厦门海域春夏季微型浮游动物对浮游植物的摄食压力初探

应用稀释法对厦门海域浮游植物生长率(k)和微型浮游动物的摄食率(g)进行了估算。结果显示：5月，西海域18测站k、g分别为2．41、0．78d^-1；南部海域27测站分别为2．43、1．32d^-1。8月18测站k、g分别为3．00、2．90d^-1；27测站分别为1．94、0．91d^-1。说明厦门海域作为典型的亚热带港湾，具有高的k、g值。分粒级研究结果显示：8月，18测站微型浮游动物对微型浮游植物(Micro)具摄食偏好；而27测站微型浮游动物对Micro和Nano级的摄食率相近。应用流式细胞技术研究18测站微微型真核浮游植物的k、g，结果表明：春季，生长率和摄食率分别为2．00、1．02d^-1；夏季分别为1．52、0．96d^-1。

Grazing pressure of microzooplankton on phytoplankton in Xiamen Waters

Phytoplankton growth rate and microzooplankton grazing rate were estimated in Xiamen Waters using dilution method. In spring, phytoplankton growth rate (k) and microzooplankton grazing rate (g) were 2.41d~(-1)0.78 d~(-1), respectively, at station 18, Western Xiamen Waters, and kg were 2.43 d~(-1)1.32 d~(-1), respectively, at station 27 which represents Southern Xiamen Waters. In spring, kg were 3.00 d~(-1)2.90 d~(-1), respectively, at station 18, kg were 1.94 d~(-1)0.91d~(-1), respectively, at station 27.It shown that Xiamen Waters is the typical subtrophical water with high kg values. Size-fractionated results show that in summer microzooplankton have a preferential grazing on microphytoplankton at station 18, but was not at station 27. Picoeukaryotes were counted by a flow cytometry before and after dilution incubation and kg values at station 18 were estimated (2.00) d~(-1)1.02 d~(-1) for spring and 1.52 d~(-1)0.96 d~(-1) for summer.