• Title/Summary/Keyword: the Southern coast

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Phytoplankton Studies In Korean Waters II. Phytoplankton In The Coastal Waters Of Korea (한국해역의 식물플랭크톤에 관한 연구 II. 한국연안수역의 식물플랭크톤)

  • Choe, Sang
    • 한국해양학회지
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    • v.2 no.1_2
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    • pp.1-12
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    • 1967
  • As a part of the primary production in the coastal water of Korea Seas on October-November 1964 and June-July 1965, quantitative phytoplankton materials by the net haul were obtained. This paper deals with a study on the distribution quantity and specific composition of the phytoplankton in the same waters. 76 species of diatoms and 8 species of dinoflagellates in October-November 1964, and 74 species of diatoms and 7 species of dinoflagellates in June-July 1965 were found. In autumn of 1964 and spring of 1965, there occured 90 species of diatoms and 10 species of dinoflagellates, and 60 species of diatoms and 5 species of dinoflagellates were encountered in both seasons. The maximal total quantity of phytoplankton were observed at Pohang (27,844,000 cell/㎥), Ulsan (25,186,000 cells/㎥) and Yosu (12,829,000 cells/㎥) in June-July 1965 and the smallest (16,000 cells/㎥) at Jukbyon in the coast of the Sea of Japan in October-November 1964. The coastal water of Korean Seas, as well as in the primary production study, is divided into four regions by the phytoplankton characters; coastal waters of the Sea of Japan, the east part of the Southern Sea, the west part of the Southern Sea and the Yellow Sea. The coastal waters of the Sea of Japan and the east part of the Southern Sea, in generally, are rich in the phytoplankton. In the coast of the Sea of Japan, species of Chaetoceros and Bacteriastrum prevail and uncommon in species of Coscinodiscus and Rhizosolenia. In the east part of the Southern Sea, on the other hand, uncommon in species of Chaetoceros and Bacteriastrum, and species of Coscinodiscus Rhizosolenia and hemiaulus indicus prevail. The coastal waters of the west part of the Southern Sea and the Yellow sea are both poor in the phytoplankton but Coscinodiscus species prevailed comparatively.

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Geochemical Study of Black Shale in Uhangri Formation, Haenam Area (해남지역(海南地域)에 분포(分布)된 우항리층내(牛項里層內) 흑색(黑色)셰일의 유기지화학적(有機地化學的) 연구(硏究))

  • Lee, Dai Sung;Yun, Hyun Soo
    • Economic and Environmental Geology
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    • v.12 no.4
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    • pp.207-221
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    • 1979
  • The studied area occupies the southern part of Haenam peninsula located in the southwestern corner of Korea. The stratigraphic sequences of the area are grouped into following three units in ascending order. (1) Late Cretaceous sedimentary rocks of Uhangri Formation which consist of the alternative beds of black shales and tuffaceous sediments, Hwangsan acidic fine grained tuffs and Jindo rhyolite flows. (2) Late Cretaceous biotite granite and acidic porphyries which intruded the Late Cretaceous sedimentary rocks. (3) Tertiary(?) pitchstone. The study purposes to delineate any of geochemical aspects on the deposition of the sequences, the average amounts of organic materials and the effect to the maturation of hydrocarbonization which has been occured by the intrusives. Sixty nine black shale samples were collected from Uhangri Formation in the northern and southern coasts of the peninsula. Organic carbons, total extracted organic matters and hydrocarbons were mainly determined by the Soxhlet extraction method, together with C-H-N elemental analyses. Based on the field and laboratory studies, the following interpretations have been obtained. (1) The paleohydrostatic condition of the sedimentation which took place was relatively calm and stable to delineate a lacustrine environment. (2) The amounts of organic material were more or less constant throughout the period of the deposition of the sediments. (3) The degree of hydrocarbonization of the Uhangri Formation in the northern coast was taken place higher than that in the southern coast due to the differences of thermal effect by the biotite granite which is assumed to be as a heat source in the area. Among the northern coast, some black shales in Uhangri and Mogsam areas which had been under the most moderate temperature environment snow symptomatic oily material, whereas, those in Sinseongri area do not, which were presumably to be intensive thermal alteration by the later acidic porphyries.

