes and catalysts as well as innovative designs have made MFCs promising technologies. Aerobic bacteria can also be used as cathode catalysts. This is an encouraging finding because not only biofouling on the cathode is unavoidable in the prolonged-run MFCs but also noble catalysts can be substituted with aerobic bacteria. This article discusses some of the recent advances in MFCs with an emphasis on the performance, materials, microbial community structures and applications beyond electricity generation.

Issues and Trends concerning of Ecological Landscape Planning and Design with ESSD (지속 가능한 개발 및 생태조경분야의 연구경향과 과제)

  • 이명우
    • Journal of the Korean Institute of Landscape Architecture
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    • v.32 no.1
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    • pp.139-156
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    • 2004
  • All Papers on Ecological Landscape Degign in KILA from 1973 to 2003 are listed herein for finding research issues and trends. The emerging field of Ecological studies of landscape design is based on Landscape Ecology and Watershed Ecology, the Principles of which can be applied to surveying and evaluation, Planning and design, construction and management focusing preservation of wildlife habitat and niche. This field can be classified into six categories: 1. Sustainable site planning and index, 2. Ecological planning process and regulation, 3. landscape ecology and biotope map, 4. Watershed and eco corridor project, 5. Urban forestry and environment, and 6. artificial ground and restoration ecology. The following is the summary of the findings from Paper review: 1. Sustainable index shall be studied about more specified sites. Water recycling facilities, and reservation wet land need to be studied. 2. Policy and legislation research on Ecological design shall be researched by expanding of the application field. Nature park planning and management fields shall be considered as the main theme of green networking Parts. 3. Landscape Ecological studies should be connected to practical surveying data, e.g. the eco-maps published by Environment Ministry. Traditional culture and science should be joined with the modem science. 4. Eco-corridor planning will go with the scenarios and theories of watershed ecology. 5. Urban forestry shall be studied with the wildlife's behavior and habitat. 6. Restoration engineering techniques should be reconsidered with the wildlife's existence and environmental affiliation.

Factors Affecting the Usage of Elderly People's Smartphones: Based on UTAUT Model (고령자의 스마트폰 활용행동에 영향을 미치는 요인: 통합기술수용모델(UTAUT)을 중심으로)

  • Jang, Hyun-Yong;Koh, Joon
    • The Journal of Information Systems
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    • v.26 no.1
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    • pp.143-169
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    • 2017
  • Purpose With the increase of the elderly population, the growth of its information system related market is increasing. However, empirical studies for the usage of elderly people's smartphones are still limited. This study aims to investigate the factors that affect the seniors' smartphone usage behaviors. Design/Methodology/Approach First, a preliminary study was conducted with targeting seniors who have visited Gwangju Senior Technology Center(GSTC) in order to understand the factors that affect the intention of utilizing smartphones. Next, based on the preliminary study results and literature reviews including the UTAUT model, performance expectancy, effort expectancy and social influence were considered for the major factors affecting the usage of elderly people's smartphones. Also, the moderate effects of personal innovativeness and usage function were discussed. A questionnaire survey of 181 seniors visiting GSTC was analyzed to empirically test the research model. Findings By the empirical tests, the performance expectancy and the effort expectancy of the seniors had significant impacts on their smartphone usage behavior. While the moderating effect of personal innovativeness was not significant, the moderating effect of the usage function was significant in the relationship between performance expectancy and the smartphone usage behavior. The results of this study are expected to provide guidelines to excavate the technical development and the niche market targeting the elderly people.

Phenological Studies of Deciduous Trees in the Cool Temperate Region of Japan

  • Jun, Kala;Hayashi, Ichiroku
    • Journal of Ecology and Environment
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    • v.31 no.3
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    • pp.193-200
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    • 2008
  • We obtained quantitative information on leaf unfolding and leaf shedding by observing 45 species of cool temperate deciduous trees in an arboretum over 5 growing seasons. These trees were in leaf (the foliage period) for 207 days on average after 1 April; 50% of leaves had been shed by 192 days after 1 April. Duration from the start of leaf unfolding to 50% leaf shedding was 157 days on average. Leaf unfolding began 35 days on average after 1 April. For leaf unfolding to begin, a$ 51^{\circ}C{\cdot}day$ of cumulated daily mean air temperature above $5^{\circ}C$ from 1 January (modified Kira's warmth index) was needed. Fifty-nine days elapsed between initiation and the final stage of leaf unfolding. The period of net photosynthetic assimilation was 157 days. The species with succeeding- type leaf unfolding associated with the anemochore seed type dominated the early stage of succession, while the species with flush-type leaf unfolding tended to dominate the late stage of succession. Few species were found in regions where late frosts occur after the day when the cumulative temperature for leaf unfolding is achieved. Biological characteristics include time of leaf unfolding, which affects the life history of each species, so that each species occupies its own niche in the stand. We conclude that that leaf phenology, such as timing of leaf unfolding and leaf shedding, is one of the components of each species' ecological characteristics.

Development of All-in-One Pattern Specialized for Obesity in Old Age

  • Yun, Jeong;Na, Mi-Hyang
    • Fashion & Textile Research Journal
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    • v.21 no.6
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    • pp.830-836
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    • 2019
  • A diverse range of products are currently being sold; however, it is very difficult to purchase All-in-One patterns that reflect the body types of the elderly stage in the open market. This study is to develop specialized All-in-One patterns by assessing obese body types characteristics of the elderly social class. Five healthy women with typical obese body types in the elderly stage with busts, waists, and hips surpassing 100 cm were chose as test subjects. The three subjects for the wearing experiment are those with more than one year of experience wearing a bodysuit. A self-evaluation was made three times by looking in the mirror. The data from this study was processed to find averages and deviations; in addition, and a t-test was performed using the SPSS 24 statistical software. A total of 13 body parts were measured prior to and while wearing the specialized All-in-One patterns. Significant results were obtained from all 12 items. All-in-One for research appears to have produced a high level of satisfaction for subjects. This study can provide basic data on elevating the levels of satisfaction of the consumers in their elderly stages with special body types that deviate from standard body types at the time of wearing garments as well as for inner-wear companies to graft this market as a high-value-added niche market.