• Ocean and Polar Research
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• 제44권3호
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• pp.261-267
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• 2022

We derived a length-weight relationship for Calanus sinicus off Busan, Korea in spring to estimate the biomass of the C. sinicus population around Korean waters, and compared it with the previously derived equations. The developmental stages and prosome length of C. sinicus used in the relationship ranged from 1,376-1,540 ㎛ for copepodite 4 (CIV), 1,753-1,971 ㎛ for copepodite 5 (CV), and 2,160-2,283 ㎛ for adults (CVI). Dry weight and carbon content were measured from a total of 26 replicates. Length-weight relationships derived in the present study are as follows: log C = 3.342 log PL - 9.449, log DW = 3.394 log PL -9.219, where C is carbon content (㎍), DW is dry weight (㎍), and PL is prosome length (㎛). When comparing the present regression equation of length-weight for C. sinicus with the previous one, our regression equation showed an average carbon estimate to a given range of mean prosome length. The length-weight relationship of C. sinicus in the present study can be used to better estimate the biomass of the C. sinicus population in the coastal waters of Korea.

• Journal of the korean society of oceanography
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• 제33권1-2호
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• pp.28-34
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• 1998

Variations in abundance, size and population structure of Calanus sinicus were studied in the southern waters of Korea in connection with hydrographic conditions during 1991-1992. Abundance was high in April and low in August. This species was concentrated inshore of a coastal temperature front, or around the temperature front in April. The 1st-3rd copepodites dominated in February and April, and adults in August. The mean population stages in February and April were younger than those in other survey months. This suggests that this species mainly reproduced during winter-early spring. In prosome length, the 1st-4th copepodites were larger in April than in other survey months, and the 5th copepodite and adult were the largest in February. Mean prosome length of C. sinicus showed weak inverse relationship with sea water temperature, but it was not statistically evidenced.

• 환경생물
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• 제36권4호
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• pp.456-462
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• 2018

The purpose of this study was to assess cross-generational effects of bisphenol A exposure in benthic copepods, Tigriopus west. Nauplii (<24 hours old) were exposed to graded concentrations of bisphenol A, and toxicity end-points such as survival, development, sex ratio, and fecundity were measured. $F_1$ generations were grown under innoxious conditions, and similarly assessed. Significant differences were observed in development of nauplii and copepodites, between exposed and non-exposed copepods; however, there were no differences in survival of nauplii or copepodites, sex ratio, or brooding rate in parental generation. In contrast, in the $F_1$ generation, there were significant differences between the control group and exposed group in survival and development of nauplii. Length, width, and biomass of parental and $F_1$ generations were reduced in the exposed group compared to the control group. In addition, some deformities, such as swelling of the prosome, abnormally shaped egg sac, and dwarfism were observed after exposure to bisphenol A. So, our study demonstrates that a cross-generation toxicity test and monitoring of morphological deformities in harpacticoid copepods, can be useful for development of potential bioindicators for environmental monitoring, and assessment of chemical impact.

• 한국해양학회지
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• 제28권3호
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• pp.202-211
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• 1993

해양 부착상 규조류 pseudohimantidium pacificum에 관하여 주사전자현미경 및 광 학현미경을 통한 미세구조, 형태적 변이와 지리적 분포를 연구하였다. 세포의 정축과 횡축의 길이는 기왕의 보고와 유사하였으나 순상돌기의 수는 이보다 2~3개 더 많아 변이가 뚜렸하였다. 조선(striae)의 수도 기보고와 비슷하였고, 이의 모양은 현재까지 둥근형으로 보고되어 있으나 본 연구에서는 긴타원형이었다. 한편 본 규조류는 부유생 활을 할 뿐 아니라 동물부유생물 중 요각류 Corycaeus affinis의 흉각과 두부의 촉각 주변에 많이 부착하고 있었다. 본종이 한국의 남서해역에서 분포하고 있음을 확인하였 던 사실은 이 종이 북태평양의 황해에 37$^{\circ}$30'N까지 분포함을 말해준다.

• 한국수산과학회지
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• 제31권2호
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• pp.288-295
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• 1998

한국 동해 남부 연안 일광만에서 요각류 Arasrtia steueri의 알 생산력을 조사하였다. 실험실에서 온도 및 엽록소 $\alpha$ 농도와 알 생산력간의 관계식을 유도한 후, 현장의 수온과 엽록소 $\alpha$ 농도를 적용하여 현장 개체군의 알생산력을 추정하였다. 알의 평균 크기는 $80.52{\mu}m$이었고, 성체 암컷의 두흉부 길이와 알의 크기간에는 유의한 상관이 없었다. 현장 개체군의 알 생산력은 $0.32\~63.32{\mu}gC\;m^{-3}d^{-1}$ (평균 $13.33{\mu}gC\;m^{-3}d^{-1}$)이었으며, 알의 수로 나타내 면 $7.1\~1407.1\;eggs\;m^{-3}d^{-1}$(평균 $296.1\;eggs\;m^{-3}d^{-1}$)이었다. 암컷 한 마리당 알 생산력은 $5.4\~12.5\;eggs\;female^{-1}d{-1}$(평균 $8\;eggs\;female^{-1}d{-1}$)이었으며, 비알 생산율은 $0.028\~0.117\;d^{-1}$(평균 $0.064\;d^{-1}$)로 나타났다. 본 연구에서 추정된 알 생산력 (성체 암컷의 탄소 무게의 백분율)은 과소 평가된 것으로 나타났는데, 성체의 알에 대한 잠재적인 포식 가능성이 이러한 낮은 알 생산력과 관련이 있는 것으로 판단된다.