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Climate-related range shifts of Ardisia japonica in the Korean Peninsula: a role of dispersal capacity

  • Park, Seon Uk;Koo, Kyung Ah;Seo, Changwan;Hong, Seungbum
    • Journal of Ecology and Environment
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    • v.41 no.11
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    • pp.310-317
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    • 2017
  • Background: Many studies about climate-related range shift of plants have focused on understanding the relationship between climatic factors and plant distributions. However, consideration of adaptation factors, such as dispersal and plant physiological processes, is necessary for a more accurate prediction. This study predicted the future distribution of marlberry (Ardisia japonica), a warm-adapted evergreen broadleaved shrub, under climate change in relation to the dispersal ability that is determined by elapsed time for the first seed production. Results: We introduced climate change data under four representative concentration pathway (RCP 2.6, 4.5, 6.0, and 8.5) scenarios from five different global circulation models (GCMs) to simulate the future distributions (2041~2060) of marlberry. Using these 20 different climate data, ensemble forecasts were produced by averaging the future distributions of marlberry in order to minimize the model uncertainties. Then, a dispersal-limited function was applied to the ensemble forecast in order to exam the impact of dispersal capacity on future marlberry distributions. In the dispersal-limited function, elapsed time for the first seed production and possible dispersal distances define the dispersal capacity. The results showed that the current suitable habitats of marlberry expanded toward central coast and southern inland area from the current southern and mid-eastern coast area in Korea. However, given the dispersal-limited function, this experiment showed lower expansions to the central coast area and southern inland area. Conclusions: This study well explains the importance of dispersal capacity in the prediction of future marlberry distribution and can be used as basic information in understanding the climate change effects on the future distributions of Ardisia japonica.

Characteristics of Changes in Species Composition with Water Temperature in Set Net Fishing on the Southern Coast of the East Sea (동해 남부 연안 정치망어업의 수온에 따른 종조성 변동 특성 연구)

  • Song, Hyejin;Song, Young Sun;Hwang, Kangseok;Sohn, Dongwha
    • 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.

Growth Rate and Annual Production of Halo-phyte (Suaeda japonica) on Tidal Mud-flat, Southern Part of Ganghwa-Isl, Korea (강화 남부 조간대에 서식하는 칠면초(Suaeda japonica)의 연간 생장 및 생산 양상)

  • Hwang, Ji-won;Lee, Kyun-Woo;Park, Heung-sik
    • Ocean and Polar Research
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    • v.44 no.2
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    • pp.127-137
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    • 2022
  • This study examined the growth pattern and environmental factors affecting the growth of the halophyte, Suaeda japonica, which is prevalent on tidal flats in the west coast of Korea in order to calculate annual carbon production. Quantitative sampling was conducted every month for three years from 2018 to 2020 on salt marshes located on the southern coast of Ganghwa Island. In terms of annual density affected by the germination rate at first period, especially when air temperature for winter time was constantly below 0℃ for long periods of time, germination decreased and precipitation in summer also exerted an influence. In terms of annual growth with regard to length, the part below the ground grew rapidly in the beginning after budding, while the part above ground grew at a relatively steady rate at all times. With regard to biomass, the part below the ground also increased from April in a manner similar to length growth, but decreased drastically from September with leaves falling off and water loss occurring. The part above ground showed a rapid increase from the beginning of the rainy season. Size-frequency distribution revealed broader patterns after the rainy season as individual growth varied, but from September, it stopped at all year. High growth rates were recorded in the initial phase of growth after budding and growth was rapid, but growth declined in summer when biomass increased. The annual mean production based on growth rate was calculated at 352 gDWt/m2/yr, and the highest production was 519 gDWt/m2/yr in 2018, but it has decreased since 2019. Annual carbon production was at calculated 143.41 gC/m2/yr for Suaeda japonica in the vicinity of the southern coast of Ganghwa Island.

