Effects of climate change and Cochlodinium bloom in Korean coast

Moonho Son,Weolae Lim,Woojin Go 한국수산과학회 양식분과 2021 한국수산과학회 양식분과 학술대회 Vol.2021 No.4

살조물질과 황토를 이용한 적조생물 제어에 따른 광합성 효율 및 전자전달율의 차이

손문호(Son, Moonho),백승호(Baek, Seung-Ho) 한국산학기술학회 2015 한국산학기술학회논문지 Vol.16 No.4

유해 유독 적조생물의 대발생은 해양생물 건강성과 수산어족자원에 심각한 피해를 입힌다. 본 연구에서는 미세조류의 대발생을 억제하기 위해 개발된 Thiazolidione 유도체(TD49)와 현장에서 적조생물을 제어하기 위하여 살포되는 황토에 대한 살조능을 조사하였다. 아울러 적조생물 생사판별과 관련된 자가영양생물의 광합성에 영향을 미칠 수 있는 활성엽록소(activity Chl. a), 광합성효율(Fv/Fm), 전자 전달율(electron transport rate, ETR)등을 평가하였다. 대상적조생물은 유해조류 3종과 비유해 조류 1종을 선택하였으며, 유해조류는 침편모조류 Heterosigma akashiwo, Chattonella marina와 더불어 와편모조류 Heterocapsa circularisquama를 비교하였고, 비유해조류는 은편모조류 Rhodomonas salina에 대하여 평가하였다. 유해조류 3종 은 살조물질(TD49)에 의하여 빠른 시간에 세포가 파괴되어 우수한 살조 효과(>80%)를 보인 반면, 황토에 관해서는 살조효율 이 30%이하로 낮게 나타났다. 또한 TD49에 대한 유해조류 3종의 살조효율은 H. circularisquama> C. marina> H. akashiwo 순으로 높게 나타났으며, 광합성 효율 및 전자전달율 또한 극히 낮게 나타나, 광합성에 치명적인 영향을 미치는 것으로 사료되 었다. 반면, 유해조류 3종에 관해서 황토에 대한 광합성 효율과 전자전달율은 대조군과 유의한 차이를 보이지 않았다(p>0.01). 비유해종 R. salina 은 대조군에 비하여 TD49와 황토의 살조 효과, 광합성효율 및 전자전달율의 차이는 명확하게 나타나지 않았고, 오히려 TD49물질에서 성장에 긍정적인 영향을 미치는 것을 확인하였다. 결과적으로 본 연구에서 TD49물질은 유해적 조 생물을 선택적으로 제어 할 수 있으며, 현장 적용시 우수한 살조 효과를 가질 수 있을 것으로 판단된 반면, 황토는 적조생물 제어에 적합하지 않을 것으로 사료되었다. The development of worldwide harmful algal blooms(HAB) is a serious problem for public health and fisheries industries. To evaluate the algicidal impact on the HAB species, algicide thiazolidinedione derivative (TD49) and yellow clay were examined, which is focus on assess the algicidal effects and inhibition to photosynthesis of HAB species. To obtain the detailed information, we analyzed the viability of target species related to activity Chl. a, photosynthetic efficiency(Fv/Fm), and electron transport rate(ETR). Culture experiment was conducted to evaluate the algicidal effects of three harmful species(raphidophyceae Heterosigma akashiwo, Chattonella marina, and dinophyceae Heterocapsa circularisquama) and one non-harmful species (cryptophyceae Rhodomonas salina). Our experiments revealed that three HAB species were easily destroyed of the cell walls after TD49 dosing. Also, they had significantly reducing values of active Chl. a, Fv/Fm, and ETR, due to the damage of photosystem II by inter-cellular disturbance. As a result, the algicidal effect(%) for the three HABs were as follows, in the order of greatest to the least: H. circularisquama> C. marina> H. akashiwo. However, the algicidal effect for yellow clay remained to be <30% (p>0.01), implying that it may not have damaged the photosystem II. On the other hand, non-HAB R. salina was promoted at both TD49 and yellow clay treatments. Our results demonstrated that the TD49 is a good agent for the control of HABs H. akashiwo, C. marina, and H. circularisquama, whereas the yellow clay would not be suitable for the field application based on our experimental results.

