Auteurs, date et publication :
Auteurs Falkowski M , M. Coke , et al
Date : 2025
Catégorie(s)
#INRAE #PEARLRésumé
Soil DNA extraction has become a critical step in describing microbial biodiversity. Historically, ascertaining overarching microbial ecological theories has been hindered as independent studies have used numerous custom and commercial DNA extraction procedures. For that reason, a standardized soil DNA extraction method (ISO-11063) was previously published. However, although this ISO method is suited for molecular tools such as quantitative PCR and community fingerprinting techniques, it has only been optimized for examining soil bacteria. Therefore, the aim of this study was to assess an appropriate soil DNA extraction procedure for examining bacterial, archaeal and fungal diversity in soils of contrasting land-use and physico-chemical properties. Three different procedures were tested: the ISO-11063 standard; a custom procedure (GnS-GII); and a modified ISO procedure (ISOm) which includes a different mechanical lysis step (a FastPrep ®-24 lysis step instead of the recommended bead-beating). The efficacy of each method was first assessed by estimating microbial biomass through total DNA quantification. Then, the abundances and community structure of bacteria, archaea and fungi were determined using real-time PCR and terminal restriction fragment length polymorphism approaches. Results showed that DNA yield was improved with the GnS-GII and ISOm procedures, and fungal community patterns were found to be strongly dependent on the extraction method. The main methodological factor responsible for differences between extraction procedure efficiencies was found to be the soil homogenization step. For integrative studies which aim to examine bacteria, archaea and fungi simultaneously, the ISOm procedure results in higher DNA recovery and better represents microbial communities.
Auteurs, date et publication :
Auteurs Pierre Plassart , Sébastien Terrat , Bruce Thomson , Robert Griffiths , Samuel Dequiedt , Mélanie Lelievre , Tiffanie Regnier , Virginie Nowak , Mark Bailey , Philippe Lemanceau , Antonio Bispo , Abad Chabbi , Pierre-Alain Maron , Christophe Mougel , Lionel Ranjard
Publication : Plos One
Date : 2012
Volume : 7
Issue : 9
Pages : e44279
Catégorie(s)
#ACBB #ACBB Lusignan #Genosol #INRAEAuteurs, date et publication :
Auteurs Arnaud Auber
Date : 2025
Catégorie(s)
#INRAE #PEARLAuteurs, date et publication :
Auteurs J. Devillers , F. Darriet , C. Delorme , X. Deparis , J-P. Jaeg , Laurent Lagadic , Christophe Lagneau , B. Lapied , F. Quiniou , O. Yamada , A. Yebakima
Date : 2012
Catégorie(s)
#INRAE #PEARLAuteurs, date et publication :
Auteurs N. Baghdadi , G. le Maire , J. Bailly , K. Ose , Y. Nouvellon , M. Zribi , C. Lemos , R. Hakamada
Publication : IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Date : 2025
Volume : 99
Pages : 1610
Catégorie(s)
#CIRAD #FORET Itatinga #INRAERésumé
Field scale flux measurements of volatile organic compounds (VOC) are
essential for improving our knowledge of VOC emissions from ecosystems.
Many VOCs are emitted from and deposited to ecosystems. Especially less
known, are crops which represent more than 50% of French terrestrial
surfaces. In this study, we evaluate a new on-line methodology for
measuring VOC fluxes by Eddy Covariance with a PTR-Qi-TOF-MS.
Measurements were performed at the ICOS FR-GRI site over a crop using a
30 m long high flow rate sampling line and an ultrasonic anemometer. A
Labview program was specially designed for acquisition and on-line
covariance calculation: Whole mass spectra ( 240000 channels) were
acquired on-line at 10 Hz and stored in a temporary memory. Every 5
minutes, the spectra were mass-calibrated and normalized by the primary
ion peak integral at 10 Hz. The mass spectra peaks were then retrieved
from the 5-min averaged spectra by withdrawing the baseline, determining
the resolution and using a multiple-peak detection algorithm. In order
to optimize the peak detection algorithm for the covariance, we
determined the covariances as the integrals of the peaks of the
vertical-air-velocity-fluctuation weighed-averaged-spectra. In other
terms, we calculate , were w is the vertical
component of the air velocity, Sp is the spectra, t is time, lag is the
decorrelation lag time and denotes an average. The lag time
was determined as the decorrelation time between w and the primary ion
(at mass 21.022) which integrates the contribution of all reactions of
VOC and water with the primary ion. Our algorithm was evaluated by
comparing the exchange velocity of water vapor measured by an open path
absorption spectroscopy instrument and the water cluster measured with
the PTRQi-TOF-MS. The influence of the algorithm parameters and lag
determination is discussed. This study was supported by the ADEME-CORTEA
COV3ER project (http://www6.inra.fr/cov3er).
Auteurs, date et publication :
Auteurs Benjamin Loubet , Pauline Buysse , Florence Lafouge , Raluca Ciuraru , Céline Decuq , Olivier Zurfluh
Date : 2017
Volume : 19
Pages : 16989
Catégorie(s)
#INRAE #PT-RMSAuteurs, date et publication :
Auteurs Beillard A.
