A global dataset of terrestrial biological nitrogen fixation
- Carla R. Reis Ely
- Steven S. Perakis
- Cory C. Cleveland
- Duncan N. L. Menge
- Sasha C. Reed
- Sarah A. Batterman
- Timothy E. Crews
- Katherine A. Dynarski
- Maga Gei
- Michael J. Gundale
- Sarah E. Jovan
- Sian Kou-Giesbrecht
- Mark B. Peoples
- Emilio Rodríguez-Caballero
- Verity G. Salmon
- Fiona M. Soper
- Anika P. Staccone
- Benton N. Taylor
- Bettina Weber
- Nina Wurzburger
2025-08-05
Biological nitrogen fixation (BNF) is the main natural source of new nitrogen inputs in terrestrial ecosystems, supporting terrestrial productivity, carbon uptake, and other Earth system processes. We assembled a comprehensive global dataset of field measurements of BNF in all major N-fixing niches across natural terrestrial biomes derived from the analysis of 376 BNF studies. The dataset comprises 32 variables, including site location, biome type, N-fixing niche, sampling year, quantification method, BNF rate (kg N ha −1 y −1 ), the percentage of nitrogen derived from the atmosphere (%N dfa ), N fixer or N-fixing substrate abundance, BNF rate per unit of N fixer abundance, and species identity. Overall, the dataset combines 1,207 BNF rates for trees, shrubs, herbs, soil, leaf litter, woody litter, dead wood, mosses, lichens, and biocrusts, 152 herb %N dfa values, 1,005 measurements of N fixer or N-fixing substrate abundance, and 762 BNF rates per unit of N fixer abundance for a total of 424 species across 66 countries. This dataset facilitates synthesis, meta-analysis, upscaling, and model benchmarking of BNF fluxes at multiple spatial scales.