• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.625-637
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• 2022

The southern coast of the East Sea is an important area affected by large warm currents as it connects the coastal waters of Jeju Island, the South Sea, and Dokdo. From 2017 to 2021, the average catch per unit effort (CPUE; kg/day/ship) of set net fishery at six ports in the Gyeongbuk region off the southern coast of the East Sea was the highest in Gampo, Gyeongju, and the lowest in Hupo, Uljin. Although the seasonal variation in the CPUE differed by region and year, it was generally high in autumn. In the set net fishery in Pohang from 2019 to 2021, we identified 72 species, which decreased to 56 species in 2019, 46 in 2020, and 41 in 2021. The species diversity index slightly increased over the three-year periods. We found positive correlations between the total catch (kg) of subtropical species in autumn and the water temperature at 50 m. Among the most abundant species, we found substantially positive correlations between the CPUE of Scomber japonicus, Scomberomous spp. and Carangids. We also noted positive correlations between the CPUE of Todarodes pacificus, Seriola spp. and Carangids.

• Fisheries and Aquatic Sciences
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• v.26 no.6
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• pp.380-392
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• 2023

Groupers (Family Epinephelidae) are commonly caught in data-poor small-scale multi-species fisheries for sale on both export and domestic markets. This study presents data on the species composition and size/life-stage structure of Epinephelus spp. groupers caught by small-scale fishers and sold locally in the Indonesian province of South Sulawesi. Data were collected from fishing ports and local markets at 12 sites representing the three seaways around South Sulawesi (Makassar Strait, Flores Sea, Gulf of Bone). Each specimen (n = 3,398) was photographed alongside an object of known length, and total length (TL) was obtained using the Rapid Scaling on Object (RASIO). Of the 23 species identified, four (Epinephelus areolatus, Epinephelus ongus, Epinephelus quoyanus, and Epinephelus fasciatus) collectively comprised 69% of the catch, while the 13 least abundant species contributed less than 5%. The catch was dominated (67%) by the subadult life-stage, with just under 20% in the adult class. Juveniles dominated the catch of Epinephelus fuscoguttatus, a valuable export commodity. Observations of early maturity as well as the sizeable gap between length at first capture (Lc) and length at first maturity (Lm) indicate recruitment overfishing of most species, with the notable exception of Epinephelus rivulatus. The proportion of adult fish was low (≈5%-30%) for the twelve most abundant species (E. areolatus, E. ongus, Epinephelus quoyanus, E. fasciatus, Epinephelus coioides, Epinephelus faveatus, Epinephelus sexfasciatus, Epinephelus maculatus, Epinephelus bleekeri, Epinephelus corallicola, E. fuscoguttatus, Epinephelus polyphekadion). For two moderately abundant species (E. faveatus and E. malabaricus), TL < Lm for all specimens. The limited data available indicate spawning ratio is lower than reported from deep-water fisheries of E. areolatus and E. coioides. The results call for targeted research to fill knowledge gaps regarding the biology and ecology of groupers exploited mainly for domestic markets; highlight the need for species-level data to inform management policies such as minimum legal size regulations; and can contribute towards species-level status assessments.

• Journal of the Korean Geosynthetics Society
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• v.13 no.1
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• pp.71-83
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• 2014

Busan is located at the mouth of Nakdong River and if an earthquake occurs, it is very likely that the damage by the earthquake will be worse as liquefaction can happen in the sand layer, builtup soil, and landfill ground due to amplification in the lower sedimentary layer that is well developed in the river mouth. Therefore, this study first examined the possibility of liquefaction in the replaced sand layer under breakwater using 14 earthquakes in 5.6-7.9 scale and artificial earthquakes including the seismic wave suggested in the standard specifications for seismic design of ports and fishing port facilities to evaluate the stability of breakwater which is the primary protective structure for port facilities against earthquakes. Second, analysis on characteristics of the seismic energy and acceleration response spectrum by size of earthquake was performed to suggest the most appropriate size of seismic wave for the condition in Korea. Third, finite element analysis was performed using the suggested seismic wave to study the characteristics of earthquake by finding the dynamic lateral displacement of breakwater and verifying the stability of structure and the displacement and forces occurring at geotextile. Results of the study showed that the possibility of liquefaction in the landfill and replaced sand layer, the dynamic lateral displacement of breakwater, and changes of geotextile are greatly affected by the subsurface ground (replaced sand layer).

