• Title/Summary/Keyword: 열목어

Search Result 29, Processing Time 0.027 seconds

The Characteristic of Fish Fauna and Brachimystax lenok tsinlingensis Individuals in the Bonghwa-gun, Korea (봉화군의 어류상과 열목어(Brachimystax lenok tsinlingensis) 개체군의 특성)

  • Byeon, Hwa-Kun
    • Korean Journal of Environment and Ecology
    • /
    • v.25 no.6
    • /
    • pp.878-886
    • /
    • 2011
  • The fish fauna and characteristic of population of Brachymystax lenok tsinlingensis at the 7 stations in the Bonghwa-gun were investigated from June 2010 to May 2011. The collected species during the survey period were 15 species belong to 7 families. Protected species by the legal were B. lenok tsinlingensis, Koreocobitis naktongensis, and Cottus koreanus. Korean endemic species were Microphy sogobio yaluensis, Coreoleuciscus splendidus, Zacco koreanus, Cobitis hankugensis, K. naktongensis, Iksookimia longicorpa, Niwaella multifasciata, Liobagrus mediadiposalis, C. koreanus, and Coreoperca herzi, which showed a ration of 66.7% in collected species. Dominant species were Z. koreanus(St. 1), B. lenok tsinlingensis(St. 3, 4, 5), and Rhynchocypris oxycephalus(St. 2, 6, 7). Length-weight relation in the population of B. lenok tsinlingensis was BW = $0.000008TL^{3.02}$, and condition factor in the population was average 0.84. Frequency analysis of total length indicated that the group 80~180 mm in total length is represented by one-year-old individuals, the group 200~300 mm by two-year-old individuals, and the group over 300 mm by three-year-old individuals. The density of population was presumed average 17 individuals per 100$m^2$ and total 4,760 individuals in the reservation for B. lenok tsinlingensis.

Evaluation on Watershed Natural Habitat Assessment for Conservation of Brachymystax lenok tsinlingensis in Naerin Upstream (내린천 상류 유역 열목어(Brachymystax lenok tslingensis) 서식지 자연성 평가)

  • Jeong Eun Kim;Hwang Goo Lee
    • Ecology and Resilient Infrastructure
    • /
    • v.10 no.3
    • /
    • pp.73-84
    • /
    • 2023
  • The objective of this study was to evaluate biodiversity and natural habitat environment of freshwater ecosystem. Our aim was therefore to produce a set of biodiversity and habitat indicators based on multi-parameters of water quality and biodiversity by analyzing the characteristics of the results by indicators. We selected four indicators a) anthropogenic disturbance, b) habitat diversity, c) biodiversity, d) ecosystem structure. The fishes cohabiting with Brachymystax lenok tsinlingensis were Rhynchocypris kumgangensis and Zacco koreanus. As a result of the anthropogenic disturbance evaluation, it was analyzed that vegetation embankment showed a more stable environment in the tributary than the main stream, and other disturbance was not confirmed As a result of the habitat diversity evaluation, it was analyzed that habitat evaluation index showed a high score of 200 more on average, showing an optimal habitat condition. As a result of the biodiversity evaluation, it was analyzed as a clean habitat condition with a high proportion of sensitive species, abundant dissolved oxygen, and little pollutants. As a results of the ecosystem structure, the ecological health condition metrics and appearance of endangered species showed large score deviation, but it was analyzed that the stream ecosystem health was generally excellent. There was a slight correlation between the habitat environment and the results of the nature habitat evaluation according to the appearance of the B. lenok tsinlingensis.

Distribution Status, Habitat Characteristics and Extinction Threat Evaluation of the Endangered Species, Brachymystax lenok tsinlingensis (Pisces: Salmonidae) (멸종위기어류 열목어 Brachymystax lenok tsinlingensis (Pisces: Salmonidae)의 분포현황과 서식지 특징, 멸종위협 평가)

