• Journal of Wetlands Research
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• v.3 no.2
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• pp.107-118
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• 2001

The aim of this paper is to grasp eutrophication aspects in Namhae coastal seas, statistically analyzing existing data for their surface seawater and bottom mud. A pollution level(ignition loess) of bottom mud, on the whole, trended to increase as moving the coastal sea around Mokpo-Wando toward the east(Gyeongnam Namhae coastal seas). Especially, the pollution level(ignition loss=10.5%) of bottom mud for the coastal sea around Tongyeong-Keoje-Gosung was similar to that(10.3%) for the coastal sea around Masan-Jinhae, whose coastal marine pollution was the severest in Namhae coastal seas. It indicates that large amounts of pollutant from aqualculture facilities have been, thus far, accumulated on the coastal sea around Tongyeong-Keoje-Gosung, considering there was no significant inflow of sewage and industrial wastewater into this coastal sea. A COD, T-N, and T-P level of surface seawater, on the whole trended to increase as moving the coastal sea around Mokpo-Wando toward the east(Gyeongnam Namhae coastal seas). A COD level appeared to be the second grade of coastal water quality over the entire year throughout all Namhae coastal seas A T-N level exceeded the third grade of coastal water quality throughout all Namhae coastal seas except the coastal sea around Mokpo-Wando. Especially, a T-N level exceeded as many as three and six times over the third grade of coastal water quality in the coastal sea around Tongyeong-Keoje-Gosung and Masan-Jinhae, respectively. A T-P level appeared to be the second grade of coastal water quality in the coastal sea around Mokpo-Wando and the third grade of coastal water quality in the coastal sea around Yosu-Narnhae and Tongyeong-Keoje-Gosung, while it exceeded as many as two times over the third grade of coastal water quality. A degree of eutrophication of the surface seawater was 1.5 in the coastal sea around Mokpo-Wando and 11.9 In the coastal sea around Tongyeong-Keoje-Gosung, gradually increasing as moving toward the east(Gyeongnam Narnhae coastal seas). It sharply increased to 146.1 in the coastal sea around Masan-Jinhae. Because the degree of eutrophication throughout all Namhae coastal seas exceeded 1, a red tide organism could pose a possibility of proliferation at any place of Namhae coastal seas if other requirements were satisfied. It indicates that a red tide may move to another place once a red tide breaks out at a place of Namhae coastal seas.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.3
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• pp.217-232
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• 2019

It was turned out by shrimp beam trawl monthly survey from March, 2015 to February, 2016 that different species composition and abundance of the fish assemblages in Sacheon Bay and coastal waters off Namhae, Korea were compared. As a result of monthly measured sea temperature and salinity of Sacheon Bay and coastal waters off Namhae, sea temperature of both areas was changed seasonally; however, differences in sea temperature occurred during certain periods depending on the region. Salinity was generally low in Sacheon Bay affected by fresh water, and both areas was low in summer and high in winter. A total of 73 species representing 37 families were collected in Sacheon Bay. The dominant fish species in terms of numbers and biomass were Liparis tanakae, $23,077inds./km^2$, $332.1kg/km^2$. A total of 91 fish species representing 49 families were collected in coastal waters off Namhae. The dominant fish species in terms of numbers were Leiognathus nuchalis, $139,683inds./km^2$ and biomass were Chelidonichthys spinosus, $1,078.6kg/km^2$. Analysis of dendrogram of the clustering showed that Sacheon Bay and coastal waters off Namhae were distinctive featured (global R = 0.691, p = 0.017). And except of summer season (July-October), there was a distinctive feature seasonally (global R = 0.844, p = 0.001). The fish species that appeared in common in both areas, where fish species caught in Sacheon Bay, an important inner bay,were smaller than those caught in coastal waters off Namhae appeared. It presented that Sacheon Bay plays a more important role in spawning and nursery ground for fisheries resource than coastal waters off Namhae, Korea.

