• 제목/요약/키워드: disturbance ecology

검색결과 344건 처리시간 0.022초

묵밭에서 교란처리구배에 따른 중간교란가설의 검증 (Test of Intermediate Disturbance Hypothesis by Experimental disturbance Gradient in Old-Field Plant Community)

  • 이규송;김준호
    • The Korean Journal of Ecology
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    • 제21권3호
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    • pp.233-241
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    • 1998
  • In order to test of intermediate disturbance hypothesis that an intermediate level of disturbance maximize biodiversity and to elucidate the effect of disturbance during the early old-field succession, the response of plant community along an experimental disturbance gradient was investigated in a five-year old-field. Response of plant community along an experimental disturbance gradient was connected with light condition because artificial disturbance gradient had been treat by clipping of plants and removing of litter. Artificial disturbance in five-year old-field plant community retarded rate of succession by increasing invasion and performance of the earlier successional species in the initial and middle stage of disturbance treatment. The species richness in the blocks of intermediate disturbance level showed the peak in early and mid-summer. This result did correspond with the prediction of intermediate disturbance hypothesis.

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Study on Environmental Risk Assessment for Potential Effect of Genetically Modified Nicotiana benthamiana Expressing ZGMMV Coat Protein Gene

  • Kim, Tae-Sung;Yu, Min-Su;Koh, Kong-Suk;Oh, Kyoung-Hee;Ahn, Hong-Il;Ryu, Ki-Hyun
    • The Plant Pathology Journal
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    • 제22권4호
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    • pp.353-359
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    • 2006
  • Transgenic Nicotiana benthamiana plants harboring the coat protein(CP) gene of Zucchini green mottle mosaic virus(ZGMMV) were chosen as a model host for the environmental risk assessment of genetically modified plants with virus resistance. This study was focused on whether new virus type may arise during serial inoculation of one point CP mutant of ZGMMV on the transgenic plants. In vitro transcripts derived from the non-functional CP mutant were inoculated onto the virus-tolerant and -susceptible transgenic N. benthamiana plants. Any notable viral symptoms that could arise on the inoculated transgenic host plants were not detected, even though the inoculation experiment was repeated a total of ten times. This result suggests that potential risk associated with the CP-expressiing transgenic plants may not be significant. However, cautions must be taken as it does not guarantee environmental safety of these CP-mediated virus-resistant plants, considering the limited number of the transgenic plants tested in this study. Further study at a larger scale is needed to evaluate the environmental risk that might be associated with the CP-mediated virus resistant plant.

Ecological resilience of soil oribatid mite communities after the fire disturbance

  • Kim, Ji Won;Jung, Chuleui
    • Journal of Ecology and Environment
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    • 제36권2호
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    • pp.117-123
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    • 2013
  • This study investigated the impact of the fire disturbance and the pattern of recovery of soil dwelling oribatid mite communities with respect to the resilience from the fire disturbance. Oribatid mites are important decomposer animals of plant debris in soil with the feeding habits of saprophagy and mycophagy. Massive wild fire reduced soil oribatid mite abundance and diversity. The impact varied relative to the intensity of the disturbance. The proportion of the species common to the non-disturbed natural site increased as the time after the disturbance elapsed, which implying some degree of naturalness occurring in reorganization phase of the oribatid mite community. From the sites with different degree of fire impact, we found higher diversity in intermediately disturbed sites than in severely disturbed or non-disturbed site, supporting the intermediate disturbance hypothesis. Also this study showed that with differential degree of disturbance plots, resilience pattern after the disturbance can be explored even with shorter period research relative to the ecological succession of community.

