2022 - UMR Silva

[hal-05240498] Quantitative expression of mesophyll conductance temperature response in the FvCB model and impacts on plant gas exchange estimations

<div><p>The way of quantitatively expressing mesophyll conductance (g m ) in the Farquhar-von Caemmerer-Berry (FvCB) photosynthesis model and its impacts on plant gas exchange estimations have not been well explored, primarily due to huge uncertainties in g m parameterization. Here, a peaked Arrhenius function to depict g m temperature response was introduced into the FvCB model and parameterized through evaluating four different g m estimation methods in 19 C 3 species at 31 experimental treatments. Results indicated that the FvCB model without explicitly considering g m cannot perform well in eight species/treatments, while the model that considers g m estimated by the chlorophyll fluorescence-gas exchange method and biochemical parameters estimated by the Bayesian retrieval algorithm was superior. Overall modeling accuracy was not further ameliorated when taking anatomybased g m into consideration. The increasing Arrhenius function without considering the suboptimal stage of g m temperature response caused significant overestimations in photosynthesis under high leaf temperatures by 2-3 folds. The g m explicit expression had equally important effects on photosynthesis and transpiration estimations, which disagreed with "the asymmetric effects on photosynthesis and transpiration estimations" hypothesis proposed by Knauer et al. (2020). Literature survey plus our data indicated that observed variations of photosynthesis optimal temperature (T optA ) were primarily explained by the g m optimal temperature (T opt _g m ) (58%) rather than biochemical limitations, which disagreed with "the JVr biochemical limitations" hypothesis proposed by Kumarathunge et al. (2019).</p></div>

ano.nymous@ccsd.cnrs.fr.invalid (Wei Xue) 08 Oct 2025

https://hal.inrae.fr/hal-05240498v1

[hal-03714709] A standardized morpho-functional classification of the planet's humipedons

It was time to take stock. We modified the humipedon classification key published in 2018 to make it easier and more practical. This morpho-functional taxonomy of the topsoil (humipedon) was only available in English; we also translated it into French and Italian. A standardized morpho-functional classification of humipedons (roughly the top 30–40 cm of soil: organic and organomineral surface horizons) would allow for a better understanding of the functioning of the soil ecosystem. This paper provides the founding principles of the classification of humipedon into humus systems and forms. With the recognition of a few diagnostic horizons, all humus systems can be determined. The humus forms that make up these humus systems are revealed by measuring the thicknesses of the diagnostic horizons. In the final part of the article, several figures represent the screenshots of a mobile phone or tablet application that allows for a fast recall of the diagnostic elements of the classification in the field. The article attempts to promote a standardized classification of humipedons for a global and shared management of soil at planet level.

ano.nymous@ccsd.cnrs.fr.invalid (Augusto Zanella) 11 Jul 2022

https://hal.science/hal-03714709v2

[hal-03981724] The response of mesophyll conductance to ozone-induced oxidative stress is genotype-dependent in poplar

Abbreviations: A net , net assimilation rate; Asc, ascorbate; C c , CO 2 partial pressure in the chloroplast; B L , contribution of biochemical limitation to the A net decrease; C i , intercellular CO 2 partial pressure; C i-C c , CO 2 drawdown from the intercellular airspace to chloroplasts; g s , stomatal conductance to water vapour; g sc , stomatal conductance to CO 2 ; J 1000 , electron transport rate at 1000 μmol m −2 s −1 PPFD; J max , maximum electron transport rate; LMA, leaf dry mass per area; l b , l m , l s , photosynthetic limitation by biochemistry, the mesophyll, stomatal conductance;MC L , contribution of mesophyll limitation to the A net decrease; MDA, malondialdehyde; S L , contribution of stomatal conductance limitation to the A net decrease; V cmax , maximum carboxylation rate of the Rubisco enzyme.

