Résumé
Better knowledge and a more complete long-term monitoring of tree species phenology and tree foliage development are crucial to accurately estimating the impact of climate change on forest ecosystems functioning and on forest species distribution. We set up global solar radiation sensors under the forest canopy and continuously recorded solar radiation in order to follow the development of sessile oak (Quercus petraea L.) foliage in pure stands over four consecutive years and for two levels of stand density. At the same time, we made phenological observations to determine bud burst date. One of our goals was to link observed bud burst dates and transmittance measurements. Our results show that solar radiation transmittance during the leaf unfolding period followed a sigmoid-shaped curve; and that it was possible to fit a generalized logistic model to determine a set of parameters characterizing tree foliage and its development during the unfolding period. Among these parameters, we suggest that the date at which solar radiation interception by foliage reaches 50% could be used to monitor the beginning of the growing season over the long term. The relationship between observed bud burst date and the transmittance model parameters was more complex than we expected. We tested several indices to deduce the date of bud burst from transmittance. We showed that when radiation interception due to foliage reached 10%, this indicated the observed bud burst date. Finally, a linear model including parameters from the generalized logistic models of transmittance as predictors explained 57% of the variability in bud burst date. Complementary research combining light measurements and phenological observations over a longer period of time is needed to know whether these relationships could help estimate bud burst date regardless of the year or the stand density.
Auteurs, date et publication :
Auteurs Thomas Perot , Philippe Balandier , Camille Couteau , Sandrine Perret , Vincent Seigner , Nathalie Korboulewsky
Publication : AGRICULTURAL AND FOREST METEOROLOGY
Date : 2019
Volume : 275
Pages : 37-46
Catégorie(s)
#ANR-Citation #FORET OPTMix #INRAERésumé
Natural products have proven to be an immeasurable source of bioactive compounds. The exceptional biodiversity encountered in Amazonia, alongside a rich entomofauna and frequent interactions with various herbivores is the crucible of a promising chemodiversity. This prompted us to search for novel botanical insecticides in French Guiana. As this French overseas department faces severe issues linked to insects, notably the strong incidence of vector-borne infectious diseases, we decided to focus our research on products able to control the mosquito Aedes aegypti. We tested 452 extracts obtained from 85 species originating from 36 botanical families and collected in contrasted environments against an Ae. aegypti laboratory strain susceptible to all insecticides, and a natural population resistant to both pyrethroid and organophosphate insecticides collected in Cayenne for the most active of them. Eight species (Maytenus oblongata Reissek, Celastraceae; Costus erythrothyrsus Loes., Costaceae; Humiria balsamifera Aubl., Humiriaceae; Sextonia rubra (Mez) van der Werff, Lauraceae; Piper hispidum Sw., Piperaceae; Laetia procera (Poepp.) Eichl., Salicaceae; Matayba arborescens (Aubl.) Radlk., Sapindaceae; and Cupania scrobitulata Rich., Sapindaceae) led to extracts exhibiting more than 50% larval mortality after 48 h of exposition at 100 µg/mL against the natural population and were considered active. Selectivity and phytochemistry of these extracts were therefore investigated and discussed, and some active compounds highlighted. Multivariate analysis highlighted that solvents, plant tissues, plant family and location had a significant effect on mortality while light, available resources and vegetation type did not. Through this case study we highlighted that plant defensive chemistry mechanisms are crucial while searching for novel insecticidal products.
