• Title/Summary/Keyword: ecological sources

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Perception of Glare Source According to the Luminance Difference on a Window Plane (창면의 상하부 휘도차에 따른 글레어 광원의 인식변화)

  • Kim, Wonwoo;Kim, Jeong Tai
    • KIEAE Journal
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    • v.7 no.4
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    • pp.17-22
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    • 2007
  • The existing discomfort glare models are based on research that was conducted exclusively with uniform luminance sources. It is impossible to apply the models to windows of non-uniform luminance. For evaluating discomfort glare from windows, the method selecting glare source on a window plane is necessary. This study was carried outto propose a practical method to choose glare source from anon-uniform window plane. In the experiment, the perception of glare source according to the luminance difference is examined using a simulated windowof non-uniform luminance. The surface of the window is divided into two or three parts, and different luminance is setting on each surface. The observers were asked to decide whether the lower part of the window can be perceived as a glare source or not. The result shows that the lower part is perceived as a glare source when the lower part has over 37% of the luminance of the upper part of the window divided into two parts, and when it has over 51% of the luminance of the upper part of the window divided into three parts. the results may be applicable to select the glare source in awindow.

Combined Effects of PMV and Acoustics on Indoor Environmental Perception (PMV와 음환경의 복합 작용이 실내 환경 지각에 미치는 영향)

  • Yang, Wonyoung
    • KIEAE Journal
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    • v.16 no.6
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    • pp.135-142
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    • 2016
  • Purpose: The purposes of this paper are to investigate effects of indoor thermal environment on acoustical perception and effects of acoustics on indoor thermal perception, and to understand basic human perception on indoor environment. Method: Subjective assessment was performed in an indoor environmental chamber with 24 university students. Thermal conditions with PMV -1.53, 0.03, 1.53, 1.83 were simulated with a VRF system, a humidifier, a dehumidifier, and a ventilation system. Six noise sources - Cafe, Fan, Traffic, Birds, Music, Water- with sound levels of 45, 50, 55, 60 dBA were played for 2 minutes in random order. Temperature sensation, temperature preference, humidity sensation, humidity preference, noisiness, loudness, annoyance, and acoustic preference were assessed using bipolar visual analogue scales. The ANOVA and Turkey's post hoc test were used for data analysis. Result: Thermal environmental perceptions were not altered through 2 minutes noise exposure. Acoustical perceptions were altered by thermal conditions. The results were consistent with previous papers, however, the noise exposure time should be carefully considered for further development.

Litter Processing in Tropical Headwater Streams : Potential Importance of Palm Fruit Fall and Frond Fall

  • Covich, Alan P.
    • The Korean Journal of Ecology
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    • v.23 no.2
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    • pp.113-116
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    • 2000
  • Different phenological patterns of leaf and fruit fall among native and non-native riparian species provide a spatially and temporally heterogeneous series of alternative food resources for detritivores. Relatively little is known about qualitative differences among these different riparian species. Rates of litter inputs, decomposition, and retention for different sources of riparian litter require long-term documentation. Species of freshwater shrimps, crabs. insects. and gastropods are known to consume a wide range of litter inputs but how these dynamic food webs function under changing climatic and land-use conditions is unknown, especially in tropical streams. On-going studies in the Luquillo Experimental Forest. Puerto Rico provide an example of how inputs of fronds and fruits from palms (Prestoea montana) serve as important foods and microhabitat for species of freshwater crabs and shrimp. Native riparian species such as Prestoea montana are commonly distributed in the Luquillo Mountains especially along steep slopes and stream banks. After tropical storms with high winds, the large fronds from these native riparian trees provide important inputs of leaf litter to the stream food web. In some streams, the input of ripe fruit from non-native trees such as Java plum (Syzigium jambos) also provides a major source of detrital food resources, especially during periods when fruit fall from native species of palms may be limited.

