• 제목/요약/키워드: Ecological evolution

검색결과 151건 처리시간 0.024초

Comparison and analysis on sheep meat quality and flavor under pasture-based fattening contrast to intensive pasture-based feeding system

  • Zhang, Zhichao;Wang, Xiaoqi;Jin, Yan;Zhao, Kai;Duan, Ziyuan
    • Animal Bioscience
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    • 제35권7호
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    • pp.1069-1079
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    • 2022
  • Objective: The objective of this study was to investigate the effect of 4-month intensive feeding on the meat quality, fatty acid profile, flavor, and growth performance of grazing Hulunbuir sheep (HBS). Methods: The HBS were selected 4-months after birth in a pasture rearing system as the experimental animals (n = 44, female, average body weight 23.8±2.2 kg) then divided equally into pasture-based grazing fattening (PAS) and concentrate-included intensive fattening (CON) groups for another 4-month finishing. When finished fattening, all animals were slaughtered to collect musculus longissimus dorsi subcutaneous adipose tissue and to investigate the influences on meat quality, fatty acid profile, flavor and growth performance. Results: The results showed lambs in CON group got significantly higher live weight, hot carcass weight, and dressing percentage. The CON group had significantly higher value of redness (a*), lightness (L*) and water holding capacity (p<0.05), significantly lower value of Warner-Bratzler shear force than the PAS group (p<0.05). The subcutaneous fat from CON group lambs demonstrated a significantly higher content of C18:1 and C18:2 (p<0.05), but lower C14:0 and C16:0, indicating an increased degree of unsaturated fatty acid. The content of 4-methyloctanoic acid, 4-ethyloctanoic acid and 4-methylnonanoic acid had increased 2 to 4 times, representing a more intense odor in the CON group. However, the values were still lower than most sheep breeds reported, indicating the indoor feeding system could not fundamentally deteriorate the excellent meat characteristic of HBS. Conclusion: It was evident that lambs in CON group exhibited a better meat production performance, improved in meat color, texture and healthier fatty acid profile through pasture-weaned concentrate included intensive fattening system, which offers a good alternative regimen for lamb finishing and has a wide prospection in the HBS meat industry.

Geographic variation in the acoustic signals of black-billed magpies (Pica pica) in South Korea and Japan

  • Lee, Sang-Im;Lee, Sun-Hee;Nam, Hyun-Young;Choe, Jae-Chun
    • Journal of Ecology and Environment
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    • 제34권2호
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    • pp.167-174
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    • 2011
  • Black-billed magpies (Pica pica) are a highly sedentary species due to their short and round wings, which are not adequate for long distance flights. We investigated geographic variation in the vocal signals of magpies residing in South Korea and Japan (subspecies sericea). Based on the magpie's limited dispersal ability, we predicted that the variation in vocal signals of black-billed magpies could be explained by geographic barriers such as mountain ranges and straits. We analyzed four-syllable chatter calls of magpies from five localities in South Korea, which are separated by mountain ranges (Seoul, Daejeon, Daegu, Gwangju, and Busan), and two island localities separated from the mainland by straits (Jeju in Korea and Saga in Japan). We found significant differences in the characteristics of magpie chatter calls recorded in the seven localities, and the variation pattern was independent among the variables. Mainland-island differentiation and north-south differentiation were observed. In general, magpies on Saga were the most distinctive. North-south differentiation was observed among the Korean mainland localities. However, the pattern was not related to the presence of putative geographic barriers. We hypothesize that the patterns of geographic variation in the structure of magpie chatter calls residing in South Korea might have been shaped by a sudden expansion of magpies followed by low level of local isolation, which may have led to vocal differentiation. Along with elucidating the vocal environment of Korean magpie populations, more extensive sampling is needed to clarify the functional aspects of geographic variation in the vocal signals of Korean magpies.

