| 摘要: |
| 采用荧光测量方法研究成功的海水叶绿素a现场测量仪，是用于海上现场实时测量海洋中浮游植物体内叶绿素a含量的新型海洋仪器。本仪器采用低功耗、高强度、低重复频率、窄脉冲宽度的脉冲氙灯，为激发光源及相应的脉冲检测技术测量荧光信号。该仪器可在海表层至50m水深内任一日光强度下工作；测量海洋中浮游植物体内叶绿素a的浓度范围为1×10-6-1×10-9 g/cm3；当仪器走航拖曳速度为2 m/s时，其空间分辨度为1m，仪器具有海上现场测量实用价值。 |
| 关键词: 叶绿素a 现场测量仪 荧光测量方法 脉冲检测技术 |
| DOI： |
| 分类号: |
| 基金项目:“七五”国家重点科技攻关项目，75－76－04－06号 |
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| STUDY ON IN-SITU MEASURING SET FOR CHLOROPHYLL-a IN THE SEAWATER |
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Xia Daying1, Wang Zhenxian1, Xa Jingfang2, Xia Ronghuan1, Xin Haiying1
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1.First Institute of Oceanography, SOA, Qingdao 266003;2.Department of physics, Fudan university, Shanghai 200433
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| Abstract: |
| This article describes an in-situ instrument of the chlorophyll-a in seawater which has been successfully developed on the basis of fluorometry. It is mainly used for measuring the chlorophyll-a concentration in phytoplankton in the sea site so that the distribution of sea organisms resources can be assessed. The instrument use the pulsed xenon lamp as the excited light resources which has the characteristics of low power consumption, high intensity, low repetition rate and narrow pulse width and also use the relevant pulsed detecting technology (i. e. the Boxcar integrating circuit) for detecting the fluorescent signal. The signal strength is ratioed against the lamp intensity for each flash, by using the detecting methods of double light route and double channel at the same time, so that the accuracy of every measuring figure can be ensured, and signal variation due to undulation of the pulsed xenon lamp output intensity can be effectively eliminated. In order to effectively separate the fluorescence produced by the chlorophyll-a of the phytoplankton in the sea which is shone by the excited light and the scatter light from the excited light, we use high block coefficient narrow band filters, the center wavelength of the excitation filter is 440nm, and the fluorescent eminence filter's center wavelength is 685 nm. In this way, the fluorometric signal strength which is received by the receivers can be ensured to reflect the fluorescence of chlorophyll-a in the phytoplankton, and furthermore the interference from the inherent fluorescence in the seawater can be effectively prevented.
The instrument can work from the sea surface to a maximum depth of 50 m, at any sunlight intensity, for detecting concentration range of chlorophyll-a in the phytoplankton in the ocean from l×10-6-l ×10-9 g/cm3; when the instrument is towed at a speed of 2 m/s, its space resolution is lm, and this is of practical value to us. |
| Key words: Chlorophyll-a, In-situ measuring set, Fluorometry methods, Pulsed detecting technique |
