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Razanamalala K., Fanomezana R. A., Razafimbelo T., Chevallier Tiphaine, Trap Jean, Blanchart Eric, Bernard Laetitia. (2018). The priming effect generated by stoichiometric decomposition and nutrient mining in cultivated tropical soils : actors and drivers. Applied Soil Ecology, 126, p. 21-33. ISSN 0929-1393.

Titre du document
The priming effect generated by stoichiometric decomposition and nutrient mining in cultivated tropical soils : actors and drivers
Année de publication
2018
Type de document
Article référencé dans le Web of Science WOS:000428332500003
Auteurs
Razanamalala K., Fanomezana R. A., Razafimbelo T., Chevallier Tiphaine, Trap Jean, Blanchart Eric, Bernard Laetitia
Source
Applied Soil Ecology, 2018, 126, p. 21-33 ISSN 0929-1393
The priming effect (PE) in soil, when induced by a fresh carbon supply, is believed to result from two different mechanisms, "stoichiometric decomposition" and "nutrient mining", and contributes to either long-term SOM stabilization or depletion. Understanding how to affect the balance between both mechanisms can provide valuable insight into agroecology, especially in Southern countries where organic matter management is the primary method of fertilizing cultivated plots. Therefore, the objective of this study was to investigate the bacterial actors in each mechanism and the influence of three drivers in Malagasy Ferralitic soils: the quality of the inducing substrate, the quality of the SOM, and the soil nutrient status. Three different agricultural Ferralitic soils, characterized by different levels of NH4 and PO4 availability, different SOM size fractionation profiles, and different bacterial communities, were amended with three types of C-13-labeled organic substrate (glucose, wheat residue, and rice residue) and the PE was measured at two incubation times (7 and 42 days). The results showed that a PE generated by stoichiometric decomposition was mainly induced by the polymerized fraction of crop residues, especially in soil enriched by decaying plant tissues, mineral N, and its associated decomposers guild such as Verrucomicrobia, alpha- and delta-Proteobacteria and Actinomycetes. Conversely, when this young SOM pool was reduced, the PE was mainly generated by N mining, especially when induced by soluble compounds and when N was limiting but P was available.
Plan de classement
Pédologie [068] ; Biologie du sol [074]
Description Géographique
MADAGASCAR
Localisation
Fonds IRD [F B010072668]
Identifiant IRD
fdi:010072668
Contact