• Korean Journal of Ichthyology
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• v.22 no.4
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• pp.256-266
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• 2010

The distribution characteristics of the eggs and larvae of anchovy Engraulis japonica, and environmental factors in the southern coastal waters of Korea were investigated from May to August 2009. Eggs and larvae were mainly distributed in the waters off Naro Island, Namhae Island and Saryang Island. High densities of eggs and larvae in temperatures of $19.0{\sim}24.0^{\circ}C$, salinites of 33.0~34.4 psu, DO of 6.05~8.13 mg/L and chlorophyll-a $1.2{\sim}2.3{\mu}g/L$ were observed. Water temperature in the coastal region was higher than that in the open sea, while salinity was lower. Evidence of sea water intrusion toward Sori Island and Maemul Island, and an inner-water intrusion from Yeoja Bay, Gamak Bay and Gwangyang Bay were observed. High densities of eggs in early developmental stage occurred in waters off Naro Island, Dolsan Island and Namhae Island, but high densities of eggs in a later developmental stage occurred in waters off Yokji Island and Maemul Island. During the survey period, the proportion of later developmental-stage eggs was higher in the eastern part of the study area.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.4
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• pp.938-945
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• 2004

On the relationship between the red tide occurrence and the oceanographic factors in the middle coastal area in the South Sea of Korea, the favorable oceanographic conditions for the red tide formation are considered as follows； the calm weather increases sea water temperature in summer and early-fall which the red tide occurs frequently, and the heavy precipitation brings some riverine water to ween: low salinity, high suspended solid, low phosphorus and high nitrogen, respectively. We decided the potential areas in the coastal zones vulnerable to the red tide occurrence based on the limited factors controlling the growth of phytoplankton. By using GIS through the overlap for three subject figures (phosphorus, nitrogen and suspended solids), it was founded that the potential areas are the Yeosu∼Dolsan coast, the Gamak bay, the Namhae coast, the Narodo coast, the Goheung and Deukryang bay. This result has very well coincided to the results of the satellite and in-situ data.

• ALGAE
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• v.18 no.1
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• pp.49-58
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• 2003

The short-term dynamics of the summer phytoplankton community structure were investigated in coastal waters around Namhae Island, the Southern Sea of Korea. The study was based on a comprehensive survey constituting 39 collections from 13 stations on July 18-22, August 1-2, 14-16 and 27-30, respectively. The community structure was analysed using cluster analysis and important environmental correlates of the assemblage structure were identified with canonical correspondence analysis (CCA). Water temperature, salinity, NO₂, NO₃, NH₄, PO₄, chlorophyll a and transparency were measured as physico-chemical environmental factors which may be associated with the phytoplankton community structure. Variations of salinity and concentrations of NO₃ and chlorophyll a were not significant. In addition to warmer water temperature, concentrations of NO₂, NO₄and PO₄ decreased at the beginning of August. And transparency was deeper and water column became very unstable after the middle of August. A wide taxonomic diversity was encountered during the survey, including a total of 121 taxa which was composed of 72 diatoms, 48 dinoflagellates and 1 euglenoid species. Cluster analysis showed that the Phytoplankton community could be divided into 4 distinct groups, indicating rapid changes of the community in the short course of this survey. These phytoplankton groups also showed distinctive dispersion patterns in 2-dimensional canonical space, indicating distinct groupings for stations at each survey. Dominant taxa of diatoms (Chaetoceros curvisetus, Chaetoceros spp., Leptocylindrus danicus, Leptocylindrus mediteraneus, Skeletonema costanum, and Pseudo-nitzschia pungen) clustered in region of CCA space corresponding to stations surveyed at the middle of July. Dominant taxa of dinoflagellates were tightly associated with stations surveyed at the middle (Karenia breve) and end (Cochlodinium polykrikoides and Polykrikos schwartzii) of August. The CCA also showed that the phytoplankton community compositions were highly associated with water temperature, transparency, NO₂, NH₄ and PO₄, suggesting that gradients in physical and nutrient conditions affect short-term changes in phytoplankton composition.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.3
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• pp.290-296
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• 2009

Acoustic technologies are commonly used to estimate biomass and distribution of fisheries resources in coastal areas and the open ocean. The pelagic species of Engraulis japonica, Scomber japonicus and Sardinops melanosticta spawn migrate to the southern part of the Sea of Korea and capture of these three species comprise 50% of the total abundance in Korean waters. Since 1970, anchovy landings have increased to 0.2 million tons in 1990, 0.27 million tons in 2001, and 0.25 million tons in 2003. Acoustic surveys were conducted on 24-26, May and 20-21, June 2005 around the Tongyeong, Geojae, and Namhae anchovy fishing ground using a dual beam echo sounder (DT-5000, 200 kHz Biosonics). Using this approach, information was obtained on the distribution (depth and position) of zooplankton, and adult and juvenile anchovy. We calculated and compared anchovy biomass using simple summation and geostatistic methods to assess the advantages and constraints of the two techniques.

