Study Reveals How Nitrogen Deposition Affects Terrestrial Ecosystem Carbon Sinks
2026-05-11
A research team led by Prof. LI Lei from the Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences has revealed new insights into nitrogen (N) deposition impacts on terrestrial ecosystem carbon sinks. The findings were published in Catena and Advanced Science on May 23, 2025, and March 25, 2026, respectively.
Nitrogen deposition, as a critical external nutrient input that alleviates ecosystem nitrogen limitation, plays an essential role in promoting carbon sink formation. Accurately quantifying the fate of deposited nitrogen is essential for reliably estimating its contribution to the global carbon sink.
To address how altered precipitation distribution affects deposited nitrogen retention and the consequent carbon sink, to estimate the contribution of deposited nitrogen to global terrestrial carbon sinks, and to reliability the accuracy of terrestrial carbon sink projections under climate change, the researchers carried out extensive experiments and analyses.
By conducting dual‑isotope (¹⁵N) tracer experiments combined with manipulated precipitation distribution patterns in the alpine grasslands of the Kunlun Mountains, the researchers quantitatively assessed the effects of altered precipitation regimes on the retention of deposited nitrogen and the associated carbon sink in this region using stoichiometric methods.
Furthermore, by compiling and analyzing 829 global ¹⁵N isotope tracer observations, the study quantified the retention of reduced N (NHₓ) and oxidized N (NOᵧ) in terrestrial ecosystems at the global scale, distinguished the allocation of deposited nitrogen between woody tissues (stems, coarse roots, branches) and non‑woody tissues (leaves, fine roots, bark), and revealed the global retention patterns of deposited nitrogen and the spatial distribution of the induced carbon sink across global terrestrial ecosystems.
The study demonstrates that altered precipitation patterns increase the risk of decline in nitrogen‑deposition‑induced carbon sinks, suggesting that current carbon sink estimates based on historical mean climatic conditions may be overestimated.
At the global scale, distinguishing nitrogen allocation between woody and non‑woody plant tissues reduces uncertainties in estimating the nitrogen‑induced carbon sink and establishes the spatial pattern of terrestrial carbon sinks promoted by nitrogen deposition, thereby providing a critical scientific foundation for global terrestrial carbon sink assessment.
Read the full article: https://doi.org/10.1016/j.catena.2025.109179
https://doi.org/10.1002/advs.202520069
Contact
LI Lei
Xinjiang Institute of Ecology and Geography
E-mail: lilei@ms.xjb.ac.cn