• 제목/요약/키워드: brackish waters

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Growth and Reproductive Biology of the Freshwater Shrimp Exopalaemon modestus(Decapoda: Palaemonidae) in A Lake of Korea

  • Oh, Chul-Woong;Suh, Hae-Lip;Ma, Chae-Woo;Jeong, In-Ju;Kim, Jang-Young
    • 한국어업기술학회:학술대회논문집
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    • 한국어업기술학회 2001년도 추계 수산관련학회 공동학술대회발표요지집
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    • pp.313-314
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    • 2001
  • The palaemonid shrimp Exopazaemon modestus inhabits the freshwater of the Indo-West Pacific, Siberia, Manchuira, Korea, China, Taiwan (Holthuis, 1980) and is abundant in the fresh water areas of southwest of Korea. Palaemonid shrimps are adapted to a variety of habitats in freshwater, brackish and marine environments. They play important role in the ecosystem of fresh, brackish and marine waters, acting as predators feeding on algae, detritus, crustaceans and meiofauna (Bell and Coull, 1978) and in turn, as preys for fishes and other predators (Anderson, 1985). (omitted)

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Taxonomic study of the genus Achnanthes (Bacillariophyta) in Korean coastal waters

  • Lee, Sang Deuk;Park, Joon Sang;Lee, Jin Hwan
    • Journal of Ecology and Environment
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    • 제36권4호
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    • pp.391-406
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    • 2013
  • A study on the fine structure of the genus Achnanthes species (Bacillariophyceae) is carried out at 92 stations for taxonomic purposes from January 2009 to April 2013 in Korean marine water, freshwater and brackish water. Twelve Achnanthes species are identified based on a variety of taxonomic characters by means of light microscopy and scanning electron microscopy. Of these, seven species, Achnanthes cocconeioides, A. groenlandica, A. javanica, A. kuwaitensis, A. parvula, A. pseudolongipes, and A. yaquinensis, are newly recorded in Korean waters. All 12 species are documented concerning a taxonomic key, description, distribution, seasonality, remarks and photographs. Twenty three Achnanthes taxa are identified in the survey.

New Record of Diatom Species in Korean Coastal Waters

  • Lee, Sang Deuk;Park, Joon Sang;Lee, Jin Hwan
    • 환경생물
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    • 제30권3호
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    • pp.245-271
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    • 2012
  • A study on the indigenous diatoms was carried out at 103 sites during August 2008 to April 2011 from the marine and the brackish waters in Korea. A fine structure of small-sized diatoms was examined using a light and scanning electron microscopy. Sixty species of diatoms were newly identified and composed of 3 class, 6 subclass, 16 order, 21 family and 39 genus. The detailed nomenclatures, references, photographs and distributions were here reported. Of 60 species, the most frequent species was Tryblionella coarctata appearing 24 times, and 22 times followed by Thalassiosira lacustris, Cocconeis stauroneiformis was 20 times. In the level of genus, Chaetoceros, Parlibells and Thalassiosira were included 4 species, Actinocyclus, Minidiscus and Licmophora were included 3 species. This study will provide the knowledge of the diversity level of diatom in Korea, the knowledge is important on the diatoms for further studies.

Intra- and Interspecific Variation in the Ribosomal Internal Transcribed Spacers and 5.8S rDNA among three species of Pseudodiaptomus (Calanoida, Pseudodiaptomidae) from Korean Estuarine Waters

  • Soh, Ho-Young;Suh, Hae-Lip;Yoon, Yang-Ho;Park, Sang-Duk;Kwon, Soon-Yoo
    • 한국어업기술학회:학술대회논문집
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    • 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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    • pp.437-438
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    • 2001
  • Species of the genus Pseudodiaptomus are reported as the major constituents in the fresh or brackish waters in the northeastern Asia (Suh et al., 1991; Oka et al., 1991). Of these species, P. inopinus (Burckhardt) and P. poplesia (Shen) are particularly numerous in spring and autumn (Suh et al., 1991; Shen and Song, 1979). Recently. we found a presence of two types of Pseudodiaptomus inopinus during the course of investigation on zooplankton from Korean estuaries. (omitted)

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Prevalence of Zoonotic Metacercariae in Two Species of Grouper, Epinephelus coioides and Epinephelus bleekeri, and Flathead Mullet, Mugil cephalus, in Vietnam

