• The Korean Journal of Ecology
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• 제22권6호
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• pp.317-324
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• 1999

A research on the coastal mantle communities in South Korea and Japan was carried out. This study was accomplished by using syntaxa and hierarchical system of the coastal mantle communities in South Korea and Japan in terms of the Zurich-Montpellier School's method. The coastal mantle communities in South Korea and Japan are included in the Rosetalia rugosae of northern type and the Viticetea rotundifoliae of southern type, which are characterized by Rosa rugosa and Vitex rotundifolia, respectively. The coastal mantle communities in South Korea are subordinated and are considerably corresponded to those which already identified in Japan. Each syntaxon of the coastal mantle communities in South Korea and Japan is briefly characterized floristically and ecologically, and their distribution is shown on maps.

• The Korean Journal of Ecology
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• 제23권3호
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• pp.193-199
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• 2000

우리나라의 해안사구에 분포하고 있는 해안임연군락의 분포특성에 관한 연구가 수행되었다. 본 연구는 전추정법에 의해 이미 추출된 우리나라 해안임연군락의 단위식생 및 식물사회학적 체계를 토대로 이루어졌으며, 분류된 각 단위식생들에 대한 분포특성 분석은 각 단위식생으로 합성된 조사구의 위도와 온도를 이용하여 수행되었다. 우리나라 해안임연군락의 분포는 해당화군락, 순비기나무군락, 순비기나무-해란초군집, 순비기나무-돌가시나무군집 및 순비기나무-띠군집의 순으로 북쪽에서 남쪽으로 분포하고 있으며, 각 단위식생들의 연속 분포와 중첩 분포의 경향성이 인정되었다. 그리고 한반도의 해안임연군락에 대한 분포유형 결정은 일본, 북한 및 중국의 해안임연식생에 대한 식생학적, 지리적 및 생물기후학적 정보가 필수적인 것으로 판단되었다.

• 수산해양기술연구
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• 제49권3호
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• pp.200-207
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• 2013

This paper presents the mesh selectivity of a net pot for common octopus Octopus minor for the sustainable resources management of common octopus. The filed experiments were carried out the total 10 times in the southern part of coastal sea in Korea from March to May in 2010 using net pots of five different mesh sizes (16, 18, 20, 22 and 26mm). The test of size selectivity, indicated a 50% selection value on the logistic master curve of 3.195, whereby 50% of individuals with a mantle size of approximately 70.3mm selected a mesh size of 22mm. Considering that 50% of common octopus entering sexual maturity have a mantle size of 70.6mm, the optimum mesh size should be equal to, or larger than 22mm.

• The Korean Journal of Ecology
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• 제24권5호
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• pp.267-271
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• 2001

동북아시아 냉온대림역의 해안사구에 발달하고 있는 해안사구임연식생인 해당화군목의 군락체계에 대한 식생학적 연구가 수행되었다. 현재 해당화군목은 동북아시아 임연식생의 최상위 계급인 찔레꽃군강에 귀속되어 있으나, 군락체계적으로 애매한 문제점을 내포하고 있는 실정이다. 본 연구는 찔레꽃군강과 해당화 군목의 식물사회학적 군락체계 및 한국과 일본의 해안사구에서 조사된 해당화군목 197개의 균질한 releve를 이용하여 수행되었다. 해당화군목의 군락체계 분석에는 상재도, 빈도 및 순기여도가 이용되었다. 해당화군목은 그 상급단위로 결정되어 있는 찔레꽃군강과는 명확히 구분되어 해당화군목의 찔레꽃군강으로의 예속은 부적절하였다 따라서, 해당화군목의 식생학적 군락체계는 재고되어야할 것으로 생각되며, 그것은 난온대형 해안사구관목식생을 특징짓는 순비기나무군강에 대응되는 군락유형으로 판단된다.

• 수산해양기술연구
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• 제58권2호
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• pp.113-120
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• 2022

The purpose of this study is to provide information about annual variations in catch size and changes in reproductive biology in the common octopus, Octopus vulgaris, a commercially important species in Jeju Island. Samples were collected from coastal waters of Jeju Island, Korea by coastal trap fishery from January to November 2021. Octopus vulgaris have been decreasing in this region since 1984. The mantle length (ML) ranged from 4.5 to 17.8 cm and body weight (BW) ranged form 88.5 to 2,657.5 g. A χ²-test revealed that the number of males was significantly greater than females (χ² = 32.712, df = 10, P<0.05). Mature females were found from January to July and male occurred January to August. The gonadosomatic index value was higher from July to August than other months. The relationship between mantle length and body weight was BW = 2.4527ML^2.3139 (female) and BW = 2.6785ML^2.3159 (male). At 50% group maturity, female and male average weight was estimated to be 554.7 g and 330.6 g, respectively.

