Early- and later-stage priming effects induced by spruce root fractions are regulated by substrate availability, stoichiometry and C input

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60077344%3A_____%2F23%3A00573916" target="_blank" >RIV/60077344:_____/23:00573916 - isvavai.cz</a>

Alternative codes found

RIV/61389005:_____/23:00573916 RIV/00216208:11310/23:10468218 RIV/60076658:12310/23:43907299

Result on the web

<a href="https://www.sciencedirect.com/science/article/pii/S0016706123002872?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0016706123002872?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.geoderma.2023.116610" target="_blank" >10.1016/j.geoderma.2023.116610</a>

Result language

angličtina

Original language name

Early- and later-stage priming effects induced by spruce root fractions are regulated by substrate availability, stoichiometry and C input

Original language description

The priming effect (PE), referring to the change in the soil organic carbon (SOC) turnover induced by fresh C input, is crucial to the SOC budget. Temperate coniferous forests store a large SOC pool that can be influenced by litter C input. Root litter is a major source of belowground C input but much less studied than leaf litter. Nowadays, it is not clear how PEs are controlled by root litter input of different availability and stoichiometry in coniferous forests and what the underlying mechanisms are. We prepared soluble fraction (SF) and insoluble fraction (IF) from 13C-depleted spruce roots using hot-water extraction and incubated these fractions with spruce forest soils (Cambisols) to measure the PE. Labile and slow C pools were simulated using a first-order parallel model, whereas soils were harvested during and after the incubation to estimate microbial utilization of substrate-C and C use efficiency (CUE). The SF had higher substrate availability, greater C:N ratio, and smaller C quantity than the IF. The PE ranged from −0.71 ± 0.44 to 3.34 ± 1.31 mg C/g SOC. The addition of SF induced an immediate and short-lasting positive PE, whereas that of IF caused a gradual and long-lasting positive PE. The immediate PE was associated with abundant, substrate-derived labile C. This indicates that the early-stage PE was controlled by substrate availability. The long-lasting PE was accompanied by an accelerated decomposition of the slow C pool, reflecting that substrate stoichiometry (C:N ratio) and total C input control the later-stage PE by regulating the decomposition of the slow C pool. This can be further explained by a shift between stoichiometric decomposition and N-mining mechanisms of the PE due to changes in CUE, microbial utilization of substrate-C, and K- vs. r-strategists with substrate C:N ratios. Regarding net C budget, a smaller C accumulation induced by the SF addition corresponded to the higher substrate availability and C:N ratio due to the greater early-stage PE and lower CUE, respectively. We propose that in our studied soils: (1) substrate availability determines the early-stage PE through substrate-derived labile C, (2) substrate stoichiometry and total C input regulate the later-stage PE through microbial utilization of substrates, and (3) both substrate availability and stoichiometry control net C budget. Our study highlighted that the shift in PEs with incubation time was regulated by substrate availability, stoichiometry, and C input at the level of the C input in natural spruce forests.

Czech name

—

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

—

OECD FORD branch

40104 - Soil science

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2023

Confidentiality

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

Name of the periodical

Geoderma

ISSN

0016-7061

e-ISSN

1872-6259

Volume of the periodical

437

Issue of the periodical within the volume

September

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

13

Pages from-to

116610

UT code for WoS article

001044027000001

EID of the result in the Scopus database

2-s2.0-85164987748