• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.400-401
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• 2000

국내에서 적조연구는 국립수산진흥원에서 남해를 비롯 우리나라 연안의 모니터링과 한양대학교 연구팀의 마산만에 관한 연구가 초기부터 활발하게 이루어졌다. 적조 연구는 주로 적조원인 플랑크톤의 발생규모, 계절적 변동과 그 때 수질환경을 조사하였고 대체로 군집 수준에서 다루어졌다 (박과 김, 1967; 유와 이, 1976; Yoo and Lee, 1979; 박, 1982). 우리나라의 적조 연구는 주로 마산-진해만애서 이루어져 왔다. 마산만과 진해만을 비롯 행암만, 덕동만, 진동만, 칠천수로 등이 그 대상지가 되었으며 이 지역에서는 그동안 상당한 자료가 축적되어 왔다. 하지만 본 연구 대상지역인 광양만에서 적조연구에 관한 자료가 미흡하여 본 연구는 기존의 적조생물의 군집 수준의 연구와 유사하다. 개체군의 변동을 파악하는데 중점을 두었고 광양제철소를 중심으로 하여 남해 일대에 걸쳐 모니터링을 하고 수환경의 특성과 개체군 변동을 동시에 조사함으로서 제철소 건립 후 광양만에서 적조 발생의 최근적조 양상을 분석하였다. (중략)

• Proceedings of the KIPE Conference
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• 2003.07b
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• pp.938-941
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• 2003

본 시스템은 나주 생물자원산업화센터에 설치된 태양광 및 태양열 시스템에 대한 운전결과특성으로써 특용작물배양의 전원 및 온수공급을 위한 것이다 태양광발전은 10kWP이고, 태양열시스템은 500l 로 구성되어 있다. 태양광발전시스템의 인버터는 10kW급 계통연계형으로써 상용전원과 연계해서 사용할 수 있도록 하였으며 태양열시스템은 생물자원산업화센터의 실험용 급탕으로 사용된다. 본 논문에서는 태양광발전과 태양열시스템이 설치된 생물자원산업화센터에 상주 근무인원을 대체하기 위해서 원격 모니터링 시스템을 구성하였고, 모니터링에 의해 축적된 데이터를 통해 그 특성을 비교하고자 한다.

• Korean Journal of Environmental Biology
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• v.20 no.2
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• pp.118-129
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• 2002

Zooplankton was sampled vertically with a Norpac net from Gamag Bay in April, July, September and December, 2001. Copepods were predominant in April and December, and cladocerans in July and Noctituca scintillans in September, respectively. There are high spatio-temporal fluctuations in the abundance of zooplankton with a range of 22-17,197 indiv.$m^3$. In the copepod community, neritic species, Eurytemora pacifica, Acartia omorii, Centropages abdominalis and Calanus sinicus were predominant in April ; Labidocera rotunda and A. erythraea in July; A. erythraea and Paracalanus parvus s. 1. in September; A. omorii and E. pacifica in December. However, oceanic species Eucalanus sp. and Neocalanus sp. were abundant in September. It indicates that although Gamag Bay is semi-closed, the distribution pattern of zooplankton is seasonally strongly affected by oceanic waters in addition to neritic ones.

• Journal of Wetlands Research
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• v.17 no.3
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• pp.311-319
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• 2015

The Korean government has made progress in its project for sewage distribution in rural areas to ensure the balanced development of the country and its water conservation system. The project for sewage distribution in rural areas was analyzed with the yearly operational results of municipal wastewater treatment plant (MWTP). The sewage characteristics of the MWTP in a rural area changed according to seasonal variations, and the lowest pollution concentrations were obtained in the summer. The treatment efficiency of nutrients in the biological treatment process changed slightly more than the treatment efficiency of organic compounds, and the lowest treatment efficiency was obtained in winter. In addition, the relationship between treatment efficiency and retention time and F/M ratio showed similar results despite seasonal variations. It was considered that sewage characteristics and treatment efficiency changed according to seasonal variations when the treatment process was selected in MWTPs in rural areas. Especially, Maintenance of MWPT is need for the stable treatment efficiency of nutrients in the winter.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.444-445
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• 2000

