남해동부해역의 표층 수괴 변화에 따른 환경요인과 식물플랑크톤 군집의 계절적 변화

장풍국,현봉길,차형곤,정한식,장민철,신경순 한국해양과학기술원 2013 Ocean and Polar Research Vol.35 No.2

We investigated the seasonal succession of phytoplankton assemblages in the eastern part of the South Sea of Korea in relation to surface water masses. The study areas are under the direct influence of the Tsushima Warm Current (TCW) throughout the whole year, with its strength known to be seasonally variable. The region is also influenced by coastal waters (CW) driven from the South Sea of Korea and East China Sea, particularly in summer, as indicated by low salinity in the surface water. Nutrient property of the TCW can reveals whether the origin of the TCW is the nutrient-rich Kuroshio Current or the oligotropic Taiwan Warm Current. Surface chlorophyll-a (Chl-a) concentrations displayed a large seasonal variation for all stations, with high values found in spring and autumn and low values in summer and winter. At station M (offshore) and P (intermediate location between M and R), Chl-a concentrations in October were higher than those in March, when spring bloom normally occurs. This may be related to deeper mixed layer depths in October. Diatoms dominated under conditions of high nutrient supply in which Chaetoceros spp. and Skeletonema costatum-like spp. were abundant. S. costatum-like spp. dominated at stations R (onshore station) and P in December when there was greater nutrient supply, especially of phosphate. Flagellates and dinoflagellates dominated at all three stations after diatoms blooms. Dominant species were Scrippsiella trochoid in April and Ceratium furca in October at station R, and Gyrodinium spp. and Gymnodinium spp. at station M during summer, when the effect of the oligotropic Taiwan Warm Current and the oligotropic coastal water from East China Sea were strong. Redundancy analysis showed clear seasonal successions in the phytoplankton community and environmental conditions, in which both principal components 1 and 2 accounted for 69.6% of total variance. Our results suggested that environmental conditions seemed to be determined by the origin of the TCW and the relative seasonal strength of the water masses of the TCW and CW, which may affect phytoplankton growth and compositions in the study area.

쿠로시오가 우리나라 남해안에 미치는 영향에 대한 연구

장풍국,신경순,황옥명,장민철,이우진,현봉길 대한조선학회 2011 대한조선학회 학술대회자료집 Vol.2011 No.6

Long-term Changes of Disinfection Byproducts in Treatment of Simulated Ballast Water

장풍국,차형곤 한국해양과학기술원 2020 Ocean science journal Vol.55 No.2

This study investigated the changes in concentrations of haloacetic acids (HAAs) and haloacetonitriles (HANs) as disinfection byproducts (DBPs) for different storage times (as long as 20 days) and temperatures (5 to 20°C). A ship’s voyage after treatment of its ballast water with active substances was considered. The HAA showed a clear trend of increasing concentration only with storage time, especially for dibromoacetic acid (DBAA). Dissolved organic nitrogen concentration was increased by the decomposition of dead organisms at 10 days, and then reacted with the remaining total residual oxidants, resulting in increased concentration of DBPs. An environmental risk assessment indicated that DBAN and monochloroacetic acid (MCAA) could have a negative impact on the marine environment. This study suggests that, because all international vessels must have a ballast water management system installed by September, 2024, the concentrations of DBPs, especially DBAN, MCAA, and DBAA, should be monitored in the waters at major international ports.

우리나라 주요 국제항에 입항하는 중국 기원 선박의 평형수내 수질 및 식물플랑크톤 특성 연구

장풍국,현봉길,장민철,신경순,Jang, Pung-Guk,Hyun, Bonggil,Jang, Min-Chel,Shin, Kyoungsoon 해양환경안전학회 2016 해양환경안전학회지 Vol.22 No.7