춘계 진해만에서 농도 구배로 첨가한 영양염에 의한 식물플랑크톤 성장반응과 군집구조의 명확한 특징

손문호(Son, Moonho),백승호(Baek, Seung-Ho) 한국산학기술학회 2015 한국산학기술학회논문지 Vol.16 No.10

본 연구는 진해만에서 2010년 부영양화해역(St.1)과 빈영양화해역(St.22)에서, 2011년에는 부영양화해역(St.1, St.5), 중영양화해역(St.19), 빈영양화해역(St.22) 등 해역의 특성이 다른 정점에서 영양염농도구배(Nitrate: 0, 1, 5, 10, 20, 50, 100 μM; Phosphate: 0, 0.1, 0.5, 1, 2, 5, 10 μM)에 따른 식물플랑크톤의 성장반응 및 군집구조의 특성을 파악하였다. 2010 년 St.1에서 질산염과 인산염첨가군에서는 농도구별에 따른 식물플랑크톤성장의 차이를 보였으나(One-way ANOVA:P<0.01), St.22에서는 영염첨농도구배에 따른 영양염첨가효과가 명확하지 않았다. 2010년 St. 1의 질산염 첨가군에서 와편모조류 Heterocapsa triquetra가 우점하였고, 인산염 실험군에서는 규조류 Pseudo-nitzchia spp.가 각각 우점하였다 진해만 중앙의 빈 영양수계 St. 22에서는 질산염농도가 10 μM 전 후에서 Chaetoceros spp.가, 20 μM에서 Thalassiosira spp.가, >50 μM 에서 Pseudo-nitzchia spp. 가 각각 우점하였고, 인산염 첨가시 2 μM 이하에서는 Cylindrotheca spp.로, 5 μM 이상에서는 Pseudo-nitzchia spp.로 우점하였다. 2011년에는 4해역 모두 영양염농도구배에 따른 식물플랑크톤 성장의 명확한 차이를 보였 다(One-way ANOVA:P<0.01). 하지만, 정점1, 5, 19에서는 식물플랑크톤의 성장이 2일 후부터 점차적으로 증가하였으나, 정점 22에서는 실험 6일후부터 반응하였고, 이는 낮은 영양염농도에 적응된 생물군에 갑작스럽게 영양염이 공급되어도 성장 지연 현상이 일어날수 있다는 것을 의미한다. 식물플랑크톤의 우점종은 정점1의 낮은 영양염농도에서는 Eucampia spp., Chaetoceros spp.가 높게, 높은 영양염농도에서는 Skeletonema spp.와 Thalassiosira spp.로 나타났다. St. 5에서는 Skeletonema spp.가 우점하였고, St.19에서는 Chaetoceros spp.와 Skeletonema spp.도 상대적으로 높은 비율을 차지하였다. 반면, St. 22에서 는 Thalassiosira spp.가 높은 점유율을 보였다. 결과적으로 영양염특성이 다른 해역에서 추가적으로 첨가한 영양염은 영양염 농도구배에 따라서 식물플랑크톤의 우점종 및 종조성을 차이를 보였고, 이는 각각의 해역의 특성에 따라서 식물플랑크톤의 현존량 및 우점종의 차이가 명확하게 나타나는 것을 잘 대변할 수 있는 중요한 근거라고 판단된다. In order to estimate the characteristics of the growth and composition of phytoplankton according to the available nutrients, we added nitrate (0, 1, 5, 10, 20, 50, 100 μM) and phosphate (0, 0.1, 0.5, 1, 2, 5, 10 μM) to field samples in a eutrophic site (St. 1) and an oligotrophic site (St. 22) in 2010 as well as a eutrophic site (St. 1, 5), a mesotrophic site (St. 19), and an oligotrophic site (St. 22) in 2011 at Jinhae Bay, Korea. The phytoplankton growth in the areas with additional nitrates and phosphates on St. 1 were significantly different from the control (One-way ANOVA:P<0.01). The dominant species at St. 1 in 2010 were Heterocapsa triquetra and Pseudo-nitzchia spp., to which nitrate and phosphate were added, respectively. The dominant species at St. 22 in 2010 differed between treatment conditions as follows: nitrate treatment Chaetoceros spp. (≤ 10 μM), Thalassiosira spp. (20 μM), and Pseudo-nitzchia spp.(≥ 50 μM) for nitrate treatment; Cylindrotheca spp. (2 μM) and Pseudo-nitzchia spp. (5 μM) for phosphate treatment. Phytoplankton growth in 2011 according to the added nutrient were significantly different with treatment concentrations (One-way ANOVA: P<0.01). Moreover, the beginning of exponential growth in phytoplanktons was different between the eutro-mesotrophic sites (St. 1, 5, and 19) and the oligotrophic sites (St. 22) on day 2 and day 6 respectively. This implies that phytoplankton growth in the low nutrient condition may be retarded. The dominant species at St. 1 were Eucampia spp. and Chaetoceros spp. in the low nutrient treatment compared to Skeletonema spp., and Thalassiosira spp in the high nutrient treatment. The dominant species at St. 5 and St. 19 were mostly Skeletonema spp. and Chaetoceros spp. However, the dominant species at St. 22 was Thalassiosira spp.. The results of this study showed that phytoplankton growth and composition were different in areas with different nutrient characteristics resulting from the additional nutrients. Therefore, the nutrients additional algal assay could be indirectly explained why the biomass and composition of phytoplankton in Jinhae Bay has shown spatial differences.

