• 생태와환경
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• 제40권3호
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• pp.449-458
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• 2007

화진포호의 어류군집과 시 공간적 변화를 파악하기 위해 2005년 11월부터 2006년 8월까지 4회에 걸쳐 다양한 조사도구를 사용하여 조사하였다. 채집된 어류는 총 24과 37종 35,812개체였다. 우점종은 H. nipponensis (60.8%), T. hakonensis (19.8%), 그리고 K. punctatus (5.5%) 등 주로 주연성담수어인 것으로 나타났다. 출현한 37종 중 일차담수어와 해산어는 각각 8종(21.6%), 주연성담수어는 21종(56.8%)이었다. 채집된 어종들의 생체량은 총 279.3kg이었으며 T. hakonensis 152.9 kg, H. nipponensis 40.0 kg, K. punctatus 31.4 kg, C. haematochelius 25.3 kg등의 순으로 나타나 내륙의 인공담수호에 비해 생산성이 매우 높은 것으로 나타났다. 조사 시기별 군집의 변화양상은 '갯터짐 현상'에 따라 변화하지만 일부 주연성담수어 개체군은 호내에서 생활사를 가지며 안정된 군집을 이루고 있었다. 이상의 결과로 볼 때, 화진포호는 우리나라에 분포하는 석호 중 비교적 양호한 자연 상태의 생태계를 유지하고 있는 것으로 판단된다 따라서 지속적인 관찰과 모니터링을 통하여 본 석호를 비롯한 다른 석호의 관리와 회복방안을 강구해야 할 것으로 생각된다.

• 한국어류학회지
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• 제28권3호
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• pp.179-185
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• 2016

스텔렛 철갑상어 Acipenser ruthenus의 양식기술 개발 및 분류학적 기초자료를 확보하기 위하여 난 발생 및 자치어 형태 발달을 조사하였다. 친어는 2005년 6월에 PVC 원형수조 (Ø 5 m) 수온 $16.0{\pm}1.0^{\circ}C$에서 성숙시킨 암수 1쌍을 사용하였다. 난은 타원형의 불투명한 침성 점착란으로 크기는 $3.83{\sim}3.85(3.84{\pm}0.01)mm$ (n=10)였다. 난 발생은 건식법으로 인공수정 시켰고, 수정 1시간 후에 배반이 형성, 수정 31시간 후에 낭배말기에 도달하였으며, 수정 82시간 (50%) 후에 부화하였다. 부화 직후 자어는 전장 $10.1{\sim}10.3(10.2{\pm}0.11)mm$ (n=10)로 복부에 큰 난황을 달고 있었다. 부화 17일 후에는 전장 $26.2{\sim}32.4(29.3{\pm}4.39)mm$ (n=10)로 등지느러미 앞쪽이 11개의 굳비늘이 흔적 적으로 발달하기 시작하였다. 부화 50일 후에는 전장 $86.4{\sim}93.1(89.8{\pm}4.71)mm$ (n=10)로 지느러미 기조가 모두 정수에 도달하여 치어기로 이행하였다.

• 한국어류학회지
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• 제10권1호
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• pp.87-97
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• 1998

거제도 지역의 하천을 대상으로 담수어류상과 분포상의 특징을 조사한 결과 총 10과 24종 2,366개체가 채집되었으며, 담수어가 7과 17종, 주연성 어류가 3과 7종이었다. 우점종은 Zacco temmincki로서 428개체(상대풍부도 : 18.1%)가 채집되었으며 아우점종은 Rhinogobius brunneus로 388개체(16.4%)였다. 그 밖의 우세 종으로는 lksookimia longicorpus(290개체, 12.3%), Oryzias latipes( 178개체, 7.5%), Chaenogobius urotaenia(177개체, 7.5%), Carassius auratus(163개체, 6.9%) 등이었으며, 희소종은 Coreoleuciscus splendidus, Silurus microdorsalis, Coreoperca kawamebari 등이었다. 한국 고유종은 C. splendidus, I. longicorpus, S. microdorsalis, Liobagrus mediadiposalis, Liobagrus mediadiposalis ssp.1, Odontobutis platycephala 등 6종으로 전체 어종수의 25.0%를 차지하였다. 군집구조 분석 결과 종다양도는 연초천이 가장 높은 2.21이었으며, 우점도는 외포천과 아주천이 1.00으로 높게 나타났고, 균등도는 외포천이 0.87로 가장 높았다. Aa형의 하천이 대부분인 관계로 상, 중, 하류의 구분없이 중 상류성 어종이 우세하였으며, 서식 어종수는 하천의 유로가 길고 유량이 많을수록 증가하였다. 또한 거제도의 북동부에는 L. mediadiposalis, 서남부에는 L. mediadiposalis ssp.1이 서식하는 분리 분포상을 나타내었으며 이와같은 Liobagrus 속 어류의 분포양상의 중요성을 고지리와 관련하여 논의하였다.

