琼东上升流缓解珊瑚白化和促进恢复的生理作用机制

随着持续的全球气候变暖，升温引起珊瑚白化事件的强度和频率不断增加，严重威胁世界范围内珊瑚礁的生存。上升流区被认为是潜在的珊瑚礁高温避难所，但是琼东上升流能否为海南岛珊瑚礁提供庇护作用，还有不确定性。本项目基于剖面调查和长期观测数据资料，探讨琼东上升流对海南岛珊瑚礁区环境特征的影响程度、范围、持续时间及不同年际差异，阐明琼东上升流是否会引起珊瑚礁区域夏季水温实质性的降低；采用脉冲调制荧光技术、光合与呼吸代谢技术和稳定同位素技术等综合手段，研究琼东上升流时空变化是否会缓解珊瑚的热白化指数和生理胁迫，确立上升流引起的环境因子变化是否会促进白化珊瑚的恢复；基于室内模拟实验，研究上升流引起的温度降低和食物添加对两种白化珊瑚恢复的促进作用，探讨其生理作用机制，阐明不同珊瑚的能量获取和利用策略。研究结果有助于预测和评估海南岛珊瑚礁应对未来气候变化时的命运，为海南岛珊瑚礁的保护和管理提供科学依据。

With continuous global warming, the intensity and frequency of coral bleaching events will become a serious threat to the survival of coral reefs worldwide. The upwelling area is considered to be a potential high-temperature refuge for coral reefs, but it is still uncertain whether the Qiongdong upwelling can provide refuges for the coral reefs of Hainan Island. Based on profile surveys and long-term observation data, this project explores the extent, scope, duration and inter-annual differences of Qiongdong upwelling on the environmental characteristics of coral reefs in Hainan Island, and clarifies whether Qiongdong upwelling will cause a substantial decrease in summer water temperature in the coral reef area. By using comprehensive methods, such as fluorescence modulation technology, photosynthetic and respiratory metabolism technology and stable isotope technology, this project investigates whether spatial-temporal changes of Qiongdong upwelling will alleviate coral bleaching index and physiological stress, and will promote the recovery of bleached corals. The intrusion of low-temperature water and the addition of food from upwelling will be simulated in indoor laboratory. Thus, the physiological mechanism of promoting the recovery of two bleached corals is discussed, and the energy acquisition and energy utilization strategies of different corals are clarified. The research results are helpful to predict and assess the fate of coral reefs in Hainan Island in response to future climate change, and provide a scientific basis for the protection and management of coral reefs in Hainan Island.