ano.nymous@ccsd.cnrs.fr.invalid (Ricardo Joffe) 04 May 2023

https://hal.univ-lorraine.fr/hal-03981724v1

[hal-03873631] High exposure of global tree diversity to human pressure

Safeguarding Earth’s tree diversity is a conservation priority due to the importance of trees for biodiversity and ecosystem functions and services such as carbon sequestration. Here, we improve the foundation for effective conservation of global tree diversity by analyzing a recently developed database of tree species covering 46,752 species. We quantify range protection and anthropogenic pressures for each species and develop conservation priorities across taxonomic, phylogenetic, and functional diversity dimensions. We also assess the effectiveness of several influential proposed conservation prioritization frameworks to protect the top 17% and top 50% of tree priority areas. We find that an average of 50.2% of a tree species’ range occurs in 110-km grid cells without any protected areas (PAs), with 6,377 small-range tree species fully unprotected, and that 83% of tree species experience nonnegligible human pressure across their range on average. Protecting high-priority areas for the top 17% and 50% priority thresholds would increase the average protected proportion of each tree species’ range to 65.5% and 82.6%, respectively, leaving many fewer species (2,151 and 2,010) completely unprotected. The priority areas identified for trees match well to the Global 200 Ecoregions framework, revealing that priority areas for trees would in large part also optimize protection for terrestrial biodiversity overall. Based on range estimates for &gt;46,000 tree species, our findings show that a large proportion of tree species receive limited protection by current PAs and are under substantial human pressure. Improved protection of biodiversity overall would also strongly benefit global tree diversity.

ano.nymous@ccsd.cnrs.fr.invalid (Wen-Yong Guo) 28 Nov 2022

https://hal.science/hal-03873631v1

[hal-03639012] Climate and ungulate browsing impair regeneration dynamics in spruce-fir-beech forests in the French Alps

Abstract Key message Different components of water balance and temperature reduce density and height growth of saplings of Picea abies (L.) H. Karst (Norway spruce), Abies alba Mill. (silver fir) and Fagus sylvatica L. (European beech) in mixed uneven-aged forests in the French Alps and Jura mountains. Ungulate browsing is an additional pressure on fir and beech that could jeopardise the renewal of these species in the future. Context The uncertainty in tree recruitment rates raises questions about the factors affecting regeneration processes in forests. Factors such as climate, light, competition and ungulate browsing pressure may play an important role in determining regeneration, forest structures and thus future forest composition. Aims The objective of this study was to quantify sapling densities and height increments of spruce, fir and beech and to identify dominant environmental variables influencing them in mixed uneven-aged forests in the French Alps and Jura mountains. Methods Sapling height increment and density were recorded in 152 plots, and non-linear mixed models were obtained to establish relations between them and environmental factors known to affect regeneration, namely altitude, slope, aspect, canopy openness, soil characteristics, temperature, precipitation and ungulate browsing. Results Regeneration density, varying from 0 to 7 saplings per m 2 , decreased with sapling height and was also negatively affected for spruce by PET, but positively for fir by precipitation and for beech by mean annual soil water content. Height increment reached up to 50 cm annually, increasing with sapling height and canopy openness and decreasing under high maximum summer temperatures for spruce and beech. The statistical effect of different environmental variables varied slightly among species but trends were quite similar. Additionally, ungulate browsing was high, with fir being the most intensely browsed, followed closely by beech, while spruce was rarely browsed. Conclusions All these results suggest that more temperature warming and a decrease in water availability could negatively impact sapling growth and density in the three species, with possible reduction of forest renewal fluxes. The observed increase of ungulate populations leading to increased browsing could be particularly detrimental to fir saplings.

ano.nymous@ccsd.cnrs.fr.invalid (Mithila Unkule) 12 Apr 2022

https://hal.inrae.fr/hal-03639012v1

[hal-03638143] Historical landscape matters for threatened species in French mountain forests

Ancient forests are known to host a biodiversity of high ecological distinctiveness and are likely to provide habitat for red-listed species. Yet, few studies have investigated the role of forest continuity for the conservation of threatened species. We used species-presence data on red-listed species from 12 taxonomic groups (Spermatophyta, Pteridophyta, Bryophyta, Lichens, Chiroptera, Aves, Squamata, Amphibia, Coleoptera, Lepidoptera, Odonata and Orthoptera) to ascertain if ancient forests are an important habitat for threatened species in five mountain and subalpine protected areas in France. We compared the effect of the amount of historical forest (1853–1860) with the effect of the amount of current forest on the distribution of red-listed species in six circular landscape buffers ranging in radius from 100 to 1500 m. We showed that the amount of historical forest in the landscape had a positive effect on forest Spermatophyta, Bryophyta, Coleoptera and edge forest Pteridophyta with a better predictive power than current forest area, highlighting a colonization credit in recent forests. Conversely, edge-forest lepidopterans were more negatively affected by historical than by current forest area, highlighting an extinction debt in recent forests. Our findings underline that implementing protective measures of ancient forests would be a better strategy than afforestation to preserve threatened forest species in mountain and subalpine forest landscapes.

