• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.360-363
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• 2006

The red tide related with Cochlodinium Polykrikoides bloom has been frequently occurred around the South Sea of Korea and caused the economic loss in the coastal breeding grounds. The outbreak scale was usually change by physical, biological and environmental condition at each years. Relatively large-scale red tide occurred in 1995, 1997, 1999, 2001, 2002 and 2003 through spatial scale, duration and maximum density. Compared the scale of red tide with physical condition around the South Sea, the lower coastal temperature on August around the South Sea corresponded with the large scale red tide. By serial oceanographic investigations on August in the South Sea and estimated wide area temperature information by satellite, SSTA around the South Sea and wide area was negative when the outbreak of red tide was large scale. From the results of temperature difference between surface and 30m layers, the occurrence of enormous red tide has a tendency when the temperature gradient around the seasonal thermocline was weakened. Larger Kuroshio volume transport in the upstream was also corresponded with the large scale red tide.

• Asian-Australasian Journal of Animal Sciences
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• 제13권8호
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• pp.1162-1172
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• 2000

The research was conducted to quantify farm and household characteristics of sheep farmers, evaluate farmer access to and the effectiveness of livestock services in sheep farming areas, and examine regional constraints to improving sheep productivity and profitability in Nepal. A rapid diagnostic socioeconomic survey of 200 sheep farmers was carried out in 1996 and all four ecological regions (Trans-Himalayan, Mountains, Hills and Terai), each with a distinct local sheep breed, were represented in the survey. Six major constraints were identified: (a) poor performance of local sheep breeds, (b) a serious seasonal deficit of pasture and other feed, (c) the lack of an organized market for wool and meat, (d) poor access to agricultural credit, (e) primitive shearing equipment, and (f) an inadequate supply of drinking water for sheep. Strategies to assist farmers develop their sheep management skills, improve access and quality of support services, improved technology adaptable to local conditions and effective linkages with local carpet and meat industry are likely to overcome the constraints and alleviate persistent poverty faced by sheep farmers in Nepal.

• 한국가축번식학회지
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• 제15권3호
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• pp.207-220
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• 1991

This study was carried out to investigate the ultrastructural changes of ooplasm and follicular membrane of oocytes, obtained from 150 of 3-year-old female rainbow trout(Oncorhynchus mykiss). All data were collected from March in 1989 to February in 1990, and from August to October in 1991. The size of the nucleoli and number of the yolk granules increased as the oocyte growed. Yolk granules were deposited in the oocyte as crystalline granules. Due to the presence of large early and late maturing oocytes, their ovaires were enlarged, transparent and granular. The lattice was broken down at hydration, leaving the egg transparent. As thepercentages of fish in LPO and EMO stage increased from September to October, Mean GSI values increased. Follicle cells such as granulosa cell and thecal cell change a squamous into cuboid shape in LPO and EMO stage. Seasonal changes in the microscopic appearance of the ovaries were well correlated with those in bothgonadosomatic index and macroscopic apearance. Under the natural conditions,t he ovarian follicle influences the histological development and periodical secretion of the hormones, sufficient for a oogenesis and gonadal steroid production. The electrophoretic pattern of major band in mature stage was much thicker(70∼110k dalton) than that in previtellogenic phase.

• 한국가축번식학회지
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• 제16권3호
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• pp.247-260
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• 1992

This study was carried out to investigate the histomorphological changes of ovaries obtained from 100 of 1-year-old female Korean loach(misgurnus anguillicaudatus). The light microscopic and ultrastructural changes ofooplasm and follicular membranes of oocytes, were observed by lightand transmission electron microscope during the reproductive cycle. All data were collected from November in 1991 to May in 1992. The results obtained in this study were as follows: The size of the nucleoli and number of the yolk granules increased as the oocytes grown. Yolk granules were loosely deposited in the oocytes as crystalline granules. Due to the presence of large early and late maturing oocytes, their ovaries were enlarged, transparent, granular and yellowish in color. The lattice was broken down at hydration, leaving the egg transparent. As the percentages of fish in LMO and RO stage increased from March to April, mean gonadosomatic index(GSI) values(18.49%) increased. Zona radiata change a squamous into cuboid shape in EMO stage. Processes from the granulosa cells and from the oocyte, microvilli grow and make contact with other in the pore canals of the zona radiata during vitellogenesis, but are withdrawn as the zona radiata becomes more compact and devoid of pore canals during oocyte maturation. Seasonal changes in the microscopic appearance of the ovaries were well correlated with those in both GSI and macroscopic appearance.