Auteurs, date et publication :
Auteurs Michaël Falkowski , Arnaud Jahn-Oyac , Guillaume Odonne , Claudiane Flora , Yannick Estevez , Seindé Touré , Isabelle Boulogne , Jean-Charles Robinson , Didier Béreau , Philippe Petit , Didier Azam , Maïra Coke , Jean Issaly , Pascal Gaborit , Didier Stien , Véronique Eparvier , Isabelle Dusfour , Emeline Houël
Publication : Acta Tropica
Date : 2025
Volume : 201
Pages : 105179
Catégorie(s)
#ANR-Citation #INRAE #PEARLRésumé
Aim Intensive studies since the beginning of the 21st century have provided vast amounts of knowledge about soil microbial diversity at local and global scales. However, microbial habitats have been poorly investigated at large scale. This study aims to characterize soil bacterial habitats across France for the first time by integrating the description of numerous environmental factors and human activities. Location We focus on the large spatial scale of mainland France using the largest spatially explicit soil sampling set available across France (2,173 soils, area = 5.5 × 105 km2). Major taxa studied Soil bacteria and archaea were studied by a high throughput sequencing approach targeting the V3-V4 region of the 16S ribosomal ribonucleic acid (rRNA) gene directly amplified from soil DNA. Methods We applied decision tree learning and geostatistical approaches combining the abundant data on soil microbes and large-scale environmental description in order to conduct a comprehensive analysis of soil bacterial and archaeal communities. Results We identified a complex mosaic of 16 distinct terrestrial habitats, based on soil type and management (pH, C : N ratio, land use). As for plants and animals, each habitat hosted generalist and specialist taxa and a specific interaction network directly or indirectly impacted by human activities. Main conclusions In a context of global change, our results emphasize that the policies for biodiversity and habitat conservation should now integrate soil microorganisms conceptually and technically.
Auteurs, date et publication :
Auteurs Battle Karimi , Jean Villerd , Samuel Dequiedt , Sébastien Terrat , Nicolas Chemidlin-Prévost Bouré , Christophe Djemiel , Mélanie Lelièvre , Julie Tripied , Virginie Nowak , Nicolas P. A. Saby , Antonio Bispo , Claudy Jolivet , Dominique Arrouays , Patrick Wincker , Corinne Cruaud , Lionel Ranjard
Publication : Global Ecology and Biogeography
Date : 2025
Volume : 29
Issue : 8
Pages : 1399-1411
Catégorie(s)
#ANR-Citation #Genosol #INRAERésumé
Production of biogas through anaerobic digestion of organic wastes should play an important role in sustainable development of energy supply, and the environmental effects of digestates have to be assessed. We investigated the effect of anaerobic digestion of pig slurry (PS) on the molecular quality of the digestate produced. The consequences of digested (DPS) and undigested PS use as organic soil fertilizer on soil microbial and biochemical properties and C-gas emissions (CO2 and volatile organic compounds) were studied during a two-month incubation. PS and DPS differed in the amount of volatile organic compounds (VOCs) emitted, in their organic C and lignin contents but not in their active microbial composition. Application of both types of slurry to the soil immediately increased the content of soil dissolved organic carbon (DOC) compared to the control soil. The application of DPS induced few changes in the biochemical composition of soil organic matter compared to its raw material (PS) that increased the amount of phenolic compounds. After 60 days, both amended and control soils contained similar amounts of DOC, amended soils presenting a more diverse biochemical composition of their soil organic matter. Application of both slurries to soil triggered a succession of different active microbial communities, which could be attributed to the introduction of new microorganisms and the input of new labile organic carbon. Changes in fungal communities were stronger than those of bacteria and archaea; however, only slight differences were observed between the slurries. Different fluxes and emission dynamics of five VOCs (methanol, acetone, DMS, 2-pentanone and phenol) were observed during the incubation time following application of PS or DPS to soil while no differences in CO2 emissions were observed. The present study calls for long-term field studies with VOC analyses as a promising tool to differentiate organic fertilization practices.
