• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.309-314
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• 2013

The concentration of terpene (18 species) was measured from spring to fall in ambient air and essential oil at three different forests located in Jeollanamdo province. Sampling was conducted at 4-hour-interval a day of each season. In the ambient air, ${\alpha}$-pinene, ${\beta}$-pinene and 2-carene were the most abundant compounds throughout the sampling periods and areas. The highest three-season average concentration of total terpene was 2,597 pptv at Jeamsan(Mt.) in Boseong which was predominantly populated by Pinaceae. The seasonal averages were observed to peak during spring with their max at Palyeongsan(Mt.) in Goheung and Jeamsan(Mt.) in Boseong, and during fall at Woodland in Jangheung. Most of terpenes had diurnal variations with higher concentrations during the daytime, and lower during the nighttime. However in essential oil, the highest annual average concentration of total terpene was $798{\mu}g/dry-g$ at Goheung which was predominantly populated by Chamaecyparis obtusa. Also, the component proportion ratio showed different distribution between ambient air and essential oil. From the results of this study, we suggest that Chamaecyparis obtusa species is more useful, and younger tree is more economical than older one, and spring is the best season for lumbering in order to use essential oil.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.400-406
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• 2018

In this experiment the effect of supplemental lighting on the growth and yield of cucumber (Cucumis sativus L. 'Fresh') plants during low radiation period of winter season were investigated in glasshouses using common high-pressure sodium (HPS) lamps and newly developed plasma lighting system (PLS) lamps. Plants grown without supplemental lighting were considered as a control. Supplemental lighting was provided from November 20th, 2015 to March 15th, 2016 to ensure 14-hour photoperiod (natural+supplemental light), also lamps were operated automatically when the outside sun radiation levels were less than $100W{\cdot}m^{-2}$. Spectral analysis showed that HPS lamp had a discrete spectrum, lacked of the radiation in the 400-550 nm wave band (blue-green light), but had a high output in the orange-red region (550-650 nm). A higher red light output resulted in an increased red to far-red (R/FR) ratio in HPS lamp. PLS had a continuous spectrum and had a peak radiation in green region (490-550 nm). HPS has 12.6% lower output in photosynthetically active radiation (PAR) but 12.6% higher output in near infra-red (NIR) spectral regions compared to PLS. Both HPS and PLS lamps emitted very low levels of ultra-violet radiation (300-400 nm). Supplemental lighting both from HPS and PLS lamps increased plant height, leaf number, internode number and dry weight of cucumber plants compared to control. Photosynthetic activity of cucumber plants grown under two supplemental lighting systems was comparable. Number of fruits per cucumber plant (fruit weight per plant) in control, PLS, and HPS plots were 21.2 (2.9 kg), 38.7 (5.5 kg), and 40.4 (5.6 kg), respectively, thereby increasing yield by 1.8-1.9 times in comparison with control. An analysis of the economic feasibility of supplemental lighting in cucumber cultivation showed that considering lamp installation and electricity costs the income from supplemental lighting increased by 37% and 62% for PLS and HPS lamps, respectively.