• 생태와환경
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• 제41권4호
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• pp.431-440
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• 2008

Turbid water or suspended sediment is associated with negative effects on aquatic organisms; fish, aquatic invertebrate, and periphyton. Effects of turbid water on fish differ depending on their developmental stage and a level of turbidity. Low turbid water may cause feeding and predation rates, reaction distance, and avoidance in fish, and it could make fish to die under high turbidity and long period. Therefore, it is very important to find out how turbid water or suspended sediment can affect fish in domestic watersheds. The objectives of this study were 1) to introduce international case studies and their standards to deal with suspended sediment, 2) to determine acute toxicity in 4 major freshwater fishes, and 3) to determine in relation to adverse effect of macroinvertebrates and fish. Impacts of turbid water on fish can be categorized into direct and indirect effects, and some factors such as duration and frequency of exposure, toxicity, temperature, life stage of fish, size of particle, time of occurrence, availability of and access to refugia, etc, play important role to decide magnitude of effect. A review of turbidity standard in USA, Canada, and Europe indicated that each standard varied with natural condition, and Alaska allowed liberal increase of turbidity over natural conditions in streams. Even though acute toxicity with four different species did not show any fatal effect, it should be considered to conduct a chronic test (long-term) for more detailed assessment. Compared to the control, dominance index of macroinvertebrates was greater in the turbid site, whereas biotic index, species diversity index, species richness index, and ecological score were smaller in the turbid site. According to histopathological analysis with gills of macroinvertebrate and fishes, morphological and physiological modification of gills due to suspended sediments can cause disturbance of respiration, excretion and secretion. In conclusion, in order to maintain good and healthy aquatic ecosystem, it is the best to minimize or prevent impact by occurrence of turbid water in stream and reservoir. We must make every effort to maintain and manage healthy aquatic ecosystem with additional investigation using various assessment tools and periodic biomonitoring of fish.

• Parasites, Hosts and Diseases
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• 제22권1호
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• pp.127-134
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• 1984

As a series of studies to clarify clonorchicidal substances in body surface mucus of some freshwater fishes, the substance in the epidermal mucus of Cyprinus carpio was isolated by silica gel column and thin layer chromatography and analysed for its chemical nature. Wormicidal trial was done in vitro, and the results obtained are summarized as follows: The mucus was extracted by ethyl ether and separated into 4 fractions by column chromatography using benzene as solvent. The second fraction with yellowish red colour among them showed the strongest clonorchicidal effect. The yellowish red fraction obtained by column chromatography was then fractionated into 6 spots by thin layer chromatography with petrol/ etherjchloroform (30/70, v/v), and the Rf. 0.714 spot among the 6 spots showed the strongest effect. The Rf. 0.714 spot was further fractionated into 6 spots by thin layer chromatography with benzene/acetone (90/10, vlv), and the Rf. 0.800 spot among the later 6 spots revealed the strongest effect. The Rf. 0.800 spot was chromatographed on column with benzene and 2 fractions were obtained. The second fraction of light brown colour represented the final purified fraction. By these Purification Procedures, clonorchicidal substance was Purified 15-fold with 0.035 yield from the mucus of C. carpio, and 10mg of the final fraction killed the cercaria in 26 min, the metacercaria in 115 min, and the adult in 443 min. Infra red and nuclear magnetic resonance spectrometric analysis of the purified substance revealed that the substance belongs to an ethyl ester of unsaturated fatty acid with 2 double bonds, 15 methylene groups and 1 methyl group.

• 한국수산과학회지
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• 제5권4호
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• pp.105-107
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• 1972

붕어(Carassius carassius), 가물치(Ophicephalus argus) 및 미꾸리(Misgurnus anguillicaudatus)의 혈색소상에 미치는 동과 염의 영향을 전분전기영동법으로 연구하였다. 1. 정상 붕어의 혈색소 band는 양극에 1개 있고, band의 수나 이동도가 동이나 염에 의하여 영향을 받지 않았다. 2. 정상 가물치의 혈색소 band는 양극 2개 있고, 이동도는 붕어와 미꾸리의 것보다 빨랐으며 동이나 염의 영향을 받지 않았다. 3 정상 미꾸리의 혈색소 band는 2개로서 양극과 음극에 1개씩 있었고, 기준선으로부터의 상대이동도는 서로 비슷하였다 미꾸리가 동에 처리된 경우 양극에 있는 band의 이동도는 대조군과 염처리군의 이동도보다 상당히 빨랐고, 한편 음극에 있는 혈색소 band는 동과 염의 영향을 받지 않았다. 이 연구를 지도하여 주신 숙명여자대학교 약학대학의 노일협박사님께 깊은 감사를 드린다.

