Carbon isotopes as proof for plant uptake of organic nitrogen: Relevance of inorganic carbon uptake

摘要

Ten years ago the paper of N?sholm and co-workers (N?sholm et al., 1998) renewed the discussion of the 60ties (e.g. [Birt and Hird, 1958], [McKee, 1962], [Borstlap, 1974] and [Fokin et al., 1993]) about direct uptake of organic nitrogen (N) by plants. Thereafter, an increasing number of studies were pointed on the possibility of direct uptake of organic N sources (mainly amino acids) by plants in various ecosystems.