• Korean journal of applied entomology
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• v.51 no.4
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• pp.305-312
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• 2012

This study was conducted to elucidate the seasonal prevalence of adult mosquitoes and occurrence of anopheline larvae in Gimpo, Gyeonggi province, Republic of Korea. Sampling of adult mosquitoes was carried out 18 times from May to September in 2008, using light traps at six sites. A total of 48,919 individuals belonging to 16 species and 8 genera were collected. Aedes vexans nipponii (43%) was the most frequently collected, followed by Anopheles sinensis (34%) and Culex tritaeniorhynchus (14%). The seasonal prevalence of anopheline mosquitoes had a different occurrence compared to that of Cx. tritaeniorhynchus. Anopheline larvae were collected using a standard dipper (size = of 350 ml) at eight habitat types of 203 point locations. Anopheline larvae were confirmed from 138 points (63%). The average larval population per dipper was highest in the lotus plantation (6.9 individuals), followed by irrigation channel (4.5 ind.), dropwort field (3.4 ind.), fallow field (3.1 ind.), paddy field (1.8 ind.), swamp (1.4 ind.), and stream (0.2 ind.). There was no significant relationship observed between larval density and DO, pH, salinity, or distance from blood meal hosts (cowshed, pigsty, chicken-house). In the results of average nearest neighbor analysis (ANNA), the distribution of whole points for mosquito larval collection was clustered, and points with over 4.0 larvae per dipper were randomly distributed. Within the study area Haseong-myeon, those points where over 3.0 larvae were collected were of a dispersed distribution.

• Korean journal of applied entomology
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• v.42 no.2
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• pp.125-132
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• 2003

Seasonal fluctuations in density of mosquito species were investigated at two cow sheds near to a large, reedy marsh with fairly polluted brackish water near the coast of Yongam-ri, Cheongryang-myon, Ulsan, Korea. Female mosquitoes were collected biweekly using Nozawa light traps from March to September, from 1999 to 2001. On average, 4,416.1, 5,505.9 and 6,863.8 females per trap night were collected from 10 species in 5 genera in 1999, 2000 and 2001, respectively. Among them, An. sinensis was most abundant (53.4% in species ratio), followed by Cx. tritaeniorhynchus (43.0%), Cx. inatomii (1.6%), Ochlerotatus dorsalis (1.3%) and Cx. pipiens pallens (0.5%). A malaria vector, An. sinensis and a Japanese encephalitis vector, Cx. tritaeniorhynchus were collected 3,663.3 females and 3,142.5 females per trap night from June to September for the years, respectively. According to the biweekly population changes at the area, Cx. inatomii which was dominant species in 1997, was the most abundant in the early July during 1999-2001.

• Journal of Embryo Transfer
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• v.1 no.1
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• pp.59-68
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• 1986

산양의 발정주기의 생리와 조절에 관한 최근 연구 보고들과 한국 재래산양의 대한 이들 연구 결과를 모아 고찰하였다. 온대지역에서 산양의 번식계절은 분명하나 한국재래산양의 경우는 비번식계절이 비교적 짧거나 계절적 무발정율이 낮은 편이며, 비번식계절에는 기능적 황체가 유지되지 않는다. 한국재래산양의 발정주기와 발정지속기간은 타품종과 비슷하며, 발정지속기간의 반복력은 매우 낮으며, 발정주기중의 progesterone과 estradiol-17$\beta$의 소장을 규명하였다. 한국재래산양의 경우 황체기에 PGF2 1-3mg을 투여하면 항체퇴행을 유기할 수 있으나 주기중의 투여시기에 따라 투여후 발정개시 시간에 차이가 있었다. 그리고 pro-gesterone priming후 PGF$\alpha$를 투여함으로써 효과적인 발정동기화를 이룰 수 있었다. 분만후 1개월경과 유상후 12일경에 발정이 재귀되었으며, 첫 발정 후 80%의 산양에서 5-7일의 단발정주기를 나타냈으며, 대부분의 과배란유기 산양에서도 단발정주기를 나타냈는데 이는 황체의 조기퇴행 때문이었다. 초발정후 3-5일에 GnRH를 연속 주사하면 단발정주기의 발생율이 유의적으로 감소되었다.

• The Korean Journal of Zoology
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• v.34 no.2
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• pp.257-264
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• 1991

Studies on the geographical distribution and the seasonal prevalence of chigger mites, with particular reference to L. paflidum, a vector species of tsutsugamushi disease were carried out during the period of July 1989-October 1990. From total 111 field rodents collected during the study period, 4,498 chiggers were obtained and 12 species of 4 genera were identified. L. paflidum, the vector species was the dorninant species, showing 65.6% of the total chiggers. L. scutellare, known as the important vector species of tsutsugamushi disease in Japan was not found in the study area, except Yesan-gun, Chungcheong-namdo where only one specimen was collected. The distribution of chigger mites was clearly localized by species, showing the different dominant species by locality. The population density of L. paflidum was high at two study areas, moderate at one area and very low at six other areas, compared to the other species. The study on seasonal prevalence of L. paflidum population density resulted that they started appearing in September (9.8%), showed the peak in October (45.4%) and November (30.6%), almost disappeared during the period of December-March (1.3-0%), reappeared in April (12.7%) showing a small peak, and again almost disappeared until September. L. palpafe was appeared only in winter and spring (December-April).

