碩士 / 雲林科技大學 / 環境與安全工程系碩士班 / 97 / The vegetation emitted biogenic volatile organic compounds (BVOCs) readily reacts with hydroxyl radicals (OH-) and nitrogen oxides (NOx) to produce of ozone (O3) and secondary organic aerosol. However, the quantification of VOC exchange on the ecosystem scale is still an analytical challenge. In the present study we tested and applied two technologies of micrometeorological approaches, multi-relaxed eddy accumulation and eddy covariance to measure the flux of BVOCs on a flux tower at mid-elevation (1200 m) near Chia-Yee country in middle Taiwan from November 2007 to April 2009. The range of effective fetch at the sampling site is estimated using the available equations to evaluate the influence area of this study. The measurement of BVOC flux under different seasons, day and night, hour and mixed layer are analyzed.
The results of the empirical coefficient (b) in REA method evaluated by vertical wind data and temperature were 0.52±0.09 and 0.58±0.08, respectively. The atmospheric stability classification between A and B showed that the eddy was still vigorous at experimental site. Obviously, empirical coefficient estimated by vertical wind data was close to the literature ones, and the results can also prove that MPREA is a trustworthy technique. The major species detected in Spring, Summer, Autumn and Winter are hexanal, p-cymene, hexanal and hexanal respectively. The species of day and night are different and the major species were hexanal, p-cymene, limonene, respectively. The BVOCs flux measured at day time is double in day time that of night time due to higher temperature and PAR.The ratio of individual species to total flux of Hexanal, p-cymene, limonene, and MVK were 38%, 21%, 10%, 10%, respectively.
The relationships of isoprene and monoterpene flux of C. Sinensis and temperature are developed using Guenther method in 1993 (G93). The range of monoterpene empirical coefficient (bM) of total monoterpene、α-pinene、β-pinene and limonene were 0.12, 0.09, 0.16 and 0.13. The flux estimation using estimated b value estimated in (G93) are 11, 76, 61 and 68μg m-2 h-1 respectively.
| Identifer | oai:union.ndltd.org:TW/097YUNT5633021 |
| Date | January 2009 |
| Creators | Ming-Feng Chang, 張銘峰 |
| Contributors | Chu-Chin Hsieh, 謝祝欽 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 111 |
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