• Journal of the Korean Society for Marine Environment & Energy
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• v.16 no.2
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• pp.82-87
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• 2013

Effects of material surface property, hydrophobic or hydrophilic, on the bio-fouling occurred on the bodies submerged in the sea water are investigated experimentally. 4 test models are used in the experiment, which includes aluminum foil in common use, AAO applied hydrophobic surface, HDFS coated hydrophobic surface and hydrophilic surface. Hydrophobic surfaces with numerous micro & nano-scale pillars on it seems to play very important role of preventing them from fouling in initial stage while the effects disappear in long term sense of fouling process. It is concluded that the surface hydrophobicity retards the initial fouling until the fouling thickness is smaller than the heights of the pillars on it but the effects diminish with the fouling proceeds so that the thickness grows bigger than the pillar heights.

• Journal of the Korean Society for Marine Environment & Energy
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• v.12 no.3
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• pp.157-164
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• 2009

In order to rehabilitate habitats for marine organisms in the slag dumping area, succession of benthic communities was monitored on artificial seaweed beds with transplantation of Ecklonia stolonifera from April 2004 to June 2005. Acinetospora critina was only primary dominated on steel frame in the first experiment (April 2004). A total of 15 species of seaweed were identified in the second experiment (June 2004). Enteromorpha intestinalis and Enteromorpha sp. were dominated, and Urospora penicilliformis, Ulothrix flacca, Cladophora sp., and Ulva pertusa were found on Ecklonia stolonifera fronds gradually with increasing time. This time was coincided with occurrence of benthic macrofaunas, molluscans and small fish species. The epiphytic benthic macrofaunas were dominated on amphipods, molluscans were Mytilus edulis, Thais clavigera, and fish species were Mugil cephalus, Pholis nebulosa. These results indicated that transplantation of Ecklonia stolonifera on artificial seaweed beds have been contributed on restoration habitats for benthic communities in the slag dumping area.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.4
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• pp.361-367
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• 2010

The use of antifouling(AF) paints is the effective method for the protection of underwater structures from the development of marine fouling organisms. The ban on harmful substances in antifouling paints requires the development of new antifouling strategies although Tributyitin (TBT) compound had been used extensively as an active ingredient Alternatives should be as effective as conventional paints but have lower toxicity. In the present study, a TBT-free self-polishing (Cu SPC) AF paint containing $Cu_2O$, a Cu free SPC AF paint, and a Foul-release silicone AF paint, which were commercially available, were examined to investigate environmental erects of leakage waters employing Sebastes shlegeli and Artemia. Survival rates were inversely proportional to the concentration of leakage waters from AF paints and the acute toxicity of SPC AF paints was relatively higher than that of foul release AF paints.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.92-92
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• 2003

본 연구는 부착규조류에 따른 부착성 요각류 Tigriopus japonicus의 nauplius 생산력을 알아보기 위하여 실시하였다. 실험에 사용된 T. japonicus는 부산 동백섬 부경대학교 수산과학연구소 부근에 있는 tidal pool에서 동물성부유생물망으로 채집하였다. 먹이생물로는 부경대학교 한국해양 미세조류 은행에서 보관중인 부착규조류 중 중형종인 Caloneis schroder를 대표종으로 이와 크기가(14.8~27.5$\mu\textrm{m}$) 유사한 종들을 대상으로 형태를 현미경 하에서 관찰하고, 지역과 분리일자 등을 고려하여 유사종을 선별한 후 최종적으로 종의 유전적 유사성을 밝히기 위하여 RAPD-PCR (random amplified polymorphic DNA polymerase chain reaction)을 실시하였다. 이 중 Caloneis schroder와 유전적으로 유사성이 낮은 Navicula spp. (KMCC B-245, 393, 394, 581) 4종을 선별하여 T. japonicus의 먹이로 사용하여 포란한 암컷의 nauplius 생산력을 3반복 조사하였다. Genomic DNA는 대부분의 종에서 성공적으로 검출되었으며, 종에 따라 PCR 증폭산물이 나타나지 않은 경우도 있었으므로, PCR 산물이 나타난 종에 대해서만 분석하였고, 증폭된 DNA band는 대부분 크기 0.5~2.0kb 범위에서 나타났다. 실험에 사용된 부착규조류 간의 유사성을 알아보기 위하여 similarity matrix를 분석한 결과 F값의 범위는 0.00에서 1.00까지 였으며, Caloneis schroder와 유사성이 낮은 종들에 비하여 유사성이 높은 종들이 더 많이 나타났다. 이들을 먹이로 하여 포란한 T. japonicus의 실험구별 nauplius 평균 개체수를 살펴보면, KMCC B-394가 255.7마리로 가장 높았던 반면 KMCC B-581가 29.7마리로 가장 낮았다. 그 외 KMCC B-245가 120.0마리, KMCC B-393가 76.0마리, Caloneis schroder가 32.3마리 각각 나타났다. 이와같은 결과를 볼 때 T. japonicus의 nauplius 생산력은 규조 종에 따라 큰 차이가 있는 것으로 판단된다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.2
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• pp.249-265
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• 2019