본 연구는 우리나라 주요 국제항에 출입하는 중국기원 선박의 선박평형수내 환경 및 부유생물의 특성을 파악하여 선박평형수 처리장치(BWTS)와 관련된 면제 협상을 위한 기초자료를 확보하고자 하였다. 조사된 37척의 선박 중 평형수의 보관 기간은 발해만을 포함하는 북부지역(지역 "A")에서 평균 $3.91{\pm}4.61days$로 가장 짧았다. 총부유물질의 농도는 $1.80{\sim}266mg\;L^{-1}$의 범위를 보였고, 용존성 및 입자성 유기물질은 각각 $1.09{\sim}5.79mg\;L^{-1}$, $0.17{\sim}3.65mg\;L^{-1}$의 범위를 나타내었다. 영양염 농도는 양자강 유역을 포함한 지역 "B"에서 높았고, 홍콩을 포함하는 지역 "C"에서 낮은 평균값을 보였다. 엽록소-a 평균 농도는 $0.67{\pm}1.15{\mu}g\;L^{-1}$로 나타났고, $1{\mu}g\;L^{-1}$ 이상의 높은 값은 지리적으로 우리나라와 가까운 지역 "A"에서 7척 중 3척이 집중되었다. 식물플랑크톤의 개체수가 > $10,000cells\;L^{-1}$의 선박평형수는 37척 중 6척으로 나타났고, 이 중 3척이 지역 "A" 기원으로 파악되었다. 특히, 홍콩항에서는 유해미세조류로 잘 알려진 와편모그룹의 종이 높은 밀도로 관찰되었다. 본 연구 결과, 중국과의 BWTS 면제권 협상은 신중하게 접근할 필요성이 있다고 판단된다. The water quality and phytoplankton presence in the ballast water (BW) of 37 vessels originating from the international ports of China were investigated to facilitate negotiations for exemptions to the Ballast Water Management Convention (BWM Convention). The shortest duration given BW spent in a vessel was $3.91{\pm}4.61days$ in area "A", which included the Bohai Sea. Total suspended solids, dissolved organic carbon, and particulate organic carbon ranged from 1.80 to $266mg\;L^{-1}$, from 1.09 to $5.79mg\;L^{-1}$, and from 0.17 to $3.65mg\;L^{-1}$, respectively. A low average concentration of nutrients was measured in BW from area "C", but the concentration of nutrients in BW from area "B" (around the Changjiang estuary) was high, which may be related to the relevant supply of freshwater. A high chlorophyll-a concentration (> $1{\mu}g\;L^{-1}$) was measured in six vessels, three of which carried BW in the area "A". High abundance of phytoplankton (> $10,000cells\;L^{-1}$) was measured in four vessels, two of which carried BW in the area "C". Vessel No. 37, originating from Hong Kong Bay in area "C", showed a high density of dinoflagellates. The results suggest that BWM Convention exemption negotiations with China should be performed cautiously.

광양만에서 무기 영양염의 시공간적 분포를 조절하는 요인

장풍국,이재도,장만,신경순,이원제,장민철,이우진,황근춘 한국해양과학기술원 2005 Ocean and Polar Research Vol.27 No.4

In order to understand the spatial and temporal variations of nutrients and factors controlling their distribution in Gwangyang Bay, this study was carried out bimonthly from June 2001 to July 2003. Inorganic silicate and nitrate concentrations ranged from 0.04mM to 69.5mM (avg. 12.9 mM), and from 0.12 mM to 42.2 mM (avg. 7.83 mM), respectively. Silicate concentrations measured just after the typhoon were the highest with an average of 43.2 mM at the surface layer in June 2001, whereas the highest nitrate concentration (avg. 37.0 mM) was observed in the surface layer in July 2003. River runoff apparently influenced variations in silicate and nitrate concentrations (r=0.701 and 0.728, p<0.000, respectively) as well as salinity (r = -0.628, p<0.000). Phosphate concentrations ranged from 0.24 mM to 5.70 mM (avg. 1.34mM) and were highest at stations 5, 6, and 7, near a fertilizer plant with an average of 2.01 mM. On the basis of N/P and Si/N molar ratios, limiting nutrients have varied temporary and spatially. During 2001-2002, nitrogen was a limiting nutrient in the study area, and phosphate was limited when a large volume of freshwater flowed into the bay. Silicate was limited when the high standing crops of phytoplankton occurred in the whole study area throughout 2003, and in the inner bay in February and August 2002. During the study period, factors controlling the distribution of nutrients might be summarized as follows; 1) inflow of freshwater by heavy rain accompanied by typhoons and frequent rainfall in summer, showing high concentrations of silicate and nitrate, 2) release of high phosphate concentrations from the fertilizer plant located in the south of Moydo to adjacent stations, 3) release of nutrients from bottom sediment, 4) magnitude of occurrence of phytoplankton standing crops.

