STUDIES ON CONSERVATION OF LOCAL CORAL COMMUNITIES UNDER THE PROGRESSIVE GREEN HOUSE EFFECT

1.冲绳岛周围珊瑚群落的恢复：在冲绳岛中西海岸的珊瑚礁上建立的10个站点监测了1998年发生大规模珊瑚漂白后珊瑚群落的恢复过程。每个站点都设置了珊瑚幼虫安置板，收集后对安放的珊瑚进行检查。还在每个站点进行了珊瑚群落调查。成熟的Acropora殖民地很少，但在靠近Kerama岛的站点招募Acropora的人数很多。这表明，角马群岛的珊瑚种群是冲绳岛珊瑚群落恢复的珊瑚幼虫的来源。琉球群岛珊瑚种群遗传学：冲绳岛、鹿儿岛和石垣岛珊瑚种群的基因流动。用等位酶电泳法对8种珊瑚进行了研究。八种珊瑚中的三种也进行了估计珊瑚幼虫定居适宜期的实验室实验。在具有较长定居能力周期的物种(散布产卵的珊瑚，如Acropora diditifera)方面，三个地区之间的基因流动程度相似，但冲绳群岛之间的基因流动程度更大。而科拉玛就是。在栖息期较短的物种上，冲绳-龟山和石垣/伊里奥莫特之间的物种(浮萍繁殖珊瑚，如柱头珊瑚)。不同珊瑚白化死亡地点间珊瑚共生虫黄藻的基因多样性：采用SSCP方法对1998年3个不同程度的珊瑚漂白地点的6种珊瑚共生虫黄藻的基因多样性进行了比较。虫黄藻的基因多样性在珊瑚因漂白而死亡最低的地点最高，在珊瑚死亡最高的地点最低。

1. Recovery of coral communities around Okinawa Island: Recovery processes of coral communities after mass coral bleaching occurred in 1998 were monitored at 10 stations established on coral reefs along mid-west coast of Okinawa Island. Settlement panels for coral larvae were set at each station, and settled corals were examined after collection. Survey of coral communities was also conducted at each station. There were very few mature Acropora colonies, but recruitment of Acropora was large at stations that are located near Kerama Islands. It is suggested that coral populations at Kerama Islands are the source of coral larvae for the recovery of coral communities in Okinawa Island.2. Population genetics of coral populations in the Ryukyu Archipelago: Gene flow of coral populations among Okinawa Is., Kerama Is., and Ishigaki/Iriomote Is. was investigated in eight species of hermatypic corals by allozyme electrophoresis. Laboratory experiments to estimate settlement competency periods of coral larvae were also conducted in three of the eight coral species. The degree of gene flow was similar among the three regions in species having long settlement competency periods (broadcast spawning corals such as Acropora digitifera), but was greater between Okinawa Is. and Kerama Is. than between Okinawa-Kerama and Ishigaki/Iriomote in species having short settlement competency periods (planula brooding corals such as Stylophora pistillata).3. Genotypic diversity of coral symbiotic zooxanthellae among the sites with different coral mortality due to bleaching: Genotypic diversity of symbiotic zooxanthellae in six coral species was compared among three sites that suffered from different degree of coral bleaching in 1998 by DNA analysis using SSCP method. The genotypic diversity of the zooxanthellae was the highest at a site that suffered from the lowest coral mortality due to bleaching, and the lowest at a site that suffered from the highest coral mortality.