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.3
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• pp.211-217
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• 2016

In case of the Sea Areas Utilization Consultation about fishery harbor facilities there has been problems excepting a mooring facility and having the same scope of business subject with harbor, while those scale are different. In this study, we analyzed the 17 cases of the statements for Sea Areas Utilization Consultation according to the development projects of fishery harbors for 2013-2014 and suggested the improvement way to go. First, it is needed to reassess the scope of business subject about fishery harbor because the environmental effects about the development projects for the fishery harbor are not considered separately by facilities, development project for the fishery harbor. Therefore, the reassessment about them are needed surely. Second, the adjustment of the range about fishery harbor facilities on the Sea Area Utilization Consultation is needed because in case of most small fishery ports, the sizes of those facilities are less than the boundary area ($50,000m^2$). Last, consultation subjects shall be more clear in order to protect confusions-related with applying for the Consultation on Utilization of Sea Areas. A new rule for clarifying consultation on business subjects is needed in order to reduce the unclarity and the confusions from being occurred by difference between 'occupancy or use permit of public waters' and 'exclusion of application' and business subjects according to the Public Waters Management and Reclamation Act and the Marine Environment Management Act, respectively.

• Korean Journal of Environmental Biology
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• v.34 no.4
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• pp.292-303
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• 2016

This study described the spatial distributions of marine environmental factors such as water temperature, salinity, chlorophyll a concentration and turbidity, and characteristics of phytoplankton community such as species composition, standing crops and dominant species at 19 fishing ports around Jeju Island during the early summer of 2016. I analyzed bio-oceanographical characteristics using principal component analysis (PCA) of the environmental factors and biological parameters. Water temperature, salinity, chlorophyll a and turbidity ranged from 17.6 to $20.7^{\circ}C$, from 26.19 to 32.33 psu, from 0.76 to $7.13{\mu}g\;L^{-1}$, and from 0.51 to 14.49 FTU, respectively. A total of 51 species of phytoplankton belonging to 35 genera were identified. In particular, diatoms and dinoflagellates accounted for more than 56.8% and 27.4% of all the species, respectively. Moreover, the number of phytoplankton species was controlled by salinity. Phytoplankton cell density ranged from $2.9cells\;mL^{-1}$ to $185.9cells\;mL^{-1}$. The dominant species were Navicula spp. Stephanopyxis turris, Eutreptiella gymnastica and Mesodinium rubrum. Environmental factors and the phytoplankton community varied greatly between sampling sites. According to PCA, the biological oceanographic characteristics of the around Jeju Island were characterized by meteorological factors such as air temperature, precipitation and discharge of ground water during early summer.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.28 no.6
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• pp.408-415
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• 2016

Small fishing ports and coastal structures installed in a relatively low sea water depth disturb the wave induced current and cause the collapse of equilibrium state of sediment transport. These structures creates diffracted waves and matter the concentration of waves to cause the beach erosion. In order to mitigate these eroding problems on the beach, many counter measurements were proposed such as detached breakwater, groin or headland; however, these methods interrupt the aesthetic view of sandy beach due to the exposed structures above the sea level and have difficulty of applying to those beaches with the good scenery. Furthermore, some of these methods create secondary environmental problems after the installations. To eliminate these problems, one of the countermeasures, artificial reefs have been selected and used worldwide to minimize the disturbance of the scenery and secondary effects on the environment. Meanwhile, it is important to set the design elements for installing the artificial reefs such as that of length, opening width, clearing distances from the shoreline and more. Nevertheless, there are no construction manuals or standards for designing the artificial reefs with these important design elements yet. In this study, different conditions of artificial reefs were used with various cases throughout hydraulic model test to precisely analyze the changes of waves and currents to propose the standards of design elements to install the artificial reefs.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.2
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• pp.78-82
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• 2005

