Re-evaluation of gross primary production and respiration in coastal aquatic ecosystems based on water quality measurements of concentrations and stable isotopes

利用传统的二氧化碳系统(CO2系统)参数和溶解氧(DO)测量以及三重氧同位素技术，测量了夏季和冬季珊瑚礁、海草草甸和红树林的呼吸作用和水中的总第一性生产力，这是亚热带和热带海岸带的特征。从获得的结果中，我发现在灯光下的呼吸频率比在黑暗中高出几十个百分点到两个百分点。这表明，基于CO_2系统和/或DO方法计算的总初级生产力和总呼吸对这些参数估计不足。夏季呼吸强度也高于冬季。但研究表明，作为计算总初级生产力的基础的“光合作用异常”可能是错误的或可变的，我们应该进一步研究这个参数，以便能够更准确地计算呼吸作用和总初级生产力。

I measured respiration and gross primary productivity in the water during summer and winter period using conventional carbon dioxide system(CO_2 system) parameters and dissolved oxygen(DO) measurements as well as triple oxygen isotope technique in a coral reef, seagrass meadow, and mangrove forest which characterize subtropical and tropical coastal zones. From the results obtained, I revealed that the respiration rate was higher by tens of percent to two-hold in the light compared with in the dark. This indicates that the gross primary production and gross respiration calculated based on CO_2 system and/or DO methods give underestimations on these parameters. The respiration was also higher during summer than winter. But it was revealed that the'' photosynthetic anomaly'' which is used as a basis for calculating gross primary productivity can be incorrect or variable, and that we should further investigate this parameter to be able to calculate the respiration and gross primary production more accurately.