  • Ko, Myeong-Hun;Choi, Kwang-Seek;Han, Mee-Sook
    • Korean Journal of Ichthyology
    • /
    • v.33 no.2
    • /
    • pp.74-83
    • /
    • 2021
  • Distribution status, habitat characteristics, and extinction threat evaluation of the endangered species, Brachymystax lenok tsinlingensis were investigated in 2015 and 2019. Historical distribution reports of B. l. tsinlingensis were divided into before 1990, 1997~2006, 2000~2011, and 2010~2019. Among the 150 sampling sites investigated during the study period, number of individuals of B. l. tsinlingensis were collected 542 individuals from 67 sites. The streams inhabited of B. l. tsinlingensis were Naerincheon (11 stations), Odaecheon (11 stations), Bukcheon (10 stations), Bangtaecheon (8 stations), Songjeongricheon (4 stations), Suipcheon (3 stations), Inbukcheon (3 stations), Hyeondongcheon (3 stations) etc. The main habitat of B. l. tsinlingensis was upstream of the river with a high altitude of more than 400 m, 4~20 m water flow width, 1~2 m water depth, and high ratio (70~80%) boulder bottoms. The main reasons for the decline in population size were assumed as river works, construction of reservoirs and bridges, discharge of contaminated water into the river, the inflow of summer vacationers, and weir. Compared to our results there exists evidence that states a 20.7% reduction in occupancy within 10 years, in a small appearance range (7,732 km2) and occupancy area (268 km2), number of disconnected locations (15 locations), and a decline in habitat quality. Therefore, B. l. tsinlingensis is now considered as Near Threatened (NT) based on the results (Near meets VU A2acd, B1b(i,ii,iii)+B2b(i,ii,iii)) of IUCN Red List categories and criteria.

Maturation Induction by Manchurian Trout Recombinant Gonadotropin Hormone (mt-rGTH) in Female Eel, Anguilla japonica (열목어 재조합 생식선자극호르몬(mt-rGTH)에 의한 암컷 뱀장어의 성성숙 유도)

  • Kim, Dae-Jung;Park, Woodong;Sohn, Young Chang;Bae, Jun-Young;Yoon, Seong Jong;Son, Maeng Hyun;Kobayashi, Makito;Han, Chang-Hee
    • Development and Reproduction
    • /
    • v.12 no.3
    • /
    • pp.261-266
    • /
    • 2008
  • In the present study, we investigated in vivo effects of Manchurian trout recombinant gonadotrophin hormone (mt-rGTH) on the induction of maturation in female eel, Anguilla japonica. The brood stock, female eel (450$\pm$50 g) were weekly injected intramuscularly with different doses of 0.1, 1, 10 ${\mu}g\m{\ell}$/fish (mt-rFSH or mt-rLH) for 10 week. The effects of r-mtGTH were analyzed by gonadosomatic index (GSI), ovarian follicle diameter and sex steroid levels. All groups did not exhibit significant differences in the GSI values. Whereas plasma testosterone (T) and estradiol-17$\beta$ (E2) levels did not change significantly in control group, plasma levels of T and E2 by injection of the r-mtFSH or r-mtLH were increased at 2 or 4 week after injection. In addition, injection of the mt-rFSH (1, 10 ${\mu}g/m{\ell}$/fish) or mt-rLH (0.1, 1, 10 ${\mu}g/m{\ell}$/fish) significantly increased follicle diameters comparing to the control group. These results demonstrate that the recombinant hormone may affect early ovary development and maturation in female eel. Taken together, these results suggest that the recombinant Manchurian trout FSH and LH are effective for reproductive activities in female eel.

  • PDF

저 깊은 계곡, 차고 깨끗한 물 속에 열목어와 산천어가 있다!

  • Song, Ho-Bok
    • 한국상하수도협회지
    • /
    • s.3
    • /
    • pp.84-85
    • /
    • 2003
  • 일반인들은 BOD나 COD가 몇 ppm 쯤 되어야 1급수인지, 또는 DO의 농도는 얼마나 되어야 2급수가 되는지 알고 있을까? 그 숫자들을 기억하는 사람들은 별로 없을 것이다. 그러나 집 앞에 흐르는 냇물이 1급수인지, 2급수인지 쉽게 판별하는 아주 좋은 방법이 있다. 바로 지표생물을 통해서이다. 어떤 환경에 서식하면서 그 환경의 상태를 나타내는 생물들을 지표생물이라 하는데, 수환경도 마찬가지로 금강모치나 플라나리아가 살면 1급수, 피라미는 2급수, 붕어나 잉어가 살면 3급수, 실지렁이가 살면 4-5급수 등으로 구분할 수 있다.

  • PDF

Comparison of Carotenoid Pigments on Manchurian Trout, Brachymystax lenok and Masu Salmon, Oncorhynchus macrostomus in the Family Salmonidae (연어과에 속하는 열목어와 산천어의 Carotenoid 색소성분의 비교)

