• ALGAE
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• 제37권2호
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• pp.123-133
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• 2022

Genetic diversity and distribution patterns of marine macroalgae are increasingly being documented in Southeast Asia. These studies show that there can be significant levels of genetic diversity and isolation between populations on either side of the Thai-Malay Peninsula. Bostrychia tenellla is a common filamentous red seaweed in the region and the entity is represented by at least two cryptic species. Despite being highly diverse and widespread, genetic variation and population structure of this species complex remains understudied, especially around the Thai-Malay Peninsula. We analyzed genetic diversity and inferred the phylogeographic pattern of specimens identified as B. tenella using the plastid RuBisCo spacer from samples from the Andaman Sea and the Gulf of Thailand. Our genetic analysis confirmed the occurrence of the two cryptic B. tenella species (B and C) along both coasts. Cryptic species B was more common in the area and displayed higher genetic diversity than species C. Historical demographic analyses indicated a stable population for species B, but more recent population expansion for species C. Our analyses also revealed that both cryptic species from the Andaman Sea possessed higher genetic diversity than those of the Gulf of Thailand. We also detected moderate to high levels of gene flow and weak phylogeographic structure of cryptic species B between the two coasts. In contrast, phylogeographic analysis showed genetic differences between populations of both cryptic species within the Andaman Sea. Overall, these results suggest that cryptic B. tenella species around Thai-Malay Peninsula may have undergone different demography histories, and their patterns of genetic diversity and phylogeography were likely caused by geological history and regional sea surface current circulation in the area.

• 한국환경과학회지
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• 제21권12호
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• pp.1477-1485
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• 2012

This study examined urbanization effects and the causes of urbanization, urban population growth, increase of the city scale, land cover change, and human cultures and economic activities, using the daily minimum temperatures of the past 50 years (1961-2010) with the subject of Busan and analyzed correlations between urbanization effects and the causes of urbanization. Thereby, this paper drew a conclusion as below: 1) Due to the urbanization effects, the average annual daily minimum temperature increased as about $1.2^{\circ}C$; however, except for the factor of urbanization, the increase was shown as about $0.2^{\circ}C$. The occupancy of urbanization effects in the total temperature increase was quite high as about 83%. 2) Just like other cities experiencing urbanization, Busan, too, sees population growth and the expansion of city area as well as increased urbanization effects. First of all, correlation between population growth and urbanization effect was high as 0.96 before 1985 while it was lowered as 0.19 after 1985. Also, correlation between the increase of city area and urbanization effect was high as 0.64 and 0.79 before and after 1985. 3) Regarding the correlation between long-term land use change and urbanization effect, urbanization effect was affected greatly by the increase of city area (0.97) and reduction of green area (0.92). 4) Concerning human activities possible to affect the climatic factors of a city, this paper found the following factors: road length, car increase, power use, and the consumer price index, etc. And regarding the correlation between the three factors and urbanization effect, the correlation was higher in the consumer price index (0.97), the number of registered cars (0.89), power use (0.75), and road length (0.58) in order.

• 한국발생생물학회지:발생과생식
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• 제21권4호
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• pp.435-440
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• 2017

The author performed PCR-based genetic platform to measure the hierarchical dendrogram of Euclidean genetic distances of Korean scallop populations (KSP), particularly for Chlamys farreri, which was further compared with those of the Chinese scallop populations (CSP), by employing the with specifically designed oligonucleotide primer sets. The scallop is economically and ecologically very important bivalves in South Korea. Relatively, individuals of KSP population were fairly distantly related to that of CSP population, as shown in the hierarchical dendrogram of Euclidean genetic distances. Comparatively, individuals of KSP population were fairly distantly related to that of CSP population. Thus analysis of genetic difference between scallop populations could provide important statistics for fishery and aquaculture. Overall the results showed specific and/or conserved genetic loci between scallop populations. Information on the genetic distance of the bivalve would be helpful to understand scallop expansion or conservation in the coastal regions of South Korea. Specific markers developed by the author will be useful for the analysis of scallop population genetics and distribution in coastal region.

