# Estimating Rhizosphere Priming in European Agricultural Soils

Nicolas Breil, Bernhard Ahrens, Birgit Wild, Gustaf Hugelius, Hugues Clivot, Gwenaëlle Lashermes, Sylvain Monteux, Matti Kummu, Frida Keuper

► To cite this version:

Nicolas Breil, Bernhard Ahrens, Birgit Wild, Gustaf Hugelius, Hugues Clivot, et al. Estimating Rhizosphere Priming in European Agricultural Soils. EGU General Assembly 2025, Apr 2025, Vienna, Austria. 10.5194/egusphere-egu25-19302. [hal-05081720](https://hal.inrae.fr/hal-05081720v1)

HAL Id: hal-05081720

https://hal.inrae.fr/hal-05081720v1

Submitted on 14 Oct 2025

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Distributed under a Creative Commons Attribution 4.0 International License
# Estimating Rhizosphere Priming in European Agricultural Soils

Nicolas L. Breil, Ahrens Bernhard, Wild Birgit, Hugelius Gustaf, Clivot Hugues, Lasermes Gwenaëlle, Monteux Sylvain, Kummu Matti, and Keuper Frida

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AI 4 Soil
Health

INRAO

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- Incubation studies : potential increase in SOC respiration by up to 300% due to RPE

Cheng et al., 2003

- Largest uncertainty:
  RPE magnitude in croplands

Wang et al., 2024

MISSING: broad scale spatial & depth explicit estimate

but see: additional 40 Gt C loss by 2100 from permafrost area, Keuper, Wild et al. 2020

We do not know how much the RPE contributes to Rh
# PrimeSCale model

**Method I :** assuming RPE is included in Rh

<figure><img src="image_4.png" /></figure>

RPE SOC loss (gC m⁻² yr⁻¹)

RPE SOC loss

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Uncertainty

<figure><img src="image_6.png" /></figure>

## First results

- RPE mainly occurs in topsoil layers (0-30cm)

- RPE estimated at 19(±25) gC m⁻² yr¹ (Method I)

- RPE estimated at 26(±67) gC m⁻² yr¹ (Method II)

- RPE ≈ 10% of Rh

## Assumptions

- RPE includes the mineralisation of residues

- No seasonal variation in RPE ratio