• 제목/요약/키워드: reef

검색결과 242건 처리시간 0.031초

First Records of Two Pontoniid Shrimps (Crustacea: Decapoda: Caridea: Palaemonidae) from Korea

  • Lee, Kyu-Hyun;Ko, Hyun-Sook
    • Animal Systematics, Evolution and Diversity
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    • 제27권3호
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    • pp.239-245
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    • 2011
  • We describe and illustrate two pontoniine shrimps, Cuapetes grandis and Periclimenes ornatus, for the first time in Korea. C. grandis was collected in an artifical reef of Dadae, Geojedo Island by SCUBA diving in 15-20 m depth. This species was found in an oyster within an artificial reef and appeared to be free-living. P. ornatus was collected from Seongsanpo, Jejudo Island by SCUBA diving in 10 m depth. This species had a symbiotic relationship with sea anemone. This record extends their previously known range from southern Japan to the Korean peninsula and the number of known pontoniine species in Korea to four.

매립석탄회를 활용한 인공어초 제조기술 개발 (Development of manufacturing technology of Artificial Reef Mixed with Reclamation Coal Ash)

  • 한상묵;조명석;송영철
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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    • pp.125-128
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    • 2005
  • Coal ash, which is generated as a byproduct at a coal thermal power plant, can be classified into fly ash and bottom ash. Most of fly ash is recycled as an admixture for concrete, while bottom ash is not recycled but dumped into an ash landfill disposal site. So, if a technology for recycling bottom ash efficiently, which is increasingly generated year by year, is not developed, environmental problems will take place as a matter course and further an enormous economical cost will be required for construction of additional ash landfill disposal sites. In this study an optimum mix proportion design and a quality control method for utilizing the reclamation coal ash as an aggregate for secondary concrete products such as an artificial reef was successfully developed.

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Detection of Small Shallow-water Coral Reefs on Landsat Imagery

  • Trisirisatayawong, Itthi;Samanloh, Watcharee
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.479-481
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    • 2003
  • Large number of coral reefs in Thailand waters make the use of satellite imagery probably the only practical method for their monitoring. This paper reports the result of detecting small shallow-water coral reef by using maximum likelihood classification technique. Combination of blue/green and near-infrared band ratio are used as spectral signatures derived from a Landsat 7 imagery covering western portion of the Gulf of Thailand. Result assessment reveals accuracy significantly over 60 percent. The result is encouraging and would be a basis for further study to realize the full potential and limitation of this technique.

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AHP 기법을 이용한 바다목장화사업 성공요인에 대한 비교평가연구 (The Comparative Evaluations of the Factor Weights for a Successful Sea-ranching Project based on AHP)

  • 박철형;표희동
    • 수산경영론집
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    • 제38권3호
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    • pp.67-88
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    • 2007
  • This study is to estimate the factor weights for a successful sea-ranching project using the Analytical Hierarchy Process. Furthermore, it investigates the policy implications revealed by the differences in group opinions throughout fishermen, government officials, researchers and the scholars when the weights are assessed. The hierarchy is constructed for the 3 levels of factors which must be evaluated for a successful sea-ranching project. The top level of factors is divided by the ecological factors and the socioeconomic factors. As the middle level of factors, there are 3 factors such as the choice of fish, the habitat environment and the production technology under the ecological factors and another 3 factors such as the stability of fishery society, economic factors, and the law & system under the socio-economic factors. And then, at the bottom level of the hierarchy, the economic factors have two different sub-factors such as the fishing revenue and cost. The law & system has also 3 sub-factors such as the accessibility to sea-ranching area, fishing method, and surveillance. The fishermen and government officials show us quite opposite tendencies in assessments of the weights while both the researchers and scholars reveal almost the same opinions positioned at somewhere between first two groups. The study also reports the evaluations of efficiency measures for resource recovery methods among the sea-ranching project, artificial reef, release of fish seeds, and marine protection area. Both the sea-ranching project and marine protection area have the same efficiency in terms of resource recovery while the artificial reef and release of fish seeds are revealed as somewhat less efficient methods comparing to the former two methods.

