Back to Search
Start Over
Un possible compromis entre la disponibilité de l'azote dans le sol et les entrées de carbone des racines vers le sol
- Source :
- International conference "Food security and climate change: 4 per 1000 initiative new tangible global challenges for the soil", International conference "Food security and climate change: 4 per 1000 initiative new tangible global challenges for the soil", Jun 2019, Poitiers, France
- Publication Year :
- 2019
- Publisher :
- HAL CCSD, 2019.
-
Abstract
- National audience; The potential of agricultural soils to store carbon (C) has been claimed to require a large amount of nitrogen (N) and therefore a high soil N availability. This assumption is based on the observation that stable soil organic compounds are characterized by a narrow range in C:N ratios. However, N-fertilizer additions have also been shown to increase respiratory C losses from soils. Furthermore, most of the organic C naturally stored in soils originate from plant C inputs, which occur both by aerial litter deposition and by root turnover and rhizodeposition. Root C inputs have been shown to contribute 2-3 times more to soil C sequestration than shoot-derived C inputs. However, root C inputs may be limited or even decrease when soil N availability increases beyond a certain level. A trade-off may therefore exist between the amount of soil available N and the potential of soil C sequestration associated to the inputs of root C. The existence of such trade-off and its possible consequences for the optimization of soil C sequestration will be discussed according to evidences from scientific literature and to a modelling approach describing how root C inputs to soil can evolve with soil N availability.
- Subjects :
- [SDV]Life Sciences [q-bio]
[SDE]Environmental Sciences
Subjects
Details
- Language :
- English
- Database :
- OpenAIRE
- Journal :
- International conference "Food security and climate change: 4 per 1000 initiative new tangible global challenges for the soil", International conference "Food security and climate change: 4 per 1000 initiative new tangible global challenges for the soil", Jun 2019, Poitiers, France
- Accession number :
- edsair.dedup.wf.001..1840e951c8c7855018548bf60ed72f9b