Auteurs, date et publication :
Auteurs Genxing Pan , Zhiqun Huang , Jinkuan Wang , Hang Li , Abad Chabbi , Keith Paustian , Pete Smith
Date : 2025
Catégorie(s)
#ACBB #ACBB Lusignan #INRAEAuteurs, date et publication :
Auteurs Dan Binkley , Mark Adams , Todd Fredericksen , Jean Paul Laclau , Harri Mäkinen , Cindy Prescott
Publication : Forest Ecology and Management
Date : 2025
Volume : 410
Pages : 157-163
Catégorie(s)
#CIRAD #FORET Itatinga #INRAERésumé
Methods: Over 8 yr, we monitored vegetation changes in 24 experimental plots in two productive grasslands after modification of grazing intensity (including abandonment) or fertilization regime (including cessation of fertilization). Botanical surveys and plant trait measurements (LDMC, SLA and reproductive plant height) were performed within each plot. We analysed taxonomic responses using PRC and functional responses from observed temporal changes of CWM traits and Rao index.
Results: Grazing abandonment led to significant reductions in species richness and functional convergence toward taller plants with higher LDMC in both grasslands. Intermediate and high grazing pressure did not differ but showed strong variations in taxonomic diversity between years. Changes in functional vegetation structure were mostly driven by species turnover and weakly influenced by intraspecific trait variability. Community responses to modified fertilization regime were more complex, with strong differences between the two mown grasslands. Species richness did not change significantly although species evenness decreased in the highly fertilized treatments (NPK), particularly in the most productive grassland. Here, functional changes were largely driven by intraspecific trait variability. Both functional divergence and convergence were found for different traits. In NPK, grassland assemblages converged toward taller plants while SLA diverged.
Conclusions: In our upland study system the different components of grassland diversity responded differently, in terms of direction or rate of change and mostly under extreme modifications of management. Following abandonment, the observed patterns suggest a prominent and consistent role of competitive exclusion, as expected under the DEM. However, our findings also suggest the role of additional processes, especially the importance of niche differentiation, for our mown grassland under NPK. Timing and net effects of these combined assembly drivers were sensitive to even slight differences in initial productivity and species composition.
Auteurs, date et publication :
Auteurs Frédérique Louault , Julien Pottier , Priscilla Note , Denis Vile , Jean-François Soussana , Pascal Carrère , Hans Henrik Bruun
Publication : Journal of Vegetation Science
Date : 2025
Volume : 28
Issue : 3
Pages : 538-549
Catégorie(s)
#ACBB #ACBB Theix #INRAERésumé
The horse’s hindgut bacterial ecosystem has often been studied using faecal samples. However few studies compared both bacterial ecosystems and the validity of using faecal samples may be questionable. Hence, the present study aimed to compare the structure of the equine bacterial community in the hindgut (caecum, right ventral colon) and faeces using a fingerprint technique known as Automated Ribosomal Intergenic Spacer Analysis (ARISA). Two DNA extraction methods were also assessed. Intestinal contents and faeces were sampled 3 h after the morning meal on four adult fistulated horses fed meadow hay and pelleted concentrate. Irrespective of the intestinal segment, Principal Component Analysis of ARISA profiles showed a strong individual effect (P<0.0001). However, across the study, faecal bacterial community structure significantly (P<0.001) differed from those of the caecum and colon, while there was no difference between the two hindgut communities. The use of a QIAamp® DNA Stool Mini kit increased the quality of DNA extracted irrespective of sample type. The differences observed between faecal and hindgut bacterial communities challenge the use of faeces as a representative for hindgut activity. Further investigations are necessary to compare bacterial activity between the hindgut and faeces in order to understand the validity of using faecal samples.
Auteurs, date et publication :
Auteurs S. Sadet-Bourgeteau , C. Philippeau , S. Dequiedt , V. Julliand
Publication : animal
Date : 2014
Volume : 8
Issue : 12
Pages : 1928-1934
Catégorie(s)
#Genosol #INRAERésumé
In recent years, due to an increased need for non-intrusive sampling techniques, hydroacoustics has attracted attention in fishery science and management. Efforts to promote standardisation are increasing the accuracy, efficiency, and comparability of this method. The European Water Framework Directive and the Standard Operating Procedures for Fisheries Hydroacoustic Surveys in North American Great Lakes has recommended that surveys be conducted at night. At night, fish usually disperse in the water column, thus allowing for single echo detection and subsequent accurate fish size estimation, while day-time schooling behaviour hampers the estimation of fish size. However, sampling during the day would often be safer and cheaper. This study analyses how fisheries hydroacoustic results differ between day-time and night-time surveys, using data from 14 natural temperate lakes of various size. Data collected during the day and night at two depth layers linked to thermal stratification were compared in terms of acoustic scattering strength, target strength, and biomass estimates. The results showed a significant correlation between day-time and night-time estimates, though biomass in the upper layer was biased for day-time surveys, mainly due to incorrect fish size estimates resulting from rare single echo detections and schooling behaviour. Biomass estimates for the lower depth layer did not significantly differ between the two diel periods. Thus, this study confirms that hydroacoustic sampling in temperate lakes should be performed at night for accurate fish stock biomass estimates.
