• 제목/요약/키워드: Pots and field experiments

검색결과 21건 처리시간 0.038초

붕장어 통발의 개량 (Improvement of Sea Eel Pots)

  • 고관서;권병국
    • 한국수산과학회지
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    • 제20권2호
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    • pp.95-105
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    • 1987
  • 어획성능이 우수한 튜브통발의 적정규격을 규명하기 위하여 규격이 다른 실험용 튜브통발을 여러 가지로 제작하여 수조실험과 해상실험을 실시하였다. 수조실험에서는 튜브, 깔때기 및 혀그물의 적정규격을 규명하였고, 해상실험에서는 수조실험에서 규명한 개량형 튜브통발과 재래식 플라그틱통발과의 어획성능을 비교 검토하였다. 본 연구의 결과를 요약하면 다음과 같다. 1. 붕장어는 통발침지 15분이내에 전체입망중 $90\%$이상이 입망하였다. 2. 개량형 튜브통발과 재래식 플라스틱통발의 구조적 차이점은 구멍이 없는 튜브의 양단에 입구가 있으며 깔때기의 끝에 양쪽으로 봉합선을 넣어 납작하게 한 2중혀그물을 부착하였고 통발의 중앙부에 그물로 만든 이료주머니를 고정시킨 점으로 압축된다. 3. 개양형 튜브통발의 적정규격은 (1) 튜브 : 직경 $12\~13\times$길이 80cm, 2) 깔때기 : 깊이 $5\times$안쪽링의 직경 6cm, (3) 혀그물 : 길이 10cm 이다. 4. 개량형 튜브통발의 어획성능이 재래식플라스틱 통발보다 약 2.3배 우수하였다.

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동해안 울진해역 원통형 고둥 통발의 재질별 어획 성능 (Catching efficiency of the whelk pot in accordance with the pot materials in the Uljin waters, East sea)

  • 안희춘;배재현;박창두;박종명;홍성익;윤병선;김병관;김성훈
    • 수산해양기술연구
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    • 제53권1호
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    • pp.1-11
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    • 2017
  • Fishing pots are one of the important fishing gears in our coastal and offshore fisheries. In terms of a sustainable use of marine resources, there are concerns about the ghost fishing by lost pots. It is reported that 10 to 70% of the pots are abandoned or lost annually. This study is to compare the catching efficiency of drum type whelk pots that are made of biodegradable nets to those made of the ordinary nets, in the eastern coast of Korea. Five types of drum pots were used with combination of biodegradable nets and ordinary (PA, PE) nets applied to the main and funnel parts of the pots: pots with biodegradable nets (Bio+Bio); pots with PE net (PE+PE); pots with body and funnel made of biodegradable nets and PE nets respectively (Bio+PE); pots with body and funnel made of PE nets and PA nets respectively (PE+PA); pots with body and funnel made of PE nets and biodegradable net respectively (PE+Bio). Field experiments were conducted from June $18^{th}$, 2015 to August $7^{th}$, 2015 using a commercial fishing vessel in the Uljin waters on the eastern coast of Korea. Two fleets of pots with one hundred in each, 20 pots of each type, were casted for 8 to 15 days to analyze their catching efficiency. The catch of target species, whelks, was 202,563.0 g with catch rate of 38.7% of the total catch, while the bycatch was 320,709.7 g with the rate of 61.3% of the total catch. The catch of whelks was the highest in the Bio+PE pots (46,020.3 g), followed by the Bio+Bio pots (42,027.5 g), the PE+Bio pots (41,849.9 g) and the lowest being PE+PE pots (38,054.2 g). Compared to the conventional pots, the pots with biodegradable nets on the body or entrance part had slightly higher catch rate for both the target species and the bycatch. The PE+PE had the lowest catch rate. There is no significant difference in catch between the pots with biodegradable nets and the ordinary nets for the target species such as Buccinum opisthoplectum, Neptunea eulimata, Buccinum striatissimum. Consequently, using biodegradable nets for the conventional whelk pots can reduce ghost fishing by lost gears while keeping the performance of the pots.

통발어구의 어획기구 및 개양에 관한 연구 4. 민꽃게통발의 개량실험 (Fishing Mechanism of Pots and their Modification 4. An Experiment for Modifying the Pot for Crab, Charybdis japonica)

  • 김대안;고관서
    • 한국수산과학회지
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    • 제23권4호
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    • pp.310-314
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    • 1990
  • 본 실험에서는 민꽃게 통발의 가장 바람직한 형 및 구조를 확정하기 위해 사구원통형과 사구각주형 통발을 고안하고, 수조실험 및 해상실험을 통해 그들의 민꽃게 유입성능 및 어획성능을 재래의 이구각주형 및 이구원통형 통발과 비교하였다. 그 결과, 수조실험을 통한 유입성능은 사구식에서 좋고 이구식에서 나쁜 경향이었는데, 구체적으로는 이구식의 경우 각주형보다 원통형에서 약간 더 좋았고, 사구식의 경우는 원추형보다 각주형에서 약간 더 좋았다. 해상실험을 통한 어획성능도 전체적으로는 비슷하였는데, 사구원추형이 이구원통형과 어획의 유의차가 없다는 것만이 달랐다. 따라서, 민꽃게 통발의 가장 바람직한 형은 사구각주형이라는 것을 알 수 있었다.

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Effect of Soil Amendments on Arsenic Reduction of Brown Rice in Paddy Fields

  • Kang, Dae-Won;Kim, Da-Young;Yoo, Ji-Hyock;Park, Sang-Won;Oh, Kyeong-Seok;Kwon, Oh-Kyung;Baek, Seung-Hwa;Kim, Won-Il
    • 한국토양비료학회지
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    • 제51권2호
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    • pp.101-110
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    • 2018
  • There is an increasing concern over arsenic (As) contamination in rice since Codex Committee on Contaminants in Food (CCCF) discuss on maximum levels for As in rice in 2010. This study was conducted to reduce As concentration in rice by soil amendment treatments in paddy field soils contaminated by As. The selected four amendments were poultry manure, agri-lime, steel slag, and gypsum with the addition of 3% or 5% (w/w) on a dry basis. The As reduction effect could not be verified, as a result of the pot test by adding poultry manure to the paddy soil around the mine located in Yesan. Among the agri-lime treated rice cultivated pots, the As concentration increased up to 32.1%. On the other hand, the content of As in the sample pots treated with steel slag and gypsum decreased by 65.4% and 63.4%, respectively. On the basis of the results of these pot experiments, the field test was carried out in the As polluted rice field around the mine located in Yesan, and when the four amendments were treated, the As content in the brown rice reduced in all the amendment treatments compared with the control plot. The As reduction in brown rice of the amendment was confirmed to be higher efficiency by the order of gypsum > steel slag > poultry manure > agri-lime. As a result of pot experiments using paddy soil around the mine located in Seosan, As stabilization efficiency in rice and As reduction effect could not be determined by comparison to the control. From the rice cultivated from agri-lime treated pot, As concentration increased by 15.8% in rice. On the other hand, the As content of the pots treated with steel slag and gypsum decreased by 39.1% and 60.2%, respectively. In conclusion, distinguished As reducing effectiveness could be expected by soil amendment treatments for rice cultivation.

잎마름역병 저항성 육종을 위한 토마토 유전자원의 저항성 평가 (Evaluation of Tomato Genetic Resources for the Development of Resistance Breeding Lines against Late Blight)

  • 김병섭
    • 식물병연구
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    • 제18권1호
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    • pp.35-39
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    • 2012
  • Phytophthora infestans에 의해 발생하는 토마토 잎마름 역병은 전 세계적으로 발생하여 토마토 생산에 막대한 피해를 준다. 이 병의 방제를 위하여 저항성 품종의 이용은 매우 중요하다. 저항성 품종육종의 초기 및 본 육종에서 토마토 유전자원의 저항성 평가는 매우 중요하다. 본 연구는 2009년에 유묘 및 성체식물을 대상으로 78종의 토마토 시판 품종과 계통에 대한 잎마름역병 저항성을 검정하였다. Legend를 포함한 모든 시판 품종은 감수성이지만, California 대학에서 분양 받은 KNU-2, KNU-6-1, KNU-11, KNU-13, KNU-14-1 계통과 저항성 유전자 Ph-3를 가지고 있는 L3708, $AV107-4{\times}L3708$, $07-15{\times}L3708$, $BS67{\times}L3708$$06-9-62A{\times}06-9-62A$ 계통은 고도의 저항성인 것으로 나타났다. 본 연구에서 선발된 토마토 잎마름역병에 고도의 저항성을 가지는 10계통은 저항성 품종육종을 위한 유용한 자원으로 활용될 수 있다.