환경 소양 개념의 변천과 환경 소양 측정 연구 (A Study on the Conceptual Evolution of Environmental Literacy and Its Assessment)

  • 진옥화;최돈형
    • 한국환경교육학회지:환경교육
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    • 제18권2호
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    • pp.31-43
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    • 2005
  • In this study, after establishing assessment framework and reviewing the conceptual evolution and component of EL(Environmental Literacy) through literature review, through middle school students as population, the level of EL and relationship of its related variables were examined. The investigation was consisted of second and third grades of urban and rural middle schools in Choongbook. The used measurement methods were objective evaluation and Likert-type scale. The questionnaire instrument variables were consisted of 80 items on environmental literacy variables and six items on student gender, area of residence, environmental lesson, degree of environmental concern, environmental information, environmental activity as background variables. The major findings of this study were as follows: 1. Although the broad and obscure concept of EL has been evolved until 1992, it has been developed more systematic and precise after 1992. But there is not still an agreed concept. 2. The subordinate components of EL were consisted of cognitive, affective, and behavioral aspects. Both ecological knowledge(KEOC) and environmental skill(SKILL) were determined to serve as two powerful predictors of EL. 3. The level of EL of middle school student was showed statistically significant difference to some variables by student gender, residential area, environmental lesson, environmental concern, environmental information, and environmental activity variables. And the most influential variables of EL in middle school student were environmental skill(SKILL), and locus of control (LOC). Based on the findings of this study, the following suggestions are drawn: It should be established a precise concept on EL as the ultimate aim of environmental education both interdisciplinary cooperation and experts of environmental education and also performed further longitudinal study which assessed multidimensional variables which are able to exactly measure the EL of middle school student.

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Male Mating Strategies through Manipulation of Female-perceived Predation Risk: A Minireview and a Hypothesis

  • Han, Chang-S.;Jablonski, Piotr G.
    • Journal of Ecology and Environment
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    • 제31권1호
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    • pp.1-7
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    • 2008
  • In this minireview we focus on how males may exploit female's sensitivity to predation risk in the context of mating. It has been shown in studies on guppies and jumping spiders that in response to altered female behaviors, which are adaptations to the unfavorable environment and a consequence of females' higher sensitivity to predator's presence as well as females' higher predation risk, males can adopt condition-dependent mating tactics. It appears that in such cases males do not modify their reproductive behavior directly in response to their own perception of predation risk, but indirectly in response to changes in female behavior induced by predator presence. It has also been recently shown in crabs that males can exploit female behavior by creating safer habitat spots, which increases the male mating success. Hence all the evidence suggests that males not only respond to female sensitivity to the natural variation in predation risk, but that males can also exploit female behavior by altering the environment. As a logical extension of these findings, we present a hypothesis that in certain conditions males can manipulate the environment in order to increase the predation risk and to induce female behaviors that enhance the male's mating success with the increased predation risk. We propose that such a manipulation to increase predation risk is expected to evolve in males of species with a strong sexual conflict and female-biased predation risk. Although empirical evidence has not been yet shown, initial observations in a water strider species in Korea, Gerris gracilicornis, seem to support this hypothesis.

생태계 관점에서의 문화콘텐츠 산업 구성 및 구조 (Ecosystem Configuration and its Structure of Cultural Contents)

  • 류준호;윤승금
    • 한국콘텐츠학회논문지
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    • 제10권4호
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    • pp.327-339
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    • 2010
  • 문화콘텐츠는 본래 다양한 콘텐츠 생산자와 유통 소비에 이르는 사이클을 가지고 있는 분야이다. 이러한 사이클 안에는 문화콘텐츠 생태계를 구성하는 다양한 개체 요소들이 포함되어 있고 이들 개체들 간의 조화로운 관계의 모색이 중요한 이슈가 되고 있다. 문화콘텐츠분야에 대한 생태계적 관점의 접근은 최근 관심의 확대는 물론 관점 적용에서 오는 유용성에도 불구하고 본격적으로 시도되지 않은 분야이며, 따라서 문화콘텐츠 생태계를 구성하고 있는 개체 요소의 미확인은 물론 개체간의 상호 작용 원리, 개체별 발전 방안, 생태계를 구성하고 있는 모든 개체의 공통적 발전을 이루는 공진화의 원리 등 생태계 내부 및 그 작용에 대한 구체적인 논의가 없는 상태이다. 때문에 본 연구에서는 생태계와 사회과학의 제 분야에서 연구되어 온 생태계 모델을 통해 문화콘텐츠 생태계를 구성하고 있는 개체 요소의 확인, 그리고 각 개체들간의 상호 작용 및 개체 각각은 물론 전체 생태계의 발전 방향에 대해 모색해 보고자 한다.

