• ALGAE
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• 제21권1호
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• pp.133-139
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• 2006

Outdoor cultivation of cyanobacterium Spirulina platensis was carried out for 40 days in a batch mode. A half concentration of the SOT based on the underground water was used as culture medium. Working volume was 5.7 tons with 0.2 m depth. During cultivation, mean water temperature, DO and light intensity were all in proper conditions for the S. platensis growth. The adjustment of pH to over 10 with Na2CO3 and addition of the 1.5% natural salt were very effective to delete contaminant organisms, Chlamydomonas moewusii and Chlorella minutissima occurred one after the other in the culture. The mean productivity of the biomass based on the dry cell weight from 14 to 25 days, after the contaminants were deleted, was 7.8 g ·m–2· d–1, which was relatively high productivity in that a half concentration of the SOT was used for the culture. Underground water used in the culture minimized contaminants invasion and addition of the 1.5% natural salt was effective to delete contaminants as well as acted as mineral supplement in outdoor cultivation of S. platensis. Harvesting using the floating activity of S. platensis was effective from mass floating in day time after overnight without agitation and illumination.

• 한국미생물·생명공학회지
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• 제27권2호
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• pp.166-171
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• 1999

This study was conducted to investigate the removal rate of nitrogen and phosphorus, and lipid production from a swine wastewater by Botryococcus braunii UTEX 572 in an outdoor photobioreactor. B. braunii successfully predominated in competition with bacteria and other algae, especially Oscillatoria, which were grown spontaneously in a secondary-treated swine wastewater, under the conditions of incubation temperature at $25^{\circ}C$ and increased inoculum amount at 287mg/l. There was a significant relationship between dry weight of B. braunii and absorbance of culture solution at 680mn(r2=0.967), suggesting that the latter is as good as the former commonly used for the measurement of algal biomass which is considerably time-consuming. The removal rates of COD, TOC, total nitrogen, and total phosphorus from the swine wastewater were 33.2$\pm$2.6% and 32.8$\pm$3.2, respectively, which showing no different between them. These results suggested that the mass cultivation of B. braunii in an outdoor photobioreactor could be used for the advanced treatment of swine wastewater and lipid production.

• 한국콘텐츠학회논문지
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• 제15권10호
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• pp.547-560
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• 2015

최근 국내에서 크게 증가하고 있는 아웃도어레크리에이션 열풍은 여가시간과 가처분소득의 증가뿐만 아니라 대중매체와 대중문화의 상호작용의 효과로 볼 수 있다. 국내에서 대중매체를 통해서 노출되는 아웃도어레크리에이션은 실질적으로 크게 증가하고 있고, 관련 산업분야도 급속도록 성장하는 것으로 나타났다. 리얼리티 프로그램 '아빠! 어디가?'의 경우에는 여러 아웃도어레크리에이션을 통해 놀이, 재미, 경쟁, 그리고 일탈적인 특성 등을 사실적으로 노출하고 있기 때문에 관광객의 내재적 특성인 놀이성 측면이 더욱 부각이 된다. 이에 본 연구에서는 대중매체를 통한 아웃도어레크리에이션의 노출이 잠재 아웃도어 레크리니셔트에게 어떠한 영향을 미치는지를 규명하고자한다. 이러한 의사결정과정을 규명하기 위하여 인간의 행동에 대한 설명력이 높은 계획된 행동이론에 성인의 재미와 놀이의 내재적 특성인 놀이성을 추가하였다. 연구결과, 놀이성은 태도, 주관적 규범, 지각된 행동통제에 크게 유의한 영향을 미치는 것으로 나타났고, 태도, 주관적 규범, 지각된 행동통제 또한 행동의도에 유의한 영향을 미치는 것으로 나타났다. 이는 일탈적 행동을 추구하는 아웃도어레크리에이션에서 놀이성이 큰 영향을 미치는 변인임을 규명하였다고 볼 수 있다.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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• pp.151-152
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• 2000