Study on the Distribution of Surface Chlorophyll-a and Subsurface Chlorophyll Maximum in the Southeastern Yellow Sea According to the Typhoon Paths and Water Masses

장풍국,강정훈,신경순 한국해양과학기술원 2020 Ocean science journal Vol.55 No.3

The influences of physiochemical processes on the distribution of surface chlorophyll-a(Chl-a) and subsurface chlorophyll maximum (SCM) were investigated in the southeastern Yellow Sea (YS) during summer in 2010-2013. The paths of typhoons from 2010 to 2012 were different, resulting in different patterns of surface Chl-aand the SCM layer. Surface Chl-aappeared in high concentrations at the coastal area in 2010 and 2012, and at all stations in 2011. The SCM layer descended in the central area in 2012 and rose in the coastal area in 2010, and lifted at all stations in 2011. The SCM layer was shallower from the open sea located at the Yellow Sea Cold Water to the coastal area due to tidal fronts and topographic properties. As a result, the distribution characteristics of Chl-aconcentration according to typhoon paths and water masses may affect the marine ecosystem in the YS.

선박평형수 처리에 있어 활성물질 농도와 식물플랑크톤 개체수가 소독부산물생성에 미치는 영향

장풍국,현봉길,차형곤,신경순 해양환경안전학회 2017 해양환경안전학회 학술발표대회 논문집 Vol.2017 No.04

선체부착생물 관리에 대한 국제적인 동향 및 국내 위해성 평가에 대한 소개

장풍국,현봉길,신경순,서진영,장민철 한국해양환경·에너지학회 2023 한국해양환경·에너지학회지 Vol.26 No.3

The International Maritime Organization (IMO) continues to discuss ship’s ballast water and biofouling to ninimize the transfer of invasive aquatic species from entering the port. Since the entry into force of the international convention, ballast water has been legally required to be discharged in accordance with the emission permit standard by installing a ballast water management system approved by the government on international ships since 2019. The Biofouling Guidelines for management of hull-attached organisms are being actively discussed in subcommittees of the IMO Marine Environmental Protection Committee. Currently, the draft of 2023 Biofouling Guideline, which revised the existing guidelines (2011 Biofouling Guideline), has requested approval from the 80th MEPC, and guidance related to in-water cleaning for the management of biofouling will be set the target completion year of the output to 2025. Considering this, it is expected that legal regulations will be implemented after 2025 by developing Biofouling Management Convention and In-water Cleaning Guidance. New Zealand has enacted its own law on biofouling and has been implementing it as compulsory regulations since May 2018, and Australia will also manage bio-fouling as compulsory regulations from December 2023. To establish a management system to protect the ecosystem of domestic ports from invasive aquatic species entering international ports by biofouling, the government is supporting research projects to legislate on biofouling management, support the domes-tic industry for in-water cleaning, and respond to the biofouling policy of the IMO.

선박평형수 처리시스템의 식물플랑크톤 사멸여부에 대한 디지털 형광현미경 적용 연구

장풍국 해양환경안전학회 2016 해양환경안전학회 학술발표대회 논문집 Vol.2016 No.11

장목만에서 여름철 영양염 특성 변화가 식물플랑크톤 군집구조에 미치는 영향

장풍국,이우진,장민철,신경순 한국해양과학기술원 2010 Ocean and Polar Research Vol.32 No.2

Phytoplankton production is affected by various physico-chemical factors of environment. However, one of the most critical factors generally accepted as controlling primary production of phytoplankton is nutrients. It has recently been found that the succession of phytoplankton groups and species are closely related to the chemical properties of ambient water including nutrient limitation and their ratios. In Jangmok Bay, silicate and nitrate are primarily supplied by rainfall, while phosphate and ammonia are supplied by wind stress. Typhoons are associated with rainfall and strong wind stress, and when typhoons pass through the South Sea, such events may induce phytoplankton blooms. When nutrients were supplied by heavy rainfalls during the rainy season and by summer typhoons in Jangmok Bay, the dominant taxa among the phytoplankton groups were found to change successively with time. The dominant taxon was changed from diatoms to flagellates immediately after the episodic seasonal events, but returned to diatoms within 3~10 days. Pseudo-nitzschia spp. were dominant mainly in the presence of low phosphate levels during the first of the survey which included the rainy season, while Skeletonema costatum was dominant when phosphate concentrations were high due to the strong wind stress during the latter half of the survey as a result of the typhoon. The competition between S. costatum and Chaetoceros spp. appeared to be regulated by the silicate concentration. S. costatum preferred high silicate and phosphate concentrations; however, Chaetoceros spp. were able to endure low silicate concentrations. These results implied that, in coastal ecosystems, the input patterns of each nutrient supplied by rainfall and/or wind stress appeared to contribute to the summer succession of phytoplankton groups and species.