中文摘要：

在不同光照和营养盐结构条件下半连续培养球形棕囊藻和3种硅藻,研究光照、营养盐限制和硅藻竞争对球形棕囊藻囊体形成的影响。结果表明：高光照显著促进了藻类的生长,球形棕囊藻在低光环境下几乎不形成囊体。球形棕囊藻和3种硅藻对光限制和P限制更加敏感,而在N限制环境中均具有相对较高的生物量。粒径较小的球形棕囊藻游离单细胞和中肋骨条藻在营养盐和光限制条件下比粒径较大的细胞具有更强的竞争能力。硝酸盐是球形棕囊藻囊体形成的营养基础,但是营养盐结构并未改变棕囊藻囊体形态。具有两种生活史状态有利于球形棕囊藻度过资源限制的环境,从而有利于球形棕囊藻在硅藻藻华之后再次形成藻华。

英文摘要：

Abstract： Phaeocystis globosa and three diatom species were grown in semi-continuous culture in order to investigate the effects of irradiance, N：P supply ratio and the competition from coexisting diatoms on the colony formation of P globosa. Experiments were conducted with two light regimes under N- and P-limited conditions. The results showed that high light increased the growth of all species of phytoplankton, and that higher phytoplankton biomass was observed in the N-limitation culture. Due to their smaller cell volume, Skeletonema costatum and P globosa solitary cells possessed higher competition relative to Thalassiosira weissflogii and Chaetoceros curvisetus. P globosa failed to form colonies under low light conditions. Nitrate was the favored nitrogen source for the development of colonies, however the architecture of colonies was not affected by different N：P supply ratio. The life cycle transformations permitted P globosa to survive when light and nutrient became limited, partly explaining the mechanisms that P globosa blooms occurred after diatom blooms along the coasts.