三亚鹿回头海域珊瑚、石莼和碎石反射率光谱分析

以南海三亚湾鹿回头海域八种常见造礁石珊瑚优势种的反射率光谱为代表，用光谱仪测量它们和此海域常见底质石莼以及碎石的反射率光谱。通过反射率、导数光谱法研究了三亚鹿回头海域造礁石珊瑚、石莼和碎石的光谱差异。石莼于561.4 nm处出现反射率高达48%左右的显著波峰，在500～700 nm波长范围和造礁石珊瑚反射率差异较大；碎石反射率明显高于造礁石珊瑚反射率，整体差异显著。导数分析结果表明造礁石珊瑚、石莼和碎石可区分波段为：造礁石珊瑚与石莼主要为一阶导数在485～487，505～510，515～529，559～578，587～593，598～603和667～670 nm等波段。二阶导数在494.4～505.7，524～534.5，543.6～561.4和567.2～579.7 nm波段。四阶导数在515.8～430，621～627.1，628.8～635.6，639.3～645，661.8～669.8和678.4～682.4 nm等波段。造礁石珊瑚与碎石一阶导数反射光谱，主要为400～413.7，414～418，484.8～486.9，506～509.6，514.5～528.9，576.9～587.6和602.7～653.4 nm波段。二阶导数主要为，451.6～461.6，564.5～570.7和677～685 nm。四阶导数主要为，412.6～425.3，459.8～467，467.7～470.6，535.6～540.8，583.8～591.4，654.4～659.8和670.8～680 nm等波段。

Reflectance Analysis of Scleractinian Coral,Ulva and Coral Rubble in Luhuitou Sanya Bay

Reflectance spectra of eight common scleractinian coral species were chosen to represent the reflectance of corals in the sea area of Luhuitou Sanya Bay in the north-western South China Sea (SCS). Reflectance spectra of these scleractinian corals, ulva and coral rubble were measured using a fiber spectrometer. Then spectral reflectance analysis and derivative spectroscopy were used to study the difference in the reflectance spectrum between reef building scleractinian coral, ulva and coral rubble in this sea area. The results showed that reflectance peak of ulva appeared at 561.4 nm, and its value was as high as 48%; reflectance difference of ulva and scleractinian coral was very significant in 500~700 nm; reflectance of coral rubble was significantly higher than that of coral reflectance spectrum with significant differences. Derivative analysis results showed that the distinguishable bands of scleractinian coral, ulva and coral rubble were as follows: scleractinian coral and ulva, first order derivatives are mainly in 485～487, 505～510, 515～529, 559～578, 587～593, 598～603 and 667～670 nm bands. The second order derivatives are mainly in 494.4～505.7, 524～534.5, 543.6～561.4 and 567.2～579.7 nm bands. The fourth order derivatives are mainly in 515.8～430, 621～627.1, 628.8～635.6, 639.3～645, 661.8～669.8, and 678.4～682.4 nm. First order derivatives of scleractinian coral and coral rubble are mainly in 400～413.7，414～418，484.8～486.9，506～509.6，514.5～528.9，576.9～587.6 and 602.7～653.4 nm bands. The second order derivatives are mainly in 451.6～461.6, 564.5～570.7 and 677～685 nm. The fourth order derivatives are mainly in 412.6～425.3，459.8～467，467.7～470.6，535.6～540.8，583.8～591.4，654.4～659.8 and 670.8～680 nm bands.