Résumé
A basic understanding of nutrition effects on the mechanisms involved in tree response to drought is essential under a future drier climate. A large-scale throughfall exclusion experiment was set up in Brazil to gain an insight into the effects of potassium (K) and sodium (Na) nutrition on tree structural and physiological adjustments to water deficit. Regardless of the water supply, K and Na supply greatly increased growth and leaf area index (LAI) of Eucalyptus grandis trees over the first 3yr after planting. Excluding 37% of throughfall reduced above-ground biomass accumulation in the third year after planting for K- supplied trees only. E.grandis trees were scarcely sensitive to drought as a result of the utilization of water stored in deep soil layers after clear-cutting the previous plantation. Trees coped with water restriction through stomatal closure (isohydrodynamic behavior), osmotic adjustment and decrease in LAI. Additionally, droughted trees showed higher phloem sap sugar concentrations. K and Na supply increased maximum stomatal conductance, and the high water requirements of fertilized trees increased water stress during dry periods. Fertilization regimes should be revisited in a future drier climate in order to find the right balance between improving tree growth and limiting water shortage.
Auteurs, date et publication :
Auteurs P. Battie-Laclau , J.-P. Laclau , J.-C. Domec , M. Christina , J.-P. Bouillet , M.-C. Piccolo , J.-L. de Moraes Goncalves , R. Moreira e Moreira , A.-V. Krusche , J.-M. Bouvet , Y. Nouvellon
Publication : New Phytologist
Date : 2014
Volume : 203
Issue : 2
Pages : 401-413
Catégorie(s)
#CIRAD #FORET Itatinga #INRAEAuteurs, date et publication :
Auteurs Benjamin Alric , Marie-Elodie Perga
Publication : Hydrobiologia
Date : 2025
Volume : 676
Issue : 1
Pages : 101-116
Catégorie(s)
#INRAE #OLAAuteurs, date et publication :
Auteurs Thierry Caquet , Marc Roucaute , Pierre Le Goff , Laurent Lagadic
Publication : Ecotoxicology and Environmental Safety
Date : 2011
Volume : 74
Issue : 5
Pages : 1122-1130
Catégorie(s)
#INRAE #PEARLRésumé
Soil-crop models are used to simulate ecological processes from the field to the regional scale. Main inputs are soil and
climate data in order to simulate model response variables such as crop yield. We investigate the effect of changing the
resolution of input data on simulated crop yields at a regional scale using up to ten dynamic crop models. For these
models we compared the effects of spatial input data aggregation for wheat and maize yield of two regions with
contrasting climate conditions (1) Tuscany (Italy, Mediterranean climate) and (2) North Rhine Westphalia (NRW,
Germany, temperate climate). Soil and climate data of 1 km resolution were aggregated to resolutions of 10, 25, 50, and
100 km by selecting the dominant soil class (and corresponding soil properties) and by arithmetic averaging, respectively.
Differences in yield simulated at coarser resolutions from the yields simulated at 1 km resolution were calculated
to quantify the effect of the aggregation of the input data (soil and climate data) on simulation results.
The mean yield difference (bias) at the regional level was positive due to the upscaling of productive
dominant soil(s) to coarser resolution. In both regions and for both crops, aggregation effects (i.e. errors in
simulation of crop yields at coarser spatial resolution) due to the combined aggregation of soil and climate input
data increased with decreasing resolution, whereby the aggregation error for Tuscany was larger than for North
Rhine Westphalia (NRW). The average absolute percentage yield differences between grid cell yields at the
coarsest resolution (100 km) compared to the finest resolution (1 km) were by about 20–30% for Tuscany and
less than 15 and 20% for NRW for winter wheat and silage maize, respectively.
In the Mediterranean area, the prediction errors of the simulated yields could reach up to 60% when looking
at individual crop model simulations. Additionally, aggregating soil data caused larger aggregation errors in
both regions than aggregating climate data.
Those results suggest that a higher spatial resolution of climate and especially of soil input data are necessary
in Mediterranean areas than in temperate humid regions of central Europe in order to predict reliable regional
yield estimations with crop models. For generalization of these outcomes, further investigations in other subhumid
or semi-arid regions will be necessary.