• Animal cells and systems
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• 제16권3호
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• pp.260-267
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• 2012

Calling behavior is often used to infer breeding patterns in anurans. We studied the seasonal and diel calling activities of anuran species in a wetland in central Korea to determine the calling season and to evaluate the effects of abiotic factors on male calling. Acoustic monitoring was used in which frog calls were recorded for a full day, once a week, throughout an entire year. Using acoustic monitoring, we identified three frog species in the study site. Males of Rana dybowskii called in late winter and early spring; we thus classified this species as a winter/spring caller. The results of binary logistic regression showed that temperature, relative humidity, and 1-day lag rainfall were significant factors for male calling in R. dybowskii. Temperature and relative humidity were important factors for the calling activity of R. nigromaculata, whereas 24-h rainfall and 1-day lag rainfall were not significant. Thus, we determined R. nigromaculata to be a summer caller independent of weather. In Hyla japonica, relative humidity, 24-h rainfall, and 1- day lag rainfall were significant for male calling, suggesting that this species is a summer caller dependent on local rain.

• 한국잠사곤충학회지
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• 제50권1호
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• pp.10-14
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• 2012

야생 뽕나무의 자원화 및 이용기술을 개발하기 위해 강원도 원주, 인제, 양양 3개 지역에서 생육 단계별로 채취한 야생 뽕나무의 뽕잎을 대상으로 레스베라트롤 함량을 분석함으로써 뽕 품종의 육종 효율을 높이는 동시에 기능성 및 이용 효율이 기대되는 뽕 유전자원을 선발하고자 하였다. 야생 뽕잎의 레스베라트롤 함량은 오디에 비해 평균 함량이 상당히 낮았으나 장려뽕에 비해서는 높은 경향을 나타냈다. 생육시기별 야생 뽕잎의 평균 레스베라트롤 함량은 추기의 뽕잎이 춘기보다 함량이 높았다. 즉 춘기 5개엽기 어린잎의 평균 레스베라트롤 함량은 $344{\mu}g$/100 g이었으며 뽕잎의 생육시기가 경과함에 따라 $356{\mu}g$/100 g DW, $273{\mu}g$/100 g DW, $253{\mu}g$/100 g DW 이었다. 추기 뽕잎의 레스베라트롤 함량은 시기가 경과함에 따라 $438{\mu}g$/100 g DW, $476{\mu}g$/100 g DW, $598{\mu}g$/100 g DW로 증가하였다. 따라서 레스베라트롤의 원료로서 뽕잎을 이용하고자 하는 경우 봄뽕보다는 가을뽕을 이용하는 것이 바람직하며, 수세 후 바로 실온에 음건하여 사용하는 방법이 레스베라트롤의 함량이 높을 것으로 판단되었다. 원주 지역의 No. 3 개체의 야생 뽕잎은 생육시기 모두 평균 함량보다 높았으며 전체 평균 $539{\mu}g$/100 g DW으로서 10개체의 뽕나무 중 가장 높은 함량을 나타냈다. 다음으로 인제 지역의 No. 7 개체의 뽕잎은 전체 평균 $491{\mu}g$/100 g DW으로 높았다. 따라서 두 개체의 뽕나무는 레스베라트롤 함량이 높은 육종소재 및 이용 가능성을 검토할 만한 자원으로 선발하였다.

