• 제목/요약/키워드: freshwater environment

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Six Newly Recorded Fungal Taxa from Freshwater Niche in Korea

  • Lim, Hyo Jin;Nguyen, Thuong T.T;Lee, Hyang Burm
    • Mycobiology
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    • 제49권2호
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    • pp.105-121
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    • 2021
  • Six interesting fungal strains were isolated during a survey of fungal diversity associated with freshwater; these strains were designated as CNUFC YJW2-22, CNUFC MSW11-6-2, CNUFC HRS5-3, CNUFC MSW242-6, CNUFC DMW2-2, and CNUFC CPWS-1. Based on a polyphasic approach including phylogenetic analyses of internal transcribed space (ITS), large subunit (LSU), beta-tubulin (BenA), and calmodulin (CaM) gene sequences, morphological analyses, the six strains were found to be identical to Acremonium guillematii, Cadophora novi-eboraci, Lectera nordwiniana, Mycoarthris corallina, Talaromyces siamensis, and Tetracladium globosum, respectively. To our knowledge, these are the first records of the rare Lectera, Mycoarthris, and Tetracladium genera in Korea, and the first reports of A. guillematii, C. novi-eboraci, L. nordwiniana, M. corallina, T. siamensis, and Te. globosum in a freshwater environment.

PLHC-1세포주의 Comet assay를 이용한 하천 퇴적토의 생태독성평가 (Studies on Toxicological Evaluation of Freshwater Sediment using a PLHC-1 Cell Comet Assay)

  • 박정아;황인영;백승홍;김영숙
    • 환경생물
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    • 제29권1호
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    • pp.23-30
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    • 2011
  • In this study, the Comet assay (evaluation of DNA damage) used the fish hepatocellular carinoma cell, PLHC-1, was tried to the sediment extract obtained from freshwater to understand its applicability as a tool for monitoring sediment toxicity. In parallel, induced EROD (7-ethoxyresorufin- O-deethylase) activity and DNA damage (TEM values) in PLHC-1 cells were measured for establishing the tandem endpoints of the PLHC-1cell test to test the ecotoxicity of sediment. Among several study sites in a small river passed through downtown and industrial park area, one of them, site B, showed a higher level of EROD activity and DNA damage than other sites. It indicates that a tandem endpoints of PLHC-1 cells could be useful tools for assessing the toxicity of sediment. The sensitivity of Comet assay with PLHC-1 cells was a little higher than that with a blood cell of frog tadpoles to the solvent extract of sediment. According to the results, a PLHC-1 cell-Comet assay could be used as a useful tool for evaluating ecotoxicity of the freshwater sediment. In addition, more detailed studies are needed to the contaminated site.

First report of six Sordariomycetes fungi isolated from plant litter in freshwater ecosystems of Korea

  • Goh, Jaeduk;Mun, Hye Yeon;Jeon, Yu-Jeong;Chung, Namil;Park, Young-Hwan;Park, Sangkyu;Hwang, Hyejin;Cheon, Wonsu
    • 한국균학회지
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    • 제48권2호
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    • pp.103-116
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    • 2020
  • Freshwater ecosystems provide a complex environment for microorganisms. In this study, we isolated diverse fungal strains from plant litter in freshwaters. These strains were identified using molecular phylogenetic analyses of rDNA and/or other gene sequences (TUB, GAPDH, and EF1). In addition, we examined their morphological characteristics by microscopy and cultural characteristics on several media. We identified six previously unrecorded Sordariomycetes species in Korea, i.e., Colletotrichum godetiae, Discosia rubi, Robillarda sessilis, Monochaetia dimorphospora, Idriella lunata, and Phialemoniopsis endophytica. Of these, D. rubi and M. dimorphospora exhibited high extracellular amylase, lipase, and protease activities, suggesting that these fungal isolates might play an important role as decomposers in freshwater ecosystems. Plant litter could thus be a good source for isolating and investigating previously undocumented fungal species in freshwater environments.