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제주도에서 흑로 Egretta sacra의 식이물과 취식 영역 (The Food Resources and Foraging Sites of Pacific Reef Herons(Egretta sacra) in Jeju Island, Korea)

  • 김완병;오홍식
    • 한국환경생태학회지
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    • 제23권6호
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    • pp.564-568
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    • 2009
  • 본 연구는 2005년 2월부터 8월까지 제주특별자치도 애월읍 신엄리에서 흑로의 식이물과 취식 영역을 조사하였다. 수거한 식이물은 모두 5종 21개체였으며, 이중 검정망둑(Tridentoger obscurus)이 38.1%(n=8)로 가장 많았고, 다음이 가막베도라치(Ennedpterygius etheostomus)가 19.0%(n=4), 멸치(Engraulis japonica)가 14.3%(n=3) 순이었다. 식이물의 크기는 평균 $58.29{\pm}5.17mm$(n=19)였으며, 검정망둑 $67.49{\pm}4.91mm$(n=8), 가막베도라치 $43.98{\pm}3.50mm$(n=4), 멸치 $22.77{\pm}1.17mm$(n=3), 반쯤 소화된 상태의 넙치(Paralichthys olivaceus)와 볼락(Sebastes inermis)도 확인되었다. 먹이활동이 이루어지는 취식 영역은 번식지를 기점으로 동쪽으로는 7.4km 지점의 외도천 하류까지, 서쪽으로는 6.6km 지점의 애월읍 금성천까지로 나타났다.

Spatial and temporal dynamics of the abundance of crustose calcareous algae on the southernmost coral reefs of the western Atlantic (Abrolhos Bank, Brazil)

  • Amado-Filho, Gilberto M.;Bahia, Ricardo G.;Mariath, Rodrigo;Jesionek, Michel B.;Moura, Rodrigo Leao;Bastos, Alex C.;Pereira-Filho, Guilherme Henrique;Francini-Filho, Ronaldo Bastos
    • ALGAE
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    • 제33권1호
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    • pp.85-99
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    • 2018
  • Crustose calcareous algae (CCA) constitute one of the main reef builders on the Abrolhos Bank, Brazil. Once CCA taxonomy is locally understood, differences in growth-forms may be useful for the delimitation of taxa using characteristics such as the presence or absence of surface protuberances. Here, growth-forms were used to identify and quantify the most common CCA taxa on the shallow reefs (3-10 m) of the Abrolhos Bank to determine possible changes in the CCA community over a period of 10 years, and the ecological significance of CCA to local reefs was interpreted. The CCA assemblages were surveyed from 2006-2015 by using fixed photoquadrats at four sites in the inner (10-20 km from the mainland) and mid-shelf reefs (40-75 km from the mainland). The five most common CCA taxa were Pneophyllum conicum, the Lithophyllum kaiserii / Lithophyllum sp. complex, Melyvonnea erubescens, the Hydrolithon boergesenii / Porolithon onkodes complex and Peyssonelia sp. The overall mean CCA cover on the reefs was 20%. A comparison with a previous monitoring study in the same region indicated that the CCA cover nearly doubled from 2003-2008 to 2006-2015. This study reveals that the coral-killing species P. conicum dominated CCA flora on the shallow Abrolhos reefs in the last decade, and the local specific abundance of CCA slightly fluctuated over time and was species- and site-specific. The information obtained in this study contributes to the understanding of the ecology of the key calcifying components of the Abrolhos reefs and provides a useful baseline for exploring the responses of CCA to future environmental changes.