Recolonization of benthic macroinvertebrates after anthropogenic disturbance in natural streams, South Korea

  • Chun, Seung-Phil;Chon, Seung-Hoon;Lee, Seung-Oh;Im, Jang-Hyuk;Lee, Woo-Kyun;Kim, Myoung-Chul
    • 한국환경생태학회지
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    • 제29권2호
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    • pp.228-235
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    • 2015
  • Stream ecosystems are closely related to many human activities. Therefore, streams are affected by anthropogenic disturbances such as riverine development and gravel-mining as well as deterioration of water quality. The goal of this study was to elucidate the recolonization process of the macroinvertebrate community after a small-scale anthropogenic disturbance. Field studies were conducted at three sites in a natural stream. The number of recolonizing species tended to increase slightly over time, exceeding the total species number of the control. Ephemeroptera contributed the most to shaping the recolonizing pattern of the entire community. From the result of changes in dominant species, the early recolonizers of each site were the species that showed more frequent occurrence particulary at each sites. But the late recolonizers are Chironomidae at all the sites commonly. This result implies that the actual differences exist among the recolonizing trends of each benthic macroinvertebrate taxon. Collector-gatherers and scrapers comprised about 70% of the recolonizing species. These results indicate that the recolonizing process of an aquatic community after an artificial disturbance depends on the environmental conditions(particularly substratum composition or organic pollution) of the habitat.

Composition and Structure of Himalayan Oak (Quercus leucotrichophora A. Camus) Forest under Various Degrees of Disturbance

  • Prasad, Sunil;Uniyal, Pooja;Chauhan, D.S.
    • Journal of Forest and Environmental Science
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    • 제31권1호
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    • pp.7-13
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    • 2015
  • Forest disturbance sometime considered as a tool of management as it believed that mid level disturbance constructs better micro-climatic conditions which ultimately boost up the plant diversity. The effect of different levels of disturbance on species composition and regeneration is very important. Present attempt was carried out in a temperate evergreen oak forest which was under various degree of disturbance. The study area is one of the large ranges of oak forest in Garhwal Himalaya and compensating various types of daily needs of local people. On the basis of IVI values Quercus leucotrichophora holds first position in all the disturbance zones whereas Myrica esculenta upgraded it's rank in highly disturbed zone and showed less impacted species by disturbance. Berberis aristata and Eupatorium adenophorum in shrub layer and Anaphalis adnata and Bidens pilosa in herb layer were found as disturbance friendly species because they attained higher rank in highly disturbed zone whereas Caryopteris foetida was found disturbance-sensitive in shrub layer. The banj oak regenerated well under mid disturbance as compared to no and high degree of disturbance and a sharp downfall in the species diversity was recorded with increasing magnitude of disturbance. Density-diameter curves showed a reverse trend of lower density in higher girth classes. The results of the study should be useful for the forest management strategies.

하천구조 개선에 따른 어류 서식적합도와 물리적 교란의 상관분석 (A Correlation Analysis between Physical Disturbance and Fish Habitat Suitability before and after Channel Structure Rehabilitation)

  • 최흥식;이웅희
    • Ecology and Resilient Infrastructure
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    • 제2권1호
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    • pp.33-41
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    • 2015
  • 본 연구는 어류서식적합도 향상을 위해 유전자알고리즘을 이용한 하천의 구조개선 방안을 제시하였다. 하천구조 개선에 의한 수리특성의 변화에 따른 어류 서식적합도와 물리적 교란양상과의 상관특성을 분석하였다. 원주천의 하천 환경조사와 어류의 군집특성을 이용하여 수중 생태계를 대표할 수 있는 복원 목표어종으로 참갈겨니를 선택하였다. 참갈겨니의 서식적합지수를 사용한 서식적합도 분석은 PHABSIM 모형을 이용하였다. HEC-RAS를 이용한 수리특성 분석과 하천교란 평가방법을 이용하여 물리적 교란평가를 수행하였다. 서식적합도 향상을 위한 최적의 저수로 폭의 개선방안을 제시하였다. 하천구조의 개선에 의한 수리특성의 변화에 따른 서식적합도와 물리적 교란의 상관성을 분석하여 어류 서식적합도와 물리적 교란 평가점수의 향상이 있음을 확인하였다. 서식적합도 향상을 위한 하천의 구조 개선은 물리적 교란의 평가점수의 향상을 가져옴을 확인하였다.

