• The Journal of Fisheries Business Administration
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• v.24 no.2
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• pp.1-16
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• 1993

Because of the radical changes in the domestic and foreign economic circumstances Koreaa fisheries is confronted with difficulties. Along the end of the UR marine products of other nations are rushing into Korea. Also migration of labor to other industries and rise of wage level in Korean fisheries deteriorate managerial conditions. But in Korea which has little natural resourses fisheries is still more important. That is \circled1 creating job opportunites \circled2 increase of income \circled3 supply of foodstuffs and animal protein \circled4 acquisition of foreign currency \circled5 enlargement of domestic market for industrial products \circled6 development of other interrelated industries \circled7 rational use of domestic resourses \circled8 diversification of population and production activites \circled9 contribution to balanced growth of national economy by the developing regional economy. These roles of fisheries in national economy mentioned above are to be excuted forward. In spite of the radical change in the economic circumstances at the end of the UR fisheries if crucial in Korea as a industry. For this our fisheries is to be made to compete with foreign fisheries. Through the cheap price and high quality our fisheries must be came to compete with foreign fisheries and meet the people's needs for marine products. For this it is necessary to maintain high productivity and competitive power. Now with the exception of a portion of the deep - sea fishing, our fisheries is generally paltry, Especially inshore fishery which is the main stock in our fisheries is very paltry and so productivity and competetive power are very low. So to develop our fisheries which has s comparative disadvantage active polices that follows below are to be promoted on a large scale. \circled1 improvement of structure \circled2 augmentation of productivity in fishing ground by making fisheries resourses \circled3 enlargement of finantial and monetary assistance \circled4 effective administration of fisheries cooperative union \circled5 activation of R&D etc These polices which need to be scientific and comprehensive are very valuable. Especially without making fishieries resources we cannot expect economy of scale, promotion of productivity and development of fisheries. And we do also endeavour to gather the results of the study and investigation about fisheries domestic and foreign and do ceaselessly put these to practical use systimatically.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.5
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• pp.1444-1458
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• 2016

The expansion of high-density aquaculture in the limited waters has caused a wide variety of problems. The problems include environmental problems nearby aquaculture sites, growth rate of aquatic organisms, quality decline of farmed fish and price fall in the market. The phenomenon of aquaculture industry happens in not only inshore but also offshore. Therefore, the fisheries authorities have been changing their policy paradigms from mass production to sustainable production based on ecosystem. Other countries, however, focusing on relieving poverty and providing protein from fish production have not recognized the degree of seriousness. When it comes to enhancing the problems, National Institute of Fisheries Science has been developing the technology of Integrated Multi-Trophic Aquaculture (IMTA) to reduce and to prevent contaminants from fish and aquaculture sites, remained feed from fish farming process. In long-terms of view, the system is one of the most sustainable fishery production methods based on ecosystem. As integration of nutrient feed system from aquatic organisms is firmly established, the earlier mentioned problems will be diminished gradually. In term of the substantiality, this study was conducted. The research on management system for IMTA also has been incorporated. This study also investigated the features and current status of IMTA and demonstrated the developed management system and direction for the future advancement.

• Journal of the Optical Society of Korea
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• v.20 no.5
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• pp.547-556
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• 2016

A fishing lamp is the instrument for attracting distributed fish to a certain place, and is the lighting system mainly used in fishery. In the inshore fishing, most fishing lamps are used for squid and hairtail jigging fishing, and the light source of the fishing lamps mainly used is metal halide with 1.5 KW in electric power consumption. We will analyze the irradiance distribution according to depth because squid is attracted towards light. To analyze irradiance distribution by such fishing lamps, data for seawater Type-II among the seawater types defined in 1976 are applied to East Sea. However, the Type-II data have limitations in analyzing precise seawater transmission characteristics, due to insufficient information on deep seawater. This paper analyzed the irradiance distribution of fishing lamps using the measurement of transmission characteristics in the seawater in East Sea up to 100 m underwater instead of Type-II data, which is not sufficient for transmission. A compensation factor was drawn between the actual measurement data and Type-II data through seawater transmission characteristics simulation.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.3
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• pp.252-261
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• 2014

Marine casualties originated from fishing vessel occupied about 70% of the whole marine casualties in Korea from 2001 to 2010, this ratio was not much changed as it was before. Therefore a pragmatic counterplan to decrease of casualties in fishing vessel is indispensable for reduction of the nationwide marine casualties. But since the casualties occurred by fishing vessel may have a different causes and counterplan according to the operating type of it, in this paper, fishing vessels classified into 12 types by operating method and inspected the causes and counterplan for that. The operating type of fishing vessel occurred the specific casualties more were jig boat in collisions and fire explosion, trap fishing boat, mixed fishing boats and inshore gill netter in collisions, stow netter in machinery damages and capsizing, offshore gill netter in machinery damages, fish carrier in collisions. It must be emphasized that the higher ranked types of vessels, especially jig boat have to take special care to the approaching vessels under way, trap fishing boat to rear look out and mixed fishing boat must keep on safety speed and be taken an education for advance the skill of operating radar as well. For all 12 types of fishing vessel, it is necessary for an operator to make strict precaution on the other vessel under way systematically and keep the regulation for preventing collisions, and for an engineer on watch to make a check the electricity and the engines periodically for reduction the fire explosion and machinery damages.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.332-344
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• 1996