  • Vo, Dung The;Murrell, Darwin;Dalsgaard, Anders;Bristow, Glenn;Nguyen, Dung Huu;Bui, Thanh Ngoc;Vo, Dung Thi
    • Parasites, Hosts and Diseases
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    • 제46권2호
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    • pp.77-82
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    • 2008
  • Fishborne zoonotic metacercariae have not been reported from brackish water and marine fish from Vietnam waters although these parasites are common in the country's freshwater fish. Both wild-caught and cultured grouper (Epinephelus coioides and Epinephelus bleekeri), and mullet (Mugil cephalus) from brackish and marine waters located in Khanh Hoa province in central coastal Vietnam were examined, and found positive for zoonotic trematode metacercariae. From grouper, Heterophyopsis continua and Procerovum varium were recovered. The prevalence of H. continua ranged from 2.0 to 6.0% and that for P. varium ranged from 11.6 to 15.8%. Mullet were infected with Pygidiopsis summa and H. continua; both of these species are new records for Vietnam. The prevalence of P. summa in mullet was generally high, ranging from 17.6 to 75.5%, and was significantly higher than the prevalence of H. continua (2.5 to 32.4%). There were no significant differences in the prevalence of metacercariae between grouper from natural or cultured habitats, indicating that the highest risk of infection occurs in the wild-caught state prior to their placement in culture. Further, there was no difference in metacercarial prevalence between the 2 species of grouper. Infected wild-caught seed were only observed from January to October. Monthly variation in prevalence suggests seasonal variation in mullet infections occurs in this region with the highest transmission taking place from October to December. Basic investigations on the ecology and epidemiology of these intestinal flukes need to be carried out to determine their significance as a public health problem and the aspects of their biology that may be vulnerable to control interventions.

서해안과 남해안의 기수역과 연안해역에서 우점하는 요각류 곁노벌레과(Paracalanidae) 2종의 수온과 염분에 따른 분포 특성 (Distribution Characteristics of Two Dominant Paracalanids on Temperature and Salinity in the Brackish and Coastal Waters from the West and South Coasts of Korea)

  • 문성용;서민호;서호영
    • 환경생물
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    • 제29권1호
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    • pp.11-16
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    • 2011
  • 서해안과 남해안의 기수역과 연안해역에서 우점하는 곁노벌레과(Paracalanidae) 2종 간의 수온과 염분에 따른 출현 양상을 파악하고자 영광 인근해역을 중심으로 2007년 가을철, 2008년 겨울철, 봄철, 그리고 여름철에 걸쳐 사계절조사를 실시하였다. Bestiolina coreana는 봄철과 겨울철에 출현하지 않았으며, Paracalanus parvus s. l.는 연중 출현하는 것으로 나타났다. 이들 종간의 수온과 염분에 따른 출현 양상에서는 수온 $20^{\circ}C$ 이상과 32 psu 미만으로 낮아지는 시기에는 P. parvus s. l.보다 B. coreana의 개체군이 월등하게 높게 유지되는 것으로 나타나 결과적으로 계절에 따른 수온과 염분 변동이 두 종의 출현 양상에 영향을 미칠 수 있는 중요한 단서로 제공될수 있음을 의미한다.

한국 연안의 요각류 중 Acartia clausi로 분류되어지고 있는 종에 대한 재검정 및 분포에 대한 연구 (Taxonomic Re-examination and Distribution of Copepods known as Acartia clausi in the coastal waters of Korea)

  • 강영실;이삼석
    • 한국수산과학회지
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    • 제23권5호
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    • pp.378-384
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    • 1990
  • 한국 연안에서 보고되고 있는 Acartia clausi를 부산 연안역에서 채집된 종으로써 재검정하였다. 그 결과 지금까지 A. clausi로 분류되어졌던 종이 Acartia omorii이거나 A. hudsonica임이 밝혀졌다. 수컷의 경우, 제5각 오른쪽 세번째 마디절 내측에 있는 융기부의 형태에서 두종간의 뚜렷한 차이를 찾을 수 있다 A. omorii는 융기부의 아랫부분이 만곡되어 있으며, A. hudsonica는 원형으로 돌출되어 있다. 암컷의 경우, 생식절의 폭에 대한 길이의 비가 두 종간 중요한 분류 형질이 된다. 또한, A. omorii와 경우, 후제부의 두번째 마디절 등쪽 끝에 $1\~3$개의 소극을 가진 것이 특징이다. 한국 연안 8개의 지점에서 분포를 파악해 본 결과 A. omorii는 모든 조사지점에서 출현하였고, A. hudsenica는 부산 연안역에서만 출현하였다.