Auteurs, date et publication :
Auteurs Michaël Girard , Chloé Goulon , Anne Tessier , Pascal Vonlanthen , Jean Guillard
Publication : Aquatic Living Resources
Date : 2025
Volume : 33
Pages : 9
Catégorie(s)
#INRAE #OLARésumé
Sampling atmospheric particulate deposition (APD) in forest ecosystems highlights the need for methods to measure and analyze its organic and mineral repartition. We validated an organo-mineral repartition model of APD composition in open fields and below canopy with a mineral fraction, named mineral dust deposition (MDD), and particulate organic matter (POM). MDD is subdivided into soluble (S-MDD) and hardly soluble (H-MDD) fractions. To (i) monitor APD and its nutrient fluxes in forest ecosystems in the north of France and (ii) quantify the relative contribution of POM and MDD to APD, we adapted sampling materials and preparation methods that were developed for regions close to mineral dust sources. We have also compared two protocols. The ‘‘APD’’ protocol led to quick results for APD rates and POM contents. The ‘‘H-MDD’’ protocol is a treatment for soil samples that uses hydrogen peroxide, which solubilized both POM and S-MDD, and allowed detailed analyses of H-MDD. Both protocols induced a mass loss that was a maximum for the ‘‘H-MDD’’ protocol (31 ± 3%). The contribution of POM in APD in open fields (49 ± 10%) was lower than below the canopy (at least 66 ± 6%). H-MDD accounted for approximately 80% of the MDD mass and contained the largest portion of low-solubility elements (Si, Al and Fe). The fractions S-MDD and POM contained the largest portion of Ca and P (more than 70%). The two protocols were complementary and may be used successively to accurately describe APD.
Auteurs, date et publication :
Auteurs Émeline Lequy , Sébastien Conil , Marie-Pierre Turpault
Publication : Aeolian Research
Date : 2025
Pages : 9
Catégorie(s)
#FORET Breuil #FORET Montiers #INRAEAuteurs, date et publication :
Auteurs Daniel L. Yule , Lori M. Evrard , Sébastien Cachera , Michel Colon , Jean Guillard
Publication : Freshwater Biology
Date : 2025
Volume : 58
Issue : 10
Pages : 2074-2088
Catégorie(s)
#INRAE #OLARésumé
In search of a primer set that could be used to study Planctomycetes dynamics in lakes and especially via fingerprinting methods, e.g. denaturing gradient gel electrophoresis (DGGE), three existing specific primer sets, developed for marine and soil systems, have been tested on water samples from four freshwater ecosystems. The first primer set (PLA46F/ PLA886R) allowed PCR amplification of Planctomycetes sequences in only one of the four ecosystems, whereas the second primer set (PLA40F/ P518R) amplified Planctomycetes sequences in all the studied ecosystems but with a low specificity, since sequences belonging to Verrucomicrobiales and Chlamydiales clades were also amplified. Finally, the third primer set (PLA352F/PLA920R) allowed amplification of Planctomycetes sequences in the four ecosystems with a very high specificity. It amplified all known Planctomycetes genera and yielded the highest Operational Taxonomic Unit (OTU) richness and diversity estimates. In silico analyses supported these results. Further experiments comparing PLA352F/PLA920R to PLA46F/P1390R (a primer set generating a longer PCR fragment, also used to study Planctomycetes) yielded very similar results. Our findings suggest that the primer set PLA352F/ PLA920R provides good estimates of Planctomycetes richness and diversity compared with other, and can thus be used to study Planctomycetes dynamics in lentic freshwater ecosystems.
Auteurs, date et publication :
Auteurs Thomas Pollet , Rémy D. Tadonléké , Jean-F. Humbert
Publication : Environmental Microbiology Reports
Date : 2025
Volume : 3
Issue : 2
Pages : 254-261
Catégorie(s)
#INRAE #OLAAuteurs, date et publication :
Auteurs L. Pourcelot , Ph Calmon , F. Chabaux , S. Conil , C. Galy , M. Granet , E. Lascar , E. Leclerc , T. Perrone , P.O. Redon , S. Rihs
Publication : Applied Geochemistry
Date : 2025
Volume : 84
Pages : 314-324
Catégorie(s)
#FORET Montiers #INRAEAuteurs, date et publication :
Auteurs Lais Gonzaga Gomez , Benjamin Loubet , Florence Lafouge , Raluca Ciuraru , Pauline Buysse , Brigitte Durand , Jean-Christophe Gueudet , Olivier Fanucci , Alain Fortineau , Olivier Zurfluh , Céline Decuq , Julien Kammer , Pascal Duprix , Sandy Bsaibes , François Truong , Valérie Gros , Christophe Boissard
Publication : Atmospheric Environment
Date : 2025
Volume : 214
Pages : 116855