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Environmental Pollutants in Streams of Andong District and Insect Immune Biomarker (안동지역 하천의 환경오염물질과 곤충면역 생체지표 분석)

  • Ryoo Keon Sang;Ko Seong-Oon;Cho Sunghwan;Lee Hwasung;Kim Yonggyun
    • Korean journal of applied entomology
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    • v.44 no.2
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    • pp.97-108
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    • 2005
  • Samples of water, soil, and sediment were taken from 10 streams near Andong, Korea in May 2004. To assess the degree of environmental pollution of each stream, chemical pollutants such as total notrogen (T-N), total phosphorus (T-P), chemical oxygen demand (COD), heavy metals, organophosphorus pesticides, organochlorine pesticides, and dioxin-like PCB congeners were analyzed by standard process tests or U.S. EPA methods. In addition, biomarkers originated from insect immune systems of beet armyworm, Spodoptera exigua, were used to analysis of the environmental samples. Except Waya-chun stream showing T-N content of 9.12 mg/L, most streams were contaminated with relatively low levels of overall pollutants in terms of T-N, T-P, and COD, compared to their acceptable environmental levels designated by the Ministry of Environment. Contents of Pb and Cd in samples of each stream were much lower than environmentally permissible levels. However, several times higherconcentrations of Pb and Cd were found in locations at Mi-chun, Kilan-chun, and Hyunha-chun streams, in comparison with other streams. Diazinon, parathion, and phenthoate compounds among organophosphorus pesticides were detected as concentrations of 0.19, 0.40, and $1.13\;{\mu}g/g$, respectively, from soil sample collected in the vicinity of Mi-chun stream. On the other hand, 16 organochlorine pesticides and 12 dioxin-like PCB congeners, known as endocrine disrupting chemicals, selected in this study were not found above the limit of detection. Biomarker analyses using insect immune responses indicated that Waya-chun stream was suspected as exposure to environmental pollutants. Limitation and compensation of both environmental analysis techniques are discussed.

Estimation of Ground-level PM10 and PM2.5 Concentrations Using Boosting-based Machine Learning from Satellite and Numerical Weather Prediction Data (부스팅 기반 기계학습기법을 이용한 지상 미세먼지 농도 산출)

  • Park, Seohui;Kim, Miae;Im, Jungho
    • Korean Journal of Remote Sensing
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    • v.37 no.2
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    • pp.321-335
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    • 2021
  • Particulate matter (PM10 and PM2.5 with a diameter less than 10 and 2.5 ㎛, respectively) can be absorbed by the human body and adversely affect human health. Although most of the PM monitoring are based on ground-based observations, they are limited to point-based measurement sites, which leads to uncertainty in PM estimation for regions without observation sites. It is possible to overcome their spatial limitation by using satellite data. In this study, we developed machine learning-based retrieval algorithm for ground-level PM10 and PM2.5 concentrations using aerosol parameters from Geostationary Ocean Color Imager (GOCI) satellite and various meteorological parameters from a numerical weather prediction model during January to December of 2019. Gradient Boosted Regression Trees (GBRT) and Light Gradient Boosting Machine (LightGBM) were used to estimate PM concentrations. The model performances were examined for two types of feature sets-all input parameters (Feature set 1) and a subset of input parameters without meteorological and land-cover parameters (Feature set 2). Both models showed higher accuracy (about 10 % higher in R2) by using the Feature set 1 than the Feature set 2. The GBRT model using Feature set 1 was chosen as the final model for further analysis(PM10: R2 = 0.82, nRMSE = 34.9 %, PM2.5: R2 = 0.75, nRMSE = 35.6 %). The spatial distribution of the seasonal and annual-averaged PM concentrations was similar with in-situ observations, except for the northeastern part of China with bright surface reflectance. Their spatial distribution and seasonal changes were well matched with in-situ measurements.