The vertical profiles of the natural $^{210}Po,\;^{210}Pb\;and\;^{234}Th$, activities were measured at the upper 150 m or 200 m of water column from west-east intersection in the east-southern coastal area of the Korea Peninsula during the period from 26 to 29 April 1994 to compare the removal rates (residence time) and removal processes for $^{210}Po\;and\;^{234}Th$. At the inshore stations, the $^{210}Po$ activity was generally higher in the thermocline and its under layer than in the surface mixed layer, while represented the reversed pattern at the offshore stations. However, the $^{210}Pb$ activity decreased generally with depth. Also, the activity of $^{210}Po$ relative to its parent $^{210}Pb$ was deficient in the water column above the main thermocline, but was slightly excess or close to equilibrium in the thermocline and its under layer. The vertical profiles for the activity of $^{210}Pb$ relative to its parent $^{226}Ra$ showed the reversed pattern with the vertical variation of $^{210}Po$ excess (or deficiency). The $^{234}Th$ activity was significantly lower in the surface mixed layer and thermocline than in the deeper layer. The residence time of $^{210}Po$ ranged from 1 to 4 years at the five stations except station E8 that showed yet long residence time (approximately 10 years). The long residence time at the station E8 may resulted from the thicker surface mixed layer and subsequent the vertical mixing of $^{210}Po$ which was recycled in the lower surface mixed layer compared to at the other stations. Also, the residence time of $^{210}Po$ was shorter at the inshore stations than at the offshore stations. However, the residence time of $^{234}Th$ ranged from 52 to 74 days at all station without the significant variation, was very much shorter relative to the residence time of $^{210}Po$. The correlation between the removal rate of dissolved $^{234}Th$ and the concentration of total suspended matter (TSM) was generally positive. Therefore, it seems that the major route of the removal mechanism of $^{234}Th$ from seawater in the surface mixed layer is via adsorption onto suspended particle surfaces (most likely inorganic particles) and subsequent settling to the bottom layer. Between the removal rate of dissolved $^{210}Po$ and the concentration of chlorophyll-a was positively good correlation. Consequently, most likely the removal of $^{210}Po$ may be occurred by uptake to organisms (mainly such as planktonic debris or fecal pellets) and subsequent settling.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.4
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• pp.315-326
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• 2013

This study investigated the temporal-spatial distribution and variations in water quality parameters (temperature, salinity, pH, DO, COD, SPM, DIN, DIP, silicate, TN, TP, and chlorophyll-a) in the coastal area of Jeju, Korea, adjacent to aquaculture ponds (Aewol-ri, Haengwon-ri, Pyosun-ri, and Ilkwa-ri). Data were collected bimonthly from February 2010 to December 2011. A principal component analysis (PCA) identified three major factors controlling variations in water quality during the sampling period. Aquaculture effluent water led to large changes in nutrient levels. The highest nutrient values were observed during the investigation period. The relatively large increase in organic matter at the sampling stations coupled with sea area runoff events during the summer rainy period. Variation in chlorophyll-a concentration was mainly driven by meteorological factors such as air temperature and rainfall in the coastal areas of Aewol and Haengwon. In the coastal areas of Pyosun and Ilkwa, pollution was caused by anthropogenic factors such as discharge of aquaculture effluent water. High nutrient concentrations at the majority of the coastal stations indicate eutrophication of coastal waters, especially within a distance of 300 m and depth of 10m from drainage channels. Coastal eutrophication driven by aquaculture effluent may be harmful inshore. Events such as eutrophication may potentially influence water pollution in aquaculture ponds when seawater intake is detected because of aquaculture effluent water.

• Korean Journal of Ichthyology
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• v.21 no.3
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• pp.177-190
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• 2009

Species composition and abundance of marine organism in the Nakdong River estuary were investigated seasonally from November 2007 to November 2008. During the study period, a total of 169 species, 93 families, and 6 taxa were collected in the study area. Species included were 2 species in Bivalvia, 11 in Cephalopoda, 43 in Crustecea, 8 in Echinodermata, 6 in Gastropoda, and 99 in Pisces. The seasonal dominant species in number of individuals were Acropoma japonicum in autumn, Apogon lineatus in winter, Siphonalia spadicea fuscolineata in spring, and Crangon hakodatei in summer. Dominant species in abundance were Chelidonichthys spinosus in autumn, Liphius litulon in winter and spring, and Raja kenojei in summer. The number of species and their abundance, the species composition, and the diversity indices fluctuated with seasons. The organisms were divided into 17 groups by seasonal variation using a self-organizing map.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.389-401
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• 2016

This study attempted to present the monthly distribution of the inshore gill netters for the prevention of propeller failure caused by the damage of fishing gear by the merchant vessels in the West Sea. This study was conducted using the transmitting device of fishing location (V-Pass) data for 1 year in 2014. The grid intervals are $30minute{\times}30minute$ ($latitude{\times}longitude$) based on the section of the sea. A total of 56 sections were analyzed by constructing a grid. The results revealed that the section no. 194 with the highest density index showed no fishing gear damage accident. But the section no. 193 with a relatively lower density index showed more frequent fishing gear damage accident. It is because the section no. 193 is included in the main route of the merchant vessels. Based on this analysis, it is found that the fishing gears are not damaged in proportion to density index but risk of damage exists according to the main routes of merchant vessels. Therefore, for the safe navigation of the merchant vessels, notifying the waters of $34.5^{\circ}{\sim}35.5^{\circ}$ at latitude and $125.67^{\circ}{\sim}126^{\circ}$ at longitude, as a navigational warning area from May through September, will prevent marine accident, such as propeller failure and fishing gear damage. Accordingly, when the merchant vessels navigate in the section no. 193 and 203, the area of $34.5^{\circ}{\sim}35.5^{\circ}$ at latitude and $125.5^{\circ}{\sim}125.67^{\circ}$ at longitude is recommended for the safe navigation.

• 한국해양학회지
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• v.15 no.1
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• pp.17-33
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• 1980

The materials were obtained in the eastern Gulf of Alaska and the south- eastern Bering Sea during the cruise of the research vessel, Ohdae San, from July to October 1978. A total of 76 samples were taken by NORPAC net from a depth of 200 meters or less in coastal areas. 1. The surface water temperature in the coastal waters, varing from 9 to 10$^{\circ}C$, was lower than that in offshore waters which varied from 10 to 12.9$^{\circ}C$ in the eastern Gulf of Alaska. Thermocline was formed in the 30∼50 meter layer. Salinity of the coastal waters of Kenai Peninsula and Kodiak was 30 which was slightly lower than that of offshore. 2. The water temperature of the surface layer down to 30 meters varied from 7 to 10$^{\circ}C$ and from 1 to 9$^{\circ}C$ in the layer below 30 meters in the south-eastern Bering Sea. Meandering thermal front spread from the Alaska Peninsula to St. Matthew Island by way of St. Paul, and a thermocline was found at the 30∼50 meter layer Salinity ranged from 31.0 to 33.0 and that of northern and coastal waters was little lower than that of offshore. 3. Zooplankton biomass fluctuated from 0.1 to 23.6cc/10㎥ in the eastern Gulf of Alaska and 2.0 to 26.1cc/10㎥ in the south-eastern Bering Sea. Plankton was rich in the following areas, the inshore Kodiak waters, the northern Bering Sea, the Coastal waters and waters adjacent to Alutian islands however, poor in the central Bering Sea. In general, the south-eastern Bering Sea has a higher concentration of plankton volume than the eastern Gulf of Alaska. 4. Twenty three species representing 17 genera of copepods were identified from the samples. These were mostly composed of the cold water species, such as Pseudocalanus minutus, Acartia longiremis, Metridia lucens and Eucalanus bungii var. bungii. 5. The cold oceanic species were composed of Calanus cristatus, C.plumchrus, Metridia lucens, Eucalanus bungii var. bungii and Scolecithricella minor. The cold neritic species were Centropages abdominalis, Pseudocalanus minutus, Acartia longiremis, Eurytemora herdmanii, Pontella pulvinata, P. longipedata and Tortanus discaudatus. On the other hand, the warm oceanic species were Calanus tenuicornis and Oithona plumifera. The cosmopolitan species were Calanus finmarchicus and Oithona similis. 6. It was suggested that the cold oceanic species, Eucalanus bungii var. bungii and Metridia lucens in the south-eastern Bering Sea can be recommended as a valuable indicator species for finding the fishing grounds of demersal fish such as pollock and yellowfin sole in this area.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.3
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• pp.254-264
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• 1990

Using the meteorological data, surface weather map, and oceanographic data for 5 years(1984-1988). I investigated the characteristics of the fog occurrence and the role of the inshore in Pusan about the fog occurrence. And the meteorological data and sea surface temperature(SST), which were observed in July, 1989 in Suyoung Bay, were compared with those in Pusan. The fogs in Pusan concentrate in May, June and July. And at fog occurrence time the principal wind directions are Southwest(SW) winds, which easily supply with water vapor, and a series of Northeast(NE) wind. At the fog days pressure patterns are pattern 7 in spring time (March, April, and May) and pattern 10 and pattern 13 in summer time (June, July, and August). Also the advection fog(sea fog) is closely related with the relationship between warm and cold advection in 850~700mb and cold and warm SST rather than the increase of the instability of atmosphere in 850~500mb. The fogs in Taegu, which is the inland region, mainly occur at dawn in fall time due to the strong night radiation fog. On the other hand in Pusan the coastal region, the fogs occur from late spring time to summer time (May, June, and July). Because there is the abundant supply of the water vapor from the ocean owing to a series of South(S) wind at this time. Then the atmosphere, which has high relative humidity, reaches easily the supersaturation by the radiation cooling. In Suyoung Bay and Pusan the meteorological observation data, SST and fog days are almost similar. And I think that the mechanism of the fog occurrence nearly accords with both regions.