During in door or outdoor mass culture, Porphyra have been easily contaminated with bacteria, protozoa and microalgal species. Several axenic treatments for Porphyra thalli have been published (Polne-Fuller and Gibo 1984; Chen and McCracken 1993), but axenic techniques for neutral spores and conchocelis we not developed. In this work we describe the procedure for axenic isolation of neutral spores and conchocelis of Porphyra yezoensis (omitted)

• Fisheries and Aquatic Sciences
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• 제26권11호
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• pp.660-668
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• 2023

This study aimed to investigate the growth performance of far eastern catfish (Silurus asotus) on outdoor fish farms to obtain basic data for the domestic eastern catfish aquaculture industry. An outdoor fish farm was directly monitored from June 2018 to October 2019 to determine the farming conditions, growth performance, and water quality. The growth performance in 2017 was analyzed using data from the same fish farm. Three years of monitoring showed that the fish farm required approximately 5-6 months between stocking, harvesting, and selling an S. asotus batch. The growth parameters, namely, the weight gain rate (WGR), specific growth rate (SGR) for culture periods, SGR for feeding periods, and feed coefficient rate (FCR), were 4,664.7%, 1.27%, 2.43%, and 1.25 in 2017; 6,452.0%, 1.52%, 2.79%, and 1.42 in 2018; and 3,270.0%, 1.11%, 2.12%, and 1.38 in 2019, respectively. Moreover, the WGR was two-fold higher in 2018 than 2019, whereas the FCR was more effective in 2019 than 2018, presumably because of the stocking density. No mass mortality was observed during the water quality analysis. The results of this study provide basic data for the development of the catfish industry.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권6호
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• pp.338-348
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• 2003

In the past decade, considerable progress has been made in developing the appropriate biotechnology for microalgal mass cultivation aimed at establishing a new agro-industry. This review points out the main biological constraints affecting algal biotechnology outdoors and the requirements for making this biotechnology economically viable. One of them is the availability of a wide variety of algal species and improved strains that favorably respond to varying environmental conditions existing outdoors. It is thus just a matter of time and effort before a new methodology like genetic engineering can and will be applied in this field as well. The study of stress physiology and adaptation of microalgae has also an important application in further development of the biotechnology for mass culturing of microalgae. In outdoor cultures, cells are exposed to severe changes in light and temperature much faster than the time scale re-quired for the cells to acclimate. A better understanding of those parameters and the ability to rapidly monitor those conditions will provide the growers with a better knowledge on how to optimize growth and productivity. Induction of accumulation of high value products is associated with stress conditions. Understanding the physiological response may help in providing a better production system for the desired product and, at a later stage, give an insight of the potential for genetic modification of desired strains. The potential use of microalgae as part of a biological system for bioremediation/detoxification and wastewater treatment is also associated with growing the cells under stress conditions. Important developments in monitoring and feedback control of the culture behavior through application of on-line chlorophyll fluorescence technique are in progress. Understanding the process associated with those unique environmental conditions may help in choosing the right culture conditions as well as selecting strains in order to improve the efficiency of the biological process.

• 한국수산과학회지
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• 제5권2호
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• pp.45-49
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• 1972

1. Brachionus calyciflorus의 실외 시비 배양에서 $16m^2$의 콘크리이트 못에서 1ml당 약 100개체의 고밀도 배양이 가능하였으며, 발생 시작 후 $2\~3$일 째에 dipterex를 $0.16\~0.2ppm$유효 성분 농도로 살포하여 Daphnia등 다른 갑각류의 발생을 억제함으로써 약 2주일 동안 그 발생 상태를 유지할 수 있었다. 이 때 사용된 비료는 닭똥이 약 8kg이며, 수심은 30cm 전후로 하였다. 2. 수온 $20^{\circ}C$ 이하로 내려가면 그 발생이 극도로 저하한다. 3. Filinia longiseta등 소형 rotifer는 1ml당 약 1000개체의 고 밀도로 발생이 가능하나 dipterex에 대하여 대단히 약하며 앞으로 상세한 실험이 요청된다. 4. 실내에서 Brachionus calyciflorus를 배양할 때는 그 먹이인 녹조류를 실외의 못에서 배양하거나 또는 태양광선을 이용할 수 있는 장치를 실내에 하는 것이 좋다고 인정된다. 5. marble gourami의 어린 자어에 Brachionus calyciflorus를 먹이니 그 성장이 잘 되었다. 이 때 dipterex를 사용하여 다른 갑각류를 억제하면서 발생시킨 것을 바로 먹여서 자어에게 아무런 지장을 초래하지 않았다.

