• Title/Summary/Keyword: standing stock

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Comparative Analysis of Forest Fire Danger Rating on the Forest Characteristics of Thinning Area and Non-thinning Area (숲 가꾸기 실행 및 미 실행지의 임분특성에 따른 산불위험성 비교분석)

  • Lee, Si-Young;Lee, Myung-Woog
    • Fire Science and Engineering
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    • v.21 no.4
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    • pp.52-58
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    • 2007
  • The effect of stand-growing-stock characteristics of thinning area and non-thinning area on forest fire was studied in this work. 14 spots were selected from 3 counties such as Yangyang, Injae, and Gapyeong and on-the-spot investigations were performed to evaluate the effect of forest fire. The stand-growing-stock characteristics on the spots were analyzed through the height of tree, breast height diameter, clear length, mortality of branch, forest tree standing crop density, degree of closure, and shrub and grass cover degree. The relation between forest fire and the risk of spread of forest fire were analyzed from the analysis of the stand-growing-stock characteristics. It is considered from this work that the possibility of forest fire is decreased on the thinning area compared to the non-thinning area because of higher clearlength, lower number of tree, lower mortality of branch and higher shrub and grass cover degree.

Preliminary Diagnosis for Pulsing Simulation of Low Trophic Ecosystem by Environmental Changes in Coastal Area (연안해역의 환경변화에 따른 저차 생태계 Pulsing Simulation 예비 진단)

  • Lee, Dae-In
    • Journal of Environmental Impact Assessment
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    • v.21 no.3
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    • pp.461-468
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    • 2012
  • In general, long-term changes of ecological factors take a pulse form in which they interact with other factors and go through a repeated increasing and decreasing cycle. The coupling of the two approaches the grid model and the box model in ecological modeling can lead to an in-depth understanding of the environment. The study analyzes temporal variations of major storages with an energy system model that formulizes effectively the relationships among nutrients, phytoplankton, and zooplankton in the Yellow Sea and the East China Sea. An increase of light intensity and standing stock of nutrient increase the magnitude and frequency of pulsing. Also, an immense reduction of nutrient concentration can cause extinction of the pulsing and bring about a steady state. It is concluded that the nutrient loads in freshwater discharge from the Yangtze affect the cycles of major ecological components as well as water quality variables and play an important role in the marine ecosystem.

Estimation of Transport and the Mass Balance of a Molecular Marker (DSBP) in Tokyo Bay Using an Ecological Model (생태계 모델을 이용한 동경만 Molecular Marker(DSBP)의 거동 에측 및 물질수지 선정)

  • Kim, Dong-Myung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.2
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    • pp.167-172
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    • 2011
  • A three-dimensional ecological model (EMT-3D) was applied to Tokyo Bay to simulate 4,4'-bis (2-sulfostyryl)biphenyl (DSBP). The simulated results were in good agreement with the observed values, with a correlation coefficient of R=0.8431 and a coefficient of determination of $R^2$=0.7108. The sensitivity analysis indicated that the photolysis rate is the most important factor. Therefore, the parameters must be considered carefully in modeling. The mass balance results showed that the standing stock of DSBP in water and in particulate organic carbon was 621.2 and 19.5 kg, respectively, and the effluent flux to the open sea was 2.63 and 0.055 kg/day, respectively.

Oogenesis and Reproductive Cycle of the Female Manila Clam, Ruditapes philippinarum in Komso Bay, Korea

  • Chung, Ee-Yung;Hur, Sung-Bum;Park, Ki-Ho
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.05a
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    • pp.580-582
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    • 2001
  • The Manila clam, Ruditapes philippinaMm (Pelecypoda: Veneridae) is present along the coasts of Korea, China and Japan. In particular, Recently, due to reclamation of tidal areas along the west coast, marine pollution, and reckless overharvesting of this clam, its standing stock has reduced for a decade. Therefore, it is necessary to manage the population of the clam with a proper fishing regime that will maintain an optimal population size in aqua farm. (omitted)

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Recent Development in Multi-national Marine Ecosystem Surveys along the Antarctic Peninsula

