摘要: |
依据激光感生荧光的原理和叶绿素分子的荧光谱特性,研制一套激发波长为532nm的海洋激光雷达系统,用于海洋表层叶绿素分子浓度的快速测量。应用该系统于1994年10–11月进行一次长距离的海上现场实验,对东海(27-32°N,122—129°E)21个站位的表层叶绿素浓度进行了测量,得到0.15 μg/L–1.10 μg/L范围的表层叶绿素分子的浓度分布。测量结果与水样的分光光度计测量结果相吻合。 |
关键词: 海洋激光雷达 激光荧光 喇曼散射 叶绿素浓度 |
DOI: |
分类号: |
基金项目:国家自然科学基金资助项目,49486007号 |
附件 |
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METHOD AND EXPERIMENT FOR MEASURING SEA SURFACE CHLOROPHYLL CONCENTRATION USING LIDAR |
CHEN Wei-biao,WU Dong,ZHANG Ting-lu,LIU Zhi-shen
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Ocean Remote Sensing Laboratory of State Education Commission, Ocean University ofQingdao, Qingdao. 266003
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Abstract: |
By measuring the laser induced chlorophyll molecule fluorescence and water molecule Raman scattering, the sea surface concentration of chlorophyll can be deduced from the fluorescence normalized by the Raman scattering. An ocean lidar system with transmitter of frequency doubled Nd: YAG 532 nm laser was developed to measure the concentration of chlorophyll based on the above principle. An interference filter with center wavelength of 683.7 nm and bandwidth of 20 nm is used to detect the chlorophyll fluorescence. The Raman scattering is measured by a monochrometer with center wavelength of 650 nm and bandwidth of 10 nm. The ocean lidar system was installed on DONGFANGHONG research ship, and was deployed for long track observation in the East China Sea (27°-32° N, 122°-129° E) during October and November, 1994. The experiment is one parts of JGOFS plan of China. The distribution of sea surface chlorophyll concentration of 21 stations was obtained by the ocean lidar. The measured concentration ranged from 0.15-l.10 μg/L. The ocean lidar system's result is close to the spectrophotometer’s result, and the correlation coefficient of the two results is 84%. The error sources of the lidar system are analyzed in the paper, and the big bias is found in the high concentration. This study showed that the ocean lidar system is superior to the concentration measurement method in such features as real-time and easy-operation. It can be used to detect the sea surface chlorophyll concentration in situ and as a simultaneous observation instrument of the ocean color satellite. |
Key words: Ocean lidar, Laser fluorescence, Raman scattering, Concentration of chlorophyll |