Auteurs, date et publication :
Auteurs Ganga Maharjan , Holger Hoffmann , Heidi Webber , Amit Srivastava , Lutz Weihermüller , A. Villa Solis , Elsa Coucheney , Elisabet Lewan , Giacomo Trombi , Marco Moriondo , Marco Bindi , Balazs Grosz , Rene Dechow , Matthias Kuhnert , Luca Doro , Kurt Kersebaum , Tommaso Stella , Xenia Specka , Claas Nendel , Thomas Gaiser
Publication : European Journal of Agronomy
Date : 2019
Volume : 103
Pages : 32-46
Catégorie(s)
#INRAE #RecordAuteurs, date et publication :
Auteurs Lydie Blottière , Mourad Jaffar-Bandjee , Stéphan Jacquet , Alexis Millot , Florence D. Hulot
Publication : Freshwater Biology
Date : 2025
Volume : 62
Issue : 1
Pages : 161-177
Catégorie(s)
#CNRS #ENS #INRAE #OLAAuteurs, date et publication :
Auteurs Olga Savichtcheva , Didier Debroas , Marie Elodie Perga , Fabien Arnaud , Clément Villar , Emilie Lyautey , Amy Kirkham , Cécile Chardon , Benjamin Alric , Isabelle Domaizon
Publication : Freshwater Biology
Date : 2025
Volume : 60
Issue : 1
Pages : 31-49
Catégorie(s)
#INRAE #OLARésumé
Soil compaction decreases soil aeration and water infiltration, lowering air-filled porosity, which may impact biological processes involved in soil fluxes of carbon dioxide (F-co2) and methane (F-cH4), and decrease the greenhouse gas emissions mitigation potential offered by the forestry sector. We recorded F-co2 and F-cH4 continuously for two years using automated chambers connected to a laser-based gas analyser in an experimental forest site on an acidic ruptic Luvisol that was established to assess the long-term impact of a loaded forwarder. Heavy machine traffic had considerably increased soil surface roughness. Air-filled porosity (AFP) in the first 0.1 m was lower in the trafficked plot especially in hollows than in the control almost all year long. The temperature sensitivity of F-co2 was higher for the control plot than for both mounds and hollows in the trafficked plot. Cumulative F-co2 was much higher in the control than in hollows and mounds of the trafficked plot. In contrast, annual F-cH4 did not significantly differ between the control plot and either the mounds or the hollows in the trafficked plot, but was significantly higher in mounds than in hollows. F-cH4 was negative all year round indicating a net uptake of CH4, except during winter when a net emission of CH4 was occasionally observed in the hollows on the trafficked plot. While seasonal variations of F-cH4 were well related to variations in AFP, the potential rate of methane uptake at optimal air-filled porosity was higher in the trafficked plot than in the control. (C) 2016 Elsevier B.V. All rights reserved.
Auteurs, date et publication :
Auteurs Daniel Epron , Caroline Plain , Fatou-Kine Ndiaye , Pascal Bonnaud , Catherine Pasquier , Jacques Ranger
Publication : Forest Ecology and Management
Date : 2016
Volume : 382
Pages : 1-9
Catégorie(s)
#FORET Azerailles-Clermont #FORET Itatinga #INRAEAuteurs, date et publication :
Auteurs Muhammad Sanaullah , Abad Chabbi , Cyril Girardin , Jean-Louis Durand , Magalie Poirier , Cornelia Rumpel
Publication : Plant and soil
Date : 2025
Volume : 374
Issue : 1-2
Pages : 767–778
Catégorie(s)
#ACBB #ACBB Lusignan #INRAERésumé
Background and Aims Legume use in forage production may replace mineral fertiliser N input by biological nitrogen fixation in grass-legume mixtures. However, these systems may also have high phosphorus requirements. The aim of the study was to determine the amount and composition of C, N and P forms in grassland soil under two different graminaceous species grown in monoculture or in mixture with a legume.
Auteurs, date et publication :
Auteurs Alexandra Crème , Cornelia Rumpel , François Gastal , Maria de la Luz Mora Gil , Abad Chabbi
Publication : Plant and Soil
Date : 2025
Volume : 402
Issue : 1-2
Pages : 117-128
Catégorie(s)
#ACBB #ACBB Lusignan #INRAEAuteurs, date et publication :
Auteurs Naoise Nunan , Julie Leloup , Léo S. Ruamps , Valérie Pouteau , Claire Chenu
Publication : Scientific Reports
Date : 2025
Volume : 7
Issue : 1