  • Kim, Su-Am
    • Ocean and Polar Research
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    • v.23 no.4
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    • pp.425-431
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    • 2001
  • From an ecological point of view, the western part of the Atlantic sector is one of the most productive areas in the Southern Ocean. Antarctic krill (Euphausia superba) and krill-dependent predators such as fish, seals, and birds are abundant there, and most krill fisheries have operated in this area since 1970s. The hottest issues for the proper management of krill resources nowadays are to determine total biomass in this area, and to identify environmental forces controlling stock fluctuation. This paper reviews and collates information on ongoing oceanographic activities in the Antarctic Peninsula region concerning these issues. To delineate the status and function of Antarctic krill population in Antarctic marine ecosystems, multinational researches along the Antarctic Peninsula area have been developing recently. Four member states of CCAMLR (Japan, Russia, UK, and USA) had conducted acoustic surveys in January-February 2000 (socalled CCAMLR-2000 survey), and krill standing stock at 120 kHz was estimated to be 44.29 million metric tonnes in the western Atlantic sector of the Southern Ocean. On the other hand, the Southern Ocean GLOBEC (SO-GLOBEC) Programme has prepared a serial winter survey to examine the factors that govern krill survivorship and distribution in relation to shelf circulation processes. Ship-based surveys using ice-breakers are being conducted by three nations (Germany, UK, and USA) around the Marguerite Bay during the austral fall and winter 2001 and 2002. In addition to these two large-scale surveys, some CCAMLR members have carried out joint oceanographic surveys near the South Shetland Islands to detect ecosystem changes since 1994. Especially from December 1999 to February 2000, in conjunction with CCAMLR-2000 survey, four nations (Japan, Korea, Peru, and USA) conducted acoustic surveys to produce time-series information on krill distribution and biomass near the South Shetland areas. Though the aims of each program and the approach to solve the scientific questions were different each other, the results from each program fill the gaps between programs. Further cooperation and exchange in these activities could be beneficial to each program.

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SEASONAL CHANGES IN ABUNDANCE AND COMPOSITION OF DIATOMS IN THE SUYUNG BAY, PUSAN (수영만에 있어서의 규조류의 계절적인 양 및 조성변화)

  • CHOE Jung Shin
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.2 no.1
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    • pp.16-24
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    • 1969
  • The present paper deals with the seasonal changes in abundance and composition of diatoms in the Suyung Bay, Pusan, Korea. This study was carried out from August 1966 through July 1967 As a result of the present study, 123 species of diatoms were Identified. While the highest number of diatoms (2,554,000 cells per liter) was recorded in April of 1967, the lowest number (20,400 cells per liter) appeared in December of 1966. In genera the standing stock of diatoms was high in spring and early fall and was low in late fall and winter. Two genera of the diatoms, Chaetoceros and Skeletonema, occupied a great portion of the diatom population throughout the course of this study. The following genera also appeared abundantly: Asterionella, Eucompia, Leptocylindrus and Nitzschia.

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Occurrence of Modern Planktonic Foraminiferal Species and their Seasonal Variations around Jeju Island, Korea (제주근해에 출현하는 현생 부유성 유공충 종과 계절변화)

  • Hyun, Sangmin;Kimoto, Katsunori;Cho, Sung-Hwan
    • Ocean and Polar Research
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    • v.35 no.2
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    • pp.181-191
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    • 2013
  • To investigate the occurrence of modern living planktonic foraminiferal species and their seasonal variations around Jeju Island, we conducted planktonic foraminiferal sampling at KIOST's regular sampling sites during 16 months. In total seven genus and 16 modern planktonic foraminiferal species were identified with six dominant species. Dominant species were Gloigerinoides sacculifer, Globigerinoides ruber, Globigerina bulloides, Noegloboquadrina dutertrei, Pulleniatina obliquiloculata, and Globorotalia inflata. Most of the species were characterized as being typical subtropical species and showed seasonal variations and/or intermittent occurrence from season to season. The occurrence of living foraminifera revealed a strong relationship with water temperature, but not with salinity. Species succession seems to occur along with water temperature changes. Some patch distribution and water temperature dependences appear to be significant since there is a high degree of variation in the occurrence patterns of species and standing stock. More detailed quantitative study is necessary to confirm the species diversity and seasonal variations of planktonic foraminifera and related ocean environmental changes.