계절, 서식 환경의 구분없이 발병하는 병원성 미생물로 인하여 어류의 감염피해 및 경제적 손실이 막대하며 병원성 미생물을 저해하기 위해 투여한 항생제의 오남용으로 인하여 내성을 갖는 세균들의 출현 위험성이 상재하고 있다. 따라서 항생제 사용에 대한 효과 감소는 물론 과량 투여에 따른 양식업의 경쟁력 약화로 이루어질 가능성이 높기 때문에 보다 환경 친화적이며 어병의 효율적인 생물학적 제어를 시도하기 위해 어류의 gastrointestinal(GI) track으로부터 수산용 probiotic 유산균을 분리 동정하고 그 특성을 조사하여 앞으로 수산용 probiotic으로서 이용가능성을 알아보고자 하였다. (중략)

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.647-658
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• 2018

The aim of this study is to investigate the seasonal changes of phytoplankton communities based on the environmental changes in a dense oyster farming area (Hansan-Geoje Island) from June to December 2016. The water temperature varied from $14^{\circ}C$ to $28.8^{\circ}C$ and its salinity ranged from 29.4 to 34.2 psu. Nitrate+nitrite was kept at c.a. $3.0{\mu}M$ on the surface layer from June to July, below the concentration limit in August and early September, and then gradually increased from late September. Ammonia was high on July 20 and August 10, and its seasonal characteristics were not clear. Phosphate ranged from 0.01 to $0.7{\mu}M$ on the surface layer, and its seasonal changes were similar to those of nitrate+nitrite. Mean silicate concentrations were $10.7{\mu}M$ on the surface and $15.7{\mu}M$ in the bottom layer, and it was not acted as a limiting factor for the growth of phytoplankton. Among the phytoplankton community, Bacillariophyceae, Dinophyceae and Cryptophyceae was 61.2%, 22.5%, and 13.6%, respectively. In late June, dinoflagellate Prorocentrum donghaiense was dominant in the outer waters(St. T1), later on, Cryptomonas spp. and Chaetoceros spp. were dominant, respectively. From late September to October, diatoms Pseudo-nitzschia spp. and Chaetoceros spp. were stimulated under non-stratified condition after the typhoon. In December, A. sanguinea was found to be $1.7{\times}10^5cells\;L^{-1}$. Seasonally, relative high phytoplankton biomass may be favorable to maintain high production of filter feeder oyster in the dense oyster farming areas of Hansan and Geoje Island.

• Korean Journal of Environmental Biology
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• v.38 no.1
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• pp.47-60
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• 2020

To assess the characteristics of phytoplankton community structures related to environmental factors, seasonal surveys were conducted in the vicinity of Dokdo. In 2019, phytoplankton of four phyla and 69 species were observed. During winter, unidentified nanoflagellates dominated, with an average of 3.19×10⁴ cells L^-1. In spring, unidentified nanoflagellates occupied about 50% of the composition and a variety of dinoflagellates appeared. The summer phytoplankton population showed very low abundance. In autumn, various species of Chaetoceros appeared, along with diatoms, such as Bacteriastrum spp., Guinardia striata, and Pseudo-nitzschia spp. In addition, tropical species Amphisolenia sp. and Ornithocercus sp. were observed in both 2018 and 2019. The diversity was high in the summer of 2018 and the winter of 2019 and the characteristics of each index varied. Cluster analysis was divided into four groups according to species and population characteristics regardless of the season. The stratification of spring was particularly weak. In the autumn of 2018, the water mass was stabilized in the same way as in the summer, which is considered a suitable condition for phytoplankton growth. However, in 2019, the water masses were mixed, resulting in a low population. In a phytoplankton comparison, the dominant group showed seasonal differences, except for summer when the population was low, and the difference was most pronounced in autumn. Therefore, the waters surrounding Dokdo have different environmental and ecological characteristics from the East Sea, but the seasonal characteristics of each year are considered to be different depending on the topography, various currents, the island effect, and other factors.

