• Title/Summary/Keyword: exotic species

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Ecological Characteristics and Long-term Variation of Fish Community in Lake Paldang and its Tributaries (팔당호 어류군집의 생태특성 및 장기 변동)

  • Park, Hae-Kyung;Lee, Jangho;Choi, Myung-Jae;Yun, Seuk-Hwan;Song, Ho-Bok;Lee, Kyoo;Youn, Seok Jea;Shin, Kyungae;Byeon, Myeong-Seop;Kong, Dongsoo
    • Journal of Korean Society on Water Environment
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    • v.25 no.6
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    • pp.951-963
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    • 2009
  • The community structure and ecological characteristics of fish community in Lake Paldang were investigated from May to September 2008. During the survey period, 53 species belonging to 13 families were collected. Dominant species was Squalidus japonicus coreanus representing 81.8% of total number and 25.7% of total biomass of collected fish and subdominant species was Lepomis macrochirus representing 3.3% of total number and 18.9% of total biomass of collected fish. There were 20 Korean endemic species (38% of collected species number) including Cottus koreanus and 4 exotic species (7.5%) including Micropterus salmoides. The similarity analysis of fish communities among water areas of Lake Paldang using UPGMA showed that fish community of North-Han River was similar to that of South-Han River area and was different from that of Gyeongan River area. Long-term variation of fish community from 1972 to present study in Lake Paldang showed decrease of the species numbers after dam construction until 1994, and gradual increase from 1996 to present study indicating the disturbance of lentic system by dam construction in the 1980s. The increase of species number in the late 2000s may results in part from the increase of survey sites of successive studies. L. macrochirus which was designated as a domestic ecosystem-disturbing alien species with wide food niche have shown more than 20% of relative abundance since 1996 indicating the adverse effect on not only fish community but also aquatic ecosystem food web of Lake Paldang.

Prediction of Shift in Fish Distributions in the Geum River Watershed under Climate Change (기후변화에 따른 금강 유역의 어류 종분포 변화 예측)

  • Bae, Eunhye;Jung, Jinho
    • Ecology and Resilient Infrastructure
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    • v.2 no.3
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    • pp.198-205
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    • 2015
  • Impacts of climate change on aquatic ecosystems range from changes in physiological processes of aquatic organisms to species distribution. In this study, MaxEnt that has high prediction power without nonoccurrence data was used to simulate fish distribution changes in the Geum river watershed according to climate change. The fish distribution in 2050 and 2100 was predicted with RCP 8.5 climate change scenario using fish occurrence data (a total of 47 species, including 17 endemic species) from 2007 to 2009 at 134 survey points and 9 environmental variables (monthly lowest, highest and average air temperature, monthly precipitation, monthly lowest, highest and average water temperature, altitude and slope). The fitness of MaxEnt modeling was successful with the area under the relative operating characteristic curve (AUC) of 0.798, and environmental variables that showed a high level of prediction were as follows: altitude, monthly average precipitation and monthly lowest water temperature. As climate change proceeds until 2100, the probability of occurrence for Odontobutis interrupta and Acheilognathus yamatsuatea (endemic species) decreases whereas the probability of occurrence for Microphysogobio yaluensis and Lepomis macrochirus (exotic species) increases. In particular, five fish species (Gnathopogon strigatus, Misgurnus mizolepis, Erythroculter erythropterus, A. yamatsuatea and A. koreensis) were expected to become extinct in the Geum river watershed in 2100. In addition, the species rich area was expected to move to the northern part of the Geum river watershed. These findings suggest that water temperature increase caused by climate change may disturb the aquatic ecosystem of Geum river watershed significantly.

