Life-form population responses of a marine planktonic diatom,Chaetoceros pseudocurvisetus, to oligotrophication in regionally upwelled water
Life-form population responses of a marine planktonic diatom,Chaetoceros pseudocurvisetus, to oligotrophication in regionally upwelled water
复制标题
海洋浮游硅藻的生命形式种群对区域上升流水中寡营养化的反应
DOI：
10.1007/bf01313435
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发表时间：
1990
期刊：
影响因子：
2.4
通讯作者：
M. Takahashi
中科院分区：
文献类型：
--
作者：
A. Kuwata;M. Takahashi
1986年和1988年夏季，在日本伊豆群岛的区域性涌升水中，营养盐浓度从有利于活跃生长和繁殖的条件变为不利于活跃生长和繁殖的条件（寡营养化），研究了一种以浮游硅藻为中心的角毛藻（Chaetoceros pseudocurvisetus Mangin）的生活型种群响应。观察到两种类型的生命形式：健康和不健康的营养细胞和休眠孢子。观察到的生命形式的反应进行了实验评估沿着的限制营养素的耗尽。藻类种群停止营养生长，并开始休眠孢子的形成与限制硝酸盐的消失，这种生命形式的反应似乎是由细胞氮含量低于一定水平的下降触发。由于休眠孢子的形成需要大量的硅，部分营养细胞不能形成休眠孢子，而在不充足的草酸浓度下形成看起来不健康的营养细胞。在人口中的休眠孢子的百分比份额呈线性相关的可用的柠檬酸的量。没有形成休眠孢子的营养细胞表现出比休眠孢子更大的死亡率，由细菌和原生动物的攻击，然而，营养细胞可以迅速响应可能的营养补充。
Life-form population responses of a centric planktonic diatom,Chaetoceros pseudocurvisetus Mangin, were investigated in summer 1986 and 1988 in the Izu Islands, Japan, in regionally upwelled water where nutrient concentration changed from favorable to unfavorable conditions for active growth and reproduction (oligotrophication). Two types of life form were observed: vegetative cells of healthy and unhealthy looking conditions and resting spores. The observed life-form responses were experimentally evaluated along with a depletion of limiting nutrients. The algal population ceased vegetative growth and initiated resting spore formation with a disappearance of limiting nitrate, and this life-form response seemed to be triggered by the decrease of cellular nitrogen content below a certain level. Since a large amount of silicon was required for the resting spore formation, a part of vegetative cells were unable to form resting spores and formed unhealthy looking vegetative cells under insufficient concentrations of silicic acid. Percentage shares of the resting spores in the population were linearly related to the amounts of available silicic acid. Vegetative cells which did not form resting spores showed greater mortality than resting spores by attack of bacteria and protozoa; however, vegetative cells could respond quickly to possible nutrient replenishment.