Trace element levels and selenium uptake in cereals grown in lower Austria

  • Sager M.;Hoesch J.
    • 한국지구물리탐사학회:학술대회논문집
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    • 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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    • pp.479-492
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    • 2003
  • Wheat, barley, rye, and maize were grown in field and pot experiments at various non-contaminated soils in order to establish uptake rates for added selenate, and to find baseline concentrations for various soil types. Edible parts (grains) and stalks of the crops were analyzed separately for Se, as well as for Ca, Cu, Fe, Mn, P, S, and Zn. The addition of Na-selenate in admixture with the NPK 20:8:8 fertilizer had no influence on the composition of the other elements investigated. The proportions of added nitrate: selenate, and sulfate:selenate were kept constant. The Se- uptake rate differed among the cereals tested, it was highest for winter wheat. Utilization of added Se in the field ranged from $0,4-4,7\%$, and and in the pots from $3,3-5,4\%$, it was markedly lower in clay soil. Whereas P and Zn were preferably found in the grains, Ca-Fe-Mn-S got enriched in the stalks. For the fields, the location had some influence upon Fe, Mn, and Zn, whereas it was not important for P, S, Cu, and strikingly, Ca. Pot and field experiments on similar soils led to different results, except for P and S. Maize (whole grains) was significantly lower in Ca, Cu, and Mn, and might even cause trace element deficiencies, if exclusively fed. Few correlations between the trace elements investigated led to the conclusion that most element contents were governed by plant metabolism. Variations of mobile Fe in the soils were balanced by uptake into the stalks. The data are compared with data from other presumably non-contaminated sites.

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Effectiveness of Rhizobacteria Containing ACC Deaminase for Growth Promotion of Peas (Pisum sativum) Under Drought Conditions

  • Zahir, Z.A.;Munir, A.;Asghar, H.N.;Shaharoona, B.;Arshad, M.
    • Journal of Microbiology and Biotechnology
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    • 제18권5호
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    • pp.958-963
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    • 2008
  • A series of experiments were conducted to assess the effectiveness of rhizobacteria containing 1-aminocyclopropane-1-carboxylate (ACC) deaminase for growth promotion of peas under drought conditions. Ten rhizobacteria isolated from the rhizosphere of different crops (peas, wheat, and maize) were screened for their growth promoting ability in peas under axenic condition. Three rhizobacterial isolates, Pseudomonas fluorescens biotype G (ACC-5), P. fluorescens (ACC-14), and P. putida biotype A (Q-7), were selected for pot trial on the basis of their source, ACC deaminase activity, root colonization, and growth promoting activity under axenic conditions. Inoculated and uninoculated (control) seeds of pea cultivar 2000 were sown in pots (4 seeds/pot) at different soil moisture levels (25, 50, 75, and 100% of field capacity). Results revealed that decreasing the soil moisture levels from 100 to 25% of field capacity significantly decreased the growth of peas. However, inoculation of peas with rhizobacteria containing ACC deaminase significantly decreased the "drought stress imposed effects" on growth of peas, although with variable efficacy at different moisture levels. At the lowest soil moisture level (25% field capacity), rhizobacterial isolate Pseudomonas fluorescens biotype G (ACC-5) was found to be more promising compared with the other isolates, as it caused maximum increases in fresh weight, dry weight, root length, shoot length, number of leaves per plant, and water use efficiency on fresh and dry weight basis (45, 150, 92, 45, 140, 46, and 147%, respectively) compared with respective uninoculated controls. It is highly likely that rhizobacteria containing ACC deaminase might have decreased the drought-stress induced ethylene in inoculated plants, which resulted in better growth of plants even at low moisture levels. Therefore, inoculation with rhizobacteria containing ACC deaminase could be helpful in eliminating the inhibitory effects of drought stress on the growth of peas.

