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Fish Fauna of the Main Channel in the Nakdong River (낙동강 본류의 어류상)

  • Cho, Ga-Ik;Joo, Gea-Jae;Jang, Min-Ho
    • Korean Journal of Ecology and Environment
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    • v.34 no.3 s.95
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    • pp.223-238
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    • 2001
  • Longitudinal distribution of the fish fauna of the 20 main channel and tributary sites in the Nakdong River was investigated from July 1999 to December 2000. A total of 4,791 individuals of fisHes were collected from three to seven sampling programs of all study sites and 48 species of 17 families were collected. Dominant family was Cyprinidae (25 species, relative abundance (RA): 91.8%). Zacco platypus (RA: 18.0%) was found to be the most abundant inhabitant. Subdominant species were Opsariichthys bidens (17,1%), Squalidus chankaensis tsuchigae (13.2%), Hemibarbus labeo (9.9%), and Z. temmincki (8.2%). Among the total species, 12 species were identified as endemic species (4 families, 24.5% of 1,172 individuals). Four exotic fishes were collected (Carassius cuvieri, 25 indv.; Micropterus salmoides, 214 indv.; Lipomis macrochirus, 14 indv.; Oreochromis niloticus, 6 indv.). M. salmoides was distributed in mid to lower part of the Nakdong River. As the result of cluster analysis, sampling sites were divided into three groups (upper, middle and lowerpart). Site below Gumi (St. 10) were considered as the lower part of the Nakdong River. Combined with previous surveys, about 80 species are present in the main channel and tributaries of the Nakdong River. Since the middle of 1990s, population density of the M. salmoides rapidly increased in the stagnant lower part of the river(RA 8.8% in lower 5 sites). The feeding strategy of M. salmoides was "generalized" on Daphnia sp. (<100 mm), and "specialization" about Cladocera (<150 mm) and Insecta(<200 mm).

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Study of the Status of Naturalized Plants in Busan City, South Korea (부산시 귀화식물의 현황과 고찰)

  • Lee, Chang-Woo;Cho, Hye-Jeong;Kang, Min-Jung;Huh, Man-Kyu;Hwang, In-Chun;Choi, Byoung-Ki
    • Journal of Life Science
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    • v.25 no.11
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    • pp.1244-1254
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    • 2015
  • Naturalized plants were identified and recorded in Busan city based on field surveys and related literature. These plants consisted of 156 taxa in total, belonging to 31 families, 95 genera, 147 species, and 9 varieties. The Compositae had the highest diversity among 31 families, with 44 taxa, followed by Gramineae, with 24 taxa, and Leguminosae, with 10 taxa Among the plants, 68.6% (107 taxa) were annuals and biennials, and 30.1% (47 taxa) were perennials. There was one shrub (Amorpha fruticosa) and one tree (Robinia pseudoacacia). Naturalized degree 5 plants, as common and abundant plant, founded 26 taxa (96.3%) were most highly ratio from Korean naturalized plants. According to the results of the analysis based on place of origin, 50 (32.1%) taxa were from Europe, and 48 (30.8%) taxa were from North America. Epecophyten was the most common of the naturalized plants, with 123 taxa Sixty-six (42.3%) taxa were introduced during period 1, and 15 (9.6%) were introduced during period 4. Ergasiophygophyten (50.6%) and Kenophyten (32.1%) were the dominant plants in these introduction periods. In conclusion, Busan city acts as a conduit for the introduction of naturalized plants. A sustainable management and monitoring strategy may be needed to prevent the introduction and naturalization of plants.