춘계 진해만에서 식물플랑크톤 증식과 제한영양염 분포특성

손문호(Son, Moonho),김동선(Kim, Dong-Sun),백승호(Baek, Seung-Ho) 한국산학기술학회 2014 한국산학기술학회논문지 Vol.15 No.5

춘계 진해만에서 식물플랑크톤의 분포특성에 영향을 미치는 영양염 농도 및 거동을 파악하기 위해서 총 23개 정점에 서 2010과 2011년에 현장조사를 수행하였고,지리지형학 특성과 오염물 부하를 고려하여 4개의 구역으로 구분하여 평가하였 다.진해만 광역해역에서 해역별 영양염 제한은 해수 순환이 원활한 중앙해역인 구역 II에서 80% 이상으로 가장 높게,다음으 로 서남해역의 구역 III과 IV에서는 17%-83%의 중간정도로 나타났으며,마산만 인근의 반폐쇄적인 구역 I에서는 35%이하로 낮게 관찰되었다.연도별 영양염 공급원으로는 2010년에는 오·폐수 등에 의한 질소기원 영양염의 유입이 높은 비중을 차지하 였고,2011년에는 강우에 의한 담수유입에 의하여 해역의 저염분화와 더불어 질소,규소,인 계열의 영양염이 동시에 유입되 었다.특히 2010년에는 질소계열의 영양염과 규조류(Pseudo-nitzchiaspp.)의 높은 상관성을 보였고,2011년에는 모든 영양염 과 규조류 (Leptocylindrusdanicus)와 높은 관련성이 있었다.결과적으로 춘계 진해만에 유입되는 질소 계열의 영양염은 규 조류의 성장에 중요한 영향을 미쳤으며,그들의 빠른 영양염 섭취(uptake)로 인하여 해역에 따라서 영양염 절대농도 뿐 만 아니라,영양염 구성성분비의 제한을 일으킬 수 있다는 것을 파악하였다. We investigated to assess the relationships between the major nutrients and phytoplankton dynamics during the spring season in 2010 and 2011 at 23 stations in Jinhae Bay, Korea. The bay is divided into four different zones based on pollutant sources and geographical characteristics. Nutrient limitation (>80%) was significant in Zone II, which is located in central bay and is influenced by the water well mixed from outer bay. The limited nutrient was followed in Zone III and IV that was occupying between 17% and 83%. However, the low levels are being kept below 35% in Zone I, which is characterized by the semi-enclosed eutrophic area of Masan and Haegam bays. Based on the PCA (principle component analysis) analysis, the nitrogen (N) sources in 2010 were particularly dominant and it may be due to the water mixing and wastewater formed from bottom layers and sewage. In 2011, major nutrients including nitrogen, silicon and phosphorus were dominant in the bay and are supplied by the river discharge after rainfalls with low salinity conditions. In particular, the N nutrients being supplied in 2010 are correlated with pennate diatoms Pseudo-nitzchia spp. and is not related to the phytoplankton population densities in 2011. The present study suggests that N sources play an important role in the proliferation of diatom, and the rapid nutrient uptakes by them are potential nutrient limitation factors in the bay.

