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Long-term Changes of the Fish Fauna and Community Structure in the Jungrang Creek, Seoul, Korea (중량천의 어류상과 어류군집 구조의 장기 변동)

  • Kim, Gyeo-Bung;Kil, Hye-Kyung;Yu, Byung-Tae;Kim, Min-Young;Bae, Kyung-Seok
    • Korean Journal of Ecology and Environment
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    • v.35 no.2 s.98
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    • pp.63-70
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    • 2002
  • Long-term changes of the fish fauna and its community structure from the Jungrang Creek of the Han River system in Seoul were investigeted from 1990 to 2000. Total species occurred during the survey period were 14 species in 6 families, and total individual number was 108,366. Fishes at the Jungrang Creek had not been distributed in the 1980s and 1990 because of heavy water pollution as well as environmental damage in the riparian areas. However, Cyprinus carpio and Carassius auratus in cyprinidae were rehabitated since the early 1990s when the water quality was improved because of foundation of sewage division pipe. Species nombers gradually increased to 6 species in 1996, 9 species in 1998, and 11 species in 2000. Individual numbers rapidly increased to 164 individuals in 1996, 146 individuals in 1998, and 108,094 individuals in 2000. A large number of Cyprinus carpio and Carassius auratus, which are abundantly distributed in the main course of the Han River, were found when they migrate to the upper reaches of the Jungrang Creek for spawning. Mass fish floatings were occurred on the 21st of April and the 11th of June in 2000 due to DO depletion at the lower site (Site 4) of discharging point of Jungrang sewage treatment plant and stagnant spot(Site 3) of dammed pool. Major dominant species were Cyprinus carpio and Carassius auratus (Cyprinidae). Others dominant species were Pseudorasbora lab대 (Cyprinidae) and Silurus asotus (Siluridae). Dominance indices were relatively high (0.79 to 1.00). Species diversity andrichness indices were relatively low (0 to 1.66and 0 to 1.41, respectively). Species diversity and richness indices were slightly higher at the middle reaches (Site 2 and Site 3) than the upper reaches and the mouth of the Jungrang Creek. However, the fish fauna of the Jungrang Creek was very poor and its community structure was very simple.

PROPAGATION OF GRASS CARP AND SILVIR CARP, 1971 (초어 및 백련의 종묘 생산에 관한 연구, 1971)

  • KIM In-Bae;PAIk Eui In
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.4 no.3_4
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    • pp.113-120
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    • 1971
  • In 1971, about 150,000 fingerlings of grass and silver carps were produced and distributed from the Fishculture Laboratory of Pusan fisheries College. The adults Were those transplanted from Japan in 1963. Findings during the process of this production are summarized as following : 1. Brood fish must be handled with a great care during the catching, hormone injection and maturity inspection so as the fish are not injured, otherwise, the eggs would not mature perfectly. Scale fall also affects significantly. 2. The amount of pituitary to be injected is preferable to be 2 to 3 times or more in donor's body weight to obtain good results. 3. The eggs should be spawned or stripped and inseminated as soon as mature. If the spawning is delayed the eggs become overmature and the hatching rate decreases significantly. 4. The water once used for the incubation of eggs should not be reused. The eggs under hatching process were melted away when water once used for incubation was reused. 5. A great care must be paid to keep water in quality when the net cage culture system is employed for raising fry or early fingerlings of Chinese carps. The best method to keep water in quality is to supply water in the cage continuously through a pipe or hose. 6. Heavy outbreaks of Spirogyra occured when clear well water was supplied into the cage, and a great number of fry or fingerlings were trapped or entangled resulting in a significant decrease of fish under rearing. It was prevented when moderately bloom-ed pond water was supplied into the cage. 7. Silver carp fry are usually captured and transported in the cool season because they can not be handled in the warm season owing to a high mortality, but cage cultured small size fingerlings ranging from 1.5 to 2 cm in total length are easily handled and transported even in the hot summer season, thus it enables the fish farmers to start growing them one season earlier.

