Understanding the relationship of stable isotope ratios between polished rice and ambient water provides important strategies for tracing the geographical origin of rice. To identify the correlation of stable isotopic ratios between polished rice and ambient water, oxygen, hydrogen and carbon stable isotopes were examined in ambient water from the Tsugaru plain, Aomori prefecture. The
δ18O and
δD values of ambient water samples in the central area of the Tsugaru plain were enriched more than that of the rim of the plain. The slope of the regression equation for the meteoric water line of ambient water samples, 4.95, indicates that the sampled water in the central area of the plain was affected by evaporation. The
δ18O values of polished rice correspond with that of ambient water samples. Thus, the stable isotopes appear to have information about the geographical origin of rice. The
δ13C values of ambient water have correlations with pH, indicating the possibility that the
δ13C values depends on the mol ratios of dissolved inorganic carbons. The
δ13C values of polished rice have no correlation with ambient water samples, which may indicate that the carbon stable isotope are almost all supplied from the atmosphere.
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