• 환경영향평가
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• 제22권1호
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• pp.27-37
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• 2013

The fish fauna and disturbance of geographical distributions in the eastern Civilian Control Line of Korea were investigated from May to September 2012. Total 35 species sampled during the period were belonged to 13 families. There were 9 Korean endemic species (25.71%) that distributed in the flows into West and South Sea. Distributions of invasion fishes in the studied streams based on geographical distributions of freshwater fish were total 13 species that classified 1 species, C. cuvieri from foreign country and 12 species from other water systems. Hence there have been anthropogenically introduced from too many years ago. Also groups according to the similarities of each studied stations was divided into 4 groups by similarity 50% because difference in them was considered to effect of domestic invasion species. In conclusion, three streams in the eastern Civilian Control Line of Korea were invaded by many alien fishes. Therefore, we are considered to require precise investigation and monitoring for the preparations to management measure.

• Fisheries and Aquatic Sciences
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• 제23권6호
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• pp.15.1-15.14
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• 2020

Background: Large rivers are ecological treasures with high human value, but most have experienced decades of degradation from industrial and municipal sewage, row-crop agricultural practices, and hydrologic alteration. We reviewed published analyses of long-term fish diversity publications from three intensively managed large river ecosystems to demonstrate the conservation potential of large river ecosystems. Results: We show how the incorporation of recent advances in river concepts will allow a better understanding of river ecosystem functioning and conservation. Lastly, we focus on the Wabash River ecosystem based on high conservation value and provide a list of actions to maintain and support the ecosystem. In the Wabash River, there were originally 66 species of freshwater mussels, but now only 30 species with reproducing populations remain. Although there were multiple stressors over the last century, the largest change in Wabash River fish biodiversity was associated with rapid increases in municipal nutrient loading and invasive bigheaded carps. Conclusions: Like similarly neglected large river systems worldwide, the Wabash River has a surprising amount of ecological resilience and recovery. For instance, of the 151 native fish species found in the 1800s, only three species have experienced local extinctions, making the modern assemblage more intact than many comparable rivers in the Mississippi River basin. However, not all the changes are positive or support the idea of recovery. Primary production underpins the productivity of these ecosystems, and the Wabash River phytoplankton assemblages shifted from high-quality green algae in the 1970s to lower less nutritional blue-green algae as nutrient and invasive species have recently increased. Our recommendations for the Wabash River and other altered rivers include the restoration of natural hydrology for the mainstem and tributaries, nutrient reductions, mechanisms to restore historical hydrologic patterns, additional sediment controls, and improved local hydraulics.

• Ocean and Polar Research
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• 제26권3호
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• pp.433-438
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• 2004

Stress response to the seawater acclimation in coho salmon (Oncorhynchus kisutch) smolt was investigated. Salt concentration of rearing water was gradually increased for 3 days from freshwater to seawater (30 ppt salt level). The changes of serum concentrations of cortisol as a primary stress indicator, and as secondary indicators, glucose (GLC), lactate (LAC), triglyce.ide (TG), cholesterol (CHOL), sodium ion $(Na^+)$, chloride ion $(Cl^-)$ and enzyme activities (alanine aminotransferase, ALT: aspartate aminotrasferase, AST; lactate dehydrogenase, LDH) were quantified during the acclimation experiment. Among them, cortisol, LAC, TG, CHOL, ALT, AST concentrations showed rapid increase at the first exposure to the 10ppt salt level (day 1), and began to decrease to the constant values after day 2 of adaptation at 20ppt salt level. However, LDH concentration tended to decrease during the whole experimental period. $Na^+\;and\;Cl^-$ showed slight decrease at day 1, and increased to a little bit higher values after day 2 rather than those in freshwater. All the fishes started on taking a food after day 4 of seawater adaptation. From these results, to reduce osmotic shock inducible stress to fish in seawater acclimation, gradual increase of salt levels is recommended.

• Parasites, Hosts and Diseases
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• 제35권4호
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• pp.223-232
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• 1997

Metagonimus miyatai n. sp. (Digenea: Heterophyidae) is described based on adult flukes collected from experimental dogs and hamsters fed with metacercariae encysted in the sweetfish, Plecoglossus altivelis, dace, Tribolodon hakonensis and T. taczanowskii, common fat-minnow. Morocco steindachneri pale chub, Zacco platypus, and dark chub, Zacco temmincki, and on those collected from naturally infected humans. The new species was morphologically compared with M. yokogawai and M. takahashii obtained from experimental animals fed with the sweetflsh and the crucian carp, Cnrossius caressius, respectively. The uterine loops of M. miyatai reached near the posterior end of the body through the space between the two testes, whereas those of M. yokogawai, occupied only the space between the acetabulum and anterior border of two testes. This uterine tubule distribution was similar to that of another closely related species, M. takahashii. However vitellaria of M. miyatai ended in front of the posterior end of the left testis, while those of M. takahcshii reached the posterior end of the left testis and ran it over. By raising M. miyatai as a new species, differentiation of M. yokogawai and M. takahashii became very clear. A key to the species of the genus Metagonimus in the Far East has been proposed.