연산호 육성용 어초 개발을 위한 송이 다공성 콘크리트의 적용성에 관한 실험적 연구 (An Experimental Study on the Application of Porous Scoria Concrete to Artificial Reefs for Soft Coral)

  • 홍종현;김문훈;김석철;박성배;류성필
    • 한국해양공학회지
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    • 제19권4호
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    • pp.28-34
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    • 2005
  • In the study application of volcanic scoria concrete to artificial reefs is investigated. Volcanic scoria is a natural volcanic product that shows light weight, mil/i-porous, and far-infrared irradiation characteristics. The properties of volcanic scoria concrete using Jeju scoria aggregate are evaluated by conducting a comprehensive series of tests on strength and void ratio. It is concluded that the volcanic scoria concrete has the sufficient strength of 4MPa-13MPa and adequate void ratio of $12\%-35\%$ to be accepted as artificial reef concrete. The field experiments are performed through observation by scuba diver's at the Seogwipo coast. Porous specimen and plane concrete specimen are prepared for comparison purposes. Seasonal changes of soft coral on the two series of test specimens were have been observed from Apr. 9, 2004 to Mar. 18, 2005. The soft coral is well grown on the porous specimen however there are no significant changes on the conventional plain concrete specimen. Thus it is concluded that the volcanic scoria concrete is highly suitable as artificial reef concrete.

Coral Reefs in Indonesia: A Review on Anthropogenic and Natural Disturbances

  • Meinita, Maria Dyah Nur
    • 한국해양바이오학회지
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    • 제2권1호
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    • pp.1-10
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    • 2007
  • Coral reefs are among the most dynamic and various ecosystems on tropical ecosystem. They provide a large number of important ecosystem services. Despite their importance, they appear to be one of the most susceptible marine ecosystems. Dramatic decreasing of coral reefs has been reported from every part of the world. Indonesia contains 18% of coral reefs of world's total. Unfortunately the status of coral reefs in Indonesia is already in critical and poor condition. Coral reefs communities in Indonesia are subjected to a variety of environmental disturbance. Threats to Indonesia's coral reefs resources can be divided into two main types: anthropogenic and natural disturbances. The major anthropogenic disturbances on coral reefs in Indonesia are destructive fishing, pollution, coastal development, mining and harvesting live fish and coral, tourism. The natural disturbances such as cyclones, volcanic eruptions, earthquakes, tsunami and predator also contribute to coral reefs destruction in Indonesia. In my paper I tried to compare between natural and anthropogenic disturbances on coral reefs in Indonesia and raised these questions: (i) how the natural disturbances differ from anthropogenic area (ii) which type of disturbances has caused the greatest impact on coral reef ecosystem. My finding is that both of anthropogenic and natural disturbances give major impact on coral reefs in Indonesia. The important issue here is coral reef resilience could be disturbed by synergistic effects between various anthropogenic and natural disturbances. This phenomenon has significant conservation and management implication. The appropriate management should be conducted to protect coral reefs ecosystem in Indonesia. Mangrove management will succeed only when local people are involved and get sustainable benefits from mangrove ecosystem. Community based management and Integrated Coastal Zone Management (ICZM) are type of management that can be applied on coral reef ecosystems in Indonesia.

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수리실험을 통한 요철형 인공어초 안정성 검토 (Hydraulic model test for corrugated artificial reef stability)

  • 백승화;신범식;김규한
    • 한국산학기술학회논문지
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    • 제15권8호
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    • pp.5327-5332
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    • 2014
  • 우리나라 연안생태계는 백화현상(갯녹음)에 의한 해조류의 감소와 어패류 등 어업자원의 감소로 인해 연안역의 황폐화에 직면해 있다. 새로운 유형의 인공어초에 대한 안정성을 평가하기 위해 본 연구에서는 2차원 단면수조를 이용하여 새롭게 개발된 인공어초의 설치수심에 따른 재현파고, 주기, 흐름 등 외력을 변화시켜 요철형 어초의 안정 조건이 되는 한계치를 구하고, 설계외력(파랑, 흐름 등)의 안정성에 대한 검토를 수행하였다. 본 연구 결과는 새로운 인공어초의 설계 및 실해역에 시공하기 위해 구조물의 안정성을 사전에 검토할 수 있는 있는 기초자료를 제공할 수 있을 것으로 판단된다.