Carbonate system dynamics in coral reef

(1)对静子-硫马岛珊瑚礁的碳酸盐体系组成进行了5年的系统观测。海水PCO2具有白天低、夜间低的典型日变化规律，反映出白天高光合作用、高钙化、夜间高呼吸速率的特点。(2)考虑到珊瑚礁水域的水流特征，成功建立了动态Box模型，计算了珊瑚礁的碳酸盐体系组分变化，解释了珊瑚礁CO2的日变化。(3)珊瑚礁PCO2变化的频率分析表明，珊瑚礁PCO2的主要变化频率为26.7小时，这可能是月球系统控制珊瑚礁CO2的可能机制。除短期变化外，长期变化还表现为月阻塞变化，并形成季节变化。珊瑚礁碳酸盐体系长期变化的数值分析对于验证珊瑚礁碳酸盐体系变化与全球环境变化的关系具有重要意义(5)。本研究开发的Dynamic Box模型被成功地应用于留尼汪岛珊瑚礁碳酸盐体系。(6)如上所述，本研究成功地建立了珊瑚礁碳酸盐体系变化评价的基本方法。

(1).Carbonate system components are systematically observed for 5 years at coral reef of Sesoko-jima Island. PCO2 in sea water showed typical diurnal patterns : low in daytime and low in night time, which reflected the high photosynthesis and calcification in daytime, and high respiration rate at night time.(2).Considering the water flow in reef area, dynamical Box model was successfully constructed in order to calculate the carbonate system component variation and to explain the diurnal PCO2 variation in coral reef.(3).Frequency analysis of PCO2 variation in coral reef revealed that the main variation frequency was 26.7 hours, which suggested the possible mechanism of lunar system to control PCO2 in coral reef. Another frequencies variation such as 13 or 6.5 hours are also found.(4).Eliminating the short term variations, longer term variation of PCO2 also showed monthly blockage change of PCO2 and forms seasonal variation. Numerical analysis of long term PCO2 variation is important to verify the relationship between carbonate system variation in coral reef and the global environmental change(5).Dynamical Box model developed in this study is successfully applied to the carbonate system of Re-Union coral reef.(6).As shown above, fundamental methods to evaluate the carbonate system variation in coral reef are successfully established in this research project.