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Project of Improving Good Agriculture Practice and Income by Intergrated Agricultural Farming (미얀마 우수농산물 재배기술 전수사업)

  • Lee, Young-Cheul;Choi, Dong-Yong
    • Journal of Practical Agriculture & Fisheries Research
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    • v.16 no.1
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    • pp.193-206
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    • 2014
  • The objectives of the project are to increase farmers' income through GAP and to reduce the loss of agricultural produce, for which the Korean partner takes a role of transferring needed technologies to the project site. To accomplish the project plan, it is set to implement the project with six components: construction of buildings, installation of agricultural facilities, establishment of demonstration farms, dispatching experts, conducting training program in Korea and provision of equipments. The Project Management Committee and the Project Implementation Team are consisted of Korean experts and senior officials from Department of Agriculture, Myanmar that managed the project systematically to ensure the success of the project. The process of the project are; the ceremony of laying the foundation and commencing the construction of training center in April, 2012. The Ribbon Cutting Ceremony for the completion of GAP Training Center was successfully held under PMC (MOAI, GAPI/ARDC) arrangement in SAl, Naypyitaw on June 17, 2012. The Chairman of GAPI, Dr. Sang Mu Lee, Director General U Kyaw Win of DOA, officials and staff members from Korea and Myanmar, teachers and students from SAl attended the ceremony. The team carried out an inspection and fixing donors' plates on donated project machineries, agro-equipments, vehicles, computers and printer, furniture, tools and so forth. Demonstration farm for paddy rice, fruits and vegetables was laid out in April, 2012. Twenty nine Korean rice varieties and many Korean vegetable varieties were introduced into GAP Project farm to check the suitability of the varieties under Myanmar growing conditions. Paddy was cultivated three times in DAR and twice in SAl. In June 2012, vinyl houses were started to be constructed for raising seedlings and finished in December 2012. Fruit orchard for mango, longan and dragon fruit was established in June, 2012. Vegetables were grown until successful harvest and the harvested produce was used for panel testing and distribution in January 2013. Machineries for postharvest handling systems were imported in November 2012. Setting the washing line for vegetables were finished and the system as run for testing in June 2013. New water tanks, pine lines, pump house and electricity were set up in October 2013.

Study on Spring Cocoon Crops with the Leaf Produced in the Mulberry Field close to the Totacco Field (개량 Mulching 담배밭 부근뽕잎이 춘잠작에 미치는 영향에 관한 연구)

  • 이상풍;김정배;김계명;박광준
    • Journal of Sericultural and Entomological Science
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    • v.16 no.1
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    • pp.67-75
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    • 1974
  • The studies are to know how much cocoon crops is damaged by the stained leaf with nicotine produced from the tobacco field cultivated in mulching system in spring season and by residual nicotine in autumn season. Furthermore, the new knowledges are to make both industries keep up with their development. In spring season mulberry Held is located higher on the West-North of tobacco held below 20 degrees of slope and with 36 per cent of East-South wind and 18 per cent of South wind blowing from tobacco fold to the mulberry fold. In addition, silkworm larvae are fed with the mulberry leaf produced in the different plots placing by the different distances, l0m, 25m, 50m, 80m, and loom far from the tobacco Held as a control and it is also considered that narcotic larvae including the dead larvae are not observed. On the other hand, it is noted that better leaf quality and abundant growth of mulberry tree is produced from the mulberry fold closer to the tobacco field and with a low slope. 1) Maximum weight of larval body at the 5th stage is damaged by the stained leaf with the nicotine up to 25m far from the tobacco held. 2) The larvae fed with the mulberry leaf in mulberry Held up to 25m far from the tobacco fold produce small number of the fresh cocoons per 1 liter. 3) Low single cocoon weight and low cocoon shell weight are produced by the poison damaged larvae fed with the mulberry. leaf up to 25m far from the tobacco field and weight of cocoon shell is damaged higher than the single cocoon weight. It is resulted in low percentage of cocoon shell. 4) Cocoon yield including the double cocoon from 10,000 larvae is decreased by the larvae fed with the stained leaf in the mulberry fold up to 25m far from the tobacco fold and 19 per cent of cocoon yield is decreased with 2.4kg of cocoon yield in l0m plot and with 2.5kg of cocoon yield in 25m plot at the first season and at the 2nd season with 1.8kg o( cocoon yield in l0m plot and with 11.5kg of cocoon yield in 25m plot, 11 per cent and 9 per cent of cocoon yield including double cocoon from 10,000 larvae is decreased, as compared with the control, respectively. With these results, it is observed that nicotine damage is occurred to the silkworm larvae if the larvae are fed with the leaf in the mulberry Held within 25m-50m far from the tobacco field.

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