• 한국환경생태학회지
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• 제33권6호
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• pp.645-653
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• 2019

본 연구는 경기도 안산시 상록구에 위치한 인공 습지인 안산갈대습지에 서식하는 침입외래종 붉은귀거북(Trachemys scripta elegans)의 활동에 영향을 미치는 요인과 시기별 활동의 차이를 파악하기 위해 실시되었다. 연구 지역 내에 총 9개의 그물을 설치하여 2013년 4월 28일부터 9월 28일까지 154일간 총 308회 확인하였으며, 연구 기간 중 총 60개체(미성숙 12개체, 수컷 26개체, 암컷 22개체)를 96회에 걸쳐 포획하였다. 활동 요인 분석을 위해 붉은귀거북의 일별 포획량을 활동량으로 간주하고, 총 12개의 환경적 요인에 대하여 다중 회귀 분석을 실시하였다. 연구 결과, 환경 요인 중 일장(daylength)이 붉은귀거북의 활동에 유의한 영향을 미치는 것으로 확인되었으며(multiple regression analysis, p<0.001), 기타 환경적 요인들은 유의한 영향을 미치지 않는 것으로 나타났다. 그리고 붉은귀거북의 활동이 가장 활발해지는 시기는 번식이 시작되는 5월 하순으로 확인되었으며 번식기 동안의 일장이 다른 시기의 일장과 유의한 차이를 보였다(Kruskal-Wallis test, p<0.001). 이렇게 확보된 서식지 내 환경 요인과 종과의 관계에 대한 정보는 향후 침입외래종의 관리방안 마련에 기여할 수 있을 것으로 생각된다.

• Journal of Ginseng Research
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• 제20권4호
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• pp.472-500
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• 1996

Researches on mineral nutrition, physiology and phyrsiological diseases, . cultivaction methods. brceding. pest control quality management and extension during 1976-1995 in Korea were reviewed Review in brceding and pest control was restricted to the researches directely related to cultivaction. Mineral nulrient up take. partion and varicos factors such as top dreasing. Light intersity etc. and interrelationship between minerals were investigated. Top dressing was not effective due to low minera1 requorement Physiological characteristics on tempelature light and water were well elucidated and applied to assess traditional cultivation method and its inovation. Photosyrnthetic pigments. light harvest proteins and activity of related enzymes were studied. In nitrogen metabolism arginine, praline, ammonium, threonine appeared to have important role in re growth of shoot Saponin metabolism was studied in relation to growth and new ginsenosides were found but physiological role of saponin was not clearly elucidated yet Endogenous growth regulators were reported and various erogenous growth regulators were studied for growth stimulation. short stem and seed pruning etc. Various physiological diseases were investigated for cause and control measures were established. Water culture was little studied Forest culture was studied but not retched the recommendable stage Drip irrigation straw mulching. seasonal shading and soil preparation method including soil fertility adjustment were established for practical application. Shading materials completely changed to polyethylene net and materials of polymers The research on ginseng cultivation in paddy field opened the way to establish the permanent ginseng cultivation plantation Ginseng harvester and seeder were developed in the late 1950s. Transplanted and many other machines were developed in the early 1990s. In ginseng breeding only pure line selection was of practical significance several verities were at the stage of seed propagation at ginseng plantations. Mutation breeding (${\gamma}$-ray. X-ray chemicals) was not successful. The research on plantlet formation through tissue culture was a little progressed but still far behind to vegetative propagation. Disease control research was concentrated in the isolation and identification of pathogans. their ecological charactelistics and biological control and soil humigation. Potato root rot nematodes was found and control method was established. Insect and small animal control research was greatly progresses in identification, ecological investigation, and ecological and physical control. Weed control was less important due to the development of mulching method of ridge and ditch. Quality factors of raw ginseng in relation to red ginseng process were extensively studied. Traditional quality measures were elucidated in accordance with modern analytical chemistry resulting in the importance of peptides in the centrat part rather than ginsenosides For large root production growth promoting rootzone micrcorganisms (PGPRM) were isolated and active compounds were identified. Field test on PGPRM was on going. Varictus methods formality improvement through cultivation were developed. Management research of ginseng production was rare Extension was active throuch official and private organizations and through workshop for the extension specialists, and direct lectures to grower's. Extension services made the researcher to understand the existing problems at grower's fields. Research environment for ginseng production was in prime time only for three years when Korea Ginseng Research Institute was established then gradually aggravated.