A Study on State of Boundary Barriers Resources in Rural Villages (농촌마을 담장자원 조사연구)

  • Lim, Jong-Hyeon;Choi, Soo-Myung;Cho, Joong-Hyun
    • Journal of Korean Society of Rural Planning
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    • v.18 no.1
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    • pp.17-28
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    • 2012
  • Functional mismatch and thought and plan-less material use of recently built boundary barriers in rural areas should greatly degrade their amenity value as one of linear villagescapes, but, their present state-of-art basically necessary for problem-solving had never surveyed up to now. From this point of view, this study tried to investigate present stock quantities and qualities of boundary barriers in rural areas by sample studies on 21 case villages(7 types ${\times}$ 3 cases) and comparative analysis between the planned or improved and nots. Wall type was absolutely dominated in the structural terms, of which more than half was used cement block as building material and, therefore, grey-colored. More than half of total barrier length were fully shielded, while relatively partially shielded in the mountainous villages in open space and 'Cultural villages' with closed housing structures. Free standing style of barriers was shown along over two thirds of their total length, although not more than half in planned reclaimed villages. Especially, because of one-sided wall type structure, mismatched over-shieldness and poorer maintenance condition of the boundary barriers in peri-urban villages, there should be provided with very intensive improvement efforts for amenity barriers.

Lentivirus-mediated Gene Transfer to Bovine Embryos

  • Kim, Young-Mi;Kwon, Mo-Sun;Koo, Bon-Chul;Kim, Teo-An;Yom, Heng-Cherl;Ko, Dae-Hwan
    • Reproductive and Developmental Biology
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    • v.32 no.1
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    • pp.15-20
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    • 2008
  • Pronuclear DNA microinjection has been the most universal method in transgenic animal production but its success rate of transgenesis in mammals are extremely low. To address this long-standing problem, we used retrovirus- and lentivirus-based vectors carrying the enhanced green fluorescent protein (EGFP) gene under the control of ubiquitously active cytomegalovirus (CMV) promoter to deliver transgenes to bovine embryos. The rate of transgenesis was evaluated by counting EGFP positive blastocysts after injection of concentrated virus stock into the perivitelline space of the bovine oocytes in metaphase II. Among two different types of lentivirus vectors derived from FIV (feline immunodeficiency virus) and HIV (human immunodeficiency virus), the former scored the higher gene transfer efficiency; almost 100% of the blastocysts developed from the oocytes infected with FIV-based vector were EGFP positive. As for the vectors derived Com HIV lentivirus, the transgenesis rate of the blastocysts was reduced to 39%.

Permanent Tracheostomy in a Thoroughbred Mare with Arytenoid Chondritis

  • Park, Soomin;Park, Kyung-won;Lee, Eun-bee;Sohn, Yongwoo;Jeong, Hyohoon;Kang, Tae-Young;Seo, Jong-pil
    • Journal of Veterinary Clinics
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    • v.38 no.5
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    • pp.244-248
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    • 2021
  • A 10-year-old Thoroughbred mare was referred to the Jeju National University Equine Hospital with roaring, dyspnea, and weight loss. On endoscopic examination, the horse was diagnosed with right arytenoid chondritis. Surgical treatment was selected due to the failure of a previous medical treatment. Permanent tracheostomy was performed in a standing position. The horse was restrained and tied in a proper position in the stock. The cranial parts of the 2nd to 5th tracheal cartilages were resected, as were the associated skin, mucosa, muscle, and cartilages. After the stoma was formed, external mucosa and skin were sutured using a simple interrupted method. The horse was hospitalized for 22 days receiving postoperative care including antibiotics, non-steroidal anti-inflammatory drugs, dressing as required, and was pregnant six months after the surgery. A permanent tracheostomy is thought to be effective in horses with diseases causing upper respiratory tract obstruction.