Reef growth and the Late Holocene climatic change recorded in the Raised Coral Reef in Kikai-jima Islands, Ryukyu, Japan.

1996年和1997年，在日本西南部琉球岛菊海岛北海岸的七道谷附近，对全新世凸起珊瑚礁和现今珊瑚礁进行了实地考察。6个岩心样品（T-1-T-6），长度为2.44 ~ 3.99 min，直径为5 cm。在II ~ iv梯田上，在两性珊瑚组合中以板状和包覆的鹿角类为主，如a.h acacinthus、a.d efera、a.g emifera和A.monticulosa。物种组合表明，所有岩心均沉积于0 ~ 10 min深度的浅海环境中。在Shido-oke礁坡上，从0 ~ 30 min深度每隔5 m采集活的Porites类、Tridacna类的骨骼和海水样本。在实验室拍摄了活珊瑚和全新世珊瑚板的软x射线照片，并研究了样品的年生长带。活样（KS01-09）采自9 min深度。化石样本（1805）的使用年龄比Ota et al.（1998）晚9.2 ka。用质谱法测定了珊瑚骨架的碳、氧稳定同位素比值。利用IGOSS海温资料和JODC的1 mesh盐度资料，分别重建了菊海岛海域的海温和月平均盐度。根据氧同位素异常模型，包括生命效应和冰盖大小，估算了纪开岛周围古海温和现在海温。预测当前平均海温为21.9 C，比实测数据低2.6 C。早全新世平均海温为22.0 C，这与利用传递函数计算的结果不一致。

Field surveys on the Holocene Raised Coral Reef and present coral reefs around Shido-oke in the northern coast of Kikai-jima Island, Ryukyus, southwest Japan were carried out in 1996 and 1997. Six core samples (T-1-T-6) ranging from 2.44 to 3.99 min length and 5 cm in diameter were obtained by using hand corer which was equipped by this Grant. on the Terraces II to IV.Tabular and encrusting Acropora, such as A.hyacinthus, A.digitifera, A.gemmifera, and A.monticulosa predominate in the hermatypic coral assemblages. Species combination indicates that the all cores were deposited in the shallow marine environments from 0 to 10 min depth. Skeletons of the living Porites spp., Tridacna spp. and sea water samples were collected from every 5 m from 0 to 30 min depth on the reef slope off Shido-oke.SoftX-ray photos of the living and Holocene coral slabs were taken in the laboratory and the annual growth bands were studied to date the samples. The living (KS01-09) sample was taken from 9 min depth. Useries age of the fossil sample (1805) is 9.2 ka after Ota et al.(1998). Carbon and oxygen stable isotope ratios of the coral skeleton were measured by the mass spectrometry. Present sea surface temperature (SST) and monthly mean salinity around Kikai-jima Island are reconstructed from IGOSS SST data and 1ﾟ mesh salinity data of JODC,respectively.Paleo- and present SSTs around Kikai-jima were estimated according to the oxygen isotope anomaly model including the vital effects and the ice sheet size. It predicts that-the present mean SST is 21.9ﾟC,2.6ﾟC lower than the actually measured data. Early Holocene mean SST was also estimated to be 22.0ﾟC,which is discordant with the results calculated on the transfer function..