Nitrogen cycle
‘Black’ nitrogen can form without fire
Open access · cc by · source: Europe PMC
Twelve-year outdoor oxidation of pine around iron nails produced condensed aromatic nitrogen like ‘black N’, implying non-fire ConAN fluxes (≈3–63 Tg yr−1) comparable to pyrogenic estimates.
Study at a glance
- Design
- Other — Spectroscopic characterization of 12-year outdoor iron-nail pine oxidation plus global ConAN budget
- N
- Case study of pine deck oxidation; flux estimates are back-of-envelope budgets, not a sample N
- Population
- Condensed aromatic nitrogen formed in outdoor-oxidized pine (Norfolk, VA) and global litter fluxes
- Outcome
- Nonpyrogenic vs pyrogenic ConAN flux estimates to soils
Structured fields used in claim comparison tables when every cited study has a complete layer.
Key findings
Oxidation built ConAC and ConAN without combustion and raised δ15N the way fire does. They estimate pyrogenic ConAN at 2–17 Tg yr−1 versus nonpyrogenic 3–63 Tg yr−1, so much ‘black N’ may not be from wildfire.
Methodology
Authors characterized blackened pine around 12-year-old iron nails (a Fenton-like outdoor oxidation reactor) with elemental, isotopic, spectroscopic, and FT-ICR-MS methods, then combined rates with global litter fluxes for a back-of-envelope ConAN budget.
Limitations
A deck-nail reactor is not all soils; the 3–63 Tg range is a first approximation using assumed ConAC formation rates and C/N ratios, not a direct global ConAN inventory.
How this study connects
Role on claims
Each row is a claim on a concept or method page where this paper supports, challenges, or qualifies the statement. Roles are hand-checked — not a model guess.
This library holds 6 empirical papers on nitrogen cycle with measured outcomes rather than reviews.
Evidence for the claim as stated.
Twelve-year outdoor oxidation of pine around iron nails produced condensed aromatic nitrogen like ‘black N’, implying non-fire ConAN fluxes (≈3–63 Tg yr−1) comparable to pyrogenic estimates.
Evidence for the claim as stated.
A reactor microbiome or a canopy 15N tracer is not catchment-scale load.
Evidence for the claim as stated.
Open questions
Tensions this paper is part of
From concept pages' “where studies disagree.” Disagreement means the same question; scope means different assays, populations, or outcomes.
A reactor microbiome or a canopy 15N tracer is not catchment-scale load.
Related papers in this topic
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