First Record of Ulva pertusa Kjellman (Ulvales, Chlorophyta) in the Pacific Coast of Mexico

  • Aguilar-Rosasl, Racal;Aguilar-Rosas, Luis E.;Shimada, Satoshi
    • ALGAE
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    • v.23 no.3
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    • pp.201-207
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    • 2008
  • Based on samplings during 2006-2007 on the intertidal zone of Playa Tampico, Eréndira and Punta Baja, Baja California, Ulva pertusa Kjellman (Ulvales, Chlorophyta) was recorded for the first time for the Pacific coast of Mexico. An alga native to Asia, U. pertusa has just recently been recorded in the southern coast of California (USA). The identification of U. pertusa was based on the observation of the morphology and reproductive characters of the collected specimens. Furthermore, the species identity was confirmed by molecular comparison between nuclearencoded ITS2 sequences of the Mexican samples and those of other Ulva species in GenBnak data. Habitat and distribution of U. pertusa along the Pacific coast of North America are also described. Considering our new report of its occurrence in Mexico, we conclude that U. pertusa is expanding its geographical distribution by trans-ocean introductions.

A Study on the Evaluation and Research Status Analysis of Shellfish Farming in Southern Coast of Korea (남해안 패류양식 주요 품종에 대한 기술수준 평가와 연구 현황 분석)

  • Lee, Dong-Ho;Moon, Seong-Ju;Kang, Jong-Ho
    • The Journal of Fisheries Business Administration
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    • v.50 no.2
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    • pp.57-74
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    • 2019
  • This study is aimed to evaluate the technology levels of shellfish farming in southern coast of Korea and status analysis on research of shellfish aquaculture. With achieving these objectives, it will be possible to present the direction of shellfish farming research and related project. Five major breed of shellfish aquaculture that would be adaptive and sustainable were proposed through consultation and agreement with professional group with more than 15 years of working experience. Moreover also evaluated that levels of technology, industry and market are also evaluated. The evaluation result of the expert group showed that the shellfish farming level occupied the third place in comparison with the US, Japan, Europe, and China. It is estimated that about 13~14 years will reach the level of the highest on average. In addition, most countries are expected to grow by about 10% on average over the next five years. Based on the result of the analysis of 670 research projects (2008~2017), there was little research on climate change and shellfish aquaculture. Besides some of shellfish have not been studied since 2008 and 2013, so it can be mentioned as a future task to be overcome.

Monthly Changes of Marine Benthic Algae and Community Structure at Gahakri, Southern Coast of Korea (한국 남해안 가학리의 해조류와 군집구조의 월별변화)

  • Oh Byoung Geon;Lee Jae Wan;Lee Hae Bok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.1
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    • pp.64-70
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    • 2002
  • The marine algal flora and community structure of Gahakri in Jindo Gun, southern coast of Korea, was investigated monthly during September, 1993-August, 1994. As the results, a total of 87 species including 11 greens, 15 browns and 61 reds was identified. The marine algal flora was classified as the mixed flora based on the species composition. The dominant species of algal community throughout the year was Gloiopeltis furcata, and the subdominants were Sargassum thunbegii, Ulva pertusa and Hizikia fusiformis. In their vertical distribution, the species of algal community distributed yearly (or seasonally) from upper to lower intertidal zones were Gloiopeltis furcata-Corallina pilulifera, Myelophycus simplex, Gloiopeltis tenax (May$\~$October), Dumontia simplex, Sargassum thunbergii-Hizikia fusifomis, Ulva pertusa, Chondracanthus intemedius, Carpopeltis affinis.