Study on ${\ulcorner}Bonchojeonghwa{\lrcorner}$ ${\ulcorner}Inbu{\lrcorner}$ ("본초정화(本草精華)" "인부(人部)"에 대한 고찰)

  • Kwon, Young-Bae;Eom, Dong-Myung;Kim, Hong-Kyoon
    • Korean Journal of Oriental Medicine
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    • v.11 no.2
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    • pp.1-22
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    • 2005
  • Study on ${\ulcorner}$Bonchojeonghwa${\lrcorner}$, which is one of the most specialized medical books in Boncho(Herbal Medicines), has been done by comparing it with some other medical books published in the Chosun dynasty. Though there was not meaningful result on e names of Korean medicine by this study and more study should follow in the future, from medicines recorded in ${\ulcorner}$Inbu (a chapter of medical ingredients from human body)${\lrcorner}$, we can reach on some results as follows by comparing in names of Korean medicines, their medical components, relevant explanations and etc. 1. Though it is difficult to know the author and the published year due to absence of the preface and epilogue, the publication is presumed to date from mid-l7th century, from the facts that Muheeong's ${\ulcorner}$Shinnongbonchokyongso${\lrcorner}$ is in the ${\ulcorner}$Bonchojeonghwa${\lrcorner}$'s reference list, and that there is not Hangul expression in the names of medicines nor the Ching dynasty’s books as a reference. 2. As a result of studying on the names of medicines recorded in ${\ulcorner}$Inbu${\lrcorner}$ of the Chosun dynasty's famous medical books, before ${\ulcorner}$ Bonchojeonghwa${\lrcorner}$, 19 medicines in ${\ulcorner}$Hyangyakjipsungbang${\lrcorner}$, 25 in ${\ulcorner}$Donguibogam${\lrcorner}$, and after ${\ulcorner}$Bonchojeonghwa${\lrcorner}$, 6 in ${\ulcorner}$Uimumbogam${\lrcorner}$, 4 in ${\ulcorner}$Kwangjebikup${\lrcorner}$, 11 in ${\ulcorner}$Bangyakhappyon${\lrcorner}$. And there are 37 medicines which are unique, ${\ulcorner}$Bonchojeonghwa${\lrcorner}$ has 31, the biggest records among them. 3. As a result of studying on the names of medicines recorded in 「Inbu」 of the ${\ulcorner}$Bonchojeonghwa${\lrcorner}$ and ${\ulcorner}$ Donguibogam${\lrcorner}$, 22 medicines were recorded in the both books, 9 were only recorded in ${\ulcorner}$Bonchojeonghwa${\lrcorner}$ and 3 were only recorded in ${\ulcorner}$Donguibogam${\lrcorner}$. 3 out of the total 37 medicines recorded in ${\ulcorner}$Inbu${\lrcorner}$ are only recorded in ${\ulcorner}$Hangyakjipsungbang${\lrcorner}$, and more study on this is needed. 4. From the contents recorded in ${\ulcorner}$Bonchojeonghwa${\lrcorner}$ and ${\ulcorner}$Donguibogam${\lrcorner}$, Benchojeonghwa is more in detail than Donguibogam. Thus, it was specialized in Boncho (Herbal Medicines) enough to be compared with general medical books, and played a good role in leading medical science's specialization. 5. Late Chosun dynasty's medical study on Boncho (Herbal Medicines) just like ${\ulcorner}$Bonchojeonghwa${\lrcorner}$ didn't lead to an active development of knowledge communication due to Confucian ethics. This limitation created the trend relying on general medical books or Yaksungga (songs of memorizing Boncho information) for Boncho information, but Boncho information of late Chosun dynasty became more in detail. That is, while Bokhapbang, combination of various medicines, were developed in China, Danmibang, single medicine but different intensity, were developed in Chosun. And thus, even though the kinds of medicines became smaller, but its contents became rather rich. 5. The medicines recorded in ${\ulcorner}$Bonchojeonghwa${\lrcorner}$ and ${\ulcorner}$Donguibogam${\lrcorner}$ are, from the view point of today, unclean or rather uncomfortable to use. Out those medicines, Bunchung, Hwasijangsanginkol, Hongyon, Gonidoogun, Inkondang had been used for a very long time and which proves their medical efficacy, and it is a great pity that they can’t be tried today due to the limitation by modern ethics.

