• Title/Summary/Keyword: fisheries Management

Search Result 1,919, Processing Time 0.033 seconds

One unusual species, Coilia sp. (Engraulidae, Pisces) from the Yellow Sea

  • Kwun, Hyuck-Joon;Kim, Yeong-Hye;Kim, Jong-Bin;Jeong, Choong-Hoon;Kim, Jin-Koo
    • Animal cells and systems
    • /
    • v.14 no.2
    • /
    • pp.137-145
    • /
    • 2010
  • Four specimens of unknown Coilia sp. were collected for the first time from the Yellow Sea in 2008 and compared with Coilia mystus and Coilia nasus. Coilia sp. showed similar morphology to C. mystus and C. nasus, but differed in that its tail was considerably shorter. We conducted an analysis of the morphological and genetic characteristics in an effort to clarify the taxonomic position of Coilia sp. In counts and measurements, Coilia sp. were well distinguished from C. nasus by the number of scutes (42-44 in Coilia sp. vs. 40-45 in C. mystus vs. 45-55 in C. nasus), ratio of dorsal base length to head length (43.4-47.6 vs. 37.9-47.6 vs. 33.0-41.0), and eye length to head length (19.2-20.8 vs. 17.0-22.4 vs. 13.8-18.2). In caudal skeleton of Coilia sp., urostyle, hypural and epural bones were not observed; instead of them, caudal fin rays were supported by the last vertebra, neural and haemal spines' extension. The molecular phylogenetic relationship was analyzed using 414 base-pair 12S rRNA mitochondrial DNA sequences. The Kimura-2-parameter distance between Coilia sp. and C. mystus was 0.3%, but was 1.3% between Coilia sp. and C. nasus. Both the neighbor-joining tree and maximum-likelihood tree showed that Coilia sp. are closely clustered with C. mystus. Therefore, our results suggest that the Coilia sp. may be a deformed fish of C. mystus.

A Study on Korean Seafarer's Perceptions Towards Unmanned Ships (무인화 선박에 대한 한국 선원들의 인식에 관한 연구)

  • D'agostini, Enrico;Ryoo, Dong-Keun;Jo, So-Hyun
    • Journal of Navigation and Port Research
    • /
    • v.41 no.6
    • /
    • pp.381-388
    • /
    • 2017
  • Recently, renewed attention for technological applications within the maritime industry has taken place, particularly regarding unmanned vessels. There has been a lot of interest about the number of projects aiming at testing the operational feasibility of unmanned vessels, particularly in relation to technological, safety and security issues. Nevertheless, no studies have investigated this issue from the point of view of seafarers towards unmanned vessels; this paper aims at filling this gap. Data has been collected through a survey questionnaire. A Pearson correlational coefficient has been used to test the correlation between some of the variables. The results show that more than half of the respondents indicated that unmanned vessels do not contribute to an increase in accidents at sea. In addition, seafarers believe unmanned vessels will not be operational in the near future, with most of the respondents indicating a 10-20 year time frame. Thirdly, most of the respondents(both officers and ratings).

Climate Change Vulnerability Assessment in Rural Areas - Case study in Seocheon - (농촌지역 기후변화 취약성 평가에 관한 연구 - 서천군을 대상으로 -)