A Study on the Freshwater Fish Community in the Small Streams in Namhae Island, Korea (남해도 소하천 담수어류 군집에 관한 연구)

  • Han, Jeong-Ho;Park, Chan-Seo;Hwang, Hosung;Paek, Woon-Kee
    • Korean Journal of Environment and Ecology
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    • v.30 no.4
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    • pp.730-744
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    • 2016
  • In this study, fish fauna and stream characteristics were surveyed from June to October of 2014 in 31 sites of 23 small streams of Namhae Island. During the study period, 38 species belonging to 30 genera under 13 families were collected. Cyprinidae and Gobiidae fish occupied 28.9% (11 species) and Cobitidae fish accounted for 10.5% (4 species). The dominant family was Cyprinidae, and the most dominant species was Zacco koreanus with 30.3% (1,089 individuals) of the total. Eight species (33.8%) such as Zacco koreanus, Squalidus gracilis majimae, Coreoleuciscus splendidus, Pseudobagrus koreanus, Iksookimia hugowolfeld, Iksookimia longicorpa, Silurus microdorsalis and Liobagrus mediadiposalis were Korean endemic and one species of Micropterus salmoides was exotic. According to the analysis of the community based on the diversity, evenness and richness indices, fish community seems to be more stable in the S7. The small streams were classified into three types of steep mountainous, mountainous-flatland, and flat land streams, and their types were categorized by their features of stream width, water depth, bottom substrate, riparian vegetation, and land use patterns. Principal component analysis based on species abundance classified fish communities into three main groups according to human impact and land-use pattern change. These results suggest that fish community structures were primary affected by the longitudinal environmental changes and these were modified by the habitat condition in accordance with the land use pattern change in the small streams.

A Report on the Occurrence of and Crop Damage Caused by Hyphantria cunea (Drury) with in Korea (국내 미국흰불나방의 최근 발생 및 피해 보고)

  • Kim, Dong-Eon;Kil, Ji-Hyon
    • Korean journal of applied entomology
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    • v.51 no.3
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    • pp.285-293
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    • 2012
  • Occurrence Hyphantria cunea was confirmed in 35 cities and counties nationwide in 2011, each of which reported some form of crop and/or ecological damage caused by the moth. Only a larva of the black-headed form were reported to have occurred in the nation. H. cunea was found in street trees 66.7%, followed by landscape trees 19.4% and forests 13.9%. This suggests that artificial environment 86.1% suffered from H. cunea more severely than natural forests. The study identified 44 families and 102 species of host plants, and found an additional 29 species, to those which had been identified in previous studies. At present, the identified host plants of H. cunea are composed of 62 families and 219 species in total since their first appearance was reported approximately 50 years ago. Host plants include 5 species of food crops (2.3%), 6 species of vegetables (2.7%), 4 species of medicinal crops (1.8%), 1 species of industrial crops (0.5%), 13 species of fruit trees (5.9%), 6 species of other trees crops (2.7%) as well as a further 5 species of farmed crops (2.3%). Seven species of host plants (18.4%) originate from North America where Hyphantria cunea has been introduced from, while 11 species (29.0%) are from China and Japan, Europe and India were the native sources of (10.5%) of the origin with 4 species, respectively. Seventeen species of trees, including Platanus occidentalis L., Ulmus davidiana (var.) japonica (Rehder) (Nakai) and Cornus officinalis (Siebold & Zucc) were heavily noted to be heavily infected with larval populations.

The Impact of Weirs on Fish Assemblage according to Stream Order in Wadeable Stream (Wadeable stream에서 하천차수에 따라 보(weir)가 어류군집에 미치는 영향)

  • Kim, Jeong-Hui;Yoon, Ju-Duk;Park, Sang-Hyeon;Baek, Seung-Ho;Lee, Hae-Jin;Kim, Kyu-Jin;Jang, Min-Ho
    • Korean Journal of Ecology and Environment
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    • v.53 no.2
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    • pp.148-155
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    • 2020
  • In this study, we analyzed the effects of the presence or absence of weirs on fish assemblages in wadeable streams (Stream order 1st~4th). More specifically, we investigated these effects by evaluating the differences in stream size. The results showed differences in the fish assemblages in third or higher order streams (PERMANOVA, P<0.005). The presence or absence of weirs mainly affected variables such as the number of species the individuals, and species richness index, whereas no difference was observed in the populations of exotic, endemic, and endangered species. A SIMPER analysis showed that the common species Zacco platypus, Zacco koreanus, and Pungtungia herzi are dominant in their corresponding streams (contribution>5%), and that these are the main contributors to differences among the fish assemblages. All these species showed high relative abundances at the sites with weirs. Altered environments by the presence of weirs provided these species with concentrated habitats. In summary, this study analyzed the effects of weirs on fish assemblages on a broad, nationwide, scale, and these results can effectively aid future studies on the specific effects of weirs.