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Analysis of the Geological Structure of the Hwasan Caldera Using Potential Data (포텐셜 자료해석을 통한 화산칼데라 구조 해석)

  • Park, Gye-Soon;Yoo, Hee-Young;Yang, Jun-Mo;Lee, Heui-Soon;Kwon, Byung-Doo;Eom, Joo-Young;Kim, Dong-O;Park, Chan-Hong
    • Journal of the Korean earth science society
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    • v.29 no.1
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    • pp.1-12
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    • 2008
  • A geophysical mapping was performed for Hwasan caldera which is located in Euisung Sub-basin of the southeastern part of the Korean Peninsula. In order to overcome the limitation of the previous studies, remote sensing technic was used and dense potential data were obtained and analyzed. First, we analyzed geological lineament for target area using geological map, digital elevation model (DEM) data and satellite imagery. The results were greatly consistent with the previous studies, and showed that N-S and NW-SE direction are the most dominant one in target area. Second, based on the lineament analysis, highly dense gravity data were acquired in Euisung Sub-basin and an integrated interpretation considering air-born magnetic data was made to investigate the regional structure of the target area. The results of power spectrum analysis for the acquired potential data revealed that the subsurface of Euisung Sub-basin have two density discontinuities at about 1 km and 3-5 km depth. A 1 km depth discontinuity is thought as the depth of pyroclastic sedimentary rocks or igneous rocks which were intruded at the ring vent of Hwasan caldera, while a 3-5 km depth discontinuity seems to be associated with the depth of the basin basement. In addition, three-dimensional gravity inversion for the total area of Euisung Sub-basin was carried out, and the inversion results indicated two followings; 1) Cretaceous Palgongsan granite and Bulguksa intrusion rocks, which are located in southeastern part and northeastern part of Euisung Sub-basin, show two major low density anomalies, 2) pyroclastic rocks around Hwasan caldera also have lower density when compared with those of neighborhood regions and are extended to 1.5 km depth. However, a poor vertical resolution of potential survey makes it difficult to accurately delineate the detailed structure caldera which has a vertically developed characteristic in general. To overcome this limitation, integrated analysis was carried out using the magnetotelluric data on the corresponding area with potential data and we could obtain more reasonable geologic structure.

Long-term (2002~2017) Eutropication Characteristics, Empirical Model Analysis in Hapcheon Reservoir, and the Spatio-temporal Variabilities Depending on the Intensity of the Monsoon (합천호의 장기간 (2002~2017) 부영양화 특성, 경험적 모델 분석 및 몬순강도에 따른 시공간적 이화학적 수질 변이)