• 수산해양기술연구
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• 제57권3호
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• pp.185-193
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• 2021

This study was conducted to evaluate the performance of the octopus pot according to mesh sizes. Entering behavior of Octopus minor and bait (Macrophthalmus japonicus) escape rate on the mesh sizes of the pots were investigated for six times in indoor tank. The sea trials for evaluating the performance of Octopus minor pot to different mesh sizes (22, 20 and 18 mm) were conducted for six times from 2017 to 2018 in the coastal sea of Deukyang Bay, the Republic of Korea. Behavior patterns of contact pot to leaved pot were more frequent than contact pot to bait search. When the octopus contacted to the pot, there was no clear search behavior to distinguish the mesh sizes. Total catch of 46% was accounted for 18 mm pots, followed by 34% at 20 mm and 20% at 22 mm (P < 0.05). Catch per unit effort was calculated as 30 g/pot at 22 mm, 44 g/pot at 20 mm and 59 g/pot at 18 mm. As a result of evaluating 50% selection of mantle length and weight on the mesh sizes, mantle length (mm) and weight (g) were 84.6 and 147.8 in 22 mm, followed by 20 and 18 mm.

• Journal of Ecology and Environment
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• 제36권4호
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• pp.407-419
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• 2013

Cyclotella species were collected at 51 sites from July 2010 to June 2013 in Korean coastal waters. A total of five Cyclotella species (C. atomus var. marina, C. baltica, C. litoralis, C. meduanae, and C. meneghiniana) were identified in this study. The diagnostic characteristics for five Cyclotella species are described, focusing on the spacing, position, number of satellite pores of the mantle fultoportula and valve face fultoportula. In addition, we put the salinity ranges of five species of Cyclotella together. Of the five Cyclotella species, C. baltica, C. litoralis and C. meduanae are newly recorded in Korea.

• 한국패류학회지
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• 제20권2호
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• pp.155-157
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• 2004

The true cuttlefishes genus Sepia (Doratosepion) Linne, 1758, characterized by shell thick, entirely calcareous, shell almost as long as mantle, was collected from the coastal of Dong-Am, Busan, Korea in April, 2004. The specimen agreed closely with description of Sepia (Doratosepion) kobiensis Hoyle, 1885 and S. tokioensis Ortmann, 1888. We herein described the species, being as the first record of S. kobiensis and tokioensis from the region. New Korean names are also provided.

• 한국수산과학회지
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• 제53권1호
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• pp.57-66
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• 2020

The purpose of this study was to provide information about annual variations in catch size and changes in reproductive biology in the common octopus Octopus vulgaris, a commercially important species. Samples were collected from coastal waters off Gyeongnam, Korea, by coastal trap and coastal complex fishery from February to December 2018. Octopus vulgaris have been decreasing in this region since 2007 and catch prices have been increasing. The mantle length (ML) of O. vulgaris ranged from 1.2 to 21.2 cm and body weight ranged from 42.6 to 5,537 g. The sex ratio differed significantly from what was expected, at 0.45:0.55 (P<0.05). Mature females were found from February to December, except in October and November, and males occurred from February to December, except in October. The gonadosomatic index value was higher from May to September than in other months. The total number of eggs in fecund individuals ranged from 40,280 in 578.1 g of body weight to 138,994 in 1,666.5 g of body weight. The relationship between body weight and fecundity was F=76.486BW^1.0087 (r²=0.7897). At 50% group maturity, average weight was estimated to be 636.35 g, while it was 969.30 g at 75% maturity and 1736.55 g at 97.5% maturity. This study highlights changes in catch size and reproductive biology between 2007 and 2018. These results provide basic evidence that may be used to establish regulatory policy for O. vulgaris fisheries.

• The Korean Journal of Ecology
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• 제18권3호
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• pp.307-321
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• 1995

Division of ecoregions having respective functions was attempted through quantitative and qualitative analysis on vegetation diversity, and heterogeneity and on soil environment of the study sites. Field research was carried out in a square of 81 ㎢ around Andongpo (126°38'E, 37°30'N), Kimpo-gun, Kyonggi provice. Conventional methods applied are as follows: classical syntaxonomy by the Zurich-Montpellier School, interpolation method to determine the degree of diversity, heterogeneity and distribution pattern of vegetation, and correlation analysis between soil properties and plant communities. 41 plant communities were identified and composed of 6 forests, 4 mantle and 31 herb communities including 6 saltmarsh plant communities. In a mesh, number of plant communities was highly correlated to the number of species. The highest number of plant community and species was 25 communities·km-2·mesh-1 and 381 species· km-2·mesh-1 ,and the highest value of vegetation heterogeneity was 28.1 species· community-1·mesh-1. Their lowest numbers were 4 communities·km-2·mesh-1. and 28 species·km-2·mesh-1. and 7 species·community-1·mesh-1, respectively. Contour map on vegetation diversity and heterogeneity enabled us to establish two regions; coastal and inland vegetation. Isoline 〔150〕,〔10〕and〔10〕and〔15〕on the species diversity, the community diversity and the vegetation heterogeneity, respectively, were regarded as ecolines in the study area. Cl- content was recognized as the most important factor from correlation analysis between soil properties. Ordination of sites indicated that the study area be divided into two edaphic types: inland and coastal habitats. It was considered that the extent of desalinization in soil played a major role in determining the species composition in the reclamed area. By matching edaphic division of habitats with division of vegetation structures, designation of ecoregion was endorsed. The approach of current study was suggested as an effective tool to implement an assessment of the vegetation dynamics by the disparity of natural environment and anthropogenic interferences.