• Title/Summary/Keyword: Bamboo net

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PRELIMINARY TEST ON THE CREEL HOLDING OF THE ANCHOVY, ENGRAULIS JAPONICA (멸치 축양의 예비시험)

  • RARK Sing Won;LEE Byoung Gee;SU Young Tae;SON Boo Il;KIM Moo Sang
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.5 no.2
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    • pp.63-67
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    • 1972
  • Preliminary creel-holding test of live anchovies which are to be used as bait for the skipjact fishery, was conducted on the fish caught by set net and lift net. They were held in the creels constructed with bamboo frame and minnow netting, during the period of Oct. 24-Nov. 28 in 1972. If was found that the survival rate of the creel-held anchovies varied by the size of fish, the towed distance and speed of fish-carrying creel in which the fish were accomodated after catchi. 1. The survival rate of the medium size anchovies, 7.8-9.6cm in length and 4.6-4.8 g in weight, was $70-92\%$ during the holding period of 20-35 days. Whereas, only $16\%$ of juvenile anchovies, 5.3cm in length and 1.0 g in weight, were survived for 19 hours after catch. 2. During the time of transport, the farther and faster the creel containing fish were towed, the less fish were survived in the subsequent holding period. 3. Though both the set net and lift net could be fairly used to catch live anchovy, no decision between these two gears could be made in this experiment to determine the superiorness for the subsequent survival rate.

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Fishing Mechanism of Pots and their Modification 3. Behavior of Conger Eel, Astroconger myriaster, to Net Pots (통발어구의 어획기구 및 개량에 관한 연구 3. 그물통발유에 대한 붕장어의 행동)

  • KIM Dae-An;KO Kwan-Soh
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.23 no.3
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    • pp.238-244
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    • 1990
  • The behavior of conger eel, Astroconger myriaste(Brevoort), to the net pots with baits was investigated alternately in two experimental water tanks. One of the pots being dropped on the tank bottom, the eels increased rapidly in number of touching the pot to show a maximum whithin 30 minutes and then decreased gradually. The enterings of eels into the pots were also made mainly within 30 minutes and easier in pots with lower entrances. But the complete enterings were decided by the passage of eel tails through the pot entrances and so the eels retreated frequently after attemping to enter the pots, especially in pots small in the interval between the entrances and the baits or in pots with flappers. However, most of enterings encouraged the touches and earlier enterings ascribed earlier production of maximum touch. The eels, if entered the pots without flappers, got out of the pots relatively easily and the getting-out was easier in pots with lower entrances. On the other hand, the eels entered the pot with flappers could not get out of the pots. A comparison between the circular and square pots gave that the guidance of eels to the entrances was easier in the former and the passing of eels through the entrances in the latter, not only at the inside of pots but also at the outside. The general behavior of eels in touching or entering the net pots in the above results was almost equal to that on the bamboo and plastic pots in the previous paper.

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Fishing Mechanism of Pots and their Modification 5. An Experiment for Modifying the Pot for Conger Eel, Astroconger myriaster (통발어구의 어획기구 및 개량에 관한 연구 5. 붕장어통발의 개량실험)

  • KIM Dae-An;KO Kwan-Soh
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.23 no.4
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    • pp.315-322
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    • 1990
  • In order to find out the most favorable shape and structure of pot for conger eel, Astroconger myriaster(Brevoort), the box type, tube type and flat box type of net pots and the pipe type of plastic pot were prepared. Then, the ability of the pots attracting the eel into them were investigated through a tank experiment. The attracting ability was highest in the pipe type without distinction of its length, 50cm and 60cm. In the flat box type, the effective height of pot and the diameter of entrance tip turned out 5cm respectively. But the ability was very poor in the rest pots, especially in the tube type. Thus, the pipe type and flat box type of pots were employed again in a field experiment for comparing their catches with those of the conventional bamboo and plastic pots. In the experiment, the catches were the most in the pipe type and second in the flat box type. But the bamboo and plastic pots both produced comparatively low catches, showing no significant difference between them. It was therefore concluded that the pipe type of pot might be the most favorable one for catching the conger eel.

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Significance of Aspect and Understory Type to Leaf Litter Redistribution in a Temperate Hardwood Forest

  • Lee, Do-Won;Yoo, Ga-Young;Oh, Sung-Jin;Shim, Jee H.;Kang, Sin-Kyu
    • Animal cells and systems
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    • v.3 no.2
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    • pp.143-147
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    • 1999
  • Annual production and redistribution of leaf litter were compared among three distinct understory patches in a temperate hardwood forest dominated by Quercus mongolica, Kalopanax pictus, Acer pseudo-sieboldianum, and Carpinus cordata. Two patches were located on a southwest-facing slope: one with an understory dominated by herbaceous plants (Patch S), and the other covered with evergreen dwarf bamboo, Sasa borealis (patch SS). The third patch was on the opposite slope with an understory dominated by herbaceous plants (Patch N). Annual leaf litterfall was averaged 330 g m$^{-2} yr$^{-2}$ in the three patches from 1994 to 1998. From mid-September 1996 to mid-September 1997, net transport of leaf litter over patch bound-aries was 1,824g m$^{-1}$ from Patch S to SS, 1,465g m$^{-1}$ from Patch S to N, and 886 g m$^{-1}$ from Patch SS to N. The amounts moving downslope out of Patch S, SS, and N were 2,548, 471, and 588g m$^{-1}$, respectively. When a mass balance approach was employed for the data of leaf litter transport, the results were relatively consistent with 216, 631, and 724g m$^{-2}$ of leaf litter stores in Patch S, SS, and N, respectively, in April 1997. This study suggests that leaf litter redistribution is largely regulated by aspect and understory type and exerts a significant effect on carbon processes in the forest ecosystem.

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Current status on Miscanthus for biomass (바이오매스로서의 억새에 대한 연구 동향)

  • Seo, Sang-Gyu;Lee, Jeong-Eun;Jeon, Seo-Bum;Lee, Byung-Hyun;Koo, Bon-Cheol;Suh, Sae-Jung;Kim, Sun-Hyung
    • Journal of Plant Biotechnology
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    • v.36 no.4
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    • pp.320-326
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    • 2009
  • The carbon dioxide concentration of the atmosphere is projected to increase by almost 50% over the first 50 years of this century. The major cause of this increase is continued combustion of fossil fuels. As a result, the significant changes in climate that have already occurred will be amplified, in particular a global temperature increase. Renewable energy production has a central role to play in abating net $CO_2$ emissions to a level that will arrest the development of global warming. Especially, biomass crops are becoming increasingly important as concerns grow about climate change and the need to replace carbon dioxideproducing fossil fuels with carbon-neutral renewable sources of energy. To succeed in this role, biomass crop has to grow rapidly and yield a reliable, regular harvest. A prime candidate is Miscanthus, or Asian elephant grass, a perennial species that produces over 3 metres of bamboo-like stems in a year. Miscanthus species are typically diploid or tetraploid. Hybrids between species with different ploidy levels result in the highly productive triploid hybrids, M. ${\times}$ giganteus. Here we will detail the Miscanthus characteristics desired of a biomass fuel crop.