Date : 2025
Catégorie(s)
#INRAE #PEARLRésumé
The association of N-2-fixing species (NFS) could be an attractive option for achieving a sustainable increase of Eucalyptus plantations (EP) productivity through a positive balance between facilitative effects and competition between species. A randomised block design was replicated at four sites (Cenibra, USP, Suzano and IP) in Southern Brazil and at one site in Congo. The development of mono-specific stands of Acacia mangium (100A) and Eucalyptus grandis or urophylla x grandis (100E), was compared with N fertilisation treatment (100E + N) and with mixed-species plantations in a 1:1 ratio (50A:50E), and in an additive series with varying densities of acacia for the same density of eucalypt (25A:100E, 50A:100E, 100A:100E). The objectives were to assess the effect of mixtures on tree growth and stand production, and the behaviour of the two species in contrasting soil and climatic conditions. Tree growth was monitored over stand rotation and the biomass of aboveground tree components estimated at mid-rotation and at harvesting age. Eucalyptus height was 13% higher in Brazil than in Congo. Favourable ecological conditions in Congo and Cenibra led to 50% higher Acacia tree height than at the other sites. A depressive effect of Eucalyptus neighbour trees on Acacia height and circumference growth, lower in Congo than in Brazil, was observed in the mixtures from age 1-2 years onwards. Depressive effects of acacia on eucalypt height and circumference growth were low in USP, Suzano and IP, high in Cenibra, and not observed in Congo, in 50A:50E and 25A:100E. A positive though insignificant response to N fertilisation was only found in USP and Congo. Complementarity for light and soil resource capture between Eucalyptus and Acacia trees resulted in mean annual increments in total stand stemwood biomass (MAI) that were 7-15%, 6-12%, and 40% higher in the additive series than for 100E in Cenibra, LISP and Congo, respectively at mid-rotation. Whilst lasting complementarity and facilitation in Congo led to 17-34% higher MAI in mixtures than for 100E at harvesting age, MAIs were not significantly higher in mixtures than for 100E in Brazil. Mixed-species plantations of Eucalyptus and A. mangium might enhance aboveground stand production on poor nutrient soils in warm and humid tropical climates with low water limitations. (c) 2012 Elsevier B.V. All rights reserved.
Auteurs, date et publication :
Auteurs J.-P. Bouillet , J.-P. Laclau , J.-L. de Moraes Goncalves , M. Voigtlaender , J.-L. Gava , F.-P. Leite , R. Hakamada , L. Mareschal , A. Mabiala , F. Tardy , J. Levillain , P. Deleporte , D. Epron , Y. Nouvellon
Publication : Forest Ecology and Management
Date : 2013
Volume : 301
Pages : 89-101
Catégorie(s)
#CIRAD #FORET Itatinga #INRAEAuteurs, date et publication :
Auteurs Bini D , Alcantara dos Santos C , Bouillet J P , De Morais Gonçalves J L , Bran Nogueira Cardoso E J
Publication : Applied soil ecology
Date : 2025
Volume : 63
Pages : 57-66
Catégorie(s)
#CIRAD #FORET Itatinga #INRAERésumé
Dès son introduction à Madagascar, Eucalyptus robusta a été retenu comme espèce de reboisement pour sa remarquable capacité d'adaptation. L'extension de sa plantation par les populations rurales a abouti à la création d'un massif de près de 140 000 hectares autour d'Antananarivo. Son bois est devenu la principale source d'énergie utilisée par les ménages urbains et ruraux malgaches. Mais aujourd'hui, la production durable de cette ressource est gravement menacée. Le marché déficitaire et la pauvreté des populations rurales amènent les propriétaires forestiers à exploiter leurs taillis avec des rotations de plus en plus courtes, parfois inférieures à 2 ans. Cette surexploitation induit un gaspillage des éléments minéraux qui ne sont pas compensés par des apports extérieurs de nutriments. La production de charbon de bois se poursuit à partir de meules traditionnelles dont le rendement pondéral n'est que de 10 % environ. Le doublement de ce rendement par des méthodes simples permettrait pourtant de diminuer les superficies de forêt exploitées chaque année. À 6 ans, l'accroissement moyen annuel en volume commercial bois fort sur écorce des taillis anciens est de 18,8 m 3 /ha/an. Les meilleures provenances importées récemment permettent de doubler le volume moyen individuel des arbres à 9 ans. Des vergers à graines ont été plantés avec plusieurs provenances de l'aire naturelle pour créer des variétés composites. Cependant, des fécondations préférentielles intra-provenances et des pollutions par le pollen extérieur affectent fortement la qualité des variétés produites. Pour l'extension du massif d'eucalyptus, les populations rurales continuent à utiliser des graines locales ou planter des sauvageons. Ces plantations en E. robusta devront continuer à produire du bois malgré les modifications biotiques et abiotiques déjà constatés à Madagascar. Face à ces changements, les technologies modernes peuvent aider la recherche forestière à proposer un système durable de production de bois énergie autour des grands centres urbains. Cela aurait pour effet de maintenir un revenu régulier participant à la survie des populations rurales. (Résumé d'auteur)
Auteurs, date et publication :
Auteurs D. Verhaegen , H. Randrianjafy , H. Rakotondraoelina , M.-C. Trendelenburg Rakotonirina , N. Andriamampianina , P. Montagne , A. Rasamindisa , G. Chaix , J.-P. Bouillet , J.-M. Bouvet
Publication : Bois et Forêts des Tropiques
Date : 2025
Issue : 320
Pages : 15-30