• 환경생물
• /
• 제34권3호
• /
• pp.177-182
• /
• 2016

부화장에서 폐기하는 달걀을 Bacillus amyloliquefaciens를 이용 분해하여 비료화하는 데 있어 발생하는 악취는 폐기물 처리에 있어 중요한 제한요소 중 하나이다. 이런 문제를 해결하기 위하여 두 개의 효모, Saccharomyces cerevisiae KACC 30008와 KACC 30068를 사용하여 실험하였다. 효모 균주는 모두 세균만을 사용하여 분해 처리하였을 때보다 섞어서 사용한 경우 암모니아 발생을 약 35.4% 감소하였고, 두 균주를 같이 섞어 사용한 경우는 57.1% 감소시켰다. 두 균주는 황화수소 또한 42%와 90.4%씩 각각 감소시켰고, 동시에 두 균주를 같이 사용했을 때에는 황화수소 발생을 98.5% 감소시켰다. 메틸메르캅탄의 경우 KA30008은 감소시키지 못하였으나 KA30068은 40%, 두 균주를 함께 사용한 경우는 66.7% 감소시켰다. 전체적으로 본 연구는 효모의 처리가 B. amyloliquefaciens를 사용하여 폐달걀 분해 시 악취 발생을 저감하는 효과를 더 증진시킴을 보여주었다.

• 한국수산과학회지
• /
• 제36권6호
• /
• pp.591-595
• /
• 2003

Settlement of larvae, growth, and survival of juvenile abalone (Haliotis discus hannai) were examined after feding of 5 species of benthic diatoms (Cocconeis suctellum, Navicula sp Nitzschia longissima Bacillavia paxillifera, Licmophora flabellata). All of the benthic diatoms were isolated from natural populations on plastic plates for the abalone. The settlement of larvae, shell growth, and survival rate of juvenile abalone varied by diatoms species. The highest settlement rate of larvae was $43.1\%$ with the Cocconeis suctellum diet. Daliy growth rate reached a maximum at 64.1 ${\mu}m/day$ with the Navicula sp. diet and a minimum at 22.4 ${\mu}m/day$ with the Licmophora flabellata diet. Survival rate of the juvenile abalone was highest at $62.0\%$ with the Navicula sp., Cocconeis suctellum , and Nitzschia longissima diets. Survival rate of the Juvenile abalone was significantly higher than the control group with mixed diatom population diets (P<0.05). Therefore, diatom . species composition in diets can be a controling factor for the settlement, growth, and survival rates of Juvenile abalone.

• 한국수산과학회지
• /
• 제35권6호
• /
• pp.686-695
• /
• 2002

Samples of Corbicula ( Corbicula) japonica Prime of Namdae Stream in Gangnung were collected from November 2000 to October 2001. Age of C. (C.) japonica was determined from the rings on the shell, The shell length of the samples ranged from 8 mm to 38 mm. The ring on the shell was formed once a year in March. Von Bertalanffy's growth parameters were estimated using a nonlinear regression method, asyinptotie shell length ($L_{\omega}$) was 48,98 mm, K was 0.20421year, theoretical age at 0 shell length $(t_0)$ was 0.3169 year, and asymptotic total weight ($W_{\omega}$) was 41.37 g. The formula of allomeky between shell length (L, mm) and total weight (W, g) of the brackish water clam was W=3.42$\times$10^{-4}L^{3}. The annual survival rate was estimated at 0.3799, instantaneous coefficient of natural mortality was 0.5007/year, and instantaneous coefficient of fishing mortality was 0.46721year. The age at first capture was estimated at 2.1593 year using shell length compositions of the brackish water clam, The current yield-per-recruit at 0.4672/year of fishing mortality was 0.6595 g. F_0.1 was estimated at 0.1865/year, Acceptable biological catch was estimated at 14.4 metric ton.

• ALGAE
• /
• 제37권3호
• /
• pp.213-226
• /
• 2022

Aquaculture is one of the fastest growing food producing sectors; however, intensive farming techniques of finfish have raised environmental concerns, especially through the release of excessive nutrients into surrounding waters. Biodiversity has been widely shown to enhance ecosystem functions and services, but there has been limited testing or application of this key ecological relationship in aquaculture. This study tested the applicability of the biodiversity-function relationship to integrated multi-trophic aquaculture (IMTA), asking whether species richness can enhance the efficiency of macroalgal bioremediation of wastewater from finfish aquaculture. Five macroalgal species (Chondrus crispus, Fucus serratus, Palmaria palmata, Porphyra dioica, and Ulva sp.) were cultivated in mono- and polyculture in water originating from a lumpfish (Cyclopterus lumpus) hatchery. Total seaweed biomass production, specific growth rates (SGR), and the removal of ammonium (NH₄⁺), total oxidised nitrogen (TON), and phosphate (PO₄^3-) from the wastewater were measured. Species richness increased total seaweed biomass production by 11% above the average component monoculture, driven by an increase in up to 5% in SGR of fast-growing macroalgal species in polycultures. Macroalgal species richness further enhanced ammonium uptake by 25%, and TON uptake by nearly 10%. Phosphate uptake was not improved by increased species richness. The increased uptake of NH₄⁺ and TON with increased macroalgal species richness suggests the complementary use of different nitrogen forms (NH₄⁺ vs. TON) in macroalgal polycultures. The results demonstrate enhanced bioremediation efficiency by increased macroalgal species richness and show the potential of integrating biodiversity-function research to improve aquaculture sustainability.

