• Journal of Korean Society of Forest Science
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• v.112 no.1
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• pp.117-125
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• 2023

Outbreaks of Ramulus mikado (Insecta: Phasmatodea: Phasmatidae) in the hilly areas of Mt. Bongsan, Mt. Cheonggye, and elsewhere in Seoul and Gyeonggi occurred from 2020 to 2021, causing serious defoliation. We evaluated the insecticidal effects of six eco-friendly organic materials and the insect-pathogenic fungus Metarhizium anisopliae against R. mikado. The fungus was isolated from naturally dead bodies of R. mikado in forest ecosystems. The results revealed that three eco-friendly organic materials containing azadirachtin or geraniol as active ingredients showed high mortality in the range of 85.2%-100%, which were rates similar to that of the chemical insecticide fenitrothion emulsifiable concentrate. All R. mikado adults that were sprayed with a conidial suspension of M. anisopliae at different concentrations were killed within a few days. In conclusion, three eco-friendly organic materials and M. anisopliae could be good alternatives to chemical insecticides.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.2
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• pp.133-151
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• 2019

This study aims to analyze cold air characteristics in the watershed areas and to suggest strategies for utilizing them in urban ventilation corridor plans. For this purpose, the Jungnangcheon watershed and Uijeongbu-si in the northern part of Gyeonggi province, and Anyangcheon watershed as well as Yangjaecheon Tancheon watershed and Gwacheon-si in the southern part were selected as study areas. We used KALM (Kaltluftabflussmodell), a cold air simulation model developed in Germany and identified both the cold air flow and the height of cold air layer generated during 6 hours at night. Uijeongbu City is located on the main stream of the Jungnangcheon watershed, and the local cold air from the southern outskirts is an important part of Uijeongbu-si's overall ventilation corridor planning. In addition, the cold air generated in the vicinity of Mt. Sapae flows into the central business district near the city hall and plays a major role in regulating the thermal environment of the city. But, the cold air flows in the eastern part of Uijeongbu-si was not smoothly. The cold air flow generated in the east of Gwanak Mountain and in the west of Cheonggye Mountain was the most active in the northern part of Gwacheon-si. This flow is also a major ventilation corridor in Anyangcheon watershed as well as Yangjaecheon Tancheon watershed. But, the southern part where the cold air flow is not smooth is planed to be developed as 'Gwacheon Knowledge Information Town Public Housing District', so rapid development is expected in the future. Hence, it is suggested that an additional ventilation corridor plan should be established based on the detailed local wind flow analysis.