Nitrogen fixation may not alleviate stoichiometric imbalances that limit primary production in eutrophic lake ecosystems.

ABSTRACT: Ecosystem-scale primary production may be proximately limited by nitrogen (N) but ultimately limited by phosphorus (P) because N₂ fixation contributes new N that accumulates relative to P at ecosystem scales. However, the duration needed to transition between proximate N limitation and ultimate P limitation remains unknown for most ecosystems, including lakes. Here we present the results of a fully replicated, multi-annual lake mesocosm experiment that permitted full air-water-sediment interactions that mimicked lake ecosystem ecology. We manipulated N supply relative to P to achieve a gradient of N:P stoichiometry. Despite N₂ fixation contributing as much as 80% of reactive N in the low N treatments, phytoplankton biomass in these treatments was not different from th

SUBMITTER: Andersen IM 

PROVIDER: S-EPMC11758711 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature