• Title/Summary/Keyword: reef

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Settlement Characteristics of Three Type of Artificial Reefs on Sandy Bottom in the Eastern Coast of Korea (동해안 사질지반에 시설된 인공어초 3종의 매몰 특성)

  • Kim, Dae-Kweon;Kim, Wan-Ki;Son, Yong-Soo;Yoon, Jang-Tack;Gong, Yong-Gun;Kim, Young-Dae;Lee, Ji-Hyun
    • Journal of Advanced Marine Engineering and Technology
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    • v.32 no.2
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    • pp.359-364
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    • 2008
  • Using multi beam echo sounder, side scan sonar and scuba diving equipment, ceramic type, uneven type and semicircle-ramus type reefs into sandy bottom were ascertained, the depth of submersion in 7.2-10.3m on the coast of Gangneung, East of Korea, forty uneven type artificial reefs(AR) were totally buried into the sandy bottom. Two of five semicircle-ramus type ARs had only of their top area exposed. For most of the 45 ceramic reefs, only the upper 25-150cm of ARs were visible. The burial pattern is different in west and east side of the reefs, where the east side is deeply buried compared to the west side. From these results. it is recommended that sufficient analysis of bottom structure and materials especially in the sandy sea area should be undertaken in order to determine the best type of artificial reefs to be deployed and the best location for depoloyment.

Biogeographical Distribution and Diversity of Bacterial Communities in Surface Sediments of the South China Sea

  • Li, Tao;Wang, Peng
    • Journal of Microbiology and Biotechnology
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    • v.23 no.5
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    • pp.602-613
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    • 2013
  • This paper aims at an investigation of the features of bacterial communities in surface sediments of the South China Sea (SCS). In particular, biogeographical distribution patterns and the phylogenetic diversity of bacteria found in sediments collected from a coral reef platform, a continental slope, and a deep-sea basin were determined. Bacterial diversity was measured by an observation of 16S rRNA genes, and 18 phylogenetic groups were identified in the bacterial clone library. Planctomycetes, Deltaproteobacteria, candidate division OP11, and Alphaproteobacteria made up the majority of the bacteria in the samples, with their mean bacterial clones being 16%, 15%, 12%, and 9%, respectively. By comparison, the bacterial communities found in the SCS surface sediments were significantly different from other previously observed deep-sea bacterial communities. This research also emphasizes the fact that geographical factors have an impact on the biogeographical distribution patterns of bacterial communities. For instance, canonical correspondence analyses illustrated that the percentage of sand weight and water depth are important factors affecting the bacterial community composition. Therefore, this study highlights the importance of adequately determining the relationship between geographical factors and the distribution of bacteria in the world's seas and oceans.

Marketing Practices and Value-Added Fish Product in East Indonesia

  • HIDAYAT, Sopian;PABUAYON, Isabelita M.;MUAWANAH, Umi
    • Asian Journal of Business Environment
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    • v.10 no.2
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    • pp.33-41
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    • 2020
  • Purpose: This study assesses the marketing practices and value-added fish products under the Coral Reef Rehabilitation and Management Program (COREMAP) in East Indonesia. Research design, data and methodology: This study gathered qualitative and quantitative data through i) focus group discussions (FGD) with fishers, traders and COREMAP officers, ii) surveys and iii) interviews with fishermen and traders. This study surveyed 714 households (365 in COREMAP and 349 in non-COREMAP) and 33 traders (17 in COREMAP and 16 in non-COREMAP) using structured questionnaires between January and March 2016. This study used Shepherd's Index to estimate the marketing efficiency for each stage of the marketing channel. For value-added fish products, the value is determined by the difference between processed output and the raw product used. Results: Marketing cost in the non-COREMAP area was more efficient than in COREMAP as indicated by lower operational cost and higher selling price. However, no value-added fish products were produced in the non-COREMAP area. This study noted a lower catch in COREMAP area, which implies COREMAP program successfully reduced fishing pressure. Conclusions: This study identified poor infrastructure and the limited market as the major problems in developing value-added fish products in both COREMAP and non-COREMAP area.

Home Ranges and Homing Routes of the Black Rockfish Sebastes schlegeli Measured by Acoustic Telemetry (음향 텔레메트리에 의한 조피볼락의 귀소범위 및 귀소경로 측정)

  • Kang, Kyoung-Mi;Shin, Hyeon-Ok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.41 no.3
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    • pp.221-227
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    • 2008
  • The black rockfish (Sebastes schlegeli) is an important commercial species in Korean fisheries. We used acoustic telemetry using coded ultrasonic transmitters to track the home ranges and homing routes of the black rockfish that inhabit in the Tongyeong marine ranching area. Twenty-four fish were released at five points. The distance from the capture point (C1) to the released point was 0 (R7), 0.2 (R1), 0.9 (R2), 1.3 (R3) and 1.9 (R4) km. Two of the three fish released at R1 (0.2 km) returned home in under 48hrs. Another was found 0.8km from C1. Two of the five fish released at R2 returned home, but it took over 250 days. None of the ten fish released at R3 and R4 returned home. Three of the ten fish moved 1.1-2.6 km from C1 and were found near a cage or a natural reef. Six fish were released at R7. The younger the fish, the wider was its movement range around the artificial reefs. Fish over 3 years old were likely to move less far.

Enzymatic Hydrolysis of Beef Tallow (효소에 의한 우지의 가수분해 반응)

  • 김인호;박태현
    • Microbiology and Biotechnology Letters
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    • v.19 no.4
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    • pp.377-382
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    • 1991
  • Reef tallow was hydrolyzed with lipase under the conditions of liquid state and solid state. Lipase OF 360 was used for that purpose, and the lipase had the maximum activity when the olive oil was used as a substrate at pH 6 and $37^{\circ}C$. Beef tallow was dispersed by an agitator to perform a liquid enzymatic reaction. Water content, reaction temperature, and enzyme amount were varied as parameters affecting hydrolysis percentage. Ninety three percents of tallow were hydrolyzed at the following conditions: water content 80% w/w, temperature $37^{\circ}C$, and enzyme amount 200 unitlg tallow. In order to conduct a solid phase enzymatic reaction, sonication was employed for pretreating tallow with the enzyme solution. Molten tallow was sonified with the enzyme solution, and solidified by lowering temperature. And then hydrolysis reaction proceeded at $30^{\circ}C$. Sonication intensity and time were varied to control hydrolysis percentage. Optimum values of the intensity and the time were found to exist since the hydrolysis percentage did not increase further according to the increases of the intensity and the time.

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A Study on Very High-rise Steel Artificial Reefs Based on Computer Graphics - part I (Design Aided Program Development) (컴퓨터 그래픽스 기법을 이용한 초고층 강제어초에 관한 연구(I) - 설계지원 프로그램 개발)

  • Hyun-Kyoung Shin;Ho-Gyun Park
    • Journal of the Society of Naval Architects of Korea
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    • v.36 no.1
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    • pp.99-108
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    • 1999
  • The solid modelling program was developed for the 3-D representation and analysis of VEry High-rise Steel Artificial Reefs(VEHSAR) using Visual C++ on the Microsoft's Windows 95(or Windows NT) based on MFC(Microsoft Foundation Class). Importing oriented-object program and CAD/CAM technique, this integrated design system which aims at low cost and high efficiency makes it possible to predict problems and to establish counterplans through visualizing the construction of Very High-rise Steel Artificial Reefs in advance. Also it is useful in enhancing productivity. Introduction of OpenGL makes it display high quality 3D graphics more faster.

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Changes in the Orientation and Frequency Dependence of Target Strength due to Morphological Differences in the Fish Swim Bladder (어류 부레의 형태학적 차이에 따른 음향산란강도의 자세 및 주파수 의존성의 변화)

  • Lee, Dae-Jae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.48 no.2
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    • pp.233-243
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    • 2015
  • Controlled broadband acoustic scattering laboratory experiments were conducted using a linear chirp signal (95-220 kHz), and x-ray images of live and model fish with an artificial swim bladder were analyzed to investigate the changes in orientation and frequency dependence of target strength (TS) due to morphological differences in fish swim bladders. The broadband echoes from live and model fish were measured over an orientation angle range of ${\pm}45^{\circ}$ in the dorsal plane and in approximately $1^{\circ}$ increments. The location of nulls in the simulated echo response of the SINC [sinc function] model was overlaid on the TS map, showing the orientation and frequency dependence of fish TS, and they matched very well. It was possible to infer the equivalent fish scattering size (or swim bladder) using the null spacing in the experimentally obtained broadband TS map. Good agreement was observed for inferring the equivalent scattering size between the SINC model and the broadband echoes measured for the three fish species (black scraper Thamnaconus modestus; goldeye rockfish Sebastes thompsoni; and whitesaddled reef fish Chromis notatus). Some results of this inference are discussed.

A Review-Status of Development and Research of Artificial Reefs in the East Asian Countries- (동아시아의 인공어초 개발과 연구 현황)

  • LEE, Moon-Ock;KIM, Jong-Kyu;KIM, Byeong-Kuk
    • Journal of Fisheries and Marine Sciences Education
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    • v.28 no.3
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    • pp.630-644
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    • 2016
  • We conducted a comprehensive review on artificial reefs (ARs) including seaweed reefs for marine afforestation in relation to their development and research from 1972 to 2016, and then systematically analyzed their current a state-of-the-art and practice. From the review, the followings conclusions are made. First, the objectives of AR projects in the Southeast Asia can be classified into three, i.e. protection and increase of fishery resources, local community's profits, and ecological tourism. Second, fish gathering effects by ARs can be determined in terms of wake region or wake length that tends to increase with the K-C (Keulegan-Carpenter) number. Third, ARs are desirable to deploy across a direction of the main flow but it is essential to keep the deployment interval two to four times the length of a single reef. Fourth, stability of ARs depends on how to evaluate drag coefficient, and Morison formula turns out to be practical. Fifth, local scours of ARs are likely to occur due to a downward flow around the center of the front surface. Finally, it is natural for ARs to positively contribute to the marine ecosystem but it is imperative to develop an evaluation method for the effects of ARs on the marine ecosystem.

Habitat change monitoring using high-spatial satellite image around the topical coastal area (고해상도 위성영상을 이용한 열대해역 생태분포 변화 모니터링)

  • Min, Jee-Eun;Ryu, Joo-Hyung;Kim, Key-Lim;Park, Heung-Sik
    • Proceedings of the KSRS Conference
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    • 2009.03a
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    • pp.26-30
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    • 2009
  • 본 연구는 고해상도 위성영상을 이용하여 열대해역에서의 생태환경 분포도를 작성함으로써 생태 환경의 변화를 효과적으로 모니터링 할 수 있도록 하는 데에 목적이 있다. 지구온난화 현상에 따라 산호 면적이 감소하고 있다. 이처럼 산호는 환경 변화가 민감하게 반응을 하기 때문에 열대해역에서 산호를 모니터링 하는 것은 주변 생태환경 변화 전체에 대한 관리 역할을 하기 때문에 중요하다. 본 연구에서는 이러한 열대해역의 환경을 효과적으로 모니터링 하기위하여 고해상도 위성영상인 IKONOS와 Kompsat-2 영상을 이용하여 생태환경 분포도를 작성하여보았다. 연구지역은 한남태평양연구센터가 위치한 마이크로네시아 연방국의 Weno 섬 북동쪽 연안이고, 이 지역에서 2007년과 2008년 2번의 현장관측을 실시하여 총 121개 정점에서 광관측 및 환경 자료를 얻었다. 기존의 감독분류와 무감독분류 방법, 그리고 객체지향 영상분류 방법 등을 이용하여 분포도를 작성하였고, 현장관측 자료를 이용하여 검증하였다. 고해상도 영상이기 때문에 기존 방법에서 나타나는 오분류 현상이 객차지향 영상분류 방법을 사용할 경우 적어지는 결과를 얻을 수 있었다.

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Food Components of Striped Jewfish Stereolepis doederleini (돗돔(Stereolepis doederleini)의 식품성분)

  • Moon, Soo-Kyung;Kim, In-Soo;Ko, Yeong-Sin;Park, Jeong-Hee;Kim, Geum-Jo;Jeong, Bo-Young
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.5
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    • pp.550-553
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    • 2011
  • The proximate, fatty acid and total amino acid compositions of striped jewfish Stereolepis doederleini muscle were studied. The proximate composition was: 76.4% moisture, 19.4% protein, 2.92% lipid, and 1.19% ash. The predominant total lipid fatty acids were 16:0 (18.7%), 18:1n-9 (16.5%), 22:6n-3 (16.0%), 16:1n-7 (8.53%), 20:5n-3 (7.97%) and 18:0 (5.34%). Glutamic acid (17.4%), lysine (10.6%), aspartic acid (10.4%) and leucine (8.27%) were the predominant amino acids in striped jewfish muscle. These food components of striped jewfish were similar to those of costal and reef dwelling fishes such as black rockfish, black sea bream and rock trout, which are common sliced raw fish in Korea. Therefore, these results suggest that striped jewfish may represent a new aquaculture fish species.