낙동강 하구의 담수 방류와 표층 수온 및 염분 반응 : 계류형 센서 연속관측 결과 (Effect of Freshwater Discharge on the Nakdong River Estuary: Mooring Observations of Water Temperature and Salinity)

  • 김상일;윤석현
    • 해양환경안전학회지
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    • 제25권1호
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    • pp.89-95
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    • 2019
  • 낙동강 하구에서 연속관측 자료를 바탕으로 담수의 방류와 수온 및 염분의 시간에 따른 반응을 조사하였다. 낙동강 하구 서쪽 해역에 계류형 센서를 설치하고 2017년 4월 1일부터 2018년 3월 31일까지 10분 간격으로 수온과 염분을 측정하였다. 담수의 방류량은 평상시에 $200m^3\;s^{-1}\;d^{-1}$ 이하로 유지되었으나, 풍수기에는 $500{\sim}1000m^3\;s^{-1}\;d^{-1}$ 이상의 많은 양의 담수가 빈번하게 방류되었다. 담수의 방류는 대조기에는 간조를 전후하여 발생하였고, 소조기 동안에는 계속적으로 일어났다. 평상시에 수온과 염분은 소조기 동안 큰 변동 없이 안정되는 경향을 보이는 반면에, 대조기에는 방류주기에 따라 규칙적인 변동을 나타내었다. 연구기간 동안 염분은 평균 29이었으며, 평상시에 염분 농도는 평균 이상으로 유지되었고 일시적인 감소 이후에도 빠르게 회복되었다. 풍수기에는 약 3개월 동안 평균 이하의 저염환경이 지속되었다. 이러한 결과는 담수의 방류량뿐만 아니라 방류의 지속시간과 대량 방류의 빈도가 낙동강 하구의 표층 수온과 염분의 변동성에 영향을 미치는 중요한 요인이 된다는 것을 의미한다.

양식계 오염원 배출량 산정을 위한 원단위 설정 (Evaluation of Pollutant Load Unit Factor for Calculating Pollutants Emission in Aquacultural Farms)

  • 박재홍;박배경;류덕희;이재관
    • 한국물환경학회지
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    • 제29권5호
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    • pp.656-665
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    • 2013
  • This research was conducted to investigate pollutant load unit factor from aquacultural farms. Pollutant load unit factors were investigated on the 13 kinds of fish type, i.e., Trout, Leather Carp, Eel, Carp, Cartfish, Freshwater Eel, Crucian Carp, Colored Carp, Sturgeon, Marsh Snail, Sweetfish, Pond Snail, Eriocheir Sinensis. Water qualities in aquacultural farms were investigated wide range of values by fish type and pollutant items. High BOD and COD values were observed at the Leather Carp (Ponded water system), Cartfish (Ponded water system) and Freshwater Eel (Recirculating System). TOC and DOC values were relatively high at the Freshwater Eel (Recirculating System) and Eriocheir Sinensis (Extensive). Eel (Ponded water system) and Freshwater Eel (Recirculating System) produced high concentrated nutrient pollutants, i.e., T-N, T-P. Pollutant load unit factors are dependent on fish type, aquacultural type, water quality items, etc. If some fishes have similar basic unit values, those could be applied for TMDLs as a group of fish having same pollutant load unit. The water quality concentrations of post treatment facilities' (mainly reservoir tank) effluent were higher than those of fish raising bath because of extracting pollutant from sediment in the reservoir tank. Therefore, it needs to the management and regulations about post treatment facilities.

