台湾海峡南部夏季微型浮游动物对不同色素类群浮游植物的摄食压力

摘要

Pigment-based growth rates of phytoplankton and mortality rates due to microzooplankton grazing were estimated using a dilution method combined with high-performance liquid chromatography (HPLC) pigment analysis at four different stations in the south Taiwan Strait in July 2005. The growth rates and mortality rates of taxon-specific pigment groups of phytoplankton were 0.52~1.34d-1 and 0.25~1.10 d-1 respectively and the grazing impact of microzooplankton on the standing stocks and primary productions of taxon-specific pigment groups were 22%~66% and 40%~l 51%, respectively. According to the g/k ratio analysis, the net growth rates of the larger phytoplankton groups (ditoms and dinoflagellates) were higher than those of smaller groups (cyanobacteria, cryp-tophytes and prymnesiophytes), suggesting that the smaller phytoplanktons were more readily controlled by microzooplankton grazing.%2005年7月在台湾海峡南部4个站位应用“稀释法”结合高效液相色谱(HPLC)色素分析技术研究了不同色素类群浮游植物的生长率及微型浮游动物对其的摄食死亡率.结果表明,不同色素类群浮游植物的生长率(k)和摄食死亡率(g)分别为0.52～ 1.34 d-1和0.25 ～ 1.10 d-1,微型浮游动物对不同色素类群浮游植物的现存量和初级生产力的摄食压力分别为22％～ 66％和40％～ 151％.通过比较不同类群浮游植物的g/k值,发现颗粒较大的浮游植物(硅藻和甲藻)的净生长率要大于那些微型藻类(蓝细菌、隐藻和定鞭金藻等)的净生长率,说明本次研究中微型藻类更易受到微型浮游动物的摄食控制.