The combination of residue quality, residue placement and soil mineral N content drives C and N dynamics by modifying N availability to microbial decomposers

Archive ouverte : Article de revue

Chaves, Bruno | Redin, Marciel | Giacomini, Sandro José | Schmatz, Raquel | Léonard, Joël | Ferchaud, Fabien | Recous, Sylvie

Edité par HAL CCSD ; Elsevier

International audience. Crop residues are the main source of carbon (C) inputs to soils in cropping systems, and their subsequent decomposition is crucial for nutrient recycling. The interactive effects of residue chemical quality, residue placement and soil mineral nitrogen (N) availability on carbon and N mineralization dynamics were experimentally examined and interpreted using a modelling approach with the deterministic-functional, dynamic decomposition module of the Simulateur mulTIdisciplinaire pour les Cultures Standard (STICS) model. We performed a 120-day incubation at 25 °C to evaluate how the mineralization of C and N from residues would respond to residue type (residues of 10 crop species with C:N ratios varying from 13 to 105), placement (surface or incorporated) and initial soil mineral N content (9 or 77 mg N kg−1 dry soil). A reduced C mineralization rate was associated with N limitation, as observed for high-C:N ratio residues, and shaped by residue placement and initial soil mineral N content. This was not observed for low-C:N ratio residues. Overall, increased net N mineralization corresponded with reduced N availability. Using the optimization procedure in the STICS decomposition module to explain the C and N dynamics of surface-decomposing residues, we estimated that 24% of the total soil mineral N would be accessible to decomposers. The STICS decomposition module reproduced the C and N dynamics for each treatment well after five parameters were optimized. The optimized values of the biomass C:N (CNbio), residue decomposition rate (k), humification coefficient of microbial C (h), and microbial decomposition rate (λ) were significantly correlated with total N availability across all 40 treatments. Under low total N availability, CNbio increased, while k, h and λ decreased compared to their values under high N availability, suggesting functional changes in the microbial community of decomposers. Our results show that an N availability approach could be used to estimate residue C dynamics and net N mineralization in the field in response to crop residue quality and placement and demonstrate the potential to improve decomposition models by considering the effects of N availability on C dynamics.

Consulter en ligne

Suggestions

Du même auteur

An Overview of litter decomposition in soils for a diversity of agronomic a...

Archive ouverte: Poster de conférence

Jacqueton, Céline | 2021-08-23

International audience

Residual correlation and ensemble modelling to improve crop and grassland m...

Archive ouverte: Article de revue

Sándor, Renáta | 2023-01-13

International audience. Model calibration Residual plot analysis rotations including fallow periods. We do that by exploring the correlation of model residuals. We restricted the distinction between partial and full...

Ensemble modelling of carbon fluxes in grasslands and croplands

Archive ouverte: Article de revue

Sandor, Renata | 2020

International audience. Croplands and grasslands are agricultural systems that contribute to land-atmosphere exchanges of carbon (C). We evaluated and compared gross primary production (GPP), ecosystem respiration (...

Du même sujet

Miscanthus x giganteus culture on soils highly contaminated by metals: Mode...

Archive ouverte: Article de revue

Al-Souki, Karim-Suhail | 2020

ACL. Miscanthus x giganteus is suggested as a good candidate for phytostabilization of metal-polluted soils. Its late harvest in winter generates large amounts of leaf litter on the soil surface. However, little is ...

Exposure to multiple air pollutants and the incidence of coronary heart dis...

Archive ouverte: Article de revue

Occelli, Florent | 2020

ACL. Geographical variations in cardiovascular disease rates have been linked to individual air pollutants. Investigating the relation between cardiovascular disease and exposure to a complex mixture of air pollutan...

Residential exposure to outdoor air pollution and adult lung function, with...

Archive ouverte: Article de revue

Havet, Anaïs | 2020

ACL. Although a growing body of evidence suggests that chronic exposure to outdoor air pollution is linked to a decline in lung function, data on flow at low lung volumes that may be more specific of small airway ob...

An Overview of litter decomposition in soils for a diversity of agronomic a...

Archive ouverte: Poster de conférence

Jacqueton, Céline | 2021-08-23

International audience

Accumulation, speciation and localization of silver nanoparticles in the ea...

Archive ouverte: Article de revue

Courtois, Pauline | 2020-04-08

International audience. The use of silver nanoparticles (AgNPs) in agriculture and many consumer products has led to a significant release of Ag in the environment. Although Ag toxicity in terrestrial organisms has ...

Exposition aux poussières sédimentées dans les environnements intérieurs

Archive ouverte: Rapports

Glorennec, Philippe | 2019

OS. L’Agence nationale de sécurité sanitaire de l’alimentation, de l’environnement et du travail endosse les conclusions et recommandations de l’expertise collective relative à la caractérisation de l’exposition de ...

Chargement des enrichissements...