• Korean Journal of Environmental Biology
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• v.40 no.3
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• pp.255-266
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• 2022

In crustaceans, molting is regulated by interactions between ecdysteroid and juvenile hormone (JH) signaling pathway-related genes. Unlike the ecdysteroid signaling pathway, little information on the role of JH signaling pathway-related genes in molting is available in zooplanktonic crustaceans. In this study, three genes (juvenile hormone acid O-methyltransferase (JHAMT), methoprene-tolerant (Met), and juvenile hormone epoxide hydrolase (JHEH)) which are involved in the synthesis, receptor-binding, and degradation of JH were identified using sequence and phylogenetic analysis in the brackish water flea, Diaphanosoma celebensis. Transcriptional changes in these genes during the molting cycle in D. celebensis were analyzed. Sequence and phylogenetic analysis revealed that these putative proteins may be functionally conserved along with those of insects and other crustaceans. In addition, the expression of the three genes was correlated with the molting cycle of D. celebensis, indicating that these genes may be involved in the synthesis and degradation of JH, resulting in normal molting. This study will provide information for a better understanding of the role of JH signaling pathway-related genes during the molting process in Cladocera.

• The Korean Journal of Quaternary Research
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• v.33 no.1_2
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• pp.59-68
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• 2021

The maximum upper limit of seawater inflow can be recognized by the acid-resistant dinoflagellate cysts and salt-marsh pollen encountered from surface samples in the lower reach of Jujin Stream facing Gomso Bay. Based on their relative yield ratio, the downstream area of Jujin Stream could be further subdivided into coastal marine, brackish-upper limit brackish, and freshwater environments. The abundance of dinoflagellate cysts from JJR-41 to JJR-36 sites reflects that this area is a coastal marine. In the section between JJR-35 and JJR-5 sites, dinoflagellate cysts associated with pollen derived from riparian or salt-marsh (e.g., reeds and sedges) appear to reflect the brackish environments. It may be indicated that dinoflagellate cysts appear up to the JJR-4 site, which is the maximum upper limit where seawater flows up to this point at high tide. This analysis is relatively well corresponding to the hypothetical inundation map showing the maximum flooding area where seawater can flow at high tide.

• 보존과학연구
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• s.7
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• pp.265-277
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• 1986

The degradation of wood is maimly caused by biological and thermal factor. In general, the field of wood preservation can be divided into two broadcategories; namely the deterioration, protection of wood, and the teatment of wood with preservatives. Wood in sea or brackish water incurs marine borer damage, consisting of attack by marine animal and also wood on land suffers severely from insect damage. But the largest wood degradation is caused by microorganism. Animals that attack wood in a marine environment are especially destructive in warm water-regions, little was achieved in their control recently. Therefore this manuscript only introduce the importance of wood deterioration caused by marine animal.

• 한국해양학회지
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• v.20 no.2
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• pp.61-66
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• 1985

A mysid, Neomysis awatschensis(Brandt), which distributes abundantly in brackish lakes, estuaries and salt marshes along the southern and western coast of Korea, from Kimhae to Inchon is described and recorded as new to Korea. The world distribution of the species are also revised with short discussion.

• Ocean Science Journal
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• v.42 no.4
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• pp.255-267
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• 2007

Three brackish-water harpacticoid species belonging to the family Cletodidae are reported from the salt marshes in South Korea: Limnocletodes behningi Borutzky, 1926, L. angustodes Shen and Tai, 1963 and Kollerua longum (Shen and Tai 1979). Two genera, Limnocletodes and Kollerua, and the three species are newly added to Korean fauna. This paper deals with the redescription and systematic accounts of them, with detailed illustrations.

• Journal of Species Research
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• v.6 no.spc
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• pp.15-25
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• 2017

Twelve ciliates were collected from freshwater, marine, and brackish water habitats in Korea and taxonomic descriptions are provided based on observations of living cells and protargol-impregnated specimens. These ciliates, recorded for the first time in Korea, were classified into 12 genera, 11 families, 10 orders, and five classes. We provide brief descriptions and remarks, including microphotographs, for the 12 ciliates: Allotricha mollis, Amphileptus eigneri, Didinium gargantua, Holophrya teres, Lacrymaria marina, Novistrombidium apsheronicum, Pelagostrobilidium conicum, Pseudochilodonopsis fluviatilis, Pseudourostyla subtropica, Strombidium conicum, Urocentrum turbo, and Uronema marinum.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.211-212
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• 2000

유공충은 껍질(test)을 가지는 원생동물로 기수역(brackish) 내지는 해양에 널게 분포하고 있다. 대부분 석회질 혹은 사질(arenaceous)의 껍질로 구성되어 있으며, 해양퇴적물의 중요한 생물원 요소가 되고 있다(Matoba, 1975). 유공충은 서식환경에 따라 종조성을 달리하거나 종내변이(variety 혹은 ecophenotype)를 보이며 환경의 변화에 민감하게 반응한다. 본 연구에서는 한반도 동남부 연안해역의 내 대륙붕 니질대(nearshore mud belt) 및 영일만에 분포하는 저서성유공충의 분포특성을 파악하고 저질환경인자에 대한 반응 종을 탐색함으로써 연안환경에 서식하는 유공충의 환경지시자를 밝히고자 한다. (중략)

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.25-28
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• 2004

In recent years, membranes have become fully or partially integrated into all facilities that produce drinking water since membrane processes can resolve technically complex and, at times, conflicting requirements related to compliance with multi-contaminant regulations. However, NF or RO technologies are hydraulically limited by the feed water quality that causes the fouling in a membrane system. In particular, NF or RO systems involved in surface water treatment generally require extensive pretreatment for controlling membrane fouling.(omitted)

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.199-202
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• 2004

Membrane technology is widely employed as a means of producing various qualities of water from surface water, well water, brackish water and seawater. This is also used in industrial wastewater treatment and its recycling process. A large volume of wastewater is generated by the steel industry. Presently, the treated wastewater from the steel industry cannot be recycled, because some of its components cause either direct or indirect problems.(omitted)

• Parasites, Hosts and Diseases
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• v.46 no.2
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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.