진화론적 관점의 기술혁신의 동태성: 정보기술산업과 조직경쟁유형의 진화 (Technological Change and Organizational Strategy as an Evolutionary Process)

  • 차대규
    • 산학경영연구
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    • 제11권
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    • pp.15-38
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    • 1998
  • 본 연구는 급진적인 환경면화를 대표하는 정보산업에서의 기술혁신의 진화과정을 탐색하였다. 진화론경제학이론을 바탕으로하는 동태적인 기술변화과정과 조직생태학이론으로부터의 산업-특정조직유형간의 관계를 결합하는 통합적인 모델을 개발하였다. 진화론경제학이론의 관점에 기초하여, 시감이 감에 따라 선택압력에 의해 미래기술의 지표로서 역할을 하는 소위 '기본설계'가 등장하고 그 기본설계는 일관성 있는 경로를 따르는 경향이 있으며, 그 기술이 한계점에 도달하기 전까지 기술경계들의 급진적 팽창을 촉진시키지만, 한계점에 도달했을 때 새로운 기술패러다임을 탐색한다는 것을 분석하였다. 아울러 조직군생태학 관점으로부터 5개 조직유형을 구분하였으며, 각 조직유형들은 산업내 기술변화의 진화과정에 따라 서로 다른 기회를 탐색한다는 것을 살펴보았다. 진화론경제학이론과 조직군생태학이론은 오랜 학문적 역사를 가진 생물학에 바탕을 두고 있으며 기존 전략 조직이론들이 설명하지 못했던 기술적 변화 또는 실패와 같은 전략적 사건들에 대한 인과관계를 설명하는데 깊은 통찰력을 제공해 준다. 따라서 향후 두 이론에 바탕을 둔 좀더 정교하고 통합적인 이론연구와 실증연구들이 지속될 필요가 있음을 말해준다.

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유비쿼터스 사회에서 나타나는 현대 공간에 관한 연구 - 인터렉티브 공간을 중심으로 - (A Study on contemporary space in Ubiquitous society - Focusing on Interactive space -)

  • 고귀한
    • 한국실내디자인학회논문집
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    • 제21권3호
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    • pp.50-57
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    • 2012
  • In Ubiquitous era. architecture is not the old building adapting ubiquitous technology. In order to take the role as new architectural paradigm in space, environment and technology, it has to develop technology continuously and experimental architecture at the same time. it must have co-evolution of architectural field and others through organic network. by that, the evolution of space will be in the way that combines space which is responded to human emotion and user-centric human-friendly. It will be the new paradigm of Ubiquitous digital space. Digital technology resulted in a change to a society as well as to the life of human and its way of thinking. Due to those changes, new terms or concepts come out and a new meaning is added to the conventional concepts. This aims to examine type of spatial contexts for interaction design experience. This study is performed through Literature research for theory by interactive space and case studies for construction elements to design. The range of case study is limited to interaction space in addition of interactive elements and user interface. And analysis conclusion is show the many type, First, Interactive space has special purpose for make a interaction by intelligent elements.(sensor, program, algorithm, New-technology) Second, Interactive space was cooperation with various professional for space purpose. Third. Interactive space is self-develop by algorithm, program, sensor network and that is harmonize with user. finally. Interaction space is show the temper elements about allness, metastatic, activeness, liquidity, relationship. That was written by ecological theory.

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Influence of microenvironment on the spatial distribution of Himantormia lugubris (Parmeliaceae) in ASPA No. 171, maritime Antarctic

  • Choi, Seung Ho;Kim, Seok Cheol;Hong, Soon Gyu;Lee, Kyu Song
    • Journal of Ecology and Environment
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    • 제38권4호
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    • pp.493-503
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    • 2015
  • This study analyzed how spatial distribution of Himantormia lugubris is affected by the microenvironment in the Antarctic Specially Protected Area (ASPA) No. 171 located in the Barton Peninsula of King George Island that belongs to the maritime Antarctic. In order to determine the population structure of H. lugubris growing in Baekje Hill within ASPA No. 171, we counted the individuals of different size groups after dividing the population into 5 growth stages according to mean diameter as follows: ≤ 1 cm, 1-3 cm, 3-5 cm, 5-10 cm, and ≥ 10 cm. The count of H. lugubris individuals in each growth stage was converted into its percentage with respect to the entire population, which yielded the finding that stages 1 through 5 accounted for 32.8%, 25.3%, 15.9%, 22.5%, and 3.5%, respectively. This suggests that the population of H. lugubris in ASPA No. 171 has a stable reverse J-shaped population structure, with the younger individuals outnumbering mature ones. The mean density of H. lugubris was 17.6/0.25 m2, mean canopy cover 13.3%, and the mean dry weight 37.8 g/0.25 m2. It began to produce spore in the sizes over 3 cm, and most individuals measuring 5-10 cm were adults with sexually mature apothecia. The spatial distribution of H. lugubris was highly heterogeneous. The major factors influencing its distribution and performance were found to be the period covered by snow, wind direction, moisture, size of the substrate, and canopy cover of Usnea spp. Based on these factors, we constructed a prediction model for estimating the spatial distribution of H. lugubris. Conclusively, the major factors for the spatial distribution of H. lugubris were snow, wind, substrate and the competition with Usnea spp. These results are important for understanding of the distribution in the maritime Antarctic and evolution of H. lugubris that claims a unique life history and ecological niche.