• 한국수산과학회지
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• 제50권1호
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• pp.65-76
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• 2017

Since the late 1990s, walleye pollock Gadus chalcogrammus fisheries in Korean waters have been considered collapsed. Although many fisheries scientists suspect that the collapse might have been triggered by overexploitation of juvenile pollock or environmental changes, such conjectures have been neither tested nor investigated, partially because of limited data on the population. There has been no survey of the population, and the ages of fish in fishery catch have rarely been identified. Instead, fishery catch data from 1975-1997 included information about two life stages, 'juveniles and adults,' and data on catch-per-unit-effort (CPUE) during 1963-2007 and those on fish length and weight during 1965-2003 had been sporadically collected from commercial fisheries. To test hypotheses about the collapse of the pollock fisheries, we used a statistical linear model with juvenile CPUE as the response variable, and abiotic (e.g., water temperatures) and biotic factors [e.g., adult pollock, flatfishes (Pleuronectidae sp.), and sandfish (Arctoscopus japonicus) CPUEs] as the explanatory variables. The model results indicated that depletion of the pollock population was associated with both biotic (adult pollock and flatfishes abundance) and abiotic factors (mid-water temperatures in February and October). We further interpreted the results from ecological and biological perspectives, suggesting possible mechanisms.

• 수산해양교육연구
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• 제26권1호
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• pp.108-125
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• 2014

Although South Korea had managed fishery resources based on elements included in the fishery like fisheries licence, after agreeing on UN Convention on the law in 1999, it became inevitable to adopt TAC that regulates yield. Therefore, currently operating an indecisive system by maintaining the fisheries license system while applying TAC only to some fisheries. However, it became imperative to find ways to improve the current system as it dose not solve problems such as decrease of fishery resources and catch per unit effort, excessive input of fishing boats, rising costs for fishery management, and shortage of fishery population. For those reasons, it is time to review ITQs, which is recognized globally as the most innovative fisheries management system. To adopt the ITQs, it seems necessary to compare how the fisheries act of New Zealand which is currently most successfully operated and Fisheries Resources Management Act of Korea. To do so, in this study, the provisions on TAC of the two countries are compared to analyze the institutional necessity for Korea to adopt ITQs. The following conclusions have been made : First, it will be necessary to gradually expand the species and fisheries for which TAC is enforced, and accumulate correct data on fisheries resources. Second, while forcing traders to obtain license as well, the species and quantity of traded fisheries must be reported separately for cross-checking with the catch reported by the fisheries. Third, the number of observers must be increased and report the species and quantity of the catch to person in charge at the relevant port, and observers must check the report before disembarkation. Fourth, penalty for violating Fisheries resources management act must be enhanced, especially regarding false report of fishery activities and catch.

• 해양환경안전학회지
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• 제18권3호
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• pp.193-198
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• 2012

겨울철 해표면 수온 및 한국 주변역 생태계의 장기 변화 특성 및 상관관계를 분석하였다. 기후 및 해양환경의 변화와 동반된 어획강도의 변화는 1970 년대 이후 어획량 증가의 주요 원인으로 나타났다. 한국 주변역의 겨울철 SST는 1980년대 후반 기후체제변환 시점을 중심으로 상대적으로 저수온에서 고수온으로 변화되었다. 평균영양단계(MTL)는 1970년대 중반 이후 지속적으로 감소하기 시작하였으며, 하위영양단계 어류의 어획량 증가가 중요 변수로 작용하였다. 통합생태계 기반 자원평가 방법중 한가지인 FIB 지수는 1970년 초부터 1970년 후반까지 증가하였으며, 이후 일정 수준을 유지하였다. 특히, 중간영양단계에 위치하는 멸치와 정어리의 개체수 변화는 1970년대 초 이후 MTL 변화의 주요 인자로 작용하였다.

• 수산경영론집
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• 제52권1호
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• pp.1-22
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• 2021

This study aims to face common threats from the depletion of fish resources, the decline of production and employment as well as the increase of life risk in East Sea Rim countries, North Korea, South Korea, Japan and Russia due to the Chinese fishing fleets entering East Sea. The recent competition in fishing among fishing vessels and fleets of national origin operating in the East Sea has induced a significant change in the ecological landscape of the fishing fleets cluster while having influenced production and employment in the fishing industries of South Korea and Japan as well as life threat on the fishermen in North Korea. It seems that the population organizational ecological theory can be applied to this change. It can be seen as the isomorphism of the selection process over the exclusive economic zone (EEZ) to avoid the environment in which these North Korean fishing vessels are pushed against the Chinese fleet in the North Korean part of the East Sea. To resolve the fishery disputes or conflict in the common waters in East Sea, first of all, Chinese fishing fleets will be required to put international pressure so as to solve the unfairness of the illegal fishing and overfishing by the International Fishery Organization or the UN violations of the sanctions against North Korea selling fishing rights to China. Although it is not easy for South Korea to cooperate with North Korea in the short term, South Korea will be able to support the fishery infrastructure in North Korea in the mid- to the long-term to prevent the loss of innocent lives for their fishermen and to raise their incomes.