• 생물환경조절학회지
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• 제7권3호
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• pp.268-274
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• 1998

열수지 경류센서에 의한 멜론의 흡수량 측정오차는 최저 0.3%에서 최대 31.8% 범위 내에 있었으며, 일사량 20MJ.m$^{-2}$ .d$^{-1}$에서는 오차가 적었으나 일사량이 이보다 많아지면 많아질수록 센서측정 경류량이 실측양액 소비량보다 적어지는 경향이었고 일사량이 적어질수록 센서측정 경류량이 실측양액 소비량보다 많아지는 경향이었다. 센서간의 오차는 최저 0.1%에서 최대 13.0%의 오차율을 보였다. 열수지센서측정 경류량은 일사량이나 온도와 고도의 부의 상관관계를 보였다. 그러므로 이를 이용 보정계수를 산출하면 보다 정확한 멜론의 경류량을 측정할 수 있을 것으로 판단되었다.

• Ocean and Polar Research
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• 제35권4호
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• pp.407-414
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• 2013

One of the most important challenges facing the Spirulina mass cultivation industry is to find a way to reduce the high production costs involved in production. Although the most commercial medium (Zarrouk's medium) for Spirulina cultivation is too expensive to use, it contains higher amount of $NaHCO_3$ (16.80 g $L^{-1}$), trace metals and vitamin solutions. The purpose of this study was to increase the efficiency of Spirulina platensis biomass production by developing a low-cost culture medium at an isolated tropical island such as Chuuk State, Federated States of Micronesia (FSM). This study set out to formulate a lowcost medium for the culture of S. platensis, by substituting nutrients of Zarrouk's medium using fertilizer- grade urea and soil extract with a different concentration of carbon source under natural weather condition. In order to select a low-cost culture medium of S. platensis, 10 culture media were prepared with different concentrations of nitrogen (urea and $NaNO_3$) and $NaHCO_3$. The highest maximum specific growth rate (${\mu}max$) and mass production were 0.50 $day^{-1}$ and 1.05 g $L^{-1}$ in modified medium ($NaHCO_3$ 7.50 g $L^{-1}$, urea 2.00 g $L^{-1}$ without $NaNO_3$) among all the synthesized media. Protein (56.14%) and carbohydrate (16.21%) concentrations of the lyophilized standard samples were estimated with highest concentration of glutamic acid (14.93%). This study revealed that the use of a low concentration of urea and $NaHCO_3$ with soil extract was an affordable medium for natural mass cultivation in the FSM.

• ALGAE
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• 제36권4호
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• pp.327-332
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• 2021

Raw material of gelidioid red algae yielding high-quality agar has been in short supply due to overharvesting, but in situ farming of gelidioids has not been practical due to their slow growth. To produce vegetative seedstock of a cosmopolitan species, Pterocladiella capillacea, we investigated the number and length of regenerated branches arising from sectioned fragments during 3 weeks of laboratory culture at 10, 15, 20, and 25℃. All sectioned fragments formed axis-like branches mostly from the upper cut edge and stolon-like branches mostly from the lower cut edge, showing a high capacity of regeneration and intrinsic bipolarity. At 20℃, the number of regenerated branches increased to 2.74 ± 1.29 on the upper cut edge and 4.26 ± 2.66 on the lower cut edge. Our study reveals that the use of fragments bearing regenerated branches as seedstock can be a simple method to initiate fast propagation for mass cultivation in the sea or outdoor tank.