升温对丛生盔形珊瑚两种形态型代谢和共生藻光合生理的影响

Effects of warming on the metabolism and photosynthetic physiology of the symbiotic algae of two morphological types of Galaxea fascicularis

文章研究了温度升高对一种造礁石珊瑚——丛生盔形珊瑚(Galaxea fascicularis)的两种形态型(H和S型)代谢和共生藻光合生理的影响。研究显示H型和S型对升温的生理响应差异明显:在虫黄藻水平上,H型丢失了大量的虫黄藻,减轻了共生体呼吸代谢的负荷;S型中虫黄藻数目尚可维持共生体呼吸代谢的需求,同时提高叶绿素b含量增强光的吸收。在宿主水平上,H型充分利用虫黄藻输送的营养物质,并通过异养摄食补偿能量消耗;S型宿主所储存的营养物质可以协助共生体适应热环境。结果表明,丛生盔形珊瑚两种形态型通过不同的能量利用方式适应环境的变化,H型倾向于维持共生体的代谢平衡,而S型倾向于提高共生藻的能量分配。

The effects of warming on the metabolism and photosynthetic physiology of symibiodiniaceae of two morphological types(H and S)of a reef-building coral,Galaxea fascicularis,were studied.The results showed that the physiological responses of H-type and S-type to warming were clearly different.At the symibiodiniaceae level,H-type lost a large number of symibiodiniaceae,and reduced the burden of respiratory metabolism of symbionts.In S-type,the number of zooxanthellae could still maintain the needs of symbionts for respiratory metabolism,while increasing the content of chlorophyll b to enhance light absorption.At the host level,the H-type made full use of nutrients delivered by zooxanthellae and compensated for energy consumption through heterotrophic feeding.The nutrients stored by the S-type host could assist the symbionts to adapt to the thermal environment.Galaxea fascicularis adapted itself to environmental changes through different energy utilization modes,i.e.,H-type tended to maintain the metabolic balance of the symbiont,while S-type intended to improve the energy distribution of symbiotic algae.