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Effects of habitat conditions in created wetlands on sustaining wintering waterfowl in riverine plains, Nakdong River, South Korea

  • Choi, Jong-Yun;Jang, Ji-Deok;Jeong, Kwang-Seuk;Joo, Gea-Jae
    • Journal of Ecology and Environment
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    • v.38 no.3
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    • pp.343-352
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    • 2015
  • The landscape setting of a habitat strongly influences the distribution, abundance, and species composition of waterfowl. Thus, habitat assessment is very important to understand the habitat characteristics that sustain waterfowl assemblages. In this study, we hypothesized that the excessive use of artificial materials when new wetlands are constructed negatively influences wintering waterfowl. To test this hypothesis, we measured environmental factors, assessed habitat, and investigated waterfowl at 13 artificial wetlands in the Nakdong River Basin. There were greater numbers of waterfowl species and individuals in artificial wetlands with high habitat assessment scores. In contrast, environmental factors did not affect waterfowl distribution. In particular, features of natural habitats, such as macrophytes and sandbars, and the surrounding land-use patterns were important factors for sustaining waterfowl assemblages in each created wetland. Our results show that promoting naturalness in wetlands and surrounding areas would increase the species diversity and abundance of waterfowl. Further, complex habitats, such as wetlands and some terrestrial habitats, support both aquatic and terrestrial species because mixed habitats feature a larger array of food sources than more limited habitats do.

Emergy Evaluation of Korean Agriculture (한국 농업의 에머지 평가)

  • Kang, Daeseok
    • Journal of Environmental Science International
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    • v.26 no.9
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    • pp.1087-1099
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    • 2017
  • Emergy methodology was used to analyze the biophysical basis of Korean agriculture and assess its sustainablility. Total yearly emergy input into Korean agriculture was $7.72{\times}10^{22}sej/yr$ in 2013. Purchased inputs were the dominant emergy source, accounting for 90.1% ($6.95{\times}10^{22}sej/yr$) of the annual input. This clearly indicates that the Korean agriculture is a modern, industrialized system that depends mostly on market goods and services derived from nonrenewable resources. The monetary equivalent of the total emergy input was 18.9 trillion \/yr, 1.5 times greater than the total production cost from farm expense surveys. Emergy return on investment of Korean agriculture was low, with an emergy yield ratio of 1.11. Korean agriculture appears to exert pressure on the environment as revealed by the high environmental loading ratio of 9.30. With very low emergy input from renewable sources (9.7%) and high environmental pressure, Korean agriculture is not sustainable, with an emergy sustainability index of 0.12. This study suggests that higher use efficiency of and lower dependence on nonrenewable purchased inputs need to be prioritized in an effort to enhance the sustainability of Korean agriculture.

Biological Control Potential of Bacillus amyloliquefaciens KB3 Isolated from the Feces of Allomyrina dichotoma Larvae

  • Nam, Hyo-Song;Yang, Hyun-Ju;Oh, Byung Jun;Anderson, Anne J.;Kim, Young Cheol
    • The Plant Pathology Journal
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    • v.32 no.3
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    • pp.273-280
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    • 2016
  • Most biocontrol agents for plant diseases have been isolated from sources such as soils and plants. As an alternative source, we examined the feces of tertiary larvae of the herbivorous rhino beetle, Allomyrina dichotoma for presence of biocontrol-active microbes. The initial screen was performed to detect antifungal activity against two common fungal plant pathogens. The strain with strongest antifungal activity was identified as Bacillus amyloliquefaciens KB3. The inhibitory activity of this strain correlated with lipopeptide productions, including iturin A and surfactin. Production of these surfactants in the KB3 isolate varied with the culture phase and growth medium used. In planta biocontrol activities of cell-free culture filtrates of KB3 were similar to those of the commercial biocontrol agent, B. subtilis QST-713. These results support the presence of microbes with the potential to inhibit fungal growth, such as plant pathogens, in diverse ecological niches.

Effects of Experimental Drought on Soil CO2 Efflux in a Larix Kaempferi Stand

  • Kim, Beomjeong;Yun, Youngjo;Choi, Byoungkoo
    • Journal of Forest and Environmental Science
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    • v.34 no.3
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    • pp.253-257
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    • 2018
  • Climate models forecast more frequent and a longer period of drought events which may impact forest soil carbon dynamics, thereby altering the soil respiration (SR) rate. We examine the simulated drought effects on soil $CO_2$ effluxes from soil surface partitioning heterotrophic and autotrophic soil respiration sources. Three replicates of drought plots ($6{\times}6m$) were constructed with the same size of three control plots. We examined the relation between $CO_2$ and soil temperature and soil moisture, each being measured at a soil depth of 15 cm. We also compared which factor affected $CO_2$ efflux more under drought conditions. Total SR, autotrophic respiration (AR) and heterotrophic respiration (HR) were positively correlated with soil temperature (p < 0.05), and the relationships were stronger in roof plots than in control plots. Total SR, AR, and HR were negatively correlated only in roof plots, and the only HR showed a significant correlation (p < 0.05, r = -0.59). Soil respiration rates were more influenced by soil temperature than by soil moisture, and this relationship was more evident under drought conditions.

