Plant δ15N values along a fog gradient in the Atacama Desert, Chile

The Atacama Desert is characterized by a fog zone occurring between 500 and 800m elevation. We hypothesized that atmospheric deposition from marine sources was the primary source of nitrogen for plants in the fog zone, and so the δ 15 N of plants should differ between those above and below that zone. No significant differences in leaf δ 15 N values were detected among the three locations. The δ 15 N values for non-nitrogen fixing species (6–12‰) were substantially more positive than that of atmospheric deposition (−1‰) suggesting immediate assimilation of nitrogen from fog was not an important source of plant nitrogen.