• Journal of Wetlands Research
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• v.20 no.2
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• pp.124-130
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• 2018

This study was conducted to identify the characteristics of bird population dynamics using unmanned monitoring system in rice paddy. We compared the similarity of population dynamics of birds between unmanned monitoring system and field survey, and evaluated the spatial and temporal patterns of population dynamics of birds using the unmanned monitoring system. The monitoring using the system was conducted from January 1, 2014 to December 31, 2016 in Cheolwon, Dangjin, Buan, and Heanam. The images from the system were obtained at 10-min intervals from 6:00 to 20:00. The field survey was conducted once a month in Dangjin from January to December 2016. Total 91,980 images were obtained from the unmanned monitoring system. We extracted the number of individuals for herons, shorebirds, and waterfowl from the images. The population dynamics of waterbirds using the unmanned monitoring system were similar to that in field survey. Especially, population dynamics of herons was more similar than other waterbirds. It was identified that the population dynamics of herons using the unmanned monitoring system was different among the Cheolwon, Dangjin, Buan, and Heanam. Furthermore, the unmanned monitoring system was available on various time scale such as month, day, and minute. It is expected that long-term data storage using the unmanned monitoring system can be used to identify in detail and forecast the population dynamics of birds in rice paddy.

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.35-42
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• 2004

To examine the species composition and population fluctuation of butterflies at Mt. Yudal, Mokpo, we collected butterflies from May, 2001 to April, 2002 by dividing the study site into four subyegions. As a result, seven families comprising 40 species were identified. The patterns of population fluctuations at the four subregions showed that the lower the elevation the higher the number of species and individuals. Monthly fluctuations of buttefly species produced an M-shaped curve, whereas those of individuals produced a monotonic curve with a maximum peak during August. To see effectively the changes of numbers of species and individuals, we calculated the indices of species richness and evenness by subregions and months. As a result, both indices fulfilled the primary criterion of independence and showed more or less negative association: when heterogeneity is higher, evenness is lower. Examination of butterfly populations over long-term periods might provide an evidence of global warming and a guideline to conserve and manage habitats.

• Journal of Wetlands Research
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• v.20 no.3
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• pp.256-262
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• 2018

Multiple temporal scale can be a useful method to understand population dynamics in ecosystem. The multi-temporal scale approach for population dynamics has rarely been researched till lately. This study was carried out to identify the factors in affecting the population dynamics of herons, including Eastern Cattle Egret (Bubulcus coromadus), Grey Heron (Ardea cinerea), Great Egret (A. alba), Intermediate Egret (Egretta intermedia) and Little Egret (E. garzetta), at rice paddy fields of Seokmun-myeon in the city of Dangjin, South Chungcheong Province during the main breeding periods from 2014 to 2017. We identified the population dynamics of herons at different time interval (day and month) using the unmanned monitoring system. As a result, monthly population dynamics was mostly affected by time, mean temperature and mean precipitation, whereas daily population dynamics was affected by mean temperature and habitat types. The results suggest that there are differences in the factors affecting the population dynamics of herons according to the time scale.

• Korean Journal of Ecology and Environment
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• v.38 no.2 s.112
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• pp.146-159
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• 2005

Fifty-four zooplankton species from Daecheong Lake were identified during the research period from June to October 2001. The representative zooplanktons mostly comprised the index species indicating the intermediate stage from oligosaprobity to ${\beta}$-mesosaprobity. During the blooming season of blue-green algae, the population of large cladocerans like Daphnia galeata precipitously decreased in size, while rotifers and small cladocerans like Bosmina longirostris increased in population size. Therefore, soon after the peak of the blooming of blue-green algae, whole zooplankton standing crop and number of species showed the tendency of recovery, or even the sharp increase. The population size of Daphnia galeata was affected very sensitively by the change of cyanobacterial density.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.200-201
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• 2000

