ANALYSIS OF ENVIRONMENTAL HISTORIES OF MARINE LIVES USING IT'S BIO-MINERALS

点击翻译按钮获取中文摘要

(1) Scale circuli of red sea bream Pagrus major were counted to investigate the relation between circuli deposition and seawater temperature. The samples were collected from several stations indicated different temperature fluctuation. The daily deposition rate depended on their scale growth rate in accordance with their body growth since the circuli numbers were linearly proportional to their fork length.(2) Trace element concentration in red sea bream otoliths by particle induced X-ray emission, PIXE.Otoliths were collected from the juveniles reared at several stations indicated different temperature fluctuation. Otolith surfaces without cutting or polishing were exposed to a proton beam. X-ray spectra detected with a litium-drift silicon detector indicated that the otoliths contained several trace elements of 2+ valence such as Mn (40-64ppm), Fe (169-246ppm), zn (61-120ppm), and Sr (1634-2330ppm). The concentrations seemed to increase in proportion to temerature.(3) Japanese short-necked clams Tapes philippinarum were cultivated under three different immersed conditions then growth band patterns in the shell were statistically compared. The group A was immersed except at semi-diurnal low tide, group B was out in-air at lowest sea level in high tide and group C was kept always below sea surface throughout the experiment. No numerical difference was found in the growth band number among the groups. All clams subjected to a 66 minutes period seich in the band as well as semi-diurnal and diurnal tidal period.