Chemical Water Quality and Fish Community Characteristics in the Mid- to Downstream Reach of Geum River (금강 중.하류역의 이.화학적 수질특성 및 어류 군집특성)

  • Han, Jeong-Ho;An, Kwang-Guk
    • Korean Journal of Environmental Biology
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    • v.31 no.3
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    • pp.180-188
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    • 2013
  • The objectives of the study were to analyze chemical water quality and fish community structures in the downstreams of Geum River during 2004~2005. Water quality parameters showed that ionic dilution was evident during July~August due to a rainfall and river runoff by Asian monsoon. Mean concentrations of BOD showed a seasonal variation and were greater in the downstream than in the midstream. The total number of fish species observed was 34 (11 families) and 30.3% of them was Korean endemic species. The dominant species with > 20% of the total were Zacco platypus (25.9%) and Microphysogobio jeoni (21.5%) in the river. Exotic species observed was only one species, Carassius cuvieri with relative abundance of 1.8%. According to the structure analysis of fish community, species richness index was highest (3.714) in S6 and lowest in S4 (1.961), while species diversity index was highest in S2 (1.01) and lowest in S5 (0.507). Tolerant species dominated the fish community (49%), and the sensitive species were rare (4.4%), indicating a biological degradation of ecosystem. In the mean time, omnivore species was composed of 49% in the fish community and insectivore species was nearly same with the proportion of the omnivores.

A Parentage Test using Indel, Microsatellite Markers and Genotypes of MC1R in the Jeju Black Cattle Population (제주 흑우 집단에서 Indel, Microsatellite 마커와 MC1R 유전자형을 이용한 친자 확인)

  • Han, Sang Hyun;Cho, Sang-Rae;Cho, In-Cheol;Cho, Won-Mo;Kim, Sang-Geum;Yang, Sung-Nyun;Kang, Yong-Jun;Park, Yong-Sang;Kim, Young-Hoon;Park, Se-Phil;Kim, Eun-Young;Lee, Sung-Soo;Ko, Moon-Suck
    • Journal of Embryo Transfer
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    • v.28 no.3
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    • pp.207-213
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    • 2013
  • This study was carried out to examine a molecular marker system for parentage test in Jeju Black cattle (JBC). Based on the preliminarily studies, we finally selected for construction of a novel genetic marker system for molecular traceability, identity test, breed certification, and parentage test in JBC and its related industrial populations. The genetic marker system had eight MS markers, five indel markers, and two single nucleotide polymorphisms (SNPs; g.G299T and g.del310G) within MC1R gene which is critical to verify the breed specific genotypes for coat color of JBC differing from those of exotic black cattle breeds such as Holstein and Angus. The results showed lower level of a combined non-exclusion probability for second parent (NE-P2) of $4.1202{\times}10^{-4}$ than those previously recommended by International Society of Animal Genetics (ISAG) of $5.000{\times}10^{-4}$ for parentage, and a combined non-exclusion probability for sib identity (NE-SI) of $2.679{\times}10^{-5}$. Parentage analysis has been successfully identified the JBC offspring in the indigenous population and cattle farms used the certified AI semens for production using the JBC-derived offspring for commercial beef. This combined molecular marker system will be helpful to supply genetic information for parentage test and traceability and to develop the molecular breeding system for improvement of animal productivity in JBC population.