  • Kang, Yu-Jin;Lee, Sang- Jae;An, Kwang-Guk
    • Korean Journal of Environment and Ecology
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    • v.33 no.5
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    • pp.605-619
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    • 2019
  • The objective of this study was to analyze eutrophication characteristics, empirical model analysis, and variation of water quality according to monsoon intensity in Hapcheon Reservoir for 16 years from 2002 to 2017. Long-term annual water quality analysis showed that Hapcheon Reservoir was in a meso-nutrition to eutrophic condition, and the eutrophic state intensified after the summer monsoon. Annual rainfall volume (high vs. low rainfall) and the seasonal intensity in each year were the key factors that regulate the long-term water quality variation provided that there is no significant change of the point- and non-point source in the watershed. Dry years and wet years showed significant differences in the concentrations of TP, TN, BOD, and conductivity, indicating that precipitation had the most direct influence on nutrients and organic matter dynamics. Nutrient indicators (TP, TN), organic pollution indicators (BOD, COD), total suspended solids, and chlorophyll-a (Chl-a), which was an estimator of primary productivity, had significant positive relations (p<0.05) with precipitation. The Chl-a concentration, which is an indicator of green algae, was highly correlated with TP, TN, and BOD, which differed from other lakes that showed the lower Chl-a concentration when nutrients increased excessively. Empirical model analysis of log-transformed TN, TP, and Chl-a indicated that the Chl-a concentration was linearly regulated by phosphorus concentration, but not by nitrogen concentration. Spatial regression analysis of the riverine, transition, and lacustrine zones of $log_{10}TN$, $log_{10}TP$, and $log_{10}CHL$ showed that TN and Chl-a had significant relations (p<0.005) while TN and Chl-a had p > 0.05, indicating that phosphorus had a key role in the algal growth. Moreover, the higher correlation of both $log_{10}TP$ and $log_{10}TN$ to $log_{10}CHL$ in the riverine zone than the lacustrine zone indicated that there was little impact of inorganic suspended solids on the light limitation in the riverine zone.

The study of Intercostal Nerve Block and Patient-Controlled Analgesia for Post-Thoracotomy Pain (개흉술 후 동통억제에 대한 신경차단법 및 환자자가 치료법의 비교연구)

  • 김우종;이길노
    • Journal of Chest Surgery
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    • v.30 no.9
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    • pp.920-926
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    • 1997
  • Remarkable effect of pain relief and prevention of the postoperative Complications after thoracotomy has been achieved by continuous intravenous analgesia. This study was carried out with thirty patients who underwent posterolateral thoraco tony. The patients were divided into three groups: Group I(n= 10), the patients with intermittent intramuscular analgesia(piroxicam 20 mg), Group II(n=10), the patients with continuous epidural analgesia(0.5% bupivacaine 30m1 + normal saline 30 ml + morphine 10 mg), and Group III(n= 10) the patients with controlled intravenous infusion of analgesics(fentanyl 2500 mfg +normal saline 10 ml). The results w re as follows; 1) There were no significant changes of vital signs, between groups. 2) Tidal volume and FVC were significantly improved in the group II and III compared with the group I during the first postoperative day. 3) A significant reduction of immediate post-thoracotomy pain was achieved in the group II and III compared with the group I. 4) The limitation of motion in the operative side was less in the group II and III compared with the group I. 5) A signi(icant reduction of the postoperative analgegics consumption was noticed in group II and III. 6) Significant complications were not occured during follow-up period in all groups.

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The Impact of Delayed Interval Delivery on Neonatal Mortality and Morbidity (지연 분만이 신생아의 사망률과 이환율에 미치는 영향)

  • Lee, Eun-Hee;Sohn, Jin-A;Lee, Ju-Young;Choi, Eun-Jin;Lee, Jin-A;Choi, Chang-Won;Kim, Ee-Kyung;Kim, Han-Suk;Jun, Jong-Kwan;Kim, Byeong-Il;Choi, Jung-Hwan
    • Neonatal Medicine
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    • v.18 no.1
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    • pp.111-116
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    • 2011
  • Purpose: To evaluate the impact of delayed interval delivery on neonatal outcomes. Methods: This was a retrospective study of infants who were born at Seoul National University Hospital by delayed interval delivery from June 2005 to July 2010. Outcomes (neonatal mortality and morbidity) of later babies were compared to those of the first babies and the control group whose gestational ages and birth weights were similar to them. Results: There were 4 twin and 5 triplet pregnancies. The first babies (group 1, n=9) were delivered at $22^{+6}$ to $27^{+5}$ weeks of gestational age, and the later babies (group 2, n=14) were born at $24^{+6}$ to $28^{+0}$ weeks. The mean interval between the first and later deliveries was 10 days, and there was no delay between the second and third deliveries in all triplet pregnancies. There were more small for gestational age (SGA) infants in group 1 than group 2 (66.7% and 21.4% respectively, P=0.03). Two of three babies who died in group 1 were born before 24 weeks of gestational age and expired within a week after birth. The mortality rate of group 2 (7.1%) was lower than group 1 (33.3%), but not significantly (P=0.106). The control group matched to group 2 consisted of 28 infants. There were no significant differences in neonatal mortality and morbidity between the two groups. Conclusion: Although there is a limitation to the number of infants in this study, it suggested that delayed delivery in a multiple pregnancy could decrease the incidence of SGA of the remaining fetuses and that prolonged gestation would not be harmful to those fetuses after birth.

