title: Two categories of c/c ratios for higher plants.
abstract: (13)C/(12)C ratios have been determined for plant tissue from 104 species representing 60 families. Higher plants fall into two categories, those with low delta(PDBI) (13)C values (-24 to -34 per thousand) and those with high delta (13)C values (-6 to -19 per thousand). Algae have delta (13)C values of -12 to -23 per thousand. Photosynthetic fractionation leading to such values is discussed.
authors.affiliation: Division of Geological Sciences, California Institute of Technology, Pasadena, California 91106.
authors.forename: B N
authors.initials: BN
authors.lastname: Smith
authors.forename: S
authors.initials: S
authors.lastname: Epstein