First Record of Six Marine Ciliate Species of Genus Strombidium (Ciliophora: Spirotricha: Oligotrichia) from Korea with Ecological Notes

  • Lee, Eun-Sun;Xu, Dapeng;Shin, Mann-Kyoon;Kim, Young-Ok
    • Animal Systematics, Evolution and Diversity
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    • 제28권3호
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    • pp.192-207
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    • 2012
  • To supply the morphological and ecological information of oligotrich ciliates in Korea, water samples were seasonally collected in Gwangyang Bay and Jinhae Bay from August, 2010 to February, 2012 and processed by quantitative protargol staining method. As a result, six species belonging to the genus Strombidium Clapar$\grave{e}$de and Lachmann, 1859 are identified: Strombidium emergens Kahl, 1932; S. dalum Lynn et al., 1988; S. epidemum Lynn et al., 1988; S. tressum Lynn et al., 1988; S. bilobum Lynn and Gilron, 1993; S. pollostomum Lynn and Gilron, 1993. These six species were newly reported from Korean coastal waters. Strombidium emergens is a middle sized Strombidium ($20-50{\mu}m$ in length) and has open and deep oral groove to girdle portion. Strombidium dalum is a small sized Strombidium (${\geq}20{\mu}m$ in length), that has torch-like spiral anterior membranelles and an inverted triangles-shaped macronucleus on the posterior pole. The small sized S. epidemum has conspicuous trichites surrounding the girdle portion and ventral membranelles distinctly separated from anterior membranelles. The small sized S. tressum has torch-like spiral and extremely long trichites among the cilia of anterior membranelles. The middle sized S. bilobum has a bilobed macronucleus. Strombidium pollostomum is also a small sized Strombidium but its ventral membranelles are continuously connected with anterior membranelles. The five species except S. emergens occurred frequently over the wide range of water temperatures and salinities.

태안반도 하계 해조상 및 군집구조 (Summer Marine Algal Floras and Community Structures in Taean Peninsula, Korea)

  • 유현일;이지희;이기훈;백상흠;허영범;노형수;최한길
    • 한국수산과학회지
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    • 제40권4호
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    • pp.210-219
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    • 2007
  • The benthic marine algal flora and community structure were examined at five sites of the Taean Peninsula, Korea, during July-August 2005. Ninety-six algal species were Identified, including 14 green, 21 brown, and 60 red algae, and 1 marine plant. The common species that occurred at the five sites were Sargassum thunbergii, Gelidium divaricatum, Caulacanthus okamurae, Gracilavia vermiculophylla, and Neorhodomela aculeata. Sthunbergii was the dominant species in terms of coverage and biomass at ail of the study sites. The average biomass varied from $23.72g/m^2$ in dry weight at Chaeseokpo to $66.43g/m^2$ at Padori. The species could be divided into six functional groups in terms of morphological characteristics: 41 coarsely branched forms, 25 filamentous forms, 16 sheet forms, 7 thick leathery forms, including the marine plant Phyllospadix iwatensis, 4 crustose forms, and 3 Jointed calcareous forms. The seaweed communities at the five study sites were unstable and the environmental conditions were bad or very bad. Among the five study sites, the ecological evaluation index (EEI) and diversity index (H') were maximal at Padori at 2.29 and 1.98, respectively. By contrast, the dominance index (DI) was minimal at Padori (0.55) and maximal at Baramarae (0.96). Therefore, we conclude that the rocky shore at Padori has the best environment among the five study sites, although the species richness and biomass of seaweeds have declined continuously over the last 10 years.