Ventilator-Associated Pneumonia in Neonatal Intensive Care Unit : Clinical Manifestations, Ddiagnostic Availability of Endotracheal Tip Culture (신생아 집중치료실에서 인공 환기요법 관련 폐렴의 임상양상과 기관내 삽관의 유용성에 관한 연구)

  • Kim, Nam Young;Sung, Tae Jung;Shin, Seon Hee;Kim, Sung Koo;Lee, Kon Hee;Yoon, Hae Sun
    • Pediatric Infection and Vaccine
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    • v.12 no.1
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    • pp.67-74
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    • 2005
  • Purpose : The incidence of mortality associated with respiratory difficulties is decreasing nowadays contributed to the development of neonatology. However, complications associated with mechanical ventilator are increasing. This study is to determine clinical manifestations, diagnositc availability of the endotracheal tip culture in patients with Ventilator-Associated Pneumonia(VAP) in neonatal intensive care unit(NICU). Methods : A retrospective analysis of 50 neonates who were admitted to the NICU of Kangnam Sacred Heart Hospital and had given mechanical ventilator from 1 January 2000 to 30 June 2003. VAP group defined as neonates who had pneumonia with mechanical ventilation longer than 48 hours. They were classified into VAP group(n=13) and control group (n=37) and the prevalence, microorganisms cultured from the endotracheal tube tip and risk factors were investigated. Results : The prevalence of VAP was 26.0%(n=13) and the most dominant microorganism cultured in our NICU was methicillin-resistant coagulase negative staphylococcus(MR-CNS) in 4 cases. Other microorganisms were Pseudomonas, Enterobacter, methicillin-resistant Staphylococcus aureus(MRSA) and Klebsiella. Gestational age, birth weight, Apgar score, respiratory distress syndrome, retinopathy of prematurity, bronchopulmonary dysplasia, sepsis, renal failure, pulmonary hemorrhage, pneumothorax were not different significantly between two groups except intraventricular hemorrhage(P<0.001) and patent ductus arteriosus(P<0.05). Duration of hospital stay and mortality rate were also not different significantly. Conclusion : VAP occurred at a significant rate among mechanically ventilated NICU patients. Despite of limitation of encotracheal tip culture, the most common microorganism was MR-CNS. We should be aware of occurrence of VAP in NICU neonate who were with mechanical ventilator and should treat with great care.

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Evaluation of reverse torque value of abutment screws on CAD/CAM custom-made implant abutments (CAD/CAM을 이용한 맞춤형 임플란트 지대주의 나사 풀림 토크 평가)

