• Journal of the korean society of oceanography
• /
• 제32권2호
• /
• pp.85-92
• /
• 1997

Seasonality in abundance and egg production was investigated for Calanus sinicus in Asan Bay, Korea, and feeding effort was measured in the laboratory condition. Although abundances of this species in this bay showed only one Peak in spring, egg Production showed two peaks, spring and fall, in this bay. Potential of year-round egg Production was also found. Food availability judged by the particulate organic carbon (POC) concentration was usually more than enough in this bay. High egg Production in fall resulted in spring Peak in abundance. But high egg Production in spring did not result in summer or fall Peak in abundance. Low abundances in summer and fall were believed to be the result of long range horizontal migration out to the central Part of the Yellow Sea. The highest average egg Production by the Population of this species was 16.3 eggs female-'day-'. Maximum e99 Production by an individual was 39.0 e99s female$^{-1}$ day$^{-1}$, which yielded 30.7% of specific egg Production rate in terms of body carbon content with the carbon contents of 44.44$^{\mu}$gC and 0.35 $^{\mu}$gC for individual adult female and egg, respectively. Clearance rate (F) measured in the laboratory condition decreased exponentially with the increase of food concentrations, as expected. The asymptote of F was 3.17 ml copepod$^{-1}$ h$^{-1}$. When this value and the minimum concentration of POC measured in the field were applied under the assumption of continuous feeding in the nature, the calculated gross efficient of egg production was 41.6% in case of average egg production of the population. Violation of the assumption of diurnal feeding rhythm and application of the minimum concentration of POC may offset the influence on calculation each other.

• 환경생물
• /
• 제28권3호
• /
• pp.125-132
• /
• 2010

하계 진해만 16개의 정점에서 해양생태계의 오염 정도를 평가하기 위해서 플랑크톤 건강 지수를 살펴보았다. 해양생태계 건강지수 산출은 부유성 플랑크톤 생물 엔테로박테리아 Escherichia coli, HB, ANF, HNF, HABs 그리고 섬모충류 등과 더불어 무기와 유기 오염원인 DOC, COD, 그리고 Chl.a 등을 각각 조사하였다. 그 중 플랑크톤 지수 산출은 오염압력의 반응에 민감한 Chl.a, HABs, HB, E. coli 등 4개의 지표를 시범적 선정하였다. 또한 점수산정기준은 과거자료를 바탕으로 통계학적 기법으로 해석하였으며, 그들 건강지수 등급도 4개로 나누었다. 그 결과 진해만 해역은 전반적으로 "좋음"의 B등급을 받았다. 본 연구에서 산출한 플랑크톤 건강지수는 진해만의 해양생태계 건강성 평가를 하기 위한 좋은 방법 중 하나로 고려하여도 될 것이다.

• 환경생물
• /
• 제20권1호
• /
• pp.46-54
• /
• 2002

1999년 2월부터 11월까지 강진만의 16개 조사정점에서 동물플랑크톤 군집의 특성을 파악하기 위하여 격월별 조사를 실시하였다. 동물플랑크톤은 9개의 분류군이 출현하였으며 평균 출현량은 2,028indiv. $m^{-3}$이었다. 월별 출현량은 2월에 최대 5,496 indiv. $m^{-3}$에서 11월에 최소 78 indiv. $m^{-3}$ 사이에서 변동하였다. 동물플랑크톤 중 요각류는 총 19종이 동정되었는데 월평균 출현량은 42-4,159 indiv. $m^{-3}$의 범위였고 Acartia omorii, Centrophages abdominalis, Paracalanus indicus 및 A. steueri가 우점하였다. 지각류는 4월에 최고값 765 indiv. $m^{-3}$로 출현하였다. 계절별로 2월에는 요각류 A. omorii와 Oithona davisae, 4월에 요각류 A. omorii, Eurytemora pacifica와 지각류 Evadne nordmanni, Podon polyphemoides, 6월에 요각류 Tortanus dextrilobatus와 십각류의 유생, 8월에 요각류 P. indicus와 지각류 E. tergestina와 Penilia avirostris, 10월에 요각류 A. erythraea, P. indicus, 그리고 11월에 요각류 P. indicus 및 모악동물 Sagitta crassa가 우점하였다.

• Ocean and Polar Research
• /
• 제29권4호
• /
• pp.411-418
• /
• 2007

We studied the bottom morphology and sedimentary environments of the Masan Bay using high-resolution Chirp seismic profiles and sediments data. According to deep-drilled core samples (up to 20 m thick) penetrated into the weathered rock basement, the sediments consist largely of three sediment types: the lower sandy gravel facies (Unit I) of 1-4 m in thickness, the middle sandy mud and/or muddy sand facies(Unit II) of 1-2 m thick and the upper mudfacies (Unit III) of over 10 m in thickness. The sedimentary column above the acoustic basement can be divided into two major sequences by a relatively strong mid-reflector, which show the lower sedimentary sequenc e(T) with parallel to subparallel internal reflectors and the upper sedimentary sequence(H) with free acoustic patterns. Acoustic basement, the lower sedimentary sequence (T), and the upper sequence (H) are well correlated with poorly sorted massive sandy gravels (Unit I), the sand/mud-mixed sediment (Unit II), and the muddy facies(Unit III), respectively. The acoustic facies and sediment data suggest that the Masan bay is one of the most typical semi-enclosed coastal embayments developed during the Holocene sea-level changes. The area of the Masan Bay reduced from about $19\;km^2$ in 1964 to about $13\;km^2$ in 2005 by reclamation, and its bottom morphology changed as a result of dredging of about $2{\times}10^7\;m^3$.

