• 제목/요약/키워드: overfishing

검색결과 52건 처리시간 0.026초

중국 고대 수산업의 변화와 발전에 관한 연구

  • 조원일;김종규
    • 중국학논총
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    • 제71호
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    • pp.237-254
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    • 2021
  • It can be said that the fishery industry in ancient China did not originally occupy a very special economic area even when it was started. At that time, the fishery industry was only treated as a means for the livelihood of ordinary people. Over time, the value and economic benefit of aquatic products began to be valued. Its origin can be said to have originated from Yugong(禹貢), which was established by King Yu. These records made it clear that the ancient kings placed great importance on the economic value of seafood and the importance of the fishery industry in the government. Thus, the fishery industry was established as a part of the socio-economic system. In ancient China, the fishery industry was one of the industrial systems that supported traditional Chinese society along with agriculture. It will be possible to analyze the way of thinking of modern Chinese people on the fishery industry through the study of the fishery industry in the traditional era of China. And based on this analysis, I think that it will be able to contribute to a certain extent in establishing a theoretical foundation for countermeasures against the reckless overfishing of fishery resources by Chinese fishermen in the West Sea, which is currently a problem.

Overfishing and recent risk for collapse of fishery in coastal Mediterranean lagoon ecosystem (Karavasta lagoon, southeastern Adriatic sea)

  • Spase Shumka;Yukio Nagahama;Sarjmir Hoxha;Koji Asano
    • Fisheries and Aquatic Sciences
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    • 제26권4호
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    • pp.294-303
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    • 2023
  • Beside that the fish species and their sub-populations are highly important as a keystone species in the coastal and marine ecosystem, there are very few studies on their presence, distribution and temporal variations within and around the lagoon ecosystems in Albania. This paper provides an updated review on the life cycle, fishery, exploitation state and management of the main species that are subject of commercial fishing in the Karavasta lagoon, southeastern Adriatic coast of Albania. Due to the fact that lagoons represent a continuum between continental and marine aquatic ecosystems they play a crucial role in species life cycles. Further on in the circumstances of rapid utilizations and environmental changes, anomalies in salinity and temperatures, accelerated anthropogenic influences their rate of vulnerability is highly increased. Following the requirements of the Water Framework Directive, transitional water, coastal lagoons and estuaries there is a need for urgent monitoring and management approaches. The commercial species include: European eel (Anguilla anguilla), species of Family Mugilidae (Mugil cephalus, Liza ramada, Liza salienes and Chelon labrosus), Seabream (Sparus aurata), Seabass (Dincentrarchus labrax), etc. Fish productivity is oscillating from maximum value of 61.95 kg/ha is recorded in period of 1975-80 and lower value of 31 kg/ha in year 2020. Our study highlights importance of fish and fishery long-term monitoring, and contributes to understand the driving factors in productivity, migration patterns and species ecology in the vital coastal ecosystems.

연근해 어선원 복지 공간 확보를 위한 기초 연구 (A Basic Study on Securing Welfare Space in Crew Accommodation for Fishers Working in Coastal and Inshore Fisheries)

  • 김기선;한세현;조장원
    • 수산해양교육연구
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    • 제29권3호
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    • pp.811-821
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    • 2017
  • This paper intends to propose the direction for improving the welfare space in crew accommodation of fishing vessels engaged in coastal and inshore fishery business in order to solve the phenomenon which young fishers trend to avoid working on fishing vessels. Coastal and inshore fisheries are defined as permitted fisheries business under the Fisheries Act and classified into coastal fisheries and inshore fisheries based on a gross tonnage of 10 tons. Fisheries Act also stipulates the upper limit tonnage regulation and the restrictions on bottoms of fishing vessels permitted for coastal and inshore fisheries to protect fishery resources and to prevent overfishing. It is difficult to increase the welfare space in crew accommodation of fishers under such restrictions because the welfare space in crew accommodation could be secured by reducing the space for the strength of fishing. Therefore, this paper compares the revision trend of the international convention(The Work in Fishing Convention, 2007) and domestic laws on welfare space in crew accommodation of fishing vessels engaged in coastal and inshore fishery business to find out the problems and improvement points in securing the welfare space in crew accommodation of fishing vessels. As a result, it is proposed to revise the Enforcement Ordinance of the Fisheries Act so as to secure the welfare space in crew accommodation of coastal and inshore fishing vessels within the scope of maintaining the maximum allowable tonnage limit regulation by adding an exemption provisions of the restrictions on bottoms of fishing vessels in which case the gross tonnage is increased for securing the spaces for crew accommodation and sanitary facilities of fishers without increasing net tonnage where the bottoms of fishing vessels is increased by renovating or replacing the fishing vessels bigger than the bottoms of fishing vessels permitted within the scope of maintaining the maximum allowable tonnage limit regulation.

가입당 생산액 분석에 의한 한국 해역 참조기 Larimichthys polyactis 자원의 관리 (Management of small yellow croaker stock in Korean waters based on production value-per-recruit analysis)

  • 장창익;이은지;강희중
    • 수산해양기술연구
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    • 제50권4호
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    • pp.467-475
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    • 2014
  • This study was performed to estimate optimum fishing mortality (F) and the age at first capture ($t_c$) for small yellow croaker in Korean waters. We first estimated optimum F and $t_c$ using traditional yield-per-recruit (YPR) analysis, and the results were 0.8/year and 2.5 years old, respectively. However, the individual fish price per unit weight of small yellow croaker in Korea increases dramatically by size. Thus, we developed an alternative method, which is called as production value-per-recruit (PPR) analysis. We developed two types of the PPR analysis, that is, the discrete function and the continuous function method. We estimated optimum F and $t_c$ using the two types of the PPR analysis and compared the results. The optimum F and $t_c$ from the discrete function method, were 0.3/year and 5.0 years old, respectively, while those from the continuous function method were 0.5/year and 3.5 years old, respectively. These PPR estimates were much more conservative for the stock management than the traditional YPR analysis, which can prevent the fish stock from the economic overfishing. As a result, the PPR analysis could be more proper approach for stock assessment in the case that the individual fish price per unit weight increases dramatically by size like small yellow croaker in Korea.

한국 동해 생태계의 잠재생산량 추정방법에 관한 비교 연구 (A comparative study on the estimation methods for the potential yield in the Korean waters of the East Sea)

  • 임정현;서영일;장창익
    • 수산해양기술연구
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    • 제54권2호
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    • pp.124-137
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    • 2018
  • Due to the decrease in coastal productivity and deterioration in the quality of ecosystem which result from the excessive overfishing of fisheries resources and the environmental pollution, fisheries resources in the Korean waters hit the dangerous level in respect of quantity and quality. In order to manage sustainable and effective fisheries resources, it is necessary to suggest the potential yield (PY) for clarifying available fisheries resources in the Korean waters. So far, however, there have been few studies on the estimation methods for PY in Korea. In addition, there have been no studies on the comparative analysis of the estimation methods and the substantial estimation methods for PY targeted for large marine ecosystem (LME) For the reasonable management of fisheries resources, it is necessary to conduct a comprehensive study on the estimation methods for the PY which combines population dynamics and ecosystem dynamics. To reflect the research need, this study conducts a comparative analysis of estimation methods for the PY in the Korean waters of the East Sea to understand the advantages and disadvantages of each method, and suggests the estimation method which considered both population dynamics and ecosystem dynamics to supplement shortcomings of each method. In this study, the maximum entropy (ME) model of the holistic production method (HPM) is considered to be the most reasonable estimation method due to the high reliability of the estimated parameters. The results of this study are expected to be used as significant basic data to provide indicators and reference points for sustainable and reasonable management of fisheries resources.

노르웨이 해역 수산생명자원 관리모델 (The Norwegian Model of Fisheries Bio-Resources Management)

  • 오현택;이원찬;송치문;김형철;김정배;정래홍
    • 한국수산과학회지
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    • 제46권2호
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    • pp.111-118
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    • 2013
  • The Norwegian coastal area is the most efficient region for fishery production in the world's oceans, the Norway is the world's top 10 fisheries countries through efficient fishing and fishing aquaculture technology and its scientific management of fisheries bio-resources, with Norwegian salmon having attained the world's highest level. In the late 1980s, fisheries resources were depleted due to overfishing and fish diseases, resulting in a crisis in the fishing industry that lasted until the early 1990s. Since the national fishery emergency, people involved in the fishing industry, including fishermen, research scientists, and government officers, have tried to overcome the challenges facing the industry and identify an appropriate management model for fisheries bio-resources in the Norwegian coastal area. First, research vessels were used to monitor water and sediment conditions and fishery species, with the long-term aim of predicting fishery resources in real time and collecting information on species diversity, abundance, and distribution. Second, a "Healthy Fish Project" was promoted to counter natural disasters and fish disease problems with the development of vaccines against viruses and bacteria, eventually allowing for a decrease in the use of antibiotics and the production of notably healthier fish in the 2000s. Third, a systematic management model was developed to help with preparations for decreases in the total number of fishermen and increases in the proportion of elderly fishermen in the fishery industry using the development of automatic fishing aquaculture systems and short-chain systems. We could learn from the Norwegian model of fisheries bio-resources, management and could adopt it for the preparation of fishery bio-resources management policy for South Korean coastal areas in the near future.

한국산 참홍어(Raja pulchra)의 다배성 난각 특징과 자어의 형태 (Characteristics of Multi-embryo Egg Capsule and Larvae of Mottled Skate Raja pulchra from Korea)

  • 조현수;강언종;조영록;서형철;임양재;황학진
    • 한국어류학회지
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    • 제22권4호
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    • pp.217-224
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    • 2010
  • 참홍어(Raja pulchra)는 서해지역에서 산업적으로 활용도가 높고 개체군 크기의 축소가 예상되므로 인공증식 기술 개발과 보존을 위해 일련의 연구를 수행하였다. 이 연구는 연중 대형 난각의 형태로 다회 산란하는 특성과 완전한 형태로 부화하는 치어의 특징을 기록하였다. 난소 내 난은 평균 179.8 (54~247)개로 직경이 5가지 무리로 구분되어 순차적인 산란에 기여하는 특성을 보였다. 난각은 다른 홍어류의 종과 구분되는 특징적 구조를 보였으며, 하나의 난각내에 포함되는 배의 수는 2~6개 범위이었다. 아울러 난각내에서 발생하는 자어와 부출 직전에 해당하는 치어의 형태적 특징 및 변화를 분석하여 기술하였다.

Age Structure and Biomass of the Icefish Pseudochaenichthys georgianus Norman (Channichthyidae) Between 1976 and 2009: a Possible Link to Climate Change

  • Traczyk, Ryszard;Meyer-Rochow, Victor Benno
    • Ocean and Polar Research
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    • 제41권4호
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    • pp.233-250
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    • 2019
  • A re-assessment of the age structure of the population of the Antarctic icefish Pseudochaenichthys georgianus based on body length data covering the years 1976-2009 and including larvae and postlarvae collected in 1989 and 1990 allowed us to define age groups 0, I, and II as containing fish with respective body lengths of 6-9 cm, 15-27 cm and 27-39 cm. Age at maturity (first spawning) was found to occur in age group III at body lengths that have been falling from 50.1 cm in 1979 to 45.4 cm in 1992. Considering postlarvae together with adult fish, the v. Bertalanffy growth curve parameters were determined as L = 60.62 cm, k = 0.4, t0 = 0.25. Although the reasons for a maturity at shorter body lengths is not fully understood a host of environmental factors like increasing water temperatures and possibly changes in currents, interspecific competition, food availability, etc. are likely to be involved. Global warming (and not primarily overfishing) is likely to have been responsible for the disappearance of larger fish in the surface waters of South Georgia since 1977, for virtually all commercial fishing stopped in the early 1990s. On the other hand, the appearance of numerous younger spawning individuals suggests that larvae do survive in the colder deeper water below 200 m. The biomass of Ps. georgianus oscillates with a 4-year periodicity in contrast to that of the coexisting icefish Chaenocephalus aceratus: the former with a lower biomass in warm years and a higher one in cold years. The biomass of the third species of icefish in the region, i.e. Champsocephalus gunnari, also oscillates, but with a longer periodicity than that involved in the biology of the other two and its biomass increases in contrast to the other two species. The result is that the biomass all three species considered together is rather stable.

동해 왕돌초 어장의 지속적 이용 및 관리 방안 (Sustainable Utilization and Management Scheme in Wangdol-cho Surrounding Sea Area)

  • 이광남;명정구
    • Ocean and Polar Research
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    • 제25권3호
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    • pp.331-345
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    • 2003
  • The fishing ground surrounding Wangdol-cho is not only overexploited by the littering of dilapidated fishing net and equipment, but also by fishermen's overfishing, surpassing optimum fisheries resources. In addition, increasing fishing efforts (number of fishing vessel and fishing net, etc) contribute to the deterioration of fishing ground, and it is urgently required that schemes to tackle the problems should be taken. To effectively address the problems as such, this paper aims to propose sustainable utilization and management scheme of fishing ground through classification of fishing ground surrounding Wangdol-cho as one area which is less than 50m deep, measuring $13.66km^2$ and the other, permission fishing area of Gill Net fishery, measuring $347.23km^2$. The analysis shows that, for the water area less than 50m deep, implementation from a short-term perspective includes autonomous management fishery by gill net and trap fishery. For the permission fishing area of Gill Net fishery, implementation includes limit on fishing period, real name system of fishing equipment and limit on fishing equipment. Implementation from a medium and long-term perspective includes limit on scuba diving, designation of underwater sightseeing zone, sea farming, facilities of surveillance, adoption of approval system for the permission fishing area of Gill Net fishery and introduction of report system for fishing.

Optimization of Physical Conditions for Caviar Analog Preparation Using Calcium-alginate Gel Capsules

  • Ji, Cheong-Il;Cho, Sueng-Mock;Yun, Young-Soo;Kim, Seon-Bong
    • Fisheries and Aquatic Sciences
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    • 제10권3호
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    • pp.103-112
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    • 2007
  • High prices, overfishing, and contamination have limited the availability of natural caviar as a food product. We attempted to apply encapsulation by calcium-alginate gel membranes to caviar analog preparation in an effort to produce a high-quality replacement for natural caviar. Physical conditions of stirring speed $(X_1,\;rpm)$ and gelation time $(X_2,\;min)$ as the independent variables for gelation were optimized by response surface methodology. Sphericity $(Y_1,\;%)$, diameter $(Y_2,\;mm)$, membrane thickness $(Y_3,\;mm)$, rupture strength $(Y_4,\;g)$, and rupturing deformation $(Y_5,\;mm)$ were used as the dependent variables to compare characteristics of the capsules for caviar analogs with natural caviar. The values of the independent variables as evaluated by multiple response optimization were $X_1=-0.1271 (278 rpm) and $X_2=0.4436$ (12.2 min), respectively. Predicted values of the four dependent variables were $Y_1=97.7%,\;Y_2=2.97mm,\;Y_4=1,465g,\;and\;Y_5=1.15mm$. Membrane thickness $(Y_3)$ was eliminated from the dependent variables for multiple response optimization because it could not be measured with an image analyzer. The experimental values prepared under the optimal conditions for verification nearly coincided with the predicted values and satisfied the conditions of natural caviar.