To investigate the relation of sun-induced fluorescence peak near700nm with chlorophyll a concentration

data set of the reflectance spectra of red tide species such as Gymnodinium sp.

Heterosigma akashiwo

Ceratium furca and other algae for instance Nitzschia closterium

Dicrateria zhanjiangensis Hu.

Blue algae sp.

Chlorococcum sp.

Platymonas helgolandica var tsingtaoensis

chlorella sp.getting from in situ and culture was used.R maxred normalized to R 560 was correlated highly with chlorophyll a concentration with R>0.82.Along with algae’s difference

the coefficient a of the relationship of R maxred /R 560 with chlorophyll a presented big change.The regressions equation in the form of R maxred /R 560 =a（chl a） b revealed that coefficient a varied from0.037to1.135and b varied from0.094to0.727.Si-multaneously this work established the relationship of the peak position of algal fluorescence with chlorophyll a concentra-tion.All of the Regression coefficients were bigger than0.75except Chlorococcum sp.with0.57.The position of phyto-plankton’s fluorescence peak was shifted to the red light of spectrum.Varied with the species of algae

the shift of peak position was not the same.The Heterosigma akashiwo was the biggest

and the shift of peak position of other algae per10mgm -3 was between0.1and0.3nm.No shift was detected of Dicrateria zhanjiangensis Hu.and Chlorococcum sp.in the scope of experimenting chlorophyll a concentration.