Effects of chemically enhanced water-accommodated fraction of Iranian heavy crude oil on periphytic microbial communities in microcosm experiment.

Baek, Seung Ho,Son, Moonho,Shim, Won Joon Springer Verlag 2013 Bulletin of environmental contamination and toxico Vol.90 No.5

<P>Exposure experiments were conducted to determine the effects of an oil spill on a periphytic microbial community with the chemically enhanced water-accommodated fraction (CEWAF) of Iranian Heavy Crude oil in a microcosm containing artificial benthic substrates. Bacteria and heterotrophic nano-flagellates (HNF) grew well in all the treatments, except for the 100% CEWAF exposure. However, periphyton did not adapt to concentrations of CEWAF 20%. Among the periphyton, Cylindrotheca spp. dominated under treatment conditions, and the response of Cylindrotheca spp. to CEWAF (i.e., particularly 10%) closely followed the changes in chlorophyll a concentration. The concentrations of petroleum hydrocarbons from 10% and 20% CEWAF seemed to have a negative effect on periphyton and a growth-promoting effect on bacteria and HNF, respectively.</P>

Enhanced species-specific chemical control of harmful and non-harmful algal bloom species by the thiazolidinedione derivative TD49

Baek, Seung Ho,Son, Moonho,Jung, Seung Won,Na, Dong Hee,Cho, Hoon,Yamaguchi, Mineo,Kim, Si Wouk,Kim, Young Ok Springer-Verlag 2014 Journal of applied phycology Vol.26 No.1

Temporal variation in the vertical distribution of microphytobenthos in intertidal flats of the Nakdong River estuary, Korea

Du, Guo Ying,Son, Moonho,An, Soonmo,Chung, Ik Kyo Elsevier 2010 Estuarine, coastal and shelf science Vol.86 No.1

<P><B>Abstract</B></P><P>The vertical distribution of microphytobenthos (MPB) was investigated in intertidal flats of the Nakdong River estuary over different temporal periods. The MPB biomass were measured as chlorophyll <I>a</I> concentration in the sediment, and monitored at two different depth scales. From August 2006 to August 2007, monthly sampling was carried out at four sites to a depth of 10cm. The vertical distribution exhibited an exponential decline with depth and the slope was closely related to sediment composition and MPB biomass in the surface sediment. The two slightly muddy sand (5–25% mud, <63μm) sites presented similar trends of seasonal variation to a sediment depth of 10cm, and no statistical difference was observed in their initial values and the slope of the exponential curves applied to each data set. The site with higher mud content also had higher surface biomass, and the fitted exponential curve had a larger slope than sites with more sand content. The seasonal variations of phaeo-pigments compared to chlorophyll <I>a</I> revealed higher grazing stress on the MPB in summer at the three slightly muddy sand sites, and low grazing stress all year around at the sand (<5% mud) site. In January, April and October 2007, and January 2008, diurnal sampling was conducted at hourly intervals at one slightly muddy sand site. The investigation in January 2007 which was conducted at 1cm intervals to a depth of 10cm sediment showed the migration mainly existed in the upper 1cm. The other diurnal sampling was undertaken to a 1cm depth at 0.5mm intervals. An evident migratory rhythm was present, with migration up to the surface during daytime emersion and down into deeper sediment during night and high tide submersion. Migrating cells could reach sediments as deep as 6 or even 10mm. When the visible thick biofilms formed, the migratory rhythm changed by keeping higher biomass at the surface even at night and during high tide submersion. Generally, the MPB surface biomass was an important factor in structuring the MPB vertical distribution. The vertical distribution to depths of 10cm was closely related to the sediment composition over the long term, while the MPB migration influenced the vertical distribution over the short term in the top 1cm of the sediment.</P>