  • Lee, Gyeongjin;Cha, Jungwoo
    • Journal of Korean Society of Rural Planning
    • /
    • v.20 no.4
    • /
    • pp.145-155
    • /
    • 2014
  • Since greenhouse gas emissions increase continuously, the authorities have needed climate change countermeasure for adapting the acceleration of climate change damages. According to "Framework Act on Low Carbon, Green Growth", Korean local governments should have established the implementation plan of climate change adaptation. These guidelines which is the implementation plan of climate change adaptation should be established countermeasure in 7 fields such as Health, Digester/Catastrophe, Agriculture, Forest, Ecosystem, Water Management and Marine/Fisheries. Basically the Korean local governments expose vulnerable financial condition, therefore the authorities might be assessed the vulnerability by local regions and fields, in order to establish an efficient implementation plan of climate change adaptation. Based on this concepts, this research used 3 methods which are LCCGIS, questionnaire survey analysis and analysis of existing data for the multiphasic vulnerable assessment. This study was verified the correlation among 7 elements of climate change vulnerability by 3 analysis methods, in order to respond climate change vulnerability in rural areas, Seocheon-gun. If the regions were evaluated as a vulnerable area by two or more evaluation methods in the results of 3 methods' comparison and evaluation, those areas were selected by vulnerable area. As a result, the vulnerable area of heavy rain and flood was Janghang-eup and Maseo-myeon, the vulnerable area of typhoon was Janghang-eup, Masan-myeon and Seo-myeon. 3 regions (i.e. Janghang-eup, Biin-myeon, Seo-myeon) were vulnerable to coastal flooding, moreover Masan-myeon, Pangyo-myeon and Biin-myeon exposed to vulnerability of landslide. In addition, Pangyo-myeon, Biin-myeon and Masan-myeon was evaluated vulnerable to forest fire, as well as the 3 sites; Masan-myeon, Masan-myeon and Pangyo-myeon was identified vulnerable to ecosystem. Lastly, 3 regions (i.e. Janghang-eup, Masan-myeon and Masan-myeon) showed vulnerable to flood control, additionally Janghang-eup and Seo-myeon was vulnerable to water supply. However, all region was evaluated vulnerable to water quality separately. In a nutshell this paper aims at deriving regions which expose climate change vulnerabilities by multiphasic vulnerable assessment of climate change, and comparing-evaluating the assessments.

A Study on the Simmulation Image Evaluation for the Landscape Improvement of Horticultural Complex in Rural Area (시설원예단지 경관개선 시뮬레이션 이미지 평가 연구)

  • Son, Jin Kwan;Park, Min Jung;Lee, Tae Suck;Kang, Tae Gyoung;Jin, Yu Jung;Kang, Dong Hyeon;Kong, Min Jae
    • Journal of Korean Society of Rural Planning
    • /
    • v.26 no.4
    • /
    • pp.1-13
    • /
    • 2020
  • This study was aimed at improving the landscape agricultural facilities. Agricultural production spaces such as rice paddies and fields are a representative landscape of rural areas. These landscapes should be aesthetically presentable and as such, they require proper landscape planning and management. However, the construction of infrastructure in these landscapes presents environmental and ecological problems. As a result, the unique aesthetics in landscapes such as rice paddies is disrupted by infrastructure development. The construction of infrastructural complexes takes away the pleasantness of the natural landscape. Photographic slides were variable elements were systematically removed in the landscape were used. The original plan and its alternatives (1, 2, 3, 4) in the BV, JV, JG, and GG regions were evaluated using the Likert scale and AHP methods. Statistical analysis was conducted using ANOVA. The results indicate that the removal of variable elements, expansion of separation distance, and the planting of green plants had a positive effect on all parameters. Improvement of landscapes containing infrastructural complexes can be achieved by the use of image simulation.

Impacts of Managing Water in a Closed Basin: A Study of the Walker River Basin, Nevada, USA

  • Tracy, John C.
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2012.05a
    • /
    • pp.1-10
    • /
    • 2012
  • Throughout much of the world, many ecological problems have arisen in watersheds where a significant portion of stream flows are diverted to support agriculture production. Within endorheic watersheds (watersheds whose terminus is a terminal lake) these problems are magnified due to the cumulative effect that reduced stream flows have on the condition of the lake at the stream's terminus. Within an endorheic watershed, any diversion of stream flows will cause an imbalance in the terminal lake's water balance, causing the lake to transition to a new equilibrium level that has a smaller volume and surface area. However, the total mass of Total Dissolved Solids within the lake will continue to grow; resulting in a significant increase in the lake's TDS concentration over time. The ecological consequences of increased TDS concentrations can be as limited as the intermittent disruption of productive fisheries, or as drastic as a complete collapse of a lake's ecosystem. A watershed where increasing TDS concentrations have reached critical levels is the Walker Lake watershed, located on the eastern slope of the central Sierra Nevada range in Nevada, USA. The watershed has an area of 10,400 sq. km, with average annual headwater flows and stream flow diversions of 376 million $m^3/yr$ and 370 million $m^3/yr$, respectively. These diversions have resulted in the volume of Walker Lake decreasing from 11.1 billion m3 in 1882 to less than 2.0 billion $m^3$ at the present time. The resulting rise in TDS concentration has been from 2,560 mg/l in 1882 to nearly 15,000 mg/l at the current time. Changes in water management practices over the last century, as well as climate change, have contributed to this problem in varying degrees. These changes include the construction of reservoirs in the 1920s, the pumpage of shallow groundwater for irrigation in the 1960s and the implementation of high efficiency agricultural practices in the 1980s. This paper will examine the impacts that each of these actions, along with changes in the region's climate, has had on stream flow in the Walker River, and ultimately the TDS concentration in Walker Lake.

  • PDF

Methanogenesis and Methane Oxidation in Paddy Fields under Organic Fertilization

  • Kim, Chungwoo;Walitang, Denver I.;Sa, Tongmin
    • Korean Journal of Environmental Agriculture
    • /
    • v.40 no.4
    • /
    • pp.295-312
    • /
    • 2021
  • BACKGROUND: Global warming is one of the most pressing environmental issues which concomitantly complicates global climate change. Methane emission is a balance between methanogenesis and methane consumption, both of which are driven by microbial actions in different ecosystems producing methane, one of the major greenhouse gases. Paddy fields are major sources of anthropogenic methane emissions and could be compounded by organic fertilization. METHODS AND RESULTS: Literature reviews were conducted to give an overview of the global warming conditions and to present the relationship of carbon and methane to greenhouse gas emissions, and the need to understand the underlying processes of methane emission. A more extensive review was done from studies on methane emission in paddy fields under organic fertilization with greater emphasis on long term amendments. Changes in paddy soils due to organic fertilization include alterations of the physicochemical properties and changes in biological components. There are diverse phylogenetic groups of methanogens and methane oxidizing bacteria involved in methane emission. Also, multiple factors influence methanogenesis and methane oxidation in rice paddy fields under organic fertilization and they should be greatly considered when developing mitigating steps in methane emission in paddy fields especially under long term organic fertilization. CONCLUSION(S): This review showed that organic fertilization, particularly for long term management practices, influenced both physicochemical and biological components of the paddy fields which could ultimately affect methanogenesis, methane oxidation, and methane emission. Understanding interrelated factors affecting methane emission helps create ways to mitigate their impact on global warming and climate change.

Genetic diversity analysis of high yielding rice (Oryza sativa) varieties cultivated in Bangladesh

  • Epe, Isma Akter;Bir, Md. Shahidul Haque;Choudhury, Abul Kashem;Khatun, Asma;Aktar, Most Mohshina;Arefin, Md. Shamsul;Islam, Mohammed Aminul;Park, Kee Woong
    • Korean Journal of Agricultural Science
    • /
    • v.48 no.2
    • /
    • pp.283-297
    • /
    • 2021
  • Investigation of genetic diversity and molecular characterization in high yielding rice varieties is important for their identification. The experiment was conducted during 2016 - 2017 to analyse the genetic diversity of fifteen high yielding rice varieties in Bangladesh by using random amplification of polymorphic DNA (RAPD) markers. Polymorphism was revealed in 12 RAPD primers out of 30, whereas no other reaction was detected on the remaining 18 primers. The 40 out of 45 bands (88.89%) polymorphics were produced by the primers and ranged from 50 to 100%. The maximum number of polymorphic bands was produced by the primer OPB-18 whereas the lowest number of polymorphic bands belonged to OPC-12. The genetic similarity coefficients were determined with the RAPD data, which ranged from 0.47 to 0.94. The unweighted paired group of arithmetic means (UPGMA) dendrogram presented the studied rice varieties into two major clusters. Moreover, the value of Nei's genetic diversity is 0.26 and the Shanon information index is 0.41. The study produced distinct positions, suggesting that the genotypes were different from each other. The results indicated that these markers could be efficient for comparing the genetic relationships, patterns of variation, and measurement of genetic distance among rice varieties. Considering all of these results, RAPD analysis is found to be an effective tool for estimating the genetic diversity of different rice varieties. The outcomes of this research may contribute to the germplasm data of rice accessions and a future breeding program of rice genotypes.

The Development of Cereal Bars with Dried Anchovy for Chinese Customer Using Check All That Apply (CATA) Analysis for Liking and Disliking

  • Oh, Ji Eun;Yoon, Hei-Ryeo
    • Journal of the Korean Society of Food Culture
    • /
    • v.36 no.3
    • /
    • pp.247-255
    • /
    • 2021
  • Today, energy bars are consumed not only as snacks but also as meal replacement foods. Convenience and nutritional supplementation are the main factors accounting for the increasing use of energy bars. Two hundred Chinese customers who attended the China Fisheries & Seafood Exposition in China, and had no inhibitions about consuming cereal bars were selected. The questionnaire was composed of CATA choices that selected both the reasons for liking and disliking four different types of cereal bars, namely topokki flavor (hot pepper paste), seaweed flavor, kimchi flavor, and ginseng flavor cereal bars with 10% of dried anchovy content produced by BadaOne Co. (Seoul, Korea). The purpose of the study was to investigate Chinese consumer's attitudes and acceptance of different flavored cereal bars containing protein and calciumrich anchovy. For the selected Chinese customers, the acceptance score for the seaweed flavor was the highest, followed by topokki, red ginseng, and kimchi. The acceptance for the topokki flavor was higher than for seaweed for the attributes of color except for general acceptance, flavor, aroma, and texture. The results of the survey showed that the acceptance of kimchi was the lowest, contrary to earlier predictions. The results of the Check All That Apply (CATA) analysis showed that the reasons for liking the seaweed & anchovy flavor were the most diverse, and there was no reason chosen for disliking this flavor. The reasons for liking this flavor were listed as sweet flavor, healthy, seafood flavor, malty flavor, texture, new/unique, and umami. In the case of topokki and kimchi, the reason for disliking the flavor was umami, and in the case of red ginseng, the ginseng flavor was the reason for both likes and dislikes. CA analysis showed that both the flavor and emotional factors were positive for seaweed & anchovy and topokki, but negative for red ginseng. As a result, seaweed & anchovy flavor, which is familiar to the Chinese people, should be the first cereal bar considered for a launch.

Comparison of Morphological Analysis and DNA Metabarcoding of Crustacean Mesozooplankton in the Yellow Sea (황해 갑각 중형동물플랑크톤의 형태 분석과 DNA 메타바코딩 비교)

  • Kim, Garam;Kang, Hyung-Ku;Kim, Choong-Gon;Choi, Jae Ho;Kim, Sung
    • Ocean and Polar Research
    • /
    • v.43 no.1
    • /
    • pp.45-51
    • /
    • 2021
  • Studies on marine zooplankton diversity and ecology are important for understanding marine ecosystem, as well as environmental conservation and fisheries management. DNA metabarcoding is known as a useful tool to reveal and understand diversity among animals, but a comparative evaluation with classical microscopy is still required in order to properly use it for marine zooplankton research. This study compared crustacean mesozooplankton taxa revealed by morphological analysis and metabarcoding of the cytochrome oxidase I (COI). A total of 17 crustacean species were identified by morphological analysis, and 18 species by metabarcoding. Copepods made up the highest proportion of taxa, accounting for more than 50% of the total number of species delineated by both methods. Cladocerans were not found by morphological analysis, whereas amphipods and mysids were not detected by metabarcoding. Unlike morphological analysis, metabarcoding was able to identify decapods down to the species level. There were some discrepancies in copepod species, which could be due to a lack of genetic database, or biases during DNA extraction, amplification, pooling and bioinformatics. Morphological analysis will be useful for ecological studies as it can classify and quantify the life history stages of marine zooplankton that metabarcoding cannot detect. Metabarcoding can be a powerful tool for determining marine zooplankton diversity, if its methods or database are further supplemented.

A Study on the Analysis of Ship Officers' Collision-Avoidance Behavior During Maritime Traffic Simulation (해상교통분석 시뮬레이션을 위한 항해사의 충돌회피 행동분석에 관한 연구)

  • Kim, Hongtae;Ahn, Young-Joong;Yang, Young-Hoon
    • Journal of Navigation and Port Research
    • /
    • v.44 no.6
    • /
    • pp.469-476
    • /
    • 2020
  • Modeling and Simulation (M&S) systems which deal with situational complexity often require human involvement due to the high-level decision-making that is necessary for ship movement, navigation, control center management, shipping company logistics, meteorological system information, and maritime transportation GIS. In order to properly simulate maritime traffic, it is necessary to accurately model the human decision-making process of the ship officer, including aspects of the ship officer's behavioral tendencies, personal navigation experience, and pattern of voyage errors, as this is the most accurate way in which to reproduce and predict realistic maritime traffic conditions. In this paper, which looks at agent-based maritime traffic simulation, we created a basic survey in order to conduct behavior analysis on ship operators' collision avoidance strategies. Using the information gathered throughout the survey, we developed an agent-based navigational behavior model which attempts to capture the behavioral patterns of a ship officer during an instance of ship collision. These results could be used in the future in further developments for more advanced maritime traffic simulation.