Long-term nitrogen fertilization alters microbial respiration sensitivity to temperature and moisture, potentially enhancing soil carbon retention in a boreal Scots pine forest

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388971%3A_____%2F25%3A00640275" target="_blank" >RIV/61388971:_____/25:00640275 - isvavai.cz</a>

Result on the web

<a href="https://bg.copernicus.org/articles/22/5497/2025/" target="_blank" >https://bg.copernicus.org/articles/22/5497/2025/</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.5194/bg-22-5497-2025" target="_blank" >10.5194/bg-22-5497-2025</a>

Result language

angličtina

Original language name

Long-term nitrogen fertilization alters microbial respiration sensitivity to temperature and moisture, potentially enhancing soil carbon retention in a boreal Scots pine forest

Original language description

Nutrient availability affects microbial respiration kinetics, their sensitivities to environmental conditions, and, thus, the soil organic carbon (SOC) stocks. We examined long-term nitrogen (N) addition effects on soil heterotrophic respiration (Rh), methane (CH4) oxidation, and nitrous oxide (N2O) emissions in an N-limited boreal Scots pine (Pinus sylvestris) forest in central Finland. Measurements included the following (in both control and N-fertilized plots): long-term tree biomass monitoring (1960-2020), soil organic carbon (SOC) monitoring in 2023, monthly aboveground litterfall monitoring (2021-2023), biweekly CO2, CH4, and N2O fluxes during the 2021-2023 growing seasons, and quarter-hourly recordings of soil temperature (T) and soil water content (SWC). We assessed mean greenhouse gas (GHG) flux differences and Rh dependence on T and SWC using polynomial and nonlinear regression models.Tree biomass, litterfall, and SOC increased with long-term N fertilization. However, N fertilization also significantly increased mean Rh, reduced CH4 oxidation slightly, and modestly raised N2O emissions. SOC-normalized Rh (Rh/SOC) did not significantly differ between treatments, yet relationships between Rh/SOC and T and SWC diverged with fertilization. In control plots, Rh/SOC peaked at 15.8 degrees C, whereas it peaked at 16.8 degrees C in N-fertilized plots. Under N fertilization conditions, Rh/SOC was weakly SWC-dependent, contrasting with a distinct humped SWC response enhancing annual Rh/SOC in control plots. Annually, N-fertilized plots respired 10.3 % of SOC (+/- 0.3 SE, standard error), compared to 12.2 % (+/- 0.5 SE) in control plots, suggesting that N fertilization promoted SOC retention. Consequently, N fertilization reduced average annual net CO2 emissions by 345.4 (+/- 73.6 SE) gCO2m-2yr-1, while the combined effects on CH4 and N2O fluxes and the production energy of N fertilizer contributed a minor CO2-equivalent increase of 17.7 (+/- 0.5 SE) gCO2eq.m-2yr-1.In conclusion, long-term N fertilization in boreal forests could reduce the global warming potential of soil GHG emissions, mainly by slowing Rh/SOC and altering its responses to T and SWC, thereby enhancing SOC sequestration in addition to the increased tree biomass carbon sink.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10606 - Microbiology

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2025

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Biogeosciences

ISSN

1726-4170

e-ISSN

1726-4189

Volume of the periodical

22

Issue of the periodical within the volume

19

Country of publishing house

DE - GERMANY

Number of pages

14

Pages from-to

5497-5510

UT code for WoS article

001590571400001

EID of the result in the Scopus database

2-s2.0-105020094469