• Journal of Korea Water Resources Association
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• v.55 no.11
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• pp.865-875
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• 2022

Field measurements and numerical simulations using EFDC model were performed to quantify the changes of water circulation near Gusipo coast located in the Yellow Sea of Korea to estimate the impact of the construction of the coastal structures (jetty, groin, Gusipo port and bridge). The model predicted tide and tidal currents agreed reasonably well with the measurements. The maximum currents during spring tide near the Gusipo Beach (GB) have the range of 20~40 cm/sec whereas those off the GB range from 60 to 80 cm/sec. The typical patterns of tidal current show parallel with the local isobath. Tidal currents flow northeastward during the flood tide whereas the currents during the ebb tide flow southwestward. The current speeds at shielded waters after the construction of coastal structures strongly decreased as compared with those before the construction. The tidal volume due to the construction of coastal structures was estimated using the depth averaged velocity for 24 hours of spring tide. Tidal volume after construction of coastal structures was compared with initial state (before construction). Tidal volume at present state (after construction of jetty, groin, Gusipo port and bridge) decreased by 28.4% as compared with that of the initial state. The volume after construction of jetty and groin decreased by 21.3%, and the volume after construction of Gusipo port and bridge decreased by 9.8%.

• Korean Journal of Environmental Biology
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• v.37 no.2
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• pp.164-176
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• 2019

For this study, we carried out a field survey on the analysis for the spatial distributions of phytoplankton community in the eleven areas of the Korean South Sea during the early summer of 2018. The results from the study showed that the phytoplankton community consisted of 56 genera and 105 species showing by diatoms with 52.4%, dinoflagellates with 40.0% and other phytoflagellates with 7.6%. The cell density of the phytoplankton ranged from 5.5 to 593.2 cells mL^-1. The species number and cell density of the phytoplankton were high in the eastern waters of the South Sea and low in the western one. The phytoplankton community showed the characteristics of being dominated by the diatoms except in the Geumpo of Namhae, Ocheon-dong of Yeosu and Oenarodo of Goheung. The dominant species of the phytoplankton community were the centric diatoms, Skeletonema costatum-like species (ls), except for the Ocheon-dong and Chungdo of Wando. However, the Ocheon-dong was dominated by toxic dinoflagellate, Gymnodinium catenatum by 41.1% dominance. On the other hand, Keumpo and Oenarodo was by dinoflagellate, Tripos fusus more than 12% dominance in the surface layer. The spatial distribution of the phytoplankton community in the coastal waters of the Korean South Sea in the early summer were determined by the supply of nutrients through precipitation.

• Journal of Life Science
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• v.18 no.2
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• pp.284-286
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• 2008

Octopus minor (O. minor) is widely distributed along the coastal regions of Korea, but most of them are caught in southern waters which are associated with one of the important fisheries stock. At present, O. minor from China has been introduced to the fishery markets in Korea. Here, we attempt to discriminate their origin for Korea or China using molecular techniques. Based on the O. minor mitochondrial DNA sequence, we developed a PCR-based origin discrimination system. The assay specificity was assessed by testing four individuals of O. minor from Sangdong, China, as well as 20 additional O. minor from Namhae, Muan, Yeosu and Jindo, Korea. Only four isolates of O. minor originated from China tested as positive in our distinction system. All PCR-positive products yielded identical sequences from Chinese O. minor, whereas Korean O. minor appeared to be PCR amplification. This result suggested that the primers used in this study are O. minor species specific, especially originated from China. The detection system appeared to be positive results in the use of 0.1 ng of Chinese O. minor DNA as template, however, the Korean O. minor even using $1{\mu}g$ of DNA showed no amplification. Consequently, the assay provides a simple, rapid and accurate method for the detection of Chinese O. minor.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.3
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• pp.29-41
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• 2012

This study's objective is to inform people of the value and identity and to understand the cultural landscape characteristics of coastal village forest, which have not been studied in-depth in previous studies. This study was conducted by selecting 10 village forest sites in the southern coast of Gyeongsangnam-do, Korea and the present state of forests were investigated through bibliographical and on-the-spot survey, as well as interviews with local villagers. The following points(characteristics of traditional culture, practical characteristics, scenic characteristics) are the important factors for analyzing cultural landscape characteristics of coastal village forest verified through the study. First, The coastal village forest in the village commons is mental space for the local community affected by folk belief rather than confucian backgrounds. Second, The coastal village forest is a reasonable space contriving economic efficiency and solving the real problems facing the coastal village. Third, The coastal village forest identities should be understood the land use around village and behind mountain from the sea of wide range rather than confined to just a forest consisting of trees. This study's significance is to make the basic data and to enhance the value of the coastal village forest unnoticed. In addition, the subjects of the study should be extended to the east and west coastal village forests and subsequent research should be conducted to notification the characteristics and differences of each coastal village forest.