• Korean Journal of Environmental Biology
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• v.40 no.1
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• pp.70-86
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• 2022

A survey was conducted to analyze seasonal dynamics of the phytoplankton community at 22 stations on the surface and bottom layers in the Anma Islands of Yeonggwang(AIY) in the southern West Sea, Korea from the spring of 2020 to the winter of 2021, using a marine survey vessel Ed Ocean. Based on the survey results, there were 87 phytoplankton species in 52 genera, diatoms accounted for 67.8%, dinoflagellates 26.5%, silicoflagellates 3.5%, and cryptomonads and euglenoids accounted for 1.1% each. By season, it was simple in spring and relatively varied in winter. The phytoplankton standing crop on the surface was low (28.8±30.1 cells mL^-1) in summer and high (87.0±65.1 cells mL^-1) in spring. In the phytoplankton community, diatoms showed a high share (over 80%) throughout the year, and Skeletonema costatum-ls was the dominant species with a dominance of more than 60% in spring and winter, and 34.6% and 24.2% in summer and autumn, respectively. The diversity expressing the characteristics of the community structure was high (2.79±0.45) in autumn and low (1.82±0.18) in spring, unlike the phytoplankton standing crop. However, the dominance was high at (0.86±0.08) in spring and low (0.44j0.13) in autumn. Based on the results of principal component analysis (PCA) using environmental and phytoplankton-related factors, it was estimated that the biological oceanographic environmental characteristics seen through the phytoplankton community in the AIY were dominated by nutrients supplied from open seawater and surface sediments by seawater mixing, such as tidal mixing.

• Proceedings of the KSRS Conference
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• 2007.03a
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• pp.49-54
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• 2007

고분해능복사계(AVHRR) 자료로부터 산출한 아시아지역 지면피복 분류자료들 (United States Geological Survey: USGS, International Geosphere Biosphere Programme: IGBP, University of Maryland: UMd)의 분류특성을 분석하였으며 이를 근거로 하여 이 지역에 대한 지면피복의 분류를 시도하였다. 서로 다른 지면피복 분류 자료들의 비교를 위하여 지도 투영법을 일치시켰으며 지면피복 정의가 유사한 유형들만 비교하였다. 세 지면피복 자료에서 분류가 모두 일치하는 비율은 33.57%이고 3 자료 중 두 자료에서 분류가 일치하는 비율은 49.69%로 나타났다. 전체적으로 나대지(사막)， 도시 및 혼합림과 같이 식생의 생물리적 특성이 뚜렷한 유형들에서는 분류의 일치율이 높게 나타났다. 반면에 농지， 낙엽활엽수림， 및 낙엽침엽수렴과 같이 식생의 생물리적 특성이 유사한 유형에서는 일치율이 낮게 나타났다. 분류에 사용된 기본 입력자료수， 지면피복 유형수，분류기법 및 입력 자료의 전처리 수준 등이 지면피복 분류 결과에 차이를 유발한 것으로 판단된다. 지면피복 자료들의 비교결과와 각 유형별 식생지수의 평균 계절변동 특성을 이용하여 이 지역에 대한 지면피복 분류자료를 보완하였다.

• Korean Journal of Ichthyology
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• v.26 no.4
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• pp.303-309
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• 2014

Feeding ecology of Collichthys lucidus was determined by analysis of stomach contents of 926 specimens ranged from 3.5 to 18.5 cm in the Han River estuary. This fish actively fed on benthic crustaceans, mainly decapods, Palaemon carinicauda and Acetes chinensis, and they can be defined as the benthivorous predator. The percentage of empty stomachs was 23.8%. The vacuity index (VI) did not vary with the size classes, but showed significant monthly variations. Monthly variation of feeding activity appears to be related to the reproduction cycle of the fish, and to the temporal abundance of the prey organisms. Collichthys lucidus in Han River estuary fed on a wide array of prey items and could be considered as a non-selective predator.