Auteurs, date et publication :
Auteurs Cécile Monard , Laurent Jeanneau , Jean-Luc Le Garrec , Nathalie Le Bris , Françoise Binet
Publication : Applied Soil Ecology
Date : 2025
Volume : 147
Pages : 103376
Catégorie(s)
#ANR-Citation #INRAE #PRO #PRO EFELEAuteurs, date et publication :
Auteurs Amandine Laffite , Alessandro Florio , Kasaina Sitraka Andrianarisoa , Charline Creuze des Chatelliers , Brigitte Schloter‐Hai , Sidy M. Ndaw , Charlotte Periot , Michael Schloter , Bernd Zeller , Franck Poly , Xavier Le Roux
Publication : Environmental Microbiology
Date : 2025
Volume : 22
Issue : 3
Pages : 1141-1153
Catégorie(s)
#FORET Breuil #INRAEAuteurs, date et publication :
Auteurs Gabriel Y.K. Moinet , Matthias Moinet , John E. Hunt , Cornelia Rumpel , Abad Chabbi , Peter Millard
Publication : Science of The Total Environment
Date : 2025
Volume : 704
Pages : 135460
Catégorie(s)
#ACBB #ACBB Lusignan #INRAEAuteurs, date et publication :
Auteurs Tanya L. Rogers , Stephan B. Munch , Simon D. Stewart , Eric P. Palkovacs , Alfredo Giron‐Nava , Shin‐ichiro S. Matsuzaki , Celia C. Symons , Tim Coulson
Publication : Ecology Letters
Date : 2025
Volume : 23
Issue : 8
Pages : 1287-1297
Catégorie(s)
#INRAE #OLAAuteurs, date et publication :
Auteurs Jean-Philippe Jenny , Orlane Anneville , Fabien Arnaud , Yoann Baulaz , Damien Bouffard , Isabelle Domaizon , Serghei A. Bocaniov , Nathalie Chèvre , Maria Dittrich , Jean-Marcel Dorioz , Erin S. Dunlop , Gaël Dur , Jean Guillard , Thibault Guinaldo , Stéphan Jacquet , Aurélien Jamoneau , Zobia Jawed , Erik Jeppesen , Gail Krantzberg , John Lenters
Publication : Journal of Great Lakes Research
Date : 2025
Volume : 46
Issue : 4
Pages : 686-702
Catégorie(s)
#INRAE #OLAAuteurs, date et publication :
Auteurs Florent Levavasseur , Bruno Mary , Bent T. Christensen , Annie Duparque , Fabien Ferchaud , Thomas Kätterer , Hélène Lagrange , Denis Montenach , Camille Resseguier , Sabine Houot
Publication : Nutrient Cycling in Agroecosystems
Date : 2025
Volume : 117
Issue : 2
Pages : 215-229
Catégorie(s)
#INRAE #PRO #PRO QualiAgroRésumé
Tree species mixing has been widely promoted as a promising silvicultural tool for reducing drought stress. However, so far only a limited number of species combinations have been studied in detail, revealing inconsistent results. In this study, we analysed the effect of mixing Scots pine and oak (pedunculate oak and sessile oak) trees on their drought response along a comprehensive ecological gradient across Europe. The objective was to improve our knowledge of general drought response patterns of two fundamental European tree species in mixed versus monospecific stands. We focused on three null hypotheses: (HI ) tree drought response does not differ between Scots pine and oak, (HII ) tree drought response of Scots pine and oak is not affected by stand composition (mixture versus monoculture) and (HIII ) tree drought response of Scots pine and oak in mixtures and monocultures is not modified by tree size or site conditions. To test the hypotheses, we analysed increment cores of Scots pine and oak, sampled in mixed and monospecific stands, covering a wide range of site conditions.
Auteurs, date et publication :
Auteurs M. Steckel , M. del Río , M. Heym , J. Aldea , K. Bielak , G. Brazaitis , J. Černý , L. Coll , C. Collet , M. Ehbrecht , A. Jansons , A. Nothdurft , M. Pach , M. Pardos , Q. Ponette , D.O.J. Reventlow , R. Sitko , M. Svoboda , P. Vallet , B. Wolff
Publication : Forest Ecology and Management
Date : 2025
Volume : 461