闽南-台湾浅滩近岸上升流区浮游植物碳同化速率的研究

本文采用~(14)C同位素示踪法,测定了浮游植物光合作用速率,结合浮游植物细胞含碳量,计算了不同季节、不同深度下浮游植物碳同化速率常数,讨论了不同环境条件对浮游植物碳同化速率常数的影响。结果表明,闽南-台湾浅滩近岸上升流的形成,是该海域高生产力的主要原因,上升流期间浮游植物复制时间要比非上升流期间浮游植物复制时间缩短1.8倍。同时还表明,温度,光照强度、营养盐是控制浮游植物生长的主要因子。上升流期间营养盐始终保持在较高的水平。是上升流区具有较大的浮游植物碳同化速率常数(3.3d~(-1))的原因之一。适宜该海域浮游植物生长的光照强度在3 000—15 000lx之间,温度的影响可用Goldman和Carpenter模式近似表示。

STUDY ON THE CARBON ASSIMILATION RATE OF PHYTO-PLANKTON IN THE UPWELLING REGION IN MINNAN-TAIWAN BANK FISHING GROUND

Photosynthetic rates of phytoplankton were determined in situ with 14C-Iracer method. The constants of carbon assimilation rate of phytoplankton were calculated for samples collected from different depths in various seasons, combined with the data of carbon contents in algal cells. The effects of environmental conditions on the constant of carbon assimilation rate of phytoplankton were discussed. The results indicated that the formation of the coastal up welling in Minnan-Taiwan bank fishing ground was the major factor for the high productivity in this sea area. Doubling time of phytoplankton during the upwel-ling period was 1.8 times less than that during the non-upwelling period. In addition, temperature, light intensity and nutrients were also the important factors contorolling the growth of the phytoplankton. The maintenance of higher nutrients was one of the reasons for larger constant of carbon assimilation rate of phytoplankton(3.3d-1). The optimum light intensity for the growth of phytoplankton in this sea area ranged from 3000 to 15000lx. The effect of temperature can be approximately described with the model of Goldman and Carpenter.