Improvement of Marine Environmental Impact Assessment for Golf Course Projects in Southern Coastal Area of Korea (남해연안 골프장조성에 따른 해양환경영향평가 개선방안)

  • Kim, Gui-Young;Lee, Dae-In;Yu, Jun;Eom, Ki-Hyuk;Jeon, Kyeong-Am
    • Journal of Environmental Impact Assessment
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    • v.19 no.5
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    • pp.453-464
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    • 2010
  • We evaluated the status and problems of golf course developments in the southern coast of Korea. It's adjacent waters supports nursery and fishing grounds for commercially-important fisheries species, and various sites are designated and protected as marine protection area(MPA), fisheries reserve, or clean area(blue belt) for producing shellfish. We proposed key assessment items for environmental impact assessment(EIA) and checklists in selecting golf course locations. For the protected areas, we suggest that it is essential to limit golf course establishment while setting a minimal distance from the coast to secure a buffer zone for mitigating the environmental impacts. To efficiently utilize existing regional coastal management plans, it is necessary to diagnose how a golf course development will potentially modify geomorphology and scenery, amplify pollutant loads from non-point sources, and disrupt the functions of coastal ecosystem. Especially, continued monitoring and assesssing input loads of hazardous materials originating from agricultural chemicals should be obligatory. Finally, measures for improving the QA/QC analysis were discussed to enhance reliability of environmental data with respect to golf courses and adjacent coastal waters.

Seasonal Occurrence of Tobacco Cutworm, Spodoptera litura Fabricius and Beet Armyworm, Spodoptera exigua Hübner Using Sex Pheromone Traps at Different Locations and Regions in Yeongnam District (영남지방 지역 및 지대별 담배거세미나방과 파밤나방 성충의 발생소장)

  • Bae, Soon-Do;Kim, Hyun-Ju;Lee, Geon-Hwi;Park, Sung-Tae
    • Korean journal of applied entomology
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    • v.46 no.1 s.145
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    • pp.27-35
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    • 2007
  • Seasonal occurrences of tobacco cutworm, Spodoptera litura and beet armyworm, Spodoptera exigua were observed using sex pheromone traps at different locations and climatic regions in Yeongnam district. In Gyeongnam province, S. litura male adults kept occur from mid or late March to mid or late November Whereas in Gyeongbuk province, S. litura occurred from mid or late April to early or mid November with exception at Uljin where it was late May to late October. According to the climatic regions, the peak occurrence of S. litura was middle September at the southern coast region, late August at the inland and the basin region, middle August at the inland mountainous region, and early September at the eastern middle coast region. The occurrence rate of S. litura was the highest at Jinju with 20.0% and the lowest at Changyeong with 8.6% in Cyeongnam province, while it was the highest at Sungju with 3.3% and the lowest at Uljin with 0.8% in Gyeongbuk province. In accordance with the climatic regions, the occurrence rate of S. litura was the highest at the inland region with 43.7%, and followed by the southern coast region (36.3%), the basin region (8.4%) and the inland mountainous region (7.0%), and was the lowest at the eastern middle coast legion with 4.6%. On the other hand, S. exigua occurred from early March to middle November with the exception of the eastern middle coast region including Pohang, Yeongdeog and U]ien in Cyeongbuk province where it occurred from mfd April to middle November. The peak occurrence of s. exigua was early August at the inland region, the basin region and the inland mountainous region, and was late of August at the southern coast region and the eastern middle coast region. The occurrence of S. exigua was the highest at Changyeong with 1.6% and the lowest at Busan with 0.4% in Gyeongnam province, while it was the highest at Sungju with 37.2% and the lowest at Uljin with 2.7% in Gyeongbuk province. The climatic regional occurrence rate of S. exigua was the highest at the basin region with 54.3%, and followed by the inland mountainous region (29.9%), the eastern middle coast region (9.3%) and the inland (3.9%), and was the lowest at the southern coast region with 2.6%. As a whole, S. litura occurred more in Gyeongnam province than Cyeongbuk province, while S. exigua occurred more in Gyeongbuk province than Gyeongnam province. According to the regions grouped by climatic differences, the occurrence of S. litura and S. exigua was the highest at the inland region in Gyeongnam province and at the basin region in Gyeongbuk province. The total number of S. litura captured by sex pheromone trap was 2.4 times higher than that of S. exigua. However, the first occurring time and the peak occurrence of S. exigua were slightly earlier than those of S. litura.