  • Lee, Chang-Jae;Yang, Sung-Eun;Kim, Seok-Gyu
    • The Journal of Korean Academy of Prosthodontics
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    • v.50 no.2
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    • pp.128-134
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    • 2012
  • Purpose: The purpose of this study was to compare the screw joint stability between the CADCAM custom-made implant abutment and the prefabricated implant abutment by measuring the reverse torque value after cyclic loading. Materials and methods: Twelve screw type implants (Implantium, Dentium Co., Seoul, Korea) were embedded in aluminum cylinder with acrylic resin. The implant specimens were equally divided into 3 groups, and connected to the prefabricated titanium abutments (Implantium, Dentium Co., Seoul, Korea), CADCAM custom-made titanium abutments (Myplant, Raphabio Co., Seoul, Korea) and CADCAM custom-made zirconia abutments (Zirconia Myplant, Raphabio Co., Seoul, Korea). The CAD-CAM milled titanium crown (Raphabio Co., Seoul, Korea) was cemented on each implant abutment by resin cement. Before cyclic loading, each abutment screw was tightened to 30 Ncm and the reverse torque value was measured about 30 minutes later. After the crown specimen was subjected to the sinusoidal cyclic loading (30 to 120 N, 500,000 cycles, 2 Hz), postloading reverse torque value was measured and the reverse torque loss ratio was calculated. Kruskal-Wallis test was used for statistical analysis of the reverse torque loss ratio. Results: The CADCAM custom-made titanium abutments presented higher values in reverse torque loss ratio without statistically significant differences than the prefabricated titanium abutments ($P$>.05). Reverse torque loss ratio of the custom-made zirconia abutments was significantly higher compared to that of the prefabricated titanium abutments ($P$=.014). Conclusion: Within the limitation of the present $in-vitro$ study, it was concluded that there was no significant difference in screw joint stability between the CADCAM custom-made titanium abutments and the prefabricated titanium abutments. On the other hand, the CADCAM custom-made zirconia abutments showed lower screw joint stability than prefabricated titanium abutments.

Change of Blooming Pattern and Population Dynamics of Phytoplankton in Masan Bay, Korea (마산만 식물플랑크톤의 대발생 양상의 변화와 군집 동태)

  • Lee, Ju-Yun;Han, Myung-Soo
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.12 no.3
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    • pp.147-158
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    • 2007
  • To clarify the bloom pattern and species succession in phytoplankton community, the population dynamics with the determination of physico-chemical factors have been studies in Masan Bay, the south sea of Korea, for the periods November 2003-October 2004. Concentration of $NH_4-N$ was always higher than that of $NO_3-N$, which was similar level as compared to other costal areas. $PO_4-P$ concentration was lower than those in other coastal areas but similar to oligotrophic environments. Thus, phosphate seems the limiting nutrient rather than nitrogen. $SiO_2-Si$ concentration was also low as compared to other costal areas. Si:P ratio was low from autumn to winter, suggesting silicate and/or phosphate limitation during this period. The cell density of phytoplankton was high in winter 2003 and early autumn 2004. The carbon biomass was high in winter 2003 and summer 2004. And chlorophyll-a concentration was high in late autumn 2003 and summer 2004. Among 78 species of phytoplankton found in the bay during the investigated period, dominant species were two diatoms of Cylindrotheca closterium, Skeletonema costatum, and three dinoflagellates of Heterocapsa triquetra, Prorocentrum minimum, P. triestinum, and one raphidophyte of Heterosigma akashiwo. P. minimum dominated from late autumn to winter, but it was replaced by H. triquetra in late winter. P. triestinum dominated from late spring to early summer. Simultaneously, H. akashiwo cell density steadily increased, and it became dominant with C. closterium in late summer. With decreasing of H. akashiwo and C. closterium, S. costatum became the most dominant species in autumn. The canonical analyses showed that total phytoplankton cell density related to diatom cell density and it was affected by temperature, and concentrations of $NO_3-N\;and\;PO_4-P$. The carbon bio-mass and $chlorophyll-{\alpha}$ concentration related to diatom- and dinoflagellate cell densities and these were affected by flagellate cell density, salinity, and concentrations of $SiO_2-Si\;and\;PO_4-P$. Last six years monitoring data in Masan city obtained from Korean Meteorological Agency indicates gradual increase in air temperature. And the precipitation decreased especially in spring season. The winter bloom found in 2003 may be caused by the increase in the temperature and this bloom subsequently induced the nutrients depletion, which continued until next spring probably due to no precipitation. Therefore, the spring bloom, which had been usually observed in the bay, might disappear in 2004.