Above-ground tree carbon storage in response to nitrogen deposition in the U.S. is heterogeneous and may have weakened
Changes in nitrogen (N) availability affect the ability for forest ecosystems to store carbon (C). Here we extend an analysis of the growth and survival of 94 tree species and 1.2 million trees, to estimate the incremental effects of N deposition on changes in aboveground C (dC/dN) across the contiguous U.S. (CONUS). We find that although the average effect of N deposition on aboveground C is positive for the CONUS (dC/dN = +9 kg C per kg N), there is wide variation among species and regions. Furthermore, in the Northeastern U.S. where we may compare responses from 2000-2016 with those from the 1980s–90s, we find the recent estimate of dC/dN is weaker than from the 1980s–90s due to species-level changes in responses to N deposition. This suggests that the U.S. forest C-sink varies widely across forests and may be weakening overall, possibly necessitating more aggressive climate policies than originally thought.
© The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. The Version of Scholarly Record of this Article is published in Communications Earth & Environment, 2023, available online at: https://www.nature.com/articles/s43247-023-00677-w . Keywords: carbon cycle; climate change ecology; forest ecology.
Clark, C.M., Thomas, R.Q. & Horn, K.J. Above-ground tree carbon storage in response to nitrogen deposition in the U.S. is heterogeneous and may have weakened. Commun Earth Environ 4, 35 (2023). https://doi.org/10.1038/s43247-023-00677-w