活体浮游植物的叶绿素荧光发射特性与激发光源的波长和强度密切相关，实验选取普通小球藻和铜绿微囊藻作为测试对象，获取了中心波长为450、525、590、620 nm 4个波段LED激发下的叶绿素荧光诱导特性。研究表明，当对应波段上的激发光强分别低于2.8、4.6、3.8、4.3 μmol/(m2·s)时，荧光诱导曲线始终保持在稳定水平本底荧光(Fo)；分别记录同一信号增益下上述4个波段激发时的Fo和激发光光合有效辐射(PAR)，通过拟合可以得到一个粗略的四点离散激发光谱，并结合对应波长处的吸收率数据分析了波长对荧光发射的影响；对经浓度为0.4 μmol/L的二氯苯基二甲脲(DCMU)处理并由90%的乙醇提取叶绿素后的样品和活体浮游植物样本进行对比分析，获得了有显著差异的荧光诱导曲线。实验结果为浮游植物光合作用活性原位测量提供了理论基础和数据支持。

Chlorophyll fluorescence emission characteristics of phytoplankton in vivo is closely related to the exciting wavelength and intensity. The fluorescence induct curves under 4 wavelengths of LED (450, 525, 590, 620 nm) and various intensities using chlorella vulgaris and microcystis aeruginosa are tested. Research results show that smooth induct curve are obtained when corresponded exciting light intensity are below 2.8, 4.6, 3.8 4.3 μmol/(m-2·s). Fluorescence intensities of Fo are recorded at the same gain setting, which represent the pigment level. A discrete spectrum can be obtained when considering exciting light photosynthesis active radiation (PAR). Fluorescence affected by wavelength is analyzed combining absorbance data. Significant different chlorophyll fluorescence induct curves are got between phytoplankton in vivo, extracted by 90% ethanol and addition with 0.4 μmol/L 3-(3,4-dichlorophenyl)-1, 1-dimethylurea (DCMU). This work can provide theoretical and data support for phytoplankton photosynthesis activity measurement.