Search results for "Nitrogen"
showing 10 items of 1200 documents
Caractérisation des communautés microbiennes dans les technosols construits pour la restauration des friches industrielles
2012
Increasing soil degradation and its consequences on overall ecosystem services urge for restoration strategies. Construction of Technosols through assemblage of treated soil and industrial wastes is an innovative technology for the restoration of polluted land and re-use of industrial by-products. Recent studies have evidenced that Technosols could support ecosystemic services such as primary production but the knowledge about other soil functions, such as biogeochemical cycling, is limited. Due to the significant contribution of microbial communities to soil functioning, this PhD work was carried out to study the effect of the type of Technosol on microbial communities with a focus on func…
Mapping spatial patterns of denitrifiers for bridging community ecology and microbial processes along environmental gradients
2009
International audience; While there is ample evidence that microbial processes can exhibit large variations at a field scale, very little is known about the spatial distribution of the communities mediating these processes. The objective of this study was to explore spatial patterns of size and activity of the denitrifying community, a functional guild involved in N-cycling, in a grassland field subjected to different cattle grazing regimes. We used geostatistical modeling to map the distribution of size and activity of the denitrifier community in the pasture. Size of the denitrifier community was estimated by PCR quantification of the denitrification gene copy numbers while its activity w…
A tale of two stories from the underground: soil microbial diversity and N cycling
2016
International audience; Dr. Laurent Philippot is Director of Research at the French Institute for Agricultural Research (INRA) and is leading a research group at the department of Agroecology in Dijon. He did a sabbatical at Georgia Tech in Atlanta and at the Swedish University of Agricultural Science (SLU) in Uppsala in 2000 and 2009, respectively. His research focuses on bridging microbial community ecology, microbial processes and ecosystem functioning using microbial guilds involved in nitrogen cycling and greenhouse gas. He is serving as Senior Editor of The ISME Journal and as editorial board member for FEMS Microbiology Ecology, Applied and Environmental Microbiology and Frontiers in…
Comment le mode de nutrition azotée influence-t-il le prélèvement, le stockage et la remobilisation des nutriments en conditions hydriques fluctuante…
2019
National audience; Pea seeds have interesting nutritional properties through their protein, vitamin and mineral contents. However, environmental conditions such as soil water availability during plant growth influence both final yield and seed quality in pea. Soil water conditions not only modulates pea nitrogen acquisition whatever the mode of nitrogen nutrition: mineral nitrogen acquisition by roots and atmospheric di-nitrogen fixation by nodules in interaction with rhizobia, but also the overall plant mineral nutrition. The aim of this study is to get a better understanding of soil water deficit impact on nutrient acquisition, storage and distribution inside the plant according to the mo…
How to model crop-weed competition for soil resources: Connecting the STICS soil submodel to the FLORSYS weed dynamics model
2020
International audience
Loss in microbial diversity affects nitrogen cycling in soil
2013
International audience; Microbial communities have a central role in ecosystem processes by driving the Earth's biogeochemical cycles. However, the importance of microbial diversity for ecosystem functioning is still debated. Here, we experimentally manipulated the soil microbial community using a dilution approach to analyze the functional consequences of diversity loss. A trait-centered approach was embraced using the denitrifiers as model guild due to their role in nitrogen cycling, a major ecosystem service. How various diversity metrics related to richness, eveness and phylogenetic diversity of the soil denitrifier community were affected by the removal experiment was assessed by 454 s…
Bridging microbial community ecology and nitrogen cycling in soil
2011
Pas de résumé
Ecophysiological analysis of the nitrophily of weed species
2013
International audience
Quantification of nitrogen fluxes and explanatory plant traits during a two year legume-cereal rotation
2018
National audience; A better understanding of how plant growth, N nutrition and symbiotic nitrogen fixation (SNF) are influenced by soil inorganic N availability, for a wide range of legume species, is crucial to optimise legume productivity, N2 fixation, while limiting environmental risks such as N leaching. A comparative analysis was performed for ten legume crops, grown in a field experiment and supplied with four levels of N fertiliser. Dry matter, N concentration and SNF were measured. Parallely, root traits were studied in a greenhouse experiment. For most species, inorganic N inputs had little effect on plant growth and N nutrition. SNF was negatively affected by soil inorganic N avai…
Pois protéagineux : cheminement de la recherche génétique pour la sélection des paramètres à prendre en compte pour l’amélioration de la stabilité du…
2013
Field Pea: development of genetic research for the selection of parameters to take into account to improve yield stability. Legumes were essential in rotations in the past, but they fell off during the 20th century. Maybe they will come back into favour in the 21st century thanks to its economy, agri-environment and food assets. Field Pea is the main crop of this family in France, but it remains underdeveloped because its unstable yield does not enable the farmers to ensure their income security. Therefore researchers should focus on yield stability. Modelling Pea remains difficult because of its indeterminate development. Parameters to take into account are many and their significance must…