• 한국양식학회지
• /
• 제1권1호
• /
• pp.25-39
• /
• 1988

사육 조건하에서 넙치는 사육 수온이 $12^{\circ}C$에서 $14\~15^{\circ}C$로 상승하고 광선 주기가 10L/14D에서 14L/10D로 되는 시기에 성숙하여 산란하였다. 사육 환경하에서 사육된 어미의 산란 기간중 전반기에 산란된 수정란이 후반의 것에 비하여 양질의 알로서 종묘의 대량 생산시에는 전반의 수정란을 활용하는 것이 바람직하다.

• 한국어병학회지
• /
• 제24권1호
• /
• pp.19-27
• /
• 2011

The production of surf clam, Mactra veneriformis, an important fishery resource in Korea, has recently been decreasing. This study was carried out to examine effects of spawning on immune functions of this species. Total hemocyte count (THC), phenoloxidase (PO) activity, phagocytic activity, neutral red retention (NRR) time and antibacterial activity were assessed. Spawned clams showed reduction in THC, PO, phagocytic activity and NRR times compared with unspawned ones. While spawning event did not elicit any change of antibacterial activity in both spawned and unspawned ones. This study indicates that spawning process decreases immune functions in the surf clams which could cause mortality increment and yield reduction.

• 수산해양교육연구
• /
• 제26권5호
• /
• pp.1075-1082
• /
• 2014

Monthly Screening of Pacific oyster, Crassostrea gigas, was surveyed by PCR for Ostreid herpesvirus(OsHV-1) infections from 2012 to 2013 in Korea. It was showed positive results in one hatchery in April and May 2012 and in oyster farming areas from August to November in 2013. The obtained sequences showed 99.3~99.5% homology with OsHV-1 ${\mu}var$(Accession Number: HQ842610) and 96.2~96.3% homology with OsHV isolated from Korea(Accession Number: AY509253).

• 한국수산과학회지
• /
• 제36권3호
• /
• pp.317-320
• /
• 2003

Morphologically similar fish species were subjected to the random amplified polymorphic DNA (RAPD) analysis using universal rice primer (URP). The fish species tested were sea basses (Lateolabrax japonicus and L. maculatus), eels (Anguilla japonica, A. bicolor bicolor, A. rostrata, and A. anguilla), and flounders (Limanda yokohamae and L. herzensteinin). Highly reproducible RAPD patterns were observed with several potential species-specific markers. The results indicate that RAPD technique using URP is useful for distinguishing fish psecies in a rapid manner.

• Wind and Structures
• /
• 제4권2호
• /
• pp.85-100
• /
• 2001

The mechanism of wind-induced ovalling vibrations of cylindrical shells is numerically investigated by using a vortex method. The subject of this paper is limited to a two-dimensional structure in the subcritical regime. The aerodynamic stability of the ovalling vibrations in the second to fourth circumferential modes is discussed, based on the results of a forced-vibration test. In the analysis, two modal configurations are considered; one is symmetric and the other is anti-symmetric with respect to a diameter parallel to the flow direction. The unsteady pressures acting on a vibrating cylinder are simulated and the work done by them for one cycle of a harmonic motion is computed. The effects of a splitter plate on the flow around the cylinder as well as on the aerodynamic stability of the ovalling vibrations are also discussed. The consideration on the mechanism of ovalling vibrations is verified by the results of a free-vibration test.

• 한국양식학회지
• /
• 제3권1호
• /
• pp.31-37
• /
• 1990

Oreochromis속 틸라피아 10계통에 대한 세포유전학적 분석을 실시하였다. 염색체수(2n=44)와 각 염색체쌍은 10계통 모두에서 동일하였으며 heteromorphic한 성염색체는 어떠한 계통에서도 나타나지 않았다. 그러나 세포의 크기는 다양하여 O. niloticus는 핵의 부피가 21.0$\mu$ $m^3$, O. aureus는 22.4$\mu$ $m^3$로 가장 컸다.