ano.nymous@ccsd.cnrs.fr.invalid (Sylvain Mollier) 23 Nov 2023

https://hal.inrae.fr/hal-03638143v1

[hal-03518443] Global maps of soil temperature

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km² resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e., offset) between in-situ soil temperature measurements, based on time series from over 1200 1-km² pixels (summarized from 8500 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in-situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications.

ano.nymous@ccsd.cnrs.fr.invalid (Jonas Lembrechts) 03 Mar 2022

https://hal.science/hal-03518443v1

[hal-03846703] Stronger legacy effects of cropland than of meadows or pastures on soil conditions and plant communities in French mountain forests

Question Differences in understory vegetation between ancient and recent forests have been thoroughly explored; however, few studies have investigated the legacies of different former land uses in recent forests. Indeed, due to more intense agricultural practices (tillage and fertilisation), legacy effects are expected to be stronger in former cropland or meadows than in former pastures. Our objectives were to compare soil conditions, taxonomic composition and functional composition of understory plant communities in recent forests located on former pastures, meadows or cropland, with ancient forests as a reference.LocationTarentaise Valley, Savoy, France Methods Based on land-use maps surveyed between 1862 and 1864, we selected 82 forest sites with different former land uses in mountain forests in the French Alps and carried out soil sampling and botanical surveys. To account for potential confounding factors (altitude, canopy cover, tree species composition), we applied multiple linear regressions to analyse soil properties, canonical correspondence analysis to analyse plant taxonomic composition and multi-species generalized linear mixed-effects models to analyse relationships between plant functional composition and former land uses. Results The soils of former cropland were richer in nutrients and more alkaline compared to other past land uses, while soils on former pastures and meadows differed only slightly from ancient forests. Ancient forests were characterised by acidophilic, shade-tolerant, low-stature, forest-dependent species, whereas former cropland was characterised by calcicolous non-forest species. Former pasture and meadow communities displayed a distinct taxonomic composition compared to other past land uses, but a functional composition closer to ancient forest than to former cropland. Conclusion Former cropland has a stronger legacy effect than former pastures or meadows. This could explain small differences between ancient and recent forests observed in previous studies conducted in mountain landscapes where former cropland was rare.

ano.nymous@ccsd.cnrs.fr.invalid (Sylvain Mollier) 23 Nov 2023

https://hal.inrae.fr/hal-03846703v1

[hal-03502713] Uncovering the critical soil moisture thresholds of plant water stress for European ecosystems

Understanding the critical soil moisture (SM) threshold (θcrit) of plant water stress and land surface energy partitioning is a basis to evaluate drought impacts and improve models for predicting future ecosystem condition and climate. Quantifying the θcrit across biomes and climates is challenging because observations of surface energy fluxes and SM remain sparse. Here, we used the latest database of eddy covariance measurements to estimate θcrit across Europe by evaluating evaporative fraction (EF)-SM relationships and investigating the covariance between vapor pressure deficit (VPD) and gross primary production (GPP) during SM dry-down periods. We found that the θcrit and soil matric potential threshold in Europe are 16.5% and −0.7 MPa, respectively. Surface energy partitioning characteristics varied among different vegetation types; EF in savannas had the highest sensitivities to SM in water-limited stage, and the lowest in forests. The sign of the covariance between daily VPD and GPP consistently changed from positive to negative during dry-down across all sites when EF shifted from relatively high to low values. This sign of the covariance changed after longer period of SM decline in forests than in grasslands and savannas. Estimated θcrit from the VPD–GPP covariance method match well with the EF–SM method, showing this covariance method can be used to detect the θcrit. We further found that soil texture dominates the spatial variability of θcrit while shortwave radiation and VPD are the major drivers in determining the spatial pattern of EF sensitivities. Our results highlight for the first time that the sign change of the covariance between daily VPD and GPP can be used as an indicator of how ecosystems transition from energy to SM limitation. We also characterized the corresponding θcrit and its drivers across diverse ecosystems in Europe, an essential variable to improve the representation of water stress in land surface models.

