Search results for "cycle"

Spécificité des besoins de recherche sur la qualité des sols en Agriculture Biologique. Bilan d’un séminaire transdisciplinaire INRA-ITAB

2023

In November 2018, ITAB (Institute of Agriculture and Organic Food) and INRA (National Institute for Agronomic Research) organized a transdisciplinary seminar to bring together stakeholders to: i) share issues associated with soil management in Organic Farming (OF) systems, ii) collectively define the main research questions to be addressed; and iii) facilitate the construction of networks or projects. More than 150 participants attended the seminar, which was designed using the method of citizen facilitation of the community forum type (Town Hall Meeting) allowing all parties to express themselves and a live summary by experts. The seminar identified important knowledge gaps on soils in OF …

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…

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…

Impact d'un déficit hydrique sur Pisum sativum cv. Kayanne cultivé dans du sol en RhizoTubes

2018

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

Global equatorial variability of 850 and 200 hPa zonal winds from rawinsondes between 1963 and 1989

1995

The longitude-height-time variability of 3-month averaged zonal wind anomalies at 850 and 200 hPa over the equatorial area (5{degrees}N-5{degrees}S) is analyzed using a three-dimensional dataset constructed from rawinsonde data (1963-1989). The first mode, closely related to the Southern Oscillation Index, suggests a strong vertical coupling associated with a horizontal out-of-phase pattern between the central/western Pacific and the remainder of the equatorial belt. The vertical coupling appears to be phase-locked to the annual cycle with strongest intensities found over South America and near the maritime continent early in the calendar year and over the Pacific basin and Africa during th…

Modalités fonctionnelles et évolutives des parasitoses développées par les crabes Pinnotheridae aux dépens des échinides fouisseurs

2010

Ce travail s’est intéressé aux liens existant entre la stratégie d’exploitation développée par un crustacé ectoparasite et son comportement reproductif. Le crabe Pinnotheridae Dissodactylusprimitivus exploite deux espèces Spatangidae vivant dans la Mer des Caraïbes, Meomaventricosa et Plagiobrissus grandis. Des approches comportementales, démographiques etgénétiques ont été adoptées afin de mettre en lumière le fonctionnement et la biologie de cettesymbiose. Par son comportement alimentaire, le crabe occasionne des lésions tégumentairessur ses hôtes. Celles-ci affectent la fitness de M. ventricosa, au travers de son développementgonadique. Dissodactylus primitivus exploite ses deux espèces …

Typology of exogenous organic matters based on chemical and biochemical composition to predict potential nitrogen mineralization

2010

Our aim was to develop a typology predicting potential N availability of exogenous organic matters (EOMs) in soil based on their chemical characteristics. A database of 273 EOMs was constructed including analytical data of biochemical fractionation, organic C and N, and results of N mineralization during incubation of soil–EOM mixtures in controlled conditions. Multiple factor analysis and hierarchical classification were performed to gather EOMs with similar composition and N mineralization behavior. A typology was then defined using composition criteria to predict potential N mineralization. Six classes of EOM potential N mineralization in soil were defined, from high potential N minerali…

Le Priming Effect dans le sol : mécanismes, acteurs et conséquences sur les services écosystémiques dans un contexte de changement global

2022

The priming effect (PE) is a key mechanism contributing to the carbon balance of the soil ecosystem. Almost 100 years of research since its discovery in 1926 have led to a rich body of scientific publications to identify the drivers and mechanisms involved. A few review articles have summarised the acquired knowledge; the last major one was published in 2010. Since then, knowledge on the soil microbial communities involved in PE and in PE + C sequestration mechanisms has been considerably renewed.This article reviews current knowledge on soil PE to state to what extent new insights may improve our ability to understand and predict the evolution of soil C stocks. We propose a framework to un…