Changes in Weed Vegetation in Paddy Fields over the Last 50 Years in Korea (과거 50년간 우리나라 논잡초 군락의 변화)

  • Lee, In-Yong;Kim, Chang-Seog;Lee, Jeongran;Park, Tae-Seon;Moon, Byeng-Chul;Park, Jae-Eup
    • Weed & Turfgrass Science
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    • v.5 no.1
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    • pp.1-4
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    • 2016
  • The Rural Development Administration of Korea conducted a series of surveys of paddy weeds from 1971 to 2013 in approximately 10-year cycles and the results have been used for the efficient weed management of paddy fields. In 1971, annual weeds such as Rotala indica, Eleocharis acicularis f. longiseta, and Monochoria vaginalis were dominant. In 1981, the population of Echinochloa species decreased whereas broadleaf weeds such as M. vaginalis, Sagittaria pygmaea, and S. trifolia were dominant. In 1991, perennial weeds such as Eleocharis kuroguwai, S. pygmaea, and S. trifolia were dominant over annual weeds. In 2000, M. vaginalis was the most abundant species, followed by E. kuroguwai, Echinochloa species, and S. trifolia. In 2013, herbicide-resistant Echinochloa species and M. vaginalis were most dominant, followed by E. kuroguwai, Scirpus juncoides, and S. trifolia. It has been predicted that the prevalence of Echinochloa species will continue to increase and that perennial weeds will be more abundant than annual ones in the near future. The occurrence of herbicide-resistant weeds and exotic weeds will also increase due to global warming and changes in agricultural patterns.

The Occurrence of Weed Species in Coix lacryma-jobi var. mayuen Fields (율무밭에 발생하는 잡초 양상)

  • Lee, In-Yong;Kim, Chang-Seok;Lee, Jeongran;Han, Jeong-A;Kim, Kyung-Hoon;Kim, Mi-Seon;Song, Hee-Kun;Kim, Duk-Hwan
    • Weed & Turfgrass Science
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    • v.3 no.2
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    • pp.102-109
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    • 2014
  • This study was conducted in order to utilize the basic data for weed control by surveying the occurrence of weed species and the degree of damages caused by those weeds occurred in cultivated Coix lacryma-jobi var. mayuen fields. Survey was carried out three times, from June to September in 2013. The weed flora was composed of a total of 98 weeds, 33 family, of which 58 species were annual, 21 species were biennial, and 19 were perennial plants. Thirty-one exotic species were included as well. Dominance was the highest with Digitaria ciliaris followed by Acalypha australis, Echinochloa crus-galli, Portulaca oleracea, Bidens frondosa etc. in order. In the PCA plot analysis, weeds occurred in C. lacryma-jobi var. mayuen fields were divided into three groups, Panicum dichotomitlorum community, Echinochloa crus-galli-Sigesbeckia pubescens community and Acalypha australis community. Yield of C. lacryma-jobi var. mayuen was reduced 60% in no weeding plots comparing to that in weed management plots.

The Occurrence of Weed species in Cultivated Ligularia fischeri Fields (곰취밭에 발생하는 잡초양상)

  • Lee, In-Yong;Kim, Chang-Seok;Lee, Jeongran;Kim, Jonghwan;Kim, Kyung-Hoon;Kim, Mi-Seon;Song, Hee-Kun;Kim, Duk-Hwan
    • Weed & Turfgrass Science
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    • v.3 no.2
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    • pp.95-101
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    • 2014
  • This study was conducted in order to utilize the basic data for weed control by surveying the occurrence of weed species and the degree of damages caused by those weeds occurred in cultivated Ligularia fischeri fields. Survey was carried out five times, on May, June, July, August and October in 2013. The weed flora was composed of a total of 104 weeds, 37 families, of which 55 species were annual, 25 species were biennial, and 24 were perennial plants. Twenty-six exotic species were included as well. Dominance was the highest with Chenopodium album followed by Stellaria aquatica, Echiochloa crus-galli, Conyza canadensis, and Artemisia princeps etc. in order. In the PCA plot analysis, weeds occurred in cultivated L. fischeri fields were divided into three groups, Persicaria thunbergii-Bidens frondosa community, Chenopodium album community and Capsella bursapastoris community. The degree of damages in cultivated L. fischeri fields was investigated by weighing roots of L. fischeri. We found that 56% decreased root weight in no weeding plots comparing to that in weed management plots. We infer from this result that decreased roots will affect to the growing of L. fischeri in following year.