ano.nymous@ccsd.cnrs.fr.invalid (Zheng Fu) 25 Sep 2025

https://hal.science/hal-03502713v1

[hal-04895169] Bark composition changes along the trunk of three softwood species: Picea abies , Abies alba Mill. and Pseudotsuga menziesii

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ano.nymous@ccsd.cnrs.fr.invalid (Clément Fritsch) 17 Jan 2025

https://hal.univ-lorraine.fr/hal-04895169v1

[hal-03757303] Comparative Copper Resistance Strategies of Rhodonia placenta and Phanerochaete chrysosporium in a Copper/Azole-Treated Wood Microcosm

Copper-based formulations of wood preservatives are widely used in industry to protect wood materials from degradation caused by fungi. Wood treated with preservatives generate toxic waste that currently cannot be properly recycled. Despite copper being very efficient as an antifungal agent against most fungi, some species are able to cope with these high metal concentrations. This is the case for the brown-rot fungus Rhodonia placenta and the white-rot fungus Phanerochaete chrysospo- rium, which are able to grow efficiently in pine wood treated with Tanalith E3474. Here, we aimed to test the abilities of the two fungi to cope with copper in this toxic environment and to decontaminate Tanalith E-treated wood. A microcosm allowing the growth of the fungi on industrially treated pine wood was designed, and the distribution of copper between mycelium and wood was analysed within the embedded hyphae and wood particles using coupled X-ray fluorescence spectroscopy and Scanning Electron Microscopy (SEM)/Electron Dispersive Spectroscopy (EDS). The results demon- strate the copper biosorption capacities of P. chrysosporium and the production of copper-oxalate crystals by R. placenta. These data coupled to genomic analysis suggest the involvement of additional mechanisms for copper tolerance in these rot fungi that are likely related to copper transport (import, export, or vacuolar sequestration).

ano.nymous@ccsd.cnrs.fr.invalid (Gaurav Pandharikar) 22 Aug 2022

https://hal.inrae.fr/hal-03757303v1

[hal-03863446] Genotypic and tissue-specific variation of Populus nigra transcriptome profiles in response to drought

Climate change is one of the most important challenges for mankind in the far and near future. In this regard, sustainable production of woody crops on marginal land with low water availability is a major challenge to tackle. This dataset is part of an experiment, in which we exposed three genetically differentiated genotypes of Populus nigra originating from contrasting natural habitats to gradually increasing moderate drought. RNA sequencing was performed on fine roots, developing xylem and leaves of those three genotypes under control and moderate drought conditions in order to get a comprehensive dataset on the transcriptional changes at the whole plant level under water limiting conditions. This dataset has already provided insight in the transcriptional control of saccharification potential of the three Populus genotypes under drought conditions and we suggest that our data will be valuable for further in-depth analysis regarding candidate gene identification or, on a bigger scale, for meta-transcriptome analysis.

ano.nymous@ccsd.cnrs.fr.invalid (Christian Eckert) 30 Jun 2024

https://hal.inrae.fr/hal-03863446v1

[hal-03880254] The 2018 European heatwave led to stem dehydration but not to consistent growth reductions in forests

Abstract Heatwaves exert disproportionately strong and sometimes irreversible impacts on forest ecosystems. These impacts remain poorly understood at the tree and species level and across large spatial scales. Here, we investigate the effects of the record-breaking 2018 European heatwave on tree growth and tree water status using a collection of high-temporal resolution dendrometer data from 21 species across 53 sites. Relative to the two preceding years, annual stem growth was not consistently reduced by the 2018 heatwave but stems experienced twice the temporary shrinkage due to depletion of water reserves. Conifer species were less capable of rehydrating overnight than broadleaves across gradients of soil and atmospheric drought, suggesting less resilience toward transient stress. In particular, Norway spruce and Scots pine experienced extensive stem dehydration. Our high-resolution dendrometer network was suitable to disentangle the effects of a severe heatwave on tree growth and desiccation at large-spatial scales in situ, and provided insights on which species may be more vulnerable to climate extremes.