춘계 진해만의 유독 와편모조류 Alexandrium 출현에 따른 동물플랑크톤의 마비성 패독의 변화 특성

리페이진(Peijin Li),손문호(Moonho Son),서민호(Min Ho Seo),한지승(Ji Seung Han),오석진(Seok Jin Oh) 한국해양환경·에너지학회 2023 한국해양환경·에너지학회 학술대회논문집 Vol.2023 No.05

Assessing the Ecosystem Health Status of Korea Gwangyang and Jinhae Bays based on a Planktonic Index of Biotic Integrity (P-IBI)

Baek, Seung Ho,Son, Moonho,Kim, Dongseon,Choi, Hyun-Woo,Kim, Young-Ok 한국해양학회 2014 Ocean science journal Vol.49 No.3

To assess the responses of planktonic organisms to pollutants in the coastal ecosystems of Gwangyang and Jinhae bays in Korea, we investigated seasonal changes in various biological factors during the period from 2010 to 2012. Based on the characteristics of nutrient uptake by planktonic organisms under the coastal pollution conditions, we focused on four major parameters: total phytoplankton, harmful algal bloom (HAB) species, heterotrophic bacteria (HB) and Escherichia coli to develop a planktonic index of biotic integrity (P-IBI). The threshold values for abundances of total phytoplankton, HAB species and HB were based on the zero Z-score following normal distribution of the data for each parameter during the three years. Based on this approach, the threshold values were: $1.2{\times}10^6\;cells\;L^{-1}$ for total phytoplankton; $3.3{\times}10^4\;cells\;L^{-1}$ for HAB species; and $1.7{\times}10^6\;cells\;mL^{-1}$ for HB. Five grade levels for the P-IBI were established, based on the zero Z-scores. The threshold value for E. coli not to be normalized was based on the USEPA and the Korean Ministry of Oceans and Fisheries guidelines. Validity of the grades and threshold values for each parameter established using the field data were tested by algal bioassays in a mesocosm enclosure, which supported the threshold values obtained in the field. In Gwangyang Bay, the annual integrated score for the P-IBI in 2010 was better than in the other years of the study. In Jinhae Bay, the P-IBI for the inner area of Masan Bay was Grade IV-V, indicating unhealthy conditions relative to the central and western outer areas, where the P-IBI varied from Grade II to III. The P-IBI values for Gwangyang and Jinhae bays were mostly rated as "Good (Grade II) or Fair (Grade III)", except for a few stations in the semi-enclosed areas of the inner part of Jinhae Bay. From an overall view based on the P-IBI developed in this study, the coastal ecosystem health status in Gwangyang Bay was in a better condition than Jinhae Bay. The P-IBI indicated also a change to an unhealthy status during the rainy periods of spring and summer, whereas during winter and autumn the index indicated healthy conditions.

장기저장성 평가를 통한 전기식 기폭관 K13의 설계수명예측

백승준(Seungjun Back),손영갑(Youngkap Son),박상현(Sanghyun Park),이문호(Moonho Lee),강인식(Insik Kang) 한국추진공학회 2018 한국추진공학회 학술대회논문집 Vol.2018 No.5