A Study on the Sustainable Development of Pusan Metropolitan City by the EMERGY Evaluation (EMERGY 평가에 의한 부산광역시의 지속적인 발전가능성 평가)

  • Son, Ji-Ho;Lee, Suk-Mo
    • Journal of Environmental Science International
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    • v.9 no.3
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    • pp.185-191
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    • 2000
  • Sustainable development has been the key concept, both in economic policies and in environmental management since 1970s. In the view of systems ecology, sustainable resource use strategies are considered to be essential in achieving sustainable development. During the last three decades, the discipline of systems ecology has applied ecological energetic analysis to the evaluation of the contribution of natural environments to economic systems. ENERGY analysis of main energy flows driving the economy of humans and life support systems of a city was made including environmental energies, fuel, and inputs, all expressed as solar emjoules. Total EMERGY use of Pusan was 3.89 E22 sej/yr, about 90 percent of it was purchased sources from outside during eleven years from 1985 to 1995. EMERGY flows from the environment were less than 10 percent. EMERGY yield ratio and environmental loading ratio were 1.10 and 10.45, respectively. EMERGY sustainability index is there(ore less than one, which is indicative of highly developed consumer oriented economies. Development of a city has been achieved in the short run by the economic growth, but it can be sustained in the long run by the use of renewable resource systems.

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An integrated approach to tropical and subtropical island conservation

  • Yamano, Hiroya;Satake, Kiyoshi;Inoue, Tomomi;Kadoya, Taku;Hayashi, Seiji;Kinjo, Koichi;Nakajima, Daisuke;Oguma, Hiroyuki;Ishiguro, Satoshi;Okagawa, Azusa;Suga, Shinsuke;Horie, Tetsuya;Nohara, Katsuhito;Fukayama, Naoko;Hibiki, Akira
    • Journal of Ecology and Environment
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    • v.38 no.2
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    • pp.271-279
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    • 2015
  • After the reversion of Okinawa (Ryukyu Islands) to Japan in 1972, extensive urban and agricultural development resulted in a significant increase in sediment discharge to coastal waters. The release of sediment has caused the degradation of freshwater and coastal ecosystems and biodiversity. A consideration for catchment-to-reef continua, as well as agricultural (socioeconomic) factors is necessary to establish proper land-based management plans for the conservation of the island environment. We have set up a framework to integrate biophysics and socioeconomics: 1) setting a conservation target and threshold, 2) identifying the sources and processes, and 3) examining cost-effectiveness and management priorities. The framework may be applicable to other tropical and subtropical islands with similar characteristics.

Ethics of Situated-ness, Sustainability and Ecology

  • Baek, Jin
    • Architectural research
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    • v.13 no.1
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    • pp.11-16
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    • 2011
  • This article illuminates the relationship between the human being and the surrounding things by referring to the philosophy of Martin Heidegger and Maurice Merleau-Ponty. Criticizing our habitual approaches to apprehending 'what a thing is,' the two thinkers elucidate how 'what a thing is' can be understood only in conjunction with situations in the everyday and how humanity is joined with the qualities of the thing. In addition to the situated-ness of a thing, this article demonstrates the situated-ness of the human being, too, by referring to the notion of the horizon in the tradition of phenomenology. The last part of the paper discusses the basic premises of sustainability in reference to the situated-ness of both things and human beings. Framing natural things such as light as the alternative sources of energy propagandized in sustainability seems progressive. However, this attitude maintains fundamentally the same instrumental attitude we had towards nature, an attitude that has caused the current ecological crisis. By pointing this out, this article seeks to shape a ground for a broad spectrum of sustainability that embraces non-instrumental dimensions such as the practical, the ethical and the spiritual. This article also points out the limits of some of the currently available versions of ecology such as Shallow Ecology and Deep Ecology. In so doing, it seeks to lay out the parameters that any future version of sustainability and ecology needs to address.