한국 담수어류의 보존 및 복원 전략 (Strategies for Conservation and Restoration of Freshwater Fish Species in Korea)

  • 강언종;;양현
    • 한국어류학회지
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    • 제21권sup1호
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    • pp.29-37
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    • 2009
  • The tiny fragment of freshwater body is providing home for huge biodiversity and resources for the existence of human. The competing demand for freshwater have been increased rapidly and it caused the declination of biodiversity in recent decades. Unlike the natural process of extinction in gradual progress, the current species extinction is accelerated by human activity. As a result many fish species are already extinct or alive only in captivity in the world and about fifty eight animal species are in endangered in Korea including eighteen freshwater species. Conservation of biodiversity is the process by which the prevention of loss or damage is attained, and is often associated with management of the natural environment. The practical action is classified into in-situ, or ex-situ depending on the location of the conservation effort. Recovery means the process by which the status of endangerment is improved to persist in the wild by re-introduction of species from ex-situ conservation population into nature or translocation of some population. However there are a lot of restrictions to complete it and successful results are known very rare in case. In this article the authors explore some strategies for conservation and restoration of freshwater fish species conducted in Korea for few years. The major causes are discussed in relation with the decline of freshwater fish diversity during few decades and some strategies are evaluated to advance the process of conservation. A study on the Korean bullhead, Pseudobagrus brevicorpus, is introduced as a case for ex-situ conservation and restoration in freshwater ecosystem.

BOX 모델을 이용한 금강 하구해역의 물질수지 산정 (Estimation of material budget for Keum river estuary using a Box Model)

  • 김종구;김동명;양재삼
    • 한국해양환경ㆍ에너지학회지
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    • 제3권4호
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    • pp.76-90
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    • 2000
  • 물질수송 해석을 위한 박스모델 형태의 물질수지모델을 이용하여, 주변의 많은 환경적 변화 요인을 내재하고 있는 금강하구를 대상으로 계절별 영양염 물질순환 특성을 평가하였다. 담수 유입 및 유출은 계절에 따라 약 4~14배의 큰 차이를 나타내었다. 물수지에 의한 담수유 출량은 1.014×10/sup 8/~12.566×10/sup 8/m³/month로 나타났으며, 담수유출량의 99.7%가 하천수의 유출에 의한 것으로 나타났다. 염분수지에 의해 계산된 담수존재량은 0.339×10/sup 8/~0.652×10/sup 8/m³이었고, 평균체류시간은 1.6~10.0일, 해수교환시간은 2.2~11.9일로 계산되었다. 평균체류시간은 계절별로 큰 차이를 보였는데 강우집중시기인 하계 풍수기에는 1.6일의 짧은 체류시간을 보인 반면 동계 갈수기에는 10.0일의 평균체류시간을 나타내었다. 영양염 수지로 계산된 DIP의 유입flux의 범위는 5.57~32.68ton/month이었고, DIN 유입flux는 234.93~2,373.39ton/month로 계산되었다. 영양염의 체류시간을 보면, DIP의 경우 1.1~6.4일의 범위를, DIN의 경우 1.8~10.9일의 범위를 보였고, 담수체류시간과 비교하면, DIP는 0.39~2.31배, DIN은 0.83~l.13배를 나타내었다. DIP의 경우 하계를 제외한 전 계절에서 담수 체류시간보다 짧아 DIP가 빠르게 순환되었으나, DIN의 경우 하계와 동계에 담수체류시간보다 긴 순환비를 보여 영양염이 축적됨을 알 수 있다.

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지리산 국립공원내 담수어류 분포 (Distribution of Freshwater Fish in Chirisan National Park)

  • 이승휘
    • 한국환경생태학회지
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    • 제5권1호
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    • pp.114-119
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    • 1991
  • 관광개발에 따른 심한 환경변화가 예상되는 지리산 국립 공원의 어족자원을 보호하기 위한 기초자료를 얻고자 이 지역의 어류분포상을 조사하였다. 국립공원내 하천에서 확인된 어종은 잉어과, 퉁가리과 및 농어과가 포함된 3과에 속하는 4종이었다. 우점종은 갈겨니였으나 이미 보고된 자료보다는 약간 감소추세을 보이고 있다. 따라서 이 지역에 대한 각별한 보호와 분별있는 관광개발이 요망된다.

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