春季东海中华哲水蚤对有害藻华物种的选择性摄食

Selective feeding of Calanus sinicus on harmful algal blooms species in East China Sea in spring

2005年4月27日—6月5日在东海有害藻华高发区的6个典型站位采样,分析了浮游植物的群落结构,并采用现场实验研究了中华哲水蚤(Calanussinicus)的选择性摄食.结果表明,中华哲水蚤对浮游植物的选择性摄食具有食物密度依赖性.低浮游植物细胞丰度下中华哲水蚤具有明显的选择性摄食行为,高浮游植物细胞丰度下中华哲水蚤摄食选择性由偏好转变为排斥,浮游植物细胞丰度329cells.ml-1是中华哲水蚤由偏好趋于排斥摄食的阈值.中华哲水蚤的选择性摄食还与食物组成有关,对于食物中的微型浮游动物,中华哲水蚤无选择性或排斥摄食.有害藻华发生区中华哲水蚤对具齿原甲藻(Prorocentrumdentatum)的偏好摄食以及对米氏凯伦藻(Kareniamikimotoi)的排斥摄食,促使藻华的物种演替最终向米氏凯伦藻水华方向发展.

From April 27^th to June 5^th 2005, the selective feeding of Calanus sinicus on harmful algal blooms （HABs） species was studied by in situ feeding experiments at six typical stations in a high frequency red tide occurring region of East China Sea. The results showed that the selective feeding behavior of C. sinicus was dependent on food density. It had an obvious food selectivity when the abundance of phytoplankton cell was low, but the selectivity changed from preference to discrimination at high phytoplankton cell abundance, with a threshold value of 329 cells·ml^-1. The selective feeding of C. sinicus was also dependent on food composition. It showed no selective feeding or discrimination on microzooplankton at most stations, but preferred to P. delicatissima and disliked Karenia mikimotoi at HABs occurring station, which induced the succession of phytoplankton community to K. mikimotoi blooming.