서식지 교란 및 민간인통제지역 해제에 의한 두루미와 재두루미의 핵심서식지 변화 (The change of core habitats of the cranes due to release of the civilian control zone; CCZ and construction disturbance)

  • 유승화;정화영;김경순;유동수;김남신;김화정;허위행;김진한;이기섭
    • 환경영향평가
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    • 제24권4호
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    • pp.301-316
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    • 2015
  • 멸종위기 야생생물인 두루미와 재두루미는 인간에 의한 교란에 취약한 조류이다. 본 연구는 두루미류의 월동지인 철원의 민간인통제지역 중 일부 해제지역의 서식밀도 변화를 비교하여 그 중요성을 검증하고자 하였다. 또한 공사 및 비닐하우스 건설 등 교란에 의해 두루미류 핵심서식지역 범위에 대한 영향을 평가하였다. 연구결과 민간인통제지역 내에서의 공사 및 개간은 두루미류의 핵심서식지를 위축시키고, 원거리의 핵심서식지 면적을 증대시키는 영향이 있었다. 민간인통제지역의 개방은 2011년 3월에 이루어졌는데, 그 이전 이후의 3년간을 비교할 때 비닐하우스의 건립이 급격히 증가하였다. 민간인통제지역에서 해제된 지역은 비닐하우스의 건설이 집중적으로 증가하였고 개별 비닐하우스의 규모도 증가하였으며 이에따라 두루미의 취식영역이 감소하는 영향이 있었다. 하지만 민간인통제지역에서 해제된 지역임에도 불구하고 두루미의 취식밀도는 감소하지 않았고, 재두루미의 취식밀도는 오히려 증가하였는데, 이는 인근의 잠자리지역에 먹이를 공급했기 때문으로 판단되었다. 향후 민간인통제지역이 추가적으로 해제될 경우 두루미류의 서식밀도가 더욱 낮아질 것으로 예상되었다.

생태학의 새로운 분야로서 경관생태학의 발전과 역할 (Development and Roles of Landscape Ecology as An Emerging Opportunity for Ecology)

  • 홍선기;이창석
    • The Korean Journal of Ecology
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    • 제20권3호
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    • pp.217-227
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    • 1997
  • Landscape ecology is an emerging interdisciplinary ecology field to understand the holistic human and natural systems on the basis of concept and database obtained from pure ecology. Landscape ecology is an integrated ecology widely available for environmental science such as nature conservation and sustainable land-use planning. It is also a practical study as an applied ecology to restore and to manage local environment. Landscape ecological study is realized by embodiment of human disturbance system which is rigorously extending on natural system. Considering Korean status without landscape ecological studies, we briefly reviewed establishing process, study goal and methodology of landscape ecology as well as the related several concepts through current landscape ecological studies in the world. We hope that this paper will be helpful to ecologists having interest in landscape ecology.

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Responses of Shorebirds to Disturbance at Roosting Sites

  • Kim, Hwa-Chung;Yoo, Jeong-Chil
    • Journal of Ecology and Environment
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    • 제30권1호
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    • pp.69-73
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    • 2007
  • The sources and the frequency of disturbances and the responses of shorebirds to disturbances were studied at four roosting sites on Ganghwa Island and Yeongjong Island. The mean frequency of disturbance to roosting shorebirds was 2.7 per hour. Human activities contributed to the disturbance in 65% of all cases. Disturbance frequencies in saltpans were higher than those in the upper tidal zone, fishponds and salt marshes. Response patterns of shorebirds to disturbances were associated with the source of the disturbance. Disturbance caused shorebirds to change their behavior and to reduce roosting time at their roosting sites. Four patterns of responses by roosting shorebirds to disturbance were found, including: (1) leaving the roosts, (2) changing their location within the site, (3) leaving and returning, and (4) remaining in place. In the latter three response patterns, the birds tended to remain in their initial roosting sites, in contrast with the leaving pattern, which involved departing from the roosting area. Factors affecting these response patterns were time from high tide and time of day. When the time from high tide was greater, and the time of day was later, more birds stayed at the roost. The absence of sufficient alternative roosts in the study areas forced the birds to choose between tolerating the current disturbance, or moving to distant roosts.