Schrameyer Verena, Wangpraseurt Daniel, Hill Ross, Kühl Michael, Larkum Anthony W D, Ralph Peter J
Plant Functional Biology and Climate Change Cluster, School of the Environment, University of Technology, Sydney, Ultimo, New South Wales, Australia.
Plant Functional Biology and Climate Change Cluster, School of the Environment, University of Technology, Sydney, Ultimo, New South Wales, Australia; Centre for Marine Bio-Innovation and Sydney Institute of Marine Science, School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, New South Wales, Australia.
PLoS One. 2014 Oct 31;9(10):e110814. doi: 10.1371/journal.pone.0110814. eCollection 2014.
The light dependency of respiratory activity of two scleractinian corals was examined using O2 microsensors and CO2 exchange measurements. Light respiration increased strongly but asymptotically with elevated irradiance in both species. Light respiration in Pocillopora damicornis was higher than in Pavona decussata under low irradiance, indicating species-specific differences in light-dependent metabolic processes. Overall, the coral P. decussata exhibited higher CO2 uptake rates than P. damicornis over the experimental irradiance range. P. decussata also harboured twice as many algal symbionts and higher total protein biomass compared to P. damicornis, possibly resulting in self-shading of the symbionts and/or changes in host tissue specific light distribution. Differences in light respiration and CO2 availability could be due to host-specific characteristics that modulate the symbiont microenvironment, its photosynthesis, and hence the overall performance of the coral holobiont.
利用氧气微传感器和二氧化碳交换测量方法，研究了两种石珊瑚的呼吸活动对光的依赖性。在这两个物种中，随着光照强度的升高，光呼吸均强烈增加，但呈渐近趋势。在低光照条件下，鹿角杯形珊瑚的光呼吸高于十字牡丹珊瑚，这表明在依赖光的代谢过程中存在物种特异性差异。总体而言，在实验光照范围内，十字牡丹珊瑚的二氧化碳吸收速率高于鹿角杯形珊瑚。与鹿角杯形珊瑚相比，十字牡丹珊瑚的藻类共生体数量是其两倍，总蛋白生物量也更高，这可能导致共生体的自我遮荫和/或宿主组织特定光分布的变化。光呼吸和二氧化碳可用性的差异可能归因于宿主特异性特征，这些特征调节共生体微环境、其光合作用，进而影响珊瑚共生体的整体性能。