Fishermen have higher risk of occupational injuries and disease due to frequent machine usage and direct contact to live biological materials. Moreover, growing elderly workers makes the susceptibility to occupational injuries and disease higher. This study was performed to investigate the occupational safety and health status among fishermen. The interview was carried out at Jumunjin and Geojin ports which were representative port at North East side of Korea. The structured questionnaire were used to interview the fishermen from AM 6:00 to PM 11:00 and total respondent were 97 workers. The results were followed; 7 fishermen of all respondents experienced occupational injuries during their work, 5 fishermen were needed to admission longer than 4 days. The injury types were contusion(4 persons), fracture(1 persons) and amputation(2 persons). The cause of injury might be the lack of caution and the unstability of working condition. These results suggested the ergonomical evaluation of working condition and proper management. But there was limited concern and studies on the policy on occupational safety and health on fishermen. So, further study was required to establish the sound policy of fishermen's occupational safety and health.

• Journal of Digital Convergence
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• v.14 no.12
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• pp.35-42
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• 2016

This study investigated development method of governance of local residence, central and local government based on fishing ports as a new paradigm for restoration of sustainable space environment on Hyeonpo Harbor in Ulleung Island. According to the result of conducting a questionnaire survey on residents of Ulleung Island in order to carry out the research purposes, vulnerable living environment as poor accessibility and lack of hospital, community health center, and shopping district were pointed out as the biggest problem of residential environment in Ulleung Island of today. Secondly, there was a high recognition that development project on Ulleung Island of the government and local government is not actually contributing to the revitalization of regional economy and improvement in quality of life of Ulleung Island residents, and thirdly, lack of understanding on the importance or usage of various resources in Ulleung Island and insufficient support of the central government and local autonomous entity were pointed out as the bottleneck factors in implementation of the Ulleung Island development project. Fourthly, they perceived the current management level of Hyeonpo Harbor to be unsatisfactory. The results of this study demonstrated the importance of durability of development entities, vision of development of Hyeonpo Harbor, effort for the change of ownership mind, phased implementation considering reality of the area, and development that can provide small-scale profitable contents than a large theme.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.2
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• pp.77-82
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• 2017

Recently, the possibility of abnormal waves of which height is greater than design wave height have been increased due to the climate change, and therefore it has been urgent to secure the stability for harbor structures. As a countermeasure for improving the stability of conventional caisson breakwaters, a method has been proposed in which adjacent caissons are interlocked with each other to consecutively resist the abnormal wave forces. In order to reflect this research trend, the reduction effect of the maximum wave force resulted from introducing a long caisson has been presented in the revision to the design criteria for ports and fishing harbors and commentary. However, no method has been proposed to evaluate the stability of interlocking caisson breakwater. In this study, we consider the effect of the phase difference of the oblique incidence of the wave based on the linear wave theory and apply the Goda pressure formula for considering design wave pressure distribution in the vertical direction. Sliding stability assessment formula of an interlocking caisson breakwater is proposed for regular, irregular, and multi-directional irregular wave conditions.

• Journal of the Korean Geographical Society
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• v.41 no.4 s.115
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• pp.491-506
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• 2006

In terms of the importance of ocean as a present and future resource and the Korean peninsular location, it is strongly urged to develop renewed recognition and educational programs on ocean, so as to respond properly to the newly emerging political changes surrounding the country. By setting up the purpose of marine education as engendering greater interests in and knowledge of ocean, this research suggests that the frame of marine education can be founded appropriately on four educational sub-categories: humanity education, territory education, economy education, and resources and environment education. At an operational scale, this paper particularly analyzed ocean- related contents in the 7th national curriculum in order to find substantial ways for strengthening marine education. The study simultaneously compared the result of content analysis with the curriculum of marine education in other countries, and founded that explicit ocean-related contents in the 7th curriculum were significantly limited. Yet, the study alternatively points out that it is possible to use a variety of teaching materials and apply them for writing textbooks or developing teaching-teaming curriculum. I provide some of the ways for strengthening marine education by using marine-related themes in the curriculum of geography education. Marine is not simply one of the key elements in the discipline of geography. But, more importantly, I suggest that geography is particularly useful in developing various and familiar themes such as swimming beach, fishing villages, ports, marine-bound industrial district and port cities into teaching materials.