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The Utility of Measuring Assimiliable Organic Carbon (AOC) as an Indicator of Biostability in Distribution Systems for Finished Water

  • Chang, Young-Cheol;Toyama, Tadashi;Jung, Kweon;Kikuchi, Shitaro
    • 한국환경보건학회지
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    • 제32권6호
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    • pp.539-542
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    • 2006
  • The objective of this paper is to compare the applicability of assimilable organic carbon (AOC) or biodegradable dissolved organic carbon (BDOC) for quantifying biodegradable organic material (BOM) and bio-stability in distribution systems for a variety of finished waters. The study the data is derived from was part of an AWWARF and Tampa Bay Water tailored collaboration project to determine the effect of blending different waters on distribution system water quality. Seven different finished waters were produced from surface, ground, or brackish water on site and fed 18 independent pilot distribution systems (PDSs), either as single finished water or as a blend of several finished waters. AOC and BDOC have often been used as indicators of bacterial regrowth potential in distribution systems. In this study, AOC was the more useful assay of the two for the BOM concentrations observed in the PDSs. BDOC did not distinguish BOM while AOC did at the low BOM levels from many of the advanced treatments (e.g. RO, $O^3/BAC$). AOC in contrast allowed much more meaningful calculations of the consumption or production of AOC as the blends passed through the PDSs even for very low BOM blends. In addition, meaningful trends corresponding to changes in heterophic plate count (HPC) were observed for AOC but not for BDOC. Moreover, AOC stability was associated with waters produced from advanced membrane treatment.

Effect of Distribution System Materials and Water Quality on Heterotrophic Plate Counts and Biofilm Proliferation

  • 장영철;정권
    • Journal of Microbiology and Biotechnology
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    • 제14권6호
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    • pp.1114-1119
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    • 2004
  • The biofilms on pipe walls in water distribution systems are of interest since they can lead to chlorine demand, coliform growth, pipe corrosion, and water taste and odor problems. As such, the study described in this paper is part of an AWWARF and Tampa Bay Water tailored collaboration project to determine the effect of blending different source waters on the water quality in various distribution systems. The project was based on 18 independent pilot distribution systems (PDS), each being fed by a different water blend (7 finished waters blended in different proportions). The source waters compared were groundwater, surface water, and brackish water, which were treated in a variety of pilot distribution systems, including reverse osmosis (RO) (desalination), both membrane and chemical softening, and ozonation-biological activated carbon (BAC), resulting in a total of 7 different finished waters. The observations from this study consistently demonstrated that unlined ductile iron was more heavily colonized by a biomass than galvanized steel, lined ductile iron, and PVC (in that order) and that the fixed biomass accumulation was more influenced by the nature of the supporting material than by the water quality (including the secondary residual levels). However, although the bulk liquid water cultivable bacterial counts (i.e. heterotrophic plate counts or HPCs) did not increase with a greater biofilm accumulation, the results also suggested that high HPCs corresponded to a low disinfectant residual more than a high biofilm inventory. Furthermore, temperature was found to affect the biofilms, plus the AOC was important when the residual was between 0.6 and 2.0 mg $Cl_2/l$. An additional aspect of the current study was that the potential of the exoproteolytic activity (PEPA) technique was used along with a traditional so-called destructive technique in which the biofilm was scrapped off the coupon surface, resuspended, and cultivated on an R2A agar. Both techniques indicated similar trends and relative comparisons among the PDSs, yet the culturable biofilm values for the traditional method were several orders of magnitude lower than the PEPA values.

방조제 건설 중인 2001-2002년 새만금 하구역 어류 종조성의 계절 변동 (Seasonal Variation in Species Composition of Fish in the Estuary of Saemangeum Waters during the Construction of a Dike in 2001-2002)

  • 이태원;문형태;김광천
    • 한국수산과학회지
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    • 제36권3호
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    • pp.298-305
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    • 2003
  • Seasonal variation in species composition of fish in the estuary of Saemangeum water in the western coast of Korea was determined using seasonal samples collected by an otter trawl from April 2001 to February 2002. Species compositions did not differ significantly among the 4 stations (p>0.05, Wilcoxon signed-rank test). The cumulative number of species and species diversity (H') approached asymptote after four 30-min trawl hauls. Therefore 30-min trawl samples from each of the four stations were pooled to represent each season. A total of 45 species 2758 individuals and 30,346.8 g of fish were collected during the study period. Of the fish collected Leiognathus nuchalis, Synechogobius hasta, Neosalanx jordani, Konosirus punctatus and Chaeturichthys stigmatias predominated in abundance accounting for $68\%$ of the total number of individuals. Seasonal variation of fish abundance showed a similar trend to those of the other western coastal waters of Korea. The resident species were collected only in spring and autumn. Number of species and biomass were highest in summer due to the catch of many migrating species. In winter catch amount was low, and only 7 species were collected.. Brackish water fishes were more abundant in the study area, and Johnius grypotus and Cynoglossus joyneri were not premominated compared to the other coastal waters. This difference in species compositions may be related to the lower salinity in this estuarine habitat than in the other western coastal waters of Korea.