와편모조류의 대부분은 생존에 불리한 환경조건이 되면 저질에 침적되어 휴면포자의 형태로 휴면시기를 보내다가 온도, 광, 산소, 영양염 등의 환경요인 변동과 내재적 주기에 의해 발아가 유도된다. 이러한 휴면포자는 "개체군 씨앗 "으로서 지역적 적조발생의 잠재력이 되는 것으로 시사되어 왔다. (중략)어 왔다. (중략)

• The Korean Journal of Ecology
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• v.28 no.1
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• pp.45-53
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• 2005

Urban stream is an important place supporting urban ecosystem. This study was carried out to clarify the role of Jungrangchun for wintering waterbirds in Seoul. We monitored the fluctuation of waterbirds population using our census data (1997/98 winter) and pervious census data (the Ministry of Environment and National Institute of Environmental Research $1999{\sim}2004$). Wintering behaviours of common teals (Anas crecca) were also observed to understand the habitat use of waterbirds in this area. As a result of this, Jungrangchun was an important place to support $3,004\sim8,237$ wintering birds, mainly dabbling ducks and diving ducks. The population of diving ducks showed high annual fluctuation whilst the population of dabbling ducks regularly used this area every year The maximum number of waterbirds foraged and rested in late January and late February. In daily use, the number of waterbirds increased on afternoon and rapidly increased after sunset. It is assumed that waterbirds used this area not only as a nocturnal feeding site but also daytime feeding site. Thus, this result suggest that Jungrangchun is important for not only the daily use but also the nocturnal use of wintering waterbirds. The number of diving ducks was increased with low temperature and high wind speed. Therefore, this area was also a shelter of diving ducks on chilly and windy day.

• Korean journal of applied entomology
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• v.38 no.3
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• pp.231-240
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• 1999

The long-term tend an pattern changes of Chilo suppressalis(Walker) occurrence in Suwon were analyzed and the forecasting models for spring emergence of C. suppressalis in Suwon were developed. From 1965 to 196, the population dynamics of C. suppressalis in Suwon shows a cyclic fluctuation with one large peak an one small peak, and its periodicity was ca. 36 generations(18 years). C. suppressalis population dynamics in Suwon was characterized as controlled by the endogenous dynamics dictated by the 1st order negative feedback mechanism (fast density dependence). The dynaics mechanism of C. suppressalis populations was not changed although its population density decreased drastically over the years. Using th dta of C. suppressalis spring occurrence in Suwon, forecasting models for spring emergence of C.supressalis were developed based on temperature-dependent development model or degree days. In general, these models well described the C. suppressalis spring emergence pattern in Suwon. Also, forecasting problems in spring moth emergence related with C. suppressalis population dynamics were discussed.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.400-401
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• 2000

국내에서 적조연구는 국립수산진흥원에서 남해를 비롯 우리나라 연안의 모니터링과 한양대학교 연구팀의 마산만에 관한 연구가 초기부터 활발하게 이루어졌다. 적조 연구는 주로 적조원인 플랑크톤의 발생규모, 계절적 변동과 그 때 수질환경을 조사하였고 대체로 군집 수준에서 다루어졌다 (박과 김, 1967; 유와 이, 1976; Yoo and Lee, 1979; 박, 1982). 우리나라의 적조 연구는 주로 마산-진해만애서 이루어져 왔다. 마산만과 진해만을 비롯 행암만, 덕동만, 진동만, 칠천수로 등이 그 대상지가 되었으며 이 지역에서는 그동안 상당한 자료가 축적되어 왔다. 하지만 본 연구 대상지역인 광양만에서 적조연구에 관한 자료가 미흡하여 본 연구는 기존의 적조생물의 군집 수준의 연구와 유사하다. 개체군의 변동을 파악하는데 중점을 두었고 광양제철소를 중심으로 하여 남해 일대에 걸쳐 모니터링을 하고 수환경의 특성과 개체군 변동을 동시에 조사함으로서 제철소 건립 후 광양만에서 적조 발생의 최근적조 양상을 분석하였다. (중략)

• Proceedings of the Korean Society of Soil Zoology Conference
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• 1985.01a
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• pp.6-6
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• 1985

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.199.2-199
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• 1995