ano.nymous@ccsd.cnrs.fr.invalid (Roberto Salomón) 01 Dec 2022

https://agroparistech.hal.science/hal-03880254v1

[hal-03518448] Tropical and subtropical Asia's valued tree species under threat

Tree diversity in Asia’s tropical and subtropical forests is central to nature-based solutions. Species vulnerability to multiple threats, which affectstheprovision of ecosystem services,is poorly understood. We conducteda region-wide, spatially explicit vulnerability assessment(including overexploitation, fire, overgrazing, habitat conversion, andclimate change) of63socio-economically important tree speciesselected from national priority lists and validated by anexpert network representing20 countries. Overall, 74% of the most important areas for conservation of these trees fall outside of protected areas, with species severelythreatened across 47% of their native ranges. The most imminent threats areoverexploitation and habitat conversion, with populations being severely threatened in an average of 24% and 16% of their distribution areas. Optimistically, our results predict relativelylimited overall climate change impacts, however, some of thestudy species arelikelyto lose more than 15% of their habitat by 2050 because of climate change. We pinpoint specific natural forest areas in Malaysia and Indonesia(Borneo) as hotspots for on-site conservationof forest genetic resources, more than 82% of which do not currently fall within designated protected areas. We also identify degraded lands in Indonesia (Sumatra) as priorities for restoration where planting or assisted natural regeneration will help maintain these species into the future, while croplands in Southern India are highlighted as potentially important agroforestry options.Our study highlights the need for regionally coordinated action for effective conservation and restoration.

ano.nymous@ccsd.cnrs.fr.invalid (Hannes Gaisberger) 09 Jan 2022

https://hal.science/hal-03518448v1

[hal-04033784] Plant invasion modifies isohydricity in Mediterranean tree species

Understanding of plant hydraulic strategies (i.e. the degree of iso-/anisohydricity) is crucial to predict the response of plants to changing environmental conditions such as climate-change induced extreme drought. Several abiotic factors, including evaporative demand, have been shown to seasonally modify the isohydricity of plants. However, the impact of biotic factors such as plant-plant interactions on hydraulic strategies has seldom been explored. Here, we investigated adaptations and changes in hydraulic strategies of two woody species in response to seasonal abiotic conditions, experimental drought and plant invasion in a Mediterranean cork oak (Quercus suber) ecosystem with a combined shrub invasion (Cistus ladanifer) and rain exclusion experiment. From the dry to wet season, Q. suber shifted from a partial isohydric to an anisohydric behaviour while C. ladanifer shifted from strict anisohydric to partial isohydric. During drought, water competition by plant invasion significantly modified the hydraulic strategy of invaded Q. suber, which was accompanied by lower pre-dawn leaf water potentials, sap flow density, leaf area index and trunk increment rates. This altered isohydricity of invaded Q. suber trees was most likely caused by interspecific competition for water resources by water spending C. ladanifer shrubs. Both species do have the highest proportion of fine roots in the topsoil and thus, an additional water consumer, such as C. ladanifer can lead to more stressful conditions for Q. suber during times of water scarcity. Further underlying mechanisms of the altered isohydricity of Q. suber, such as potential allelopathic effects of C. ladanifer exudates on root growth of Q. suber, have to be investigated in the future. In conclusion, we demonstrate that the degree of isohydricity of two woody Mediterranean plant species is dynamically determined by the interplay of species-specific hydraulic traits and their abiotic and biotic environment. Read the free Plain Language Summary for this article on the Journal blog.

ano.nymous@ccsd.cnrs.fr.invalid (Simon Haberstroh) 17 Mar 2023

https://hal.inrae.fr/hal-04033784v1

[hal-03619993] Embedding non-industrial private forest owners in forest policy and bioeconomy issues using a Living Lab concept

International policies have set sustainable development goals that put emphasis on bioeconomy strategies based on renewable resources. The forestry sector, by providing bio-based products, is expected to take part in this bioeconomy with, among other things, the reduction of society's dependence on fossil fuels. Nevertheless, in Europe, the forestry sector is facing an increase in the number of small private forest ownerships, called non-industrial private forests (NIPF), where wood mobilization is difficult due to both ownership fragmentation and the lack of interest of non-industrial forest owners in existing forest-wood chains. Although many policy instruments have been put in place to address this situation, the problem persists for two main reasons. First, a lack of use of policy instruments by forest owners and second, a lack of collaboration between stakeholders. To provide solutions, we propose a methodology to design territorial projects with non-industrial forest owners in the framework of a Living Lab innovation process. