• Journal of the Korean earth science society
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• v.30 no.3
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• pp.305-316
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• 2009

Experiments to explain fossilization have been introduced in elementary and middle school science textbooks. Most of them have explained the processes by the mold and cast formed by imprint of bivalve or leaf. The processes explained in the textbooks are more similar to that of trace fossil than body fossil, because the external molds from experiment are imprints after the model was taken off. However fossils of the figures in the textbooks are mostly body fossils. Therefore, the students may be willing to equate the experiment process with the fossilization of the body fossils. The misconceptions were confirmed in this study by the questionnaire which asked 9th grade students on this subject. Many students thought that the body fossils were fossilized imprints and the fossils of terrestrial organism were formed on land without transportation, that is, they did not understand well about biostratinomy and crustal movement. The misconception about the environment in which fossils formed was already reported in a survey on the elementary school students, but has not revised until ninth grade. Therefore, to remove the misconception related to the fossilization, the fossil models in the experiments may be replaced by trace fossils, or new experiments for body fossil should be designed.

• Journal of Wetlands Research
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• v.25 no.4
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• pp.408-416
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• 2023

The IUCN Red List of Ecosystems serves as a global standard for assessing and identifying ecosystems at high risk of biodiversity loss, providing scientific evidence necessary for effective ecosystem management and conservation policy formulation. The IUCN Red List of Ecosystems has been designated as a key indicator (A.1) for Goal A of the Kunming-Montreal Global Biodiversity Framework. The assessment of the Red List of Ecosystems discerns signs of ecosystem collapse through specific criteria: reduction in distribution (Criterion A), restricted distribution (Criterion B), environmental degradation (Criterion C), changes in biological interaction (Criterion D), and quantitative estimation of the risk of ecosystem collapse (Criterion E). Since 2014, the IUCN Red List of Ecosystems has been evaluated in over 110 countries, with more than 80% of the assessments conducted in terrestrial and inland water ecosystems, among which tropical and subtropical forests are distributed ecosystems under threat. The assessment criteria are concentrated on spatial signs (Criteria A and B), accounting for 68.8%. There are three main considerations for applying the Red List of Ecosystems assessment domestically: First, it is necessary to compile applicable terrestrial ecosystem types within the country. Second, it must be determined whether the spatial sign assessment among the Red List of Ecosystems categories can be applied to the various small-scale ecosystems found domestically. Lastly, the collection of usable time series data (50 years) for assessment must be considered. Based on these considerations, applying the IUCN Red List of Ecosystems assessment domestically would enable an accurate understanding of the current state of the country's unique ecosystem types, contributing to global efforts in ecosystem conservation and restoration.

• Journal of Bio-Environment Control
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• v.10 no.3
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• pp.197-206
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• 2001

The depletion of stratospheric ozone is regarded as a major environmental threat to plant growth and ecosystem. The ozone depletion has caused plants to be exposed to an increased penetration of solar ultraviolet-B (UV-B) radiation in the 280-320 nm wavelength range. Enhanced UV-B radiation may have influence on plants biological functions in many aspects including inhibition of photosynthesis, DNA damage, lipid peroxidation, changes in morphology, phenology, and biomass accumulation. To cope with the damage by UV radiation, plants have evolved to have protective mechanisms, such as photorepair, accumulation of UV-absorbing compounds, leaf thickening and activation of antioxidative enzymes. The objective of this review is to address the effects of enhanced UV-B on plant growth, UV-B action mechanisms and protection and protection mechanisms in plants.

• KSBB Journal
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• v.24 no.6
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• pp.495-507
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• 2009

As we move into the 21st century, the importance of marine resources is certain to increase due to the accelerated exhaustion of land resources. For the sustainable development of the world, therefore, we need to develop marine chemical bioindustries which enable us to produce industrial chemicals, advanced materials, fuels, and minerals from marine resources such as seaweeds and seawater. In this review, we selected five marine chemical bioindustries which include 1) seaweed polysaccharide industry, 2) marine advanced materials industry, 3) marine biofuel industry, 4) marine sea salt industry, and 5) deep-sea water industry, and discussed the current status and future prospects of each industry sector. It has been assessed that the future of marine chemical bioindustry looks very promising although there are many needs for more intensive research investments on marine bioprocess development through close cooperation between marine biologists and biochemical engineers.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2003.07a
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• pp.75-75
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• 2003

방향족 화합물인 폴리염화비페닐(PCB)은 비페닐 기본골격의 10개소의 탄소에 1개에서부터 10개까지의 염소가 치환되어 있는 물질로써 그 독성과 잔류성으로 인해 중대한 환경오염물질의 하나로 주목받고 있다. 폴리염화비페닐에 의한 환경오염은 수질오염으로 이어지며, 식물연쇄에 의해 어류의 경우 그 농축계수가 10만 정도까지 이른다고 한다. 이러한 현상은 육상에서도 일어나며 생물농축과 식물연쇄에 의해 결국 식품을 오염시키게 된다. 이와 같은 난분해성 오염물질의 정화에는 미생물이 가지고 있는 분해능력이 큰 역할을 담당한다는 것이 알려져 있다. 1970년대 토양으로부터 비페닐을 분해ㆍ이용할 수 있는 비페닐 자화성균이 단리된 이후, 호기적으로 폴리염화비페닐을 분해하는 균을 중심으로 연구가 행해져 왔으며 방향족 화합물에 있어서의 대사 경로 등이 밝혀지게 되었다. 본 연구에서는 폴리염화비페닐을 분해하는 능력을 가지는 분해균을 모델로 하여 다양한 환경하에서 폴리염화비페닐을 분해ㆍ대사 할 수 있는 미생물의 분리를 시도하였다. 그 결과 클로로비페닐 분해능을 가진 Gram 양성균을 단리하는데 성공하였고, 이 균이 Bacillus속의 미생물인 것을 확인하였다.

• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.3
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• pp.65-73
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• 2011

기후변화는 에너지 수지와 물 수지의 변화를 초래하여 육상 생물권에 영향을 미칠 것이다. 기온과 강수량의 변화와 대기중의 탄산가스 농도 변화는 작물의 생육환경을 크게 변화시킬 것이다. 본 연구에서는 FAO AquaCrop 모형을 이용하여 기온과 강수량의 변화와 대기중 탄산가스 농도의 변화가 짐바브웨의 옥수수 수확량에 미치는 영향을 분석하였다. 미래 기후 값은 HadCM3 모형 예측 값을 change factor 기법으로 상세화 하였다. 배출 시나리오는 A2와 B2를 선정하였으며 시간대는 2020s, 2050s 및 2080s의 30년 기간을 선정하였다. 기준작물 증발산량은 Penman-Monteith 식으로 산정하였다. 관개용수 공급이 충분한 것으로 가정하고 전통적인 보충관개를 실시하였을 때 기준년도 (1970s)에 비해 옥수수 증발산량은 최대 26 %, 옥수수 잠재 수확량은 최대 93 %까지 증가할 것으로 예측되었으며 물의 생산성은 최대 53 %까지 증가할 것으로 예측되었다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.3
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• pp.250-256
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• 2017

This study investigated the removal efficiency of organic matter and nitrogen from fish farm effluent by hydraulic retention time (HRT) using an upflow biological filter (ANR system) reactor. The recycling time and influent flow in the reactor were controlled to 14.8, 7.4, 5.5 and 3.2 h to evaluate HRT. In addition, each reactor was coupled to a fixed bed upflow filter charged with media. The results showed that removal efficiency was ${\geq}95%%$ with an HRT of 5.5 h, and nitrification efficiency was reduced to 81% with an HRT of 3.2 h, although nitrification efficiency temporarily decreased due to the shock load as HRT decreased. Total nitrogen removal rate was also reduced to about 65% with an HRT of 3.2 h, which was considered a washout effect of nitrifying and denitrifying microorganisms by increasing the shearing force to the filter media, which decreased organic matter and nitrogen removal efficiency.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.237-238
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• 2000

전복양식산업은90년대 이후 비약적으로 발전하여 현재는 남해안을 중심으로 전국적으로 넙치양식과 함께 육상수조 및 해상양식에서 큰 비중을 차지하고 있다. 1999년도의 양식현황은 종묘생산 건수가 177건, 수면적 6만7천$m^2$, 연간 생산능력 5천5백만 마리로 나타나고 있으며, 지역별 생산 능력은 남해안 및 제주도가 전국대비 각각 62%, 5.9%, 동해안은 6.3%, 서해안은 25.4%를 차지하고 있다. 이처럼 전복양식 산업의 꾸준한 발달과 규모의 증가 추세로 인하여 전복 종묘에서부터 성패까지 성장 단계별로 선별. 분산기회가 많아지고, 성패의 출하시기에도 많은 양의 박리가 이루어지기 때문에 효율적이고 경제적인 박리방법이 필요하다. 특히, 일시에 대량으로 마취 박리를 할 수 있고, 생물에 대한 상처로 인한 폐사를 줄일 수 있는 안정적이고 효율적인 마취박리 방법이 절실히 요구되고 있다. (중략)

• The Korean Journal of Zoology
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• v.38 no.2
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• pp.160-166
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• 1995

The seven hvpotrichs inhabiting the representative aquatic and terrestrial habitats of Ullung Island, Holosticho svlvotlca, Gonostom urn affine, Histriculus co uicola, H. muscomm, SDlonvchio mytilus, Aspidisca ciccadu and Euplotes m uscicolu are discovered for the first time from Ullung Island. Of these, two species of eonostomum affine (Stein, 1859) and fupfotes muscicofc Kahl, 1932 are newly recorded from Korea. The total seven species are listed and two newly recorded species from Korea are redescribed with illustrations.

• Explosives and Blasting
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• v.28 no.2
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• pp.86-98
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• 2010

As the quality of life is being upgraded, the public complaints about noise and vibration from construction sites are growing. Despite the disputes over the blasting damage on aquatic lives in river, ocean, and aquarium near construction sites tend to increase, most of existing solutions or regulations on the damages caused by blasting are established for the damages on land. Although the estimated amount of damage is up to several millions of USD, there is no guideline for resolving the dispute related to the underwater vibration. This paper presents an example where the public grievance about the underwater noise was successfully resolved by elucidating the characteristics of underwater sound, deducing the correlations between ground vibration and underwater sound during blast, and predicting the underwater sound level during blasting from the ground vibration measured on the ground near an aquarium basin.