强壮前沟藻Amphidinium carterae Hulburt生消过程中水体总吸收特性研究

Total absorption characteristics of alga Amphidinium carerae Hulburt in growth and decay periods

基于2011年7月藻类培养实验期间的实测数据研究了强壮前沟藻Amphidinium carterae Hulburt生消过程中水体的总吸收特性。结果表明,强壮前沟藻本次培养周期共21天,前15天为生长期,之后进入消亡期;整个生消过程中水体吸收光谱变化明显,未见440nm波段浮游藻类蓝光吸收峰,但675nm波段红光吸收峰突出,消亡期总吸收系数的日变化明显大于生长期,总吸收系数与叶绿素浓度的时间序列变化趋势一致;总吸收系数的波段关系良好,但不同生长时期相同波段的拟合曲线存在显著差别,消亡期的拟合曲线普遍高于生长期,且整体看来随波长增加,两曲线逐渐接近,到667、678nm波段时几乎重合;特征波段(440、675nm)的总吸收系数与叶绿素浓度存在较好的乘幂函数关系,拟合曲线与藻种的生长阶段有关,决定系数均在0.98以上。

Based on the data measured during an algal culture experiment in July 2011, this paper analyzed absorption characteristics of alga Amphidinium carerae Hulburt in growth and decay periods. The results showed that in 21 days of the algal culture the growth period started from the 1st to the 15th day, and then the alga entered into the decay period. Meanwhile, the total absorption spectra varied notably： the absorption peak of phytoplankton was not found in the blue band （440nm）, but was obvious in the red band （675nm）. Diurnal variation of absorption coefficient in the decay period was more significant than that in the growth period. Besides, the total absorption coefficient and the chlorophyll concentration displayed a consistent tendency. Moreover, the inter-band relationship of the total absorption coefficient at 675 nm with other bands was quite remarkable; but in different periods, the fitted curves showed significant differences for the same band; and the curves in the decay period were above those in the growth period. Overall, both curves became closer and closer with increasing wavelength, and were almost overlapped at 667 and 678nm. For some specific bands （440 and 675nm）, high correlations of power function between total absorption coefficient and chlorophyll concentration were found （the coefficients of determination surpassed 0.98）, and the fitted curves were related to algal growth stage.