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We measured the N-15 natural abundance values of 320 individuals belonging to 45 different plant species of the Brazilian cerrado. We also determined delta(15)N of soil nitrogen as a function of soil depth. Our purpose was to test the hypothesis that N-limited cerrado would have a large range of plant delta(15)N values, similar to patterns seen in northern high-latitude ecosystems. Foliar delta(15)N values did demonstrate the large range found in some other N-limited ecosystems, varying from -5parts per thousand to +7.9parts per thousand, Significant variability within individual species was also seen across cerrado community types. Several factors contributed to this variability, including the presence of N-fixing legumes, associations with mycorrhizal fungi, delta(15)N variability of soil organic matter with depth, fire events, and the seasonality of N-immobilization and mineralization processes in cerrado soils

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