Response of the N and P cycles of an old-growth montane forest in Ecuador to experimental low-level N and P amendments

▶ Low-level repeated N and P additions to tropical montane forest remain in the ecosystem. ▶ N and P additions reduce canopy uptake of these elements from the atmosphere. ▶ N and P additions increase internal N and P fluxes with throughfall and litterfall. ▶ N and P seem to be co-limiting canopy and organic layer organisms. ▶ Low-level N and P additions do not increase N and P concentrations in surface water at the short run.