Growth, Dry Matter Partitioning and Photosynthesis in North American Ginseng Seedlings

  • Proctor, John T.A.;Palmer, John W.;Follett, John M.
    • Journal of Ginseng Research
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    • 제34권3호
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    • pp.175-182
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    • 2010
  • North American ginseng seedlings (Panax quinquefolius L.) were grown in pots in heated greenhouses, in a cool greenhouse, or in the field, in 11 experiments at various times over 16 years. Crop establishment, dry matter partitioning, photosynthesis, radiation use efficiency and carbon budget were measured and/or calculated in some years. Once the seedling canopy, of about $20\;cm^2$ per seedling, and a leaf area index of 0.37, was established, about 40 days after germination, full canopy display lasted about 87 days. Only 16.6% of the incoming solar radiation was intercepted by the crop, the remainder falling on the mulched soil surface. Total and root dry matter accumulations in the cool greenhouse and in the field were about double that in the heated greenhouses. Partitioning of dry matter to roots (economic yield or harvest index) in the cool greenhouse and in the field was 73% whereas it was 62.5% in the heated greenhouses. The relationship between root dry matter and radiation interception during the full canopy period was linear with growth efficiencies of $2.92\;mg\;MJ^{-1}$ at 4.8% of incoming radiation and $0.30\;mg\;MJ^{-1}$ at 68% of incoming radiation. A photosynthetic rate of $0.39\;g\;m^{-2}\;h^{-1}$ was attained at light saturation of about $150\;{\mu}mol\;m^{-2}\;s^{-1}$ (7.5% of full sunlight); dark respiration was $0.03\;g\;m^{-2}\;h^{-1}$, about 8.5% of maximum assimilation rate. Estimates of dry matter accumulation by growth analysis and by $CO_2$ uptake were similar, 6.21 vs. 7.62 mg $CO_2$, despite several assumptions in $CO_2$ uptake calculations.

고추의 생장에 미치는 Azospirillum brasilense 및 Methylobacterium oryzae 접종 효과 (Effect of Inoculation of Azospirillum brasilense and Methylobacterium oryzae on the Growth of Red Pepper Plant)

  • 김병호;사동민;정종배
    • 한국환경농학회지
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    • 제30권2호
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    • pp.223-228
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    • 2011
  • BACKGROUND: Rhizosphere bacteria may improve plant growth and productivity both by supply nutrients and hormonal stimulation. Although many experiments have shown improvements in plant growth with inoculation of bacterial cultures to the rhizosphere, the main obstacle in the applications of plant growth promoting rhizobacteria in a large scale is the inconsistency of the results. We tested the growth promoting effects of Azospirillum and Methylobacterium strains on red pepper plant. METHODS AND RESULTS: Red pepper seedlings were grown for 25 days in a growth media inoculated with A. brasilense CW903 or M. oryzae CBMB20. The seedlings were transplanted and grown for 45 days in pots with soil in a greenhouse, at half the recommended level of fertilizer. Bacterial culture, $4.0{\times}10^9$ for A. brasilense CW903 and $5.8{\times}10^8$ CFU for M. oryzae CBMB20, was applied in root zone soil periodically every 10 days during the experiment. Inoculation of M. oryzae CBMB20 significantly increased the red pepper plant growth in terms of leaf number, height and mass of shoot, or root mass compared to uninoculated control plants. Although beneficial effects of A. brasilense on plant growth of many crops were observed, the growthpromoting effect of A. brasilense CW903 on red pepper plant was not found in this study. CONCLUSION(s): The factors responsible for the irregularities in plant growth promoting of rhizobacteria are difficult to elucidate. Extensive inoculation experiments in the greenhouse and in the field should enable us to define the factors critical to obtain successful application of plant growth promoting rhizobacteria.

실내 습도조건이 가는쇠고사리, 석위의 생육에 미치는 영향 (Effects of Indoor Relative Humidity Conditions on the Growth of Arachniodes aristata and Pyrrosia lingua in Native Ferns)

  • 방광자;주진희
    • 한국환경복원기술학회지
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    • 제5권2호
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    • pp.34-38
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    • 2002
  • 자생 양치식물중 실내식물로서 개발가치가 높은 가는쇠고사리(Arachniodes aristata )와 석위(Pyrrosia lingua)의 실내 습도조건에 따른 생육 반응을 살펴보고자 수행하였으며, 그 결과는 다음과 같다. 1. 가는고사리와 석위는 상대습도 50%, 90% 보다 25%와 같은 저습도시 식물체내수분함량, 엽록소함량, 관상가치가 저하되었다. 2. 상대습도에 대한 용토별 생육에 있어 고습도인 90%일시 용토별 생육에는 큰 차이가 나타나지 않았으나, 중습도인 50%일 경우 일반 토양이 가장 좋은 것으로 나타났다. 저습도인 25%의 경우 가는쇠고사리는 인공배합토에서, 석위는 일반토양에서 생육이 좋은 것으로 나타났다.