珊瑚礁是热带海洋特色生态系统，具有重要的经济和生态价值，岛礁为礁区最重要的生物地貌结构，其社会和战略地位显著。全球变化不断加剧的背景下，珊瑚岛礁系统面临严重威胁。珊瑚礁生态健康和岛礁稳定安全是当前国际研究的两大热点，珊瑚礁生态演变对岛礁稳定性的影响研究则相对缺乏。本项目以造礁石珊瑚生物钙化产生碳酸盐沉积参与岛礁生物地貌过程为切入点，选择西沙群岛典型岛礁开展造礁石珊瑚群落演变及碳酸盐生产力研究，分析群落现状、历史动态及发展趋势探究造礁石珊瑚群落演变规律及环境调控机制；计算造礁石珊瑚种类钙化率和群落碳酸盐生产力并分析全球变化背景下岛礁的稳定性，阐明造礁石珊瑚群落演变对维持岛礁稳定的重要作用。该研究不仅对研究全球变化背景下南海岛礁的生态演化与动态稳定具有科学意义，而且为开发南海岛礁资源、维护海洋权益、建设海洋强国提供科技支撑。

Coral Reefs which provide a variety of valuable goods and economic services are the most typical ecosystems on the tropical oceans. Coral reef islands are the most important bio-geomorphological structure with remarkable social and strategic significance. The most serious threat from global change would bring about ecological collapse and island erosion. The health of ecosystems and stability of islands are becoming two research hotspots recently, but the lack in the implications of ecosystem change for the stability and maintenance of reef islands. This project will be focus on the biological geomorphological process involved the calcium carbonate deposits by Scleractinian corals and do some research on the coral community change and carbonate production by scleractinian corals in the Xisha Islands. The evlolution of coral community will be analysized on the basis of the data from field work, age structure of massive Porites and community dynamic model. The coral calcification and community carbonate production will be used for analysis of the importance of coral communities to the maintenance of coral reef islands. This project is not only scientific important to study the coral reef ecological evolution and stablity of Xisha islands under global change, but also provide technology support for the development of coral reef resources, maintenance of maritime rights and construction of sea power in the South China Sea.