长江口冬季叶绿素活性荧光及遥感分析

Research on active fluorometer and remote sensing technology of Changjiang Estuary in winter

通过对比及分析长江口及其邻近海域冬季叶绿素的实测数据、活性荧光数据以及遥感数据,探讨长江口冬季叶绿素的分布情况以及叶绿色荧光活性仪和遥感手段的应用价值。结果表明,冬季调查海域的叶绿素平均值为0.85 mg/m3,长江口南方的沿岸海域存在一处平均浓度约为1.30 mg/m3的叶绿素高值区。利用叶绿素活性荧光仪测量的最大荧光Fm和最小荧光Fo能较准确的体现叶绿素的分布趋势,最大量子产量Fv/Fm则可以体现浮游植物的生长状态,对研究不同环境因素(营养盐、温度、光等)对浮游植物生长的限制情况具有一定的指示作用。另外,利用遥感手段反演所得的叶绿素精度较低,平均浓度约为0.94 mg/m3,虽然略高于实测值,但能较好的体现叶绿素分布的趋势。

In situ winter Chlorophyll a data in Changjiang Estuary and the adjacent sea were compared with the active fluorescence data and remote sensing data,in order to analyze the distribution of chlorophyll a in winter and the potential applications of active fluorometer and remote sensing technology. The result shows that the mean chlorophyll a concentration of the investigate area in winter is approximately 0. 85 mg / m^3 with a high value zone（ 1. 30 mg / m^3） located at southeast of Changjiang Estuary. What＇s more,the value of the maximal fluorescence Fm and minimal fluorescence Fo measured by Phyto Flash submersible active fluorometer can give a very accurate depiction of the real surface distribution of chlorophyll a. Distribution of the maximal quantum yield（ Fv / Fm） can be used to evaluate the responses of phytoplankton to different limiting factors such as nutrient,temperature and light,etc. In addition,though the average of chlorophyll a retrieved by remote sensing data（ 0. 94 mg / m^3） is a little higher than the measured value,it still has the practical value to reflect the real trend of chlorophyll a distribution.