Spreading and Distribution of Exotic Weed Ammannia coccinea in Korea (외래잡초 미국좀부처꽃(Ammannia coccinea)의 확산과 생육지 특성)

  • Hwang, Sunmin;Kil, Jihyon;Kim, Youngha;Kim, Seungryul
    • Weed & Turfgrass Science
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    • v.3 no.4
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    • pp.292-298
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    • 2014
  • Purple ammannia (Ammannia coccinea Rottb.) is an exotic weed originated from North America. It was known to be a noxious weed in a rice paddy field for the competition with rice. We investigated its distribution and habitat types in Korea to obtain basic data for the management plan of this species. Although purple ammannia is currently not a dominant species in natural habitats, its nationwide distribution was found in our study. We categorized the types of its habitats as margins of rice paddies, abandoned paddy fields, riverine wetlands and reservoirs. Particularly, purple ammannia plants were frequently located along banks of irrigation channels that ran through rice paddies and surrounding wetlands. Because they mainly occurred along the direction of water flow, we considered that the plants have spread along water courses. A total of 69 vascular plant taxa was identified at the habitats of purple ammannia. The largest group of life form among purple ammannia population was therophytes, which indicates that purple ammannia mostly grow in the disturbed habitats.

Study on the diagnosis of disturbed forest ecosystem in the Republic of Korea: in case of Daegwallyeong and Chupungryeong

  • Lee, Seon-Mi;Cha, Jae-Gyu;Moon, Ho-Gyung
    • Journal of Ecology and Environment
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    • v.41 no.7
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    • pp.182-190
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    • 2017
  • Background: Baekdudaegan was designated in 2005 as a protected area to prevent destruction and conserve. However, there are many disturbed and destroyed areas. The total disturbed area amounts to $25.9km^2$ (0.94%), including $13.4km^2$ (0.49%) in the core area and $12.5km^2$ (0.45%) in the buffer area. This study aims to classify the vegetation types established in the disturbed areas and diagnose the current conditions for ecological restoration in the forest ecosystem. Methods: We surveyed the vegetation in the disturbed areas of Daegwallyeong and Chupungryeong and the surrounding natural areas. The survey conducted from July to September 2015 targeted a total of 54 quadrats by Braun-Blanquet method (Daegwallyeong, 22; Chupungryeong, 32). We also investigated the height and coverage of each layer. We classified the vegetation types based on the field data and analyzed the ratio of life form and the exotic plants, species richness, and vegetation index (Hcl). The Normalized Difference Vegetation Index (NDVI) was calculated from rapideye satellite imagery in 2014 and 2015. Results: Vegetation types were classified into 11 groups according to the criteria that included successional sere or plantation at first, followed by developmental stage and origins. As a result of the analysis of the survey data, species richness, vegetation index (Hcl), ratio of tree plants, and the NDVI tended to increase, while the ratio of the exotic plants tended to decrease with the time since disturbance. These indicators had the classified values according to the vegetation types with time since the disturbance. Conclusions: These indicators can be effectively used to diagnose the conditions of the present vegetation in the disturbed area of the Baekdudaegan area. In addition, the NDVI might be effective for the diagnosis of the disturbed status instead of the human efforts based on the higher spatial resolution of satellite imagery. Appropriate diagnosis of the disturbed forests in the Baekdudaegan area considering the established vegetation types is essential for the elaboration of restoration plans. In addition, restoration target and level should be different according to the disturbed status of restoration site.

COI-Based Genetic Structure of an Exotic Snapping Turtle Chelydra serpentina Imported to South Korea