A passive sampler is one of the promising methods to easily and more accurately predict the free dissolved and bioavailable concentration ($C_{free}$) in seawater or pore water in sediments. In Europe and the United States, the use of passive samplers has been highly encouraged for more accurate marine environmental risk assessment. However, long deployment time in the field causes problems such as biofouling of the samplers, so there are few studies using passive samplers in Korea. Therefore, we review the principle and basic characteristics of the passive sampler for persistent organic pollutants, and introduce various improvement cases for the field applications of the passive sampler.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.5
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• pp.476-479
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• 2002

We observed the succession and appearence species of the marine benthic diatoms for the effective seed production of shellfish culture on wave plates in indoor mass culture tanks. Every five days, the existence species and densitiy of diatoms were counted during the 20 culture days. Experimental conditions were 8.5 $\pm$ 0.3$^{\circ}C$ of water temperature, 1.0250$\~$1.0260 of specific gravity, 2,200$\~$13,000 lux of light intensity. The total density of appearence species was rapidly increased with the lapse of time. However, the number of appearence species decreased on the 20th day. The diatoms observed were 10 species; Navicula sp. of, viridula, Cylindrotheca closterium, Licmophora sp., Pleurosisma normnii, Bacillaria Paradoxa Asterionella glacialis, Stephanopuis sp. cf, turris, Entomoneis sp., Odontella aurita and Cocconeis sp, cf, scutellum. Of them, Navicula sp, of, viridula was most dominant throughout the experiment.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.2
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• pp.136-143
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• 1999

To understand the growth of attached microalgae to the immersed artificial surfaces in seawater with exposure time, chlorophyll a (chl a) concentration and abundance of attached microalgae to glass slides, and primary productivity and chl a concentration on coverglasses were investigated in Incheon Harbour in May, June 1996 and January-February 1997. Chl a concentrations of microalgae and abundances of diatoms attached to glass slides reached 62.5 mg chl a $m^{-2}$ and $144{\times}10^3$ cells $cm^{-2}$, respectively, during the study period. Chl a concentrations increased with exposure time, and they were significantly correlated with the abundances of attached diatoms ($r^2=0.79$, p<0.001). The chl a concentrations of attached micro algae on coverglass reached the maximum values of 31.1 mg chl a $m^{-2}$ and 65.4 mg chl a $m^{-2}$, and then decreased in May, June 1996. But in January-February 1997, the chl a concentration increased continuously up to 98.9 mg chl a $m^{-2}$. The primary productivity reached the maximum values of 63.1 mgC $m^{-2}\;h^{-1}$, 347.0 mgC $m^{-2}\;h^{-1}$ and 78.3 mgC $m^{-2}\;h^{-1}$, respectively, in May, June and January-February. The primary productivity in May and June varied in accordance with chl a concentrations. But in January-February, the primary productivity decreased from 26 days of exposure while chl a concentration continued to increase. Two cases that primary productivity decreased abruptly seemed to be caused by decrement of chl a and light specific $P^B$ (chl a specific primary productivity) (May and June) and by decrement of light specific $P^B$ due to photoinhibition (January-February). The results of present study indicated that chl a concentrations and the primary productivity of microalgae attached to artifical surfaces immersed in seawater would expedite analysis of dynamics of biomass and physiological status of attached microalgae during biofilm formations.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.1
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• pp.18-29
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• 2019