• 한국환경생태학회지
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• 제30권6호
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• pp.977-985
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• 2016

환경부 지정 멸종위기 II급 종인 남생이의 복원을 위하여 개체증식 프로그램들을 개발해왔지만, 남생이의 번식생리에 대한 이해는 여전히 부족한 상태이다. 본 연구에서는 2014년 11월부터 2015년 10월 사이에 동면을 한 개체와 동면을 하지 않은 개체를 이용하여 성호르몬, 여포와 알의 수와 크기, 암 수간의 행동상호작용의 계절적 변화를 연구하였다. 비록 동면 여부에 따라 다소의 편차는 있었지만, 암컷의 혈청 에스트라디올 농도는 7월부터 증가하기 시작하여 8월-10월에 최고 농도를 보였으며, 수컷의 테스토스테론의 농도는 8-9월에 최고 농도를 보였으며, 3월에 가장 낮았다. 동면을 한 암컷들은 5월초에서 7월 중순 사이에 완전히 발달한 알을 가지고 있었으며, 산란은 6월 초순부터 7월 하순 사이에 이루어졌다. 반면, 동면을 하지 않은 암컷들은 이른 4월부터 이른 6월 사이와 8월 중순에서 11월 하순 사이에 알을 가지고 있었으며, 산란은 6월초, 10월 중순, 2월 초에 이루어졌다. 이러한 결과는 동면이 여포와 알의 정상적인 발달에 매우 중요한 역할을 함을 보여준다. 행동연구에서 암 수간의 구애행동을 포함하는 행동상호작용은 8월 하순부터 증가되어 10-11월에 최대를 보였다. 연구결과는 남생이의 짝짓기 기간이 성호르몬의 증가와 직접 연계되어 있지만, 여포와 알의 발달은 그렇지 않다는 것을 보여준다. 이러한 연구결과는 멸종위기종인 남생이의 성공적인 번식프로그램을 운영하는데 매우 중요하게 사용될 것으로 판단된다.

• 원예과학기술지
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• 제17권1호
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• pp.11-14
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• 1999

참다래 및 야생다래에서 수액 채취시기에 따른 수액특성, 수액내 유리당, 무기물 및 아미노산함량 변화를 조사하였다. 참다래 및 야생다래에서 수액 채취시기에 따른 수액량은 채취 시기가 늦을수록 심하게 감소하는 경향을 보였다. 수액내 수분함량, 당도, 점도 및 pH는 두 종간 차이가 없었으나 산함량 및 탁도는 야생다래보다는 참다래에서 다소 높은 경향을 보였다. 당은 참다래에서 fructose, glucose, sucrose, galactose, manitol이 함유되어 있었고 야생다래에서는 fructose, glucose가 함유되어 있었는데 당의 대부분은 fructose였다. 수액내 주요 무기물은 칼슘, 카리 및 마그네슘으로 칼슘함량이 상대적으로 가장 높았다. 두 종에서 각각 17종의 아미노산이 함유되어 있었는데 이들중 주요 아미노산은 glutamic acid, lysine 및 isoleucine이었는데 이중 glutamic acid함량이 가장 높았다. 참다래에서 histidine, methionine과 tylosine을 제외한 나머지 성분은 야생다래에 비해 높았다. 무기물 및 아미노산함량은 수액 채취시기가 늦을수록 증가하는 반면 유리당함량은 감소하는 경향을 보였다. 수액의 품질은 채취시기가 늦을수록 향상되는 것으로 나타났으나 수액채취량은 현저히 감소하는 경향을 보였다.