Retention of deposited ammonium and nitrate and its impact on the global forest carbon sink.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 35169118.
- Also identified by DOI 10.1038/s41467-022-28345-1 and PMC identifier 8847626.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The impacts of enhanced nitrogen (N) deposition on the global forest carbon (C) sink and other ecosystem services may depend on whether N is deposited in reduced (mainly as ammonium) or oxidized forms (mainly as nitrate) and the subsequent fate of each. However, the fates of the two key reactive N forms and their contributions to forest C sinks are unclear. Here, we analyze results from 13 ecosystem-scale paired <sup>15</sup>N-labelling experiments in temperate, subtropical, and tropical forests. Results show that total ecosystem N retention is similar for ammonium and nitrate, but plants take up more labelled nitrate ([Formula: see text]%) ([Formula: see text]) than ammonium ([Formula: see text]%) while soils retain more ammonium ([Formula: see text]%) than nitrate ([Formula: see text]%). We estimate that the N deposition-induced C sink in forests in the 2010s is [Formula: see text] Pg C yr<sup>-1</sup>, higher than previous estimates because of a larger role for oxidized N and greater rates of global N deposition.
Medical subject headings
- Ammonium Compounds
- Carbon Sequestration
- Environmental Restoration and Remediation
- Forests
- Nitrates
- Trees