• The Korean Journal of Zoology
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• v.36 no.3
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• pp.408-415
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• 1993

Studies on seasonal prevalence and geographical distribution of chigger mites were carried out during the period of August 1990-December 1991, and the results are summarized as follows. From total 325 field rodents collected during the study period, 15,679 chiggers were obtained and 12 species of 4 genera were identified. Leptotrombidium pallidum, a vector species of tsutsugamushi disease in Korea was the predominant species and distributed throughout the country except southern part of Korea, whereas L. scutellare, known also as a vector species was distributed mainly in southern part of Korea. The distribution of chigger mites was strongly localized by species, showing different predominant species at each locality during the same season. The predominant species were L. pallidum(92.3%) at Dorai-5ri, Wondang-ub, Neotrombicula kwangneungensis (44.7%) at Sanjung-ri, Pochun-gun, N. tamiyai (55.1%) at Changgok-ri, Paju-gun, L. orientale (55.2%) at Jangsin-ri, Iksan-gun, and L. scutellare (47.6%) at Sinyong-dong, Iri-si. Study on seasonal prevalence of L. pallidum chiggers resulted that they started appearing in September, showed the peak in November, almost disappeared during the period of December-March, reappeared in April-May showing a small peak, and again almost disappeared until September. L. scutellare showed the peak in October, sharply decreased thereafter, and disappeared during the period of January-September.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2000.05a
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• pp.117-117
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• 2000

• Journal of Plant Biology
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• v.30 no.2
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• pp.117-133
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• 1987

The diatoms were investigated at three lowland swamps in Haman county form July, 1983 to July, 1984 on monthly interval. Seasonal changes of standing crops, the variation of dominant species and species composition were studied. The maximum of standing crops showed bimodal pattern at Chilnalpol and Yujnnup. Dominant species were Navicula crytocephala, Cocconeis placentula, Achnanthes minutissima, Achnanthes lanceolata, Synedra ulna, Eunotia lunaris. Dominant species changed seasonally. Total 166species of diatom were identified. Three lowland swamps supported a rich diatom flora composed of many species typically associated with benthic diatom.

• 한국해양학회지
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• v.22 no.2
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• pp.80-86
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• 1987

Five species of marine cladocerans, Evadne nordmanni, Evadne tergestina, Podon leuckarti, Podon polyphemoides and Penilia avirostris, were found in Chinhae Bay during the years 1982-1983. Incidence of E. nordmanni(April-May) in spring and of E. tergestina(June-December), E. avirostris(June-November) in summer through autumn was noticed during the present study. But P. polyphem oides appeared throughout the year except February. P. avirostris was the most abundant species(21,491indiv./㎥), followed by P. polyphemoides and E. tergestina. Population of E.normanni and P. leuckarti was extremely poor and recorded to be less than 1,000indiv./㎥. Seasonal change in size composition was noticed in E. tergestina and P. avirostris. Increase of length was recorded in P. polyphemoides when water temperature lower than 15$^{\circ}C$.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.358-359
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• 2001

우리나라 남해 서부 해역에 위치한 진도군 해역은 동부는 남해, 남부는 제주해협과 인접한 다도해로서 그 수심은 50m내의로 말은 천해역을 이루고 있다. 이 해역은 황해저층냉수, 황해난류수, 한국 남ㆍ서 연안수, 양자강 희석수 등 계절에 따라 이들 수계의 영향을 받고 있어 이들 수계간에 형성되는 조경역의 변동이 어장 형성에 영향을 미치는 한편, 부어류의 호어장을 형성한다(Gong and Cho, 1972). 또한 년도별 계절별 해황의 변동과 황해저층냉수의 소장에 따라 갈치, 삼치, 병어 등 주요 수산자원의 풍흉에 영향을 미치는 해양 환경적 특성을 지니고 있다. (중략)

• The Korean Journal of Ecology
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• v.22 no.5
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• pp.299-303
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• 1999

Studies were conducted in Mt. Namsan, Seoul, during the summer of 1997 and 1998 using racemic disparlure to determine seasonal occurrence and circadian activity in male gypsy moth, and size of egg mass and wing length of male moth. Male gypsy moths occurred from middle part of July until middle part of August and peaked in late part of July. Circadian activity of male moths initiated from 12: 00h and continued until 21: 00h, and the peak time was between 14: 00h and 17: 00h. Mean number of moths captured per trap in 1997 was larger than that in 1998, however, eggs per mass, egg size and wing length were not significantly different between the two years, 1997 and 1998.