  • BAEK Sung-Han;HA Bong-Seuk
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.31 no.2
    • /
    • pp.278-287
    • /
    • 1998
  • Carotenoids in integument of wild manchurian trout, Brachymystax lenok, and wild and cultured masu salmon Oncohynchus macrostomus, which are all the Korean native cold fresh water fish, were investigated by thin layer chromatography, column chromatography and HPLC. The total carotenoid contents of the wild manchurian trout were $3.72\;mg\%$ which is relatively higher compare to other species of salmonidae. The carotenoids were composed of $36.9\%$ zeaxanthin and $14.7\%$ $\beta-carotene$ as the major compounds, $7.8\%$ triol $7.3\%$ isocryptoxanthin, $5.7\%$ 4-hydroxy echinenone, $4.7\%$ lutein, $4.5\%$ salmoxanthin and $2.2\%$ astaxanthin as minor compounds, and other carotenoids such as canthaxanthin, tunaxanthin A, tunaxanthin B, tunaxanthin C, $\beta-cryptoxanthin$ and $\alpha-cryptoxanthin$ as minute carotenoids. Wild masu salmon contained more total carotenoids than cultured one and the contents were $0.82\;mg\%$ and $0.66\;mg\%$, respectively. The composition of the carotenoids from wild masu salmon were $20.7\%$ xeaxanthin, $17.0\%$ isocryptoxanthin and $15.8\%\;\beta-carotene$ as major compounds, and $6.2\%$ triol, $6.1\%$ 4-hydroxy echinenone, $6.1\%$ salmoxanthin, $5.9\%$ canthaxanthin, $5.8\%$ lutein, $4.9\%$ $\alpha-cryptoxanthin$ and $1.0\%$ astaxanthin as minor compounds. The composition of the carotenoids from cultured masu salmon were $19.7\%$ isocryptoxanthin, $18.0\%$ $\beta-carotene$ and $10.3\%$ zeaxanthin as the major compounds, and $8.9\%\;\beta-cryptoxanthin$, $8.5\%\;\alpha-cryptoxanthin$, $8.0\%$ lutein, $7.6\%$ canthaxanthin, $5.1\%$ triol and $2.0\%$ astaxanthin as minor carotenoids. Based on these data, wild masu salmon contained more zeaxanthin, salmoxanthin and 4-hydroxy echinenone while cultured masu salmon contained more $\alpha-cryptoxanthin$, indicating that carotenoid pigment of masu salmon depends on their living conditions. Unlike wild masu salmon, 4-hydroxy echinenone and salmoxanthin which are the characteristic carotenoids of salmons, were not found in the integument of cultured masu salmon. Unlike manchurian trout, both wild and cultured masu salmon did not contain tunaxanthin A, tunaxanthin B and tunaxanthin C.

  • PDF

Fish Community Characteristics and Inhabiting Status of Endangered Species in the Bukcheon (Stream) of Seoraksan National Park, Korea (설악산국립공원 내 북천의 어류군집 특성 및 멸종위기종의 서식양상)

  • Park, Seong-Cheol;Choi, Kwang-Seek;Han, Mee-Sook;Ko, Myeong-Hun
    • Korean Journal of Environment and Ecology
    • /
    • v.36 no.4
    • /
    • pp.390-401
    • /
    • 2022
  • This study investigated the characteristics of fish communities and inhabiting status of endangered species in the Bukcheon (Stream) of Seoraksan National Park, Korea from April to September 2020. A total of 4,356 fish of 7 families and 22 species were collected from 17 survey stations during the survey period. The dominant species was Zacco koreanus (relative abundance, 41.8%), and subdominant species was Rhynchocypris kumgangensis (relative abundance, 15.1%), followed by Pungtungia herzi (10.1%), Pseudopungtungia tenuicorpa (5.0%), Coreoleuciscus splendidus (4.1%), Zacco platypus (3.8%), Microphysogobio longidorsalis (3.5%), and Hemibarbus mylodon (2.2%). Among the fish species collected, 14 species (63.6%) were identified as Korean endemic species. There was one natural monument species (Hemibarbus mylodon), and four species of class II endangered wildlife that were designated by the Ministry of Environment (Acheilognathus signifer, Pseudopungtungi tenuicorpa, Gobiobotia brevibarba, and Brachymystax lenok tsinlingensis). Among the four species of class II endangered wildlife, B. lenok tsinlingensis inhabited in the upper stream, and A. signifer, P. tenuicorpa and G. brevibarba inhabited mainly in the middle-lower stream. Also, P. tenuicorpa, H. mylodon, and B. lenok tsinlingensis were inhabited in large numbers. Additionally, two cold-water fish species (R. kumgangensis and B. lenok tsinlingensis) and one landlocked species (B. lenok tsinlingensis) were collected. According to the results of cluster analysis, the dominance index decreased from upstream to downstream, but the diversity, evenness, and richness index increased; the cluster structure was divided into the uppermost, upstream, midstream, and downstream. The water quality of Bukcheon was evaluated as good overall since the river health (index of biological integrity) evaluated using fish was evaluated as very good (11 stations), good (2 stations), and normal (4 stations). However, river repair work was being carried out in some areas and some wastewater was flowing in from the midstream, therefore, supplementary measures to preserve fish habitats are required.