不同藻类水体太阳激发的叶绿素荧光峰(SICF)特性研究

Interpretation of Sun-induced Fluorescence Peak of Chlorophyll a on Reflectance Spectrum of Algal Waters

采用现场实测和室内培养两种方式测定了甲藻、赤潮异弯藻、海洋蓝绿藻、叉角藻赤潮和新月菱形藻、叉鞭金藻、塔胞藻、扁藻和小球藻等非赤潮藻类光谱曲线,采用度量太阳激发的叶绿素荧光峰高度的Rmaxred/R560比值法,建立了不同藻类Rmaxred/R560与叶绿素a浓度的关系,R>0.82。随藻类的不同,Rmaxred/R560与叶绿素a的关系发生较大的变化,其关系方程的系数a的变化范围为0.037—1.135之间,b的变化范围为0.094—0.727之间。同时建立了不同藻类荧光峰位置与叶绿素a浓度的关系,除海洋蓝绿藻为0.57外,R均大于0.75。随叶绿素浓度的增加,浮游植物反射光谱荧光峰的位置向红光方向移动。随藻类不同,移动的幅度有所差异,赤潮异弯藻的移动幅度最大,其它藻类每10mgm-3浓度的移动幅度介于0.1—0.3nm之间。叉鞭金藻和塔胞藻在实验的浓度范围内未见移动。

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.