ROV surveys were conducted using 500 meter mini class ROV with HD video camera, 2 LED lights, a simple manipulator and 8 thrusters near the Dokdo and Simheungtaek seamount. Total six dives have been conducted using the ROV "V8 SII" from Sweden and ROV's support ship, "KOSAL V" at 4 stations between 45 and 370 meters with diving time ranged from 30 to 120 minutes. Dense communities of sea anemone (Actinostolidae sp.) and ophiuroids (Ophiuridae sp.) on the surface of rocky bottom and snow crab on the soft bottom with muddy-sand were observed at northwestern part of Simheungtaek seamount. We obtained the following results 1) habitats information for snow crab, one of the major fisheries resources, and deep-sea fauna, 2) observation on the specific topography and sediment conditions, 3) observation of the seabed surface covered with the discarded fishing gears. This study represents the first report of in situ visual observation of deep-sea organisms and their habitats near the Dokdo slopes and flat top of the Simheungtaek seamount in the East Sea. These results indicated that immediate oceanographic survey using the mini class ROV is available in the East Sea.

• Ocean and Polar Research
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• v.45 no.3
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• pp.125-140
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• 2023

We investigated meiofaunal biofouling (40-1,000 ㎛) on stranded marine plastic debris (hereafter MPD) collected from 8 coastal areas highly affected by plastic pollution located in the southern part of Korea during June, 2021, in order to analyze the abundance and composition of MPD associated organisms. A total of eight shapes of MPD was collected and classified into four types of plastics (LDPE, PET, PP and EPS) based on Resin Identification Coding System. Meiofounal biofouling was identified into 35 taxa belonging to 11 phylum, 10 classes and 12 order, and were numerically dominated by harpacticoids (EPS: 21.6%, PP: 27.1%), nematodes (LDPE: 23.2%) and foraminiferans (PET: 29.6%). Surface area of MPD was negatively correlated with abundances of organisms on the plastic debris (r = -0.487, p < 0.05, n = 24), indicating that abundances (avg. 3,225 inds. 0.1 m^-2) on the smallest area of PP debris (avg. 0.0208 m² ) were higher than those (avg. 50 inds. 0.1 m^-2) on the largest area of LDPE debris (avg. 0.4029 m^-2). Whereas, there was no correlation between surface area of MPD and the number of taxa on the debris (r = 0.147, p = 0.49, n = 24). These results showed that higher abundances of meiofaunal biofouling were observed on the PP material debris than those on the other debris collected from eight hot spots of the southern coastal waters in Korea, associated with not only polymer type and surface area of the PP debris, but also possibly surface microstructure of the PP debris.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.46-146
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• 2003

해양환경의 대표적 오염물질인 PAHs가 양식굴의 생리대사에 미치는 영향을 파악하고자, 서로 다른 PAHs 농도에 노출된 굴의 여수율, 호흡율, 배설율 및 동화율의 변화를 조사하였다. 부착생물을 깨끗하게 제거한 굴을 실험실로 옮겨 3일정도 순치시키고, 이후 각각의 0, 50, 100, 200ppb의 농도별로 약 10일간 미리 노출시켰다. 이후 각 개체별로 2L 들이 2$0^{\circ}C$항온수조에서 0.2$\mu\textrm{m}$ 여과해수를 사용하여 실험하였다. 여수율은 Chaetoceros simplex를 지표생물로 하여 수조내 시간당 감소율을 구하여 Kim(1995)의 식에 의해 구하였다. 호흡율은 유동파라핀으로 외부와의 공기접촉을 단절시키고, 수조내 단위시간당 DO meter로 산소변화를 측정하여 Widdows and Johnson(1988)의 식을 변형하여 계산하였다. 배설율은 단위시간동안 수조내 NH$_4$-N 농도 증가량으로 조사하였고, NH$_4$-N은 HACH Inc.에서 제공하는 측정법을 따랐다. 여수율은 500ppb에서 다소 영향을 받아 증가하였다. 호흡율과 배설율은 노출농도가 증가함에 따라 증가하였지만, 50ppb와 100ppb에서는 다소 차이가 없었다. 따라서 양식굴이 PAHs와 같은 오염물질에 노출되었을 경우, 초기에는 여수율의 변화는 없고 배설율과 호흡율이 상승하여 체내 에너지 요구량이 증가하는 것으로 생각된다.