Extraction of paleoenvironmental records from terrestrial laminated carbonates such as speleothems and tufa deoosits

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Past environmental information has been extracted from terrestrial laminated carbonates such as speleothems in limestone caves and tufa deposits in karst surface streams as follows : i) It was possible to determine the absolute age using microscopic fluorescent annual layers of the carbonates. ii) The historical anthropogenic vegetation change from forest to grassland on Akiyoshi-dai karst plateau, Yamaguchi was confirmed using the carbon isotope ratios and the concentration of trace elements such as Mg in stalagmites. iii) The unusual high activities of ^<137>Cs in tufa deposits on Hirao-dai karst plateau, Kitakyushu were due to the global fallout of the atomic bombs and the tests of nuclear weapons in the atmosphere. iv) It is clarified that long-range transport of acid depositions from the Asian Continent has been clearly observed in a stalagmite and a pine tree on Iriomote Is., the Ryukyus, since 1980's. v) The δ^<18>O geothermometer data have been compiled using samples collected from different temperature areas in Japan.