| China has 18,000-kilometer coastline and abundant marine resources. With the industrialization of littoral cities, marine entironment has been severely destroyed. Red tide occurs more and more frequently in China's coastal sea area, and has been one of China's ocean calamities and one of the three severe pollution problems.Red tide is ecological abnormal phenomenon caused by phytoplankton, which reproduce in excess and assemble, resulting in ocean color changed. Red tide occurs randomly, with short duration and large incidence. Airborne hyperspectral remote sensing technique can play an important role in red tide's monitoring. And the precondition is to acquire in situ spectral data of red tide, to grasp red tide's spectral characteristics by data processing and analysis and to set up spectral library of different dominant species of red tide. The thesis is developed in this background.This thesis comprises 5 chapters.In the first chapter, the development and status in quo of ocean spectral data acquisition, processing and analysis are summarized, in order to establish a foundation for corresponding work in this thesis. Three parts of the chapter are: (i) acquisition method of ocean spectral data; (ii) processing method of ocean spectral data; (iii) analysis method of ocean spectral data.Red tide is cultivated by mesocosm experiment with seawater enclosed and captured near the Bayuquan port in the Liaodong Bay. In situ spectral data of red tide are acquired by above water method, according to the condition of mesocosm experiment. Chapter 2 deals with the experiment equipments selection, spectral data acquirement regulations and proceedings that should be noticed in experiment.Chapter 3 is the core of this thesis. After spectral data processing, remote sensing reflectance data of red tide are got, whose dominant species are Leptocylindrus danicus, Chattonella marina, Skeletonema costatum and Mesodinium rubrum respectively. Section 3.1 gives the data processing steps, results and biological details of the dominant species described above.Method of extract spectrum absorption parameters such as absorption depth, width, symmetry and area is given in section 3.2. In the research of correlation between chlorophyll a concentration and absorption parameters of Skeletonema costatum spectra, we find that there is a pretty good positive correlation between absorption depth and chlorophyll a concentration in the spectral range between 450nm and 520nm. Yet in the spectral range between 625nm and 700nm, we find a positive correlation between absorption symmetry and chlorophyll a concentration and a negative correlation between absorption width and chlorophyll a concentration. As the chlorophyll a concentration data that can be used in the correlation analysis are limited quantitatively, these conclusions are preliminary and subjected to be tested.Spectral derivative is a simple and effective method to acquire the wavelengths of extremum points. The wavelengths of reflectance peaks and vales are got by spectral derivative method in section 3.3. Mechanism of them is analyzed. Red tide and normal seawater, as well as some different dominant species of red tide, such as Chattonella marina and Mesodinium rubrum, can be discriminated by using the wavelength information of second reflectance peak.Spectral matching algorithm is applied, such as Spectral Angle Mapping (SAM) in section 3.4 and Cross Correlogram Spectral Matching (CCSM) in section 3.5 in order to discriminate different dominant species of red tide. The results of SAM spectral matching are satisfying: identifications of Mesodinium rubrum and Leptocylindrus danicus succeed, identification of Chattonella marina has wrong possibility and that of Skeletonema costatum fails. The probable reasons for wrong identification and approach to get better results are also pointed out in section 3.4.The results of CCSM spectral matching are even better than those of SAM. Identifications of Mesodinium rubrum, Leptocylindrus danicus and Chattonella marina su...
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