Deanne C. Drake, Robert J. Naiman, and J. Scott Bechtold. 2006. Fate of nitrogen in riparian forest soils and trees: an ¹⁵N tracer study simulating salmon decay. Ecology 87:1256–1266.

Appendix B. A figure showing ¹⁵N tracer maxima in extractable and microbial soil pools.

FIG. B1. Percentage of tracer N recovered from the extractable N pools in the organic soil horizon () and the mineral horizon (). 15N tracer maxima in both extractable (A) and microbial (B) pools occurred later in mineral soils, demonstrating downward movement of the tracer N. The 15N tracer was added days 0–6.