• 월간경쟁저널
• /
• 제145호
• /
• pp.36-47
• /
• 2009

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2017년도 학술발표회
• /
• pp.185-187
• /
• 2017

• Ocean and Polar Research
• /
• 제25권1호
• /
• pp.31-40
• /
• 2003

In August-September 2001, 15 samples of bottom sediments were collected in the inner, middle and open parts of Amursky Bay near Vladivostok, Russia, and barfin plaice Pleuronectes pinnifasciatus was sampled from the inner and the middle locations of the bay. In the sediments from all three sites elevated concentrations of several heavy metals, i.e. Zn ($102-115{\mu}/g$ dry weight), Ni $(70-73{\mu}g/g)$ and Cu $(27-35{\mu}g/g)$ were discovered. The contents of oil hydrocarbons were very close to or slightly higher than the maximal normal environmental background level, $100{\mu}g/g$ dry weight. The sediments contained negligible amounts of hexachlorocyclohexane, while DDT concentrations were quite high (1.7-16.3ng/g dry weight). Generally, there were no substantial differences in the pollution levels of the locations studied and our results resembled those reported for Amursky Bay in the 1990s. Surprisingly, in 2001 'fiesh' DDT comprised 70-85% of the total DDT content in sediment from all the locations studied. In fish liver total DDTs concentrations were 212.8 and 122.54 ng/g wet weight for the inner and the middle locations, respectively, and 'fresh' DDT comprised 35 and 64% of DDTs, respectively. These results provide evidence of recent input of DDT from an unknown source into the ecosystem of Amursky Bay. Histopathological changes revealed in the plaice liver (vacuolization of hepatocytes, coagulative necrosis of hepatocytes, inflammatory reaction, and necrosis of epithelial cells of bile ducts) are probably connected with an intensive metabolism of DDT in the fish organism. No histological and histomorphometric differences were found in the state of the interrenal tissue. Similar condition of the liver and the interrenal tissue in barfin plaice sampled from the inner and the middle locations of Amursky Bay may be explained by the absence of great differences in the pollution levels of these sites.

• The Korean Journal of Ecology
• /
• 제6권3호
• /
• pp.167-176
• /
• 1983

Species composition, life form, biomass and soil properties of the halophyte communities were investigated from July to September, 1982. At the reclaimed land of Sanho-ri, sand dune of Jido, salt marsh of Suncheon Bay, and Somjin River estuary of Baealdo, species numbers were 26, 14, 13 and 7, dominant species were Salicornia herbaceae, Carex pumila and Suaeda japonica, respectively. Species composition of the 4 investigated areas was 13 families, 25 genera and 39 species, and of them, 10 families, 21 genera and 24 species were attributed to halophytes. Out of 22 life forms, the representative for Jido was $ G-D_4-R_1-3-e.t$and those for the other sites were Th-G4-R5-e. Above ground biomass of all species for Sanho-ri, Jido, Suncheon Bay and Baealdo were 441.3, 202.0, 150.7 and 353.3 g.dw/m2 and the ratios of above ground biomass halophytes to all species were 93.5, 92.7, 90.8 and 100%, respectively. The leading dominant species formed a continuum according to the salt gradiant. The similarity between Baealo and Suncheon Bay was relatively high, and Jido was quite different from the others in species composition. Aster tripolium was stenohaline and appeared at the low salt concentration, but Suaeda maritima and Suaeda asparagoides were duryhaline and occured at the relatively high salt concentration.

• 한국수산과학회지
• /
• 제36권5호
• /
• pp.495-499
• /
• 2003

Age and growth of purpulish Washington clam (Saxidomus purpuratus) was investigated from 480 samples monthly collected from January to December 2002 in Jinhae Bay, Korea. Examination of outer margins of the shell revealed that the translucent zone was formed once a year from March to April, it can be used as annulus. Ages were determined from ring radius of shell, and maximum age of the the clam was 9 years. The spawning period was from May to October, and the main spawning occurred in July. The relationship between shell length (SL) and shell height (SH) was $SH=0.8405{\times}SL^{-4.9709}\;(R^2=0.97)$ and that between the shell length (SL) and total weight (TW) was $TW=0.9580{\times}10-4{\times}SL^{3.220}(R^2=0.97).$ The von Bertalanffy growth equation were $SL_t=125.57(1-e^{-0.2523(t+0.5367)},\;TW_t=549.26(1-e^{-0.2523(t+0.5367)})^{3.220}.$

• 한국수산과학회지
• /
• 제12권1호
• /
• pp.35-39
• /
• 1979

Examining the polychaetous annelids collected from the Yellow $Sea(30^{\circ}20'\;N\;Lat.\;124^{\circ}35'\;E\;Long)$ Jinhae Bay, Yeocheon Bay, Jeju Do and Weolpo. I found five species which should be added in the list as new to the polychaetous annelids fauna of Korea. In the present study five species are reported morphological descriptions. Consquently, a total 125 species of polychaetous has been reported(Kamita and Sato 1941; Paik 1972, 1973a, 1973b, 1975a, 1975b, 1976, 1977, 1978, 1979; Lee 1976; Rho and Song 1974, 1975) in Korea.