• 한국해양학회지:바다
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• 제24권3호
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• pp.448-456
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• 2019

1890년대부터 1900년대에 걸쳐서 일본은 여러 차례 조선의 바다를 조사하였다. 그 조사결과물로는 "조선통어사정"(1893) "조선국원산출장복명서"(1895) "조선수로지"(1894) "조선어업협회순라보고"(1898~1900) "한해통어지침"(1903) "한국수산지"(1908~1911)를 들 수 있다. 비록 이러한 조사들이 100년 이전에 이루어진 것이지만, 당시 조선의 어업 상황은 물론이고 연해지역 주민들의 생활상을 소상히 들여다볼 수 있는 자료이다. 특히 "한국수산지"는 전 4권에 이르는 방대한 분량으로, 연해의 수산물을 비롯하여 조선의 역사와 문화와 관련된 내용도 적지 않다. 특히 연해 마을의 인구, 어업에 종사하는 사람의 수, 어선과 그물 수까지 파악하고 있다. 수산학 발전이라는 관점에서 보면, 이미 린네 이후의 근대적인 수산물 분류법이 적용되고 있으며, 당시의 분류는 현재의 분류와 다른 점도 적지 않아서 동식물 분류학의 관점에서도 흥미로운 자료라고 할 수 있다.

• 농촌의학ㆍ지역보건
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• 제48권4호
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• pp.275-284
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• 2023

Objectives: This study aimed to assess hand grip strength and femoral neck bone mineral density levels among Korean fishery workers and investigate their association. Methods: Hand grip strength and femoral neck bone mineral density were measured in a survey and health examination conducted in 2021 among fishery workers in a southern region of South Korea. Covariates including gender, age, education level, income level, smoking behavior, drinking behavior, family history of hip fractures, use of calcium and vitamin D supplements, hypertension, diabetes, regular exercise, and body mass index were investigated. Multiple regression analysis was employed to assess the association between hand grip strength and femoral neck bone mineral density. Results: Among 147 fishery workers, 8.16% exhibited low hand grip strength levels indicative of possible sarcopenia, and a significant association was found between low hand grip strength and decreased femoral neck bone mineral density (β = -89.14, 95% CI = -160.50, -17.78). Additionally, factors such as women gender, advanced age, family history of hip fractures, and a body mass index below 25 kg/m² were associated with decreased femoral neck bone mineral density. In the subgroup analysis by gender, a correlation between low hand grip strength and decreased femoral neck bone mineral density was observed only in men. Conclusions: Further research is needed to explore various determinants and intervention strategies to prevent musculoskeletal disorders among fishery workers, ultimately enhancing their quality of life and well-being.

• 수산해양기술연구
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• 제8권1호
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• pp.1-13
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• 1972

Yellow croacker, Tseudociaena manchurica Jordan et Thompson in the Yellow Sea and East China Sea are subjected to be caught by trawl nets throughout the year. First indices of population size in every period 8re calculated. Considering present status of the yellow croacker fishery and ecology of the fish, mathematical models must have been established in order to determine catchability coefficient, natural m ortali ty, fishing mortality, recrui ting coefficient of the fish ing ground, and dispersion coefficienl from the fishing ground. The results an, summmarized as follows: Catchabil i ty coefficient $(C) = 2. 2628 {\times} 10^{-5}$ Natural mortality (M)=0.3293 Population for lhe first half season(July 1st to the following January 3lst) Initial population = 14, 621 $/\frac{M}{T}$ Recruitment =45, 597 $/\frac{M}{T}$ Natural mortality = 8, 660 $/\frac{M}{T}$ Final population =42, 970 $/\frac{M}{T}$ Population for the latter 1131f scason(February 1st to June 30th) Initial population = 69, 170 $/\frac{M}{T}$ Dispersion =51, 688 $/\frac{M}{T}$ Natural mortality = 6, 082 $/\frac{M}{T}$ Final population = 1, 802 $/\frac{M}{T}$.