厦门西港浮游植物吸收磷酸盐的粒级特征
Size-Fractionated phosphate uptake by phytoplankton in West Xiamen Harbour
Abstract
厦门西港微型浮游植物(3~20μM)吸收磷酸盐的百分比、吸收速率常数和单位体积吸收速率均最大,分别为74.85%、8.28x10-5/S和5.38x10-5μMOl/(dM3·S),小型浮游植物(20~200μM)次之,超微型浮游植物(0.2~3μM)最小;单位叶绿素A的吸收速率是超微型浮游植物最大[5.38x10-5μMOl/(μg·S)],微型次之,小型最小。相关分析表明各粒级浮游植物吸收磷酸盐的百分比与相应粒级浮游植物的叶绿素A含量和光合速率的百分比呈良好的正相关关系。 By using carrier-Free 32P radiotracer method, the study on size-Fractionated phosphate uptake rate,rate constant and upake percentage by phytoplankton was carried out in West Xiamen Harbour.The correlationship among phosphate uptake, standing crop (Chl-a) and photosynthetic rate is discussed.The results indicated that nanophytoplankton (3~20μm)played the most important role in phosphate uptake percentage(74.85 % ),rate constant (8.28 ×10-65/s) and uptake rate[by volume, 5.38×10-5μmol/(dm3·s)] in the three diFFerent size phytoplanktons, but in uptake rate (by biomass), picophytoplankton (0.2~3μm) [5.38×10-5μmol/(μg· s) ] was more important than nanophytoplankton [1.79×10-5 μmol/(μg·s ) ] and microphytoplankton (20~200μm) [1.14 ×10-5μmol/ (μg· s )].The good positive correlationship was Found between phosphate uptake percentage with standing crop(Chl-a) and photosynthetic rate, respectively.This study Further showed that nanophytoplankton played a key role in phosphorus biogeochemical cycle in West Xiamen Harbour.