  • Baek, Su Youn;Shin, ChoRong;Kim, Kyung Min;Choi, Eun-Hwa;Hwang, Jihye;Jun, Jumin;Park, Taeseo;Kil, Hyun Jong;Suk, Ho Young;Min, Mi-Sook;Park, Yoonseong;Lee, YoungSup;Hwang, Ui Wook
    • Animal Systematics, Evolution and Diversity
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    • v.36 no.4
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    • pp.354-362
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    • 2020
  • A common snapping turtle Chelydra serpentina inhabiting North America is internationally protected as an endangered species. It is known that the individuals of common snapping turtles were imported to South Korea as pets, and after being abandoned, some inhabit the natural ecosystem of South Korea like wild animals. No genetic survey has yet been performed for the common snapping turtles imported to South Korea. Hereby, cytochrome c oxidase subunit I (COI) information, which is 594 bp long, was determined for a total of 16 C. serpentina individuals, of which one was found in nature, twelve legally imported and their descendants, and the other three were provided from the Kansas Herpetological Society, USA. The obtained data were combined with thirteen COI sequences of C. serpentina retrieved from NCBI GenBank for the subsequent population genetic analyses. The results showed that there exist five haplotypes with high sequence similarity (only three parsimoniously informative sites). In the TCS and phylogenetic analyses, all the examined C. serpentina samples coincidently formed a strong monoclade with those collected mostly from Kansas State, USA, indicating that the imported ones to South Korea are from the central North America. In addition, there found the amino acid changes and the high degree of nucleotide sequence differences between C. serpentina and C. rossignoni with some important morphological characters. It is expected that the present results could provide an important framework for systematic management and control of exotic snapping turtles imported and released to nature of South Korea.

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.

Ichthyofauna and Structure of the Fish Community in Lake Goesan, Korea (괴산호 어류상 및 군집구조)

  • Hong, Yang-Ki;Kim, Kyeong-Hwan;Song, Mi-Young;Lee, Wan-Ok
    • Korean Journal of Environment and Ecology
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    • v.29 no.4
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    • pp.552-563
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    • 2015
  • The characteristics of ichthyofauna and fish community in Lake Goesan were examined from April 2010 to October 2012. During the survey period thirty six species belonging to 11 families were collected. Dominant species by number were Hemibarbus labeo (29.9%) and Zacco platypus (20.0%). In biomass, the dominant species were H. labeo (37.2%) and Carassius auratus (17.9%). Also, fourteen Korean endemic fish species (38.9%) and one endangered species (Acheilognathus signifer) were collected. Further, one catadromous species was observed for stock enhancement (Anguilla japonica), in addition to two land-locked anadromous species (Hypomesus nipponensis, Plecoglossus altivelis) and three exotic species (Cyprinus carpio (Israeli type), C. cuvieri, Micropterus salmoides). According to the length-weight relation of C. auratus and M. salmoides, the b values were 3.13~2.99, 3.11~2.99, showing a declining tendency annually. However, for H. labeo and Z. platypus, the b values were 2.98~3.07, 3.06~3.23 respectively, showing an increasing trend. The slope values for C. auratus and M. salmoides population conditions were controlled by K factor showing a tendency to decrease, but H. labeo and Z. platypus were showing a tendency to gradually increase.

Characteristics of Fish Fauna and Community Structure in Daecheon Stream in Boryeong, Korea (보령 대천천의 어류상과 어류 군집 특성)

  • Song, Mi-Young;Jung, Seung-Yoon;Kim, Kyung-Hwan;Baek, Jae-Min;Lee, Wan-Ok
    • Korean Journal of Environment and Ecology
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    • v.27 no.4
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    • pp.437-448
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    • 2013
  • The ichthyofauna and fish community were studied in Daecheon Stream from April to October 2012. During the survey period a total of 42 species belonging to 13 families were collected. Dominant species by number was Zacco platypus(32.3%) and Tridentiger brevispinis(12.8%). In biomass, the dominant species was Z. platypus(27.7%) and Chelon haematocheilus(11.9%). Also, eight Korean endemic fish species and one endangered species (Rhodeus pseudosericeus) were collected. In addition, two exotic species(Carassius cuvieri and Micropterus salmoides) and migration fish species(Anguila japonica) were observed. Based on the length-weight relationship of Z. platypus, the b value was 3.21~3.29, and the condition factor(K) was 0.89 on average with stable condition. According to similarity analysis, fish communities in Daecheon Stream were divided into three groups; the upper reaches near a reservoir(St. 1), the middle reaches (St. 2 to 4) and the lower reaches near a weir(St. 5). Dominant species at each group were Zacco koreanus(St. 1), Z. platypus(St. 2 to 4) and T. brevispinis(St. 5). This result suggested that artificial structures such as dam and a weir have a marked effect on the distribution of fish communities in Daecheon Stream.

Community Structure of Fish and Distribution Characteristics of Phoxinus phoxinus and Rhynchocypris kumgangensis in the Gihwacheon Stream of Namhangang River, Korea (남한강 지류 기화천의 어류 군집 구조 및 연준모치와 금강모치의 분포 특성)

  • Jeon, Hyoung-Joo;Baek, Jeong-Ik;Kim, Kyung-Hwan;Kim, Seung-Yong;Lee, Wan-Ok;Kwak, Ihn-Sil;Song, Mi-Young
    • Korean Journal of Ichthyology
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    • v.31 no.2
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    • pp.90-100
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    • 2019
  • This study was carried out from March to November, 2013 to investigate the fish community structure and distribution characteristics of Phoxinus phoxinus and Rhynchocypris kumgangensis appearing in Gihwacheon Stream, Pyeongchang. A total of 6 families and 19 species of fish emerged during the survey period. The dominant species were R. kumgangensis (Individuals 44.7%, Biomass 30.2%) and P. phoxinus (Individuals 27.7%, Biomass 15.9%). Endemic species were 10 species including Pseudopungtungia tenuicorpus, Coreoleuciscus splendidus, Hemibarbus mylodon, Gobiobotia brevibarba, Microphysogobio longidorsalis, R. kumgangensis, Zacco koreanus, Korecobitis rotundicaudata, Iksookimis koreensis and Coreoperca herzi. Endogenous species were P. tenuicorpus, G. brevibarba and P. phoxinus. Hemibarbus mylodon was a natural monument. Oncherhynchus mykiss was exotic species and translocated species was Oncorhynchus masou masou. The dominant species, R. kumgangensis, appeared at all survey sites. Except for St.6, the b value was more than 3.0 and the slope of K value showed positive correlation. P. phoxinus appeared in St. 3~St. 6 and St. 3 and St. 4 only showed stable populations.

Characteristics of Fish Communities and Length-weight Relationships of Dominant Species (Zacco platypus) in Seomjin River (섬진강 수계 어류군집 특성과 우점종 피라미(Zacco platypus)의 전장 - 체중 관계 분석)

  • Lee, Sun Ho;Kim, Hyo Gyeom;Jo, Hyunbin;Kwak, Ihn-Sil
    • Korean Journal of Ecology and Environment
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    • v.54 no.1
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    • pp.12-23
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    • 2021
  • As fish communities are sensitive to natural environmental changes as well as anthropogenic pressures, their composition and characteristics help us to assess the aquatic ecosystem health. The fish fauna and the length-weight relationship of Zacco platypus in the Seomjin River system were investigated from July 2018 to May 2019. The collected species during the survey period were 49 species belong to 14 families including 19 Korean endemic and two endangered species. According to Bray-Curtis similarities, 14 sites were divided into four groups based on the fish community composition; two groups(group A, B) and two uncategorized sites(group C, D). There were significant differences between groups A and B(analysis of similarities, R=0.722, p=0.002). A similarity percentage analysis revealed that Z. koreanus(8.55%), Micropterus salmoides(6.90%), and Lepomis macrochirus (4.90%) contributed to these differences of fish assemblages between group A and B. Group A showed higher relative abundances of exotic species such as M. salmoides and L. macrochirus, while Z. platypus and Z. koreanus which are the common species in Korea, were the most dominant species in group B. Based on the length-weight relationship of Z. platypus, b values were varied from 2.82 to 3.80, indicating that growth patterns of the species were spatially different. This study could be served as baseline data for understanding fish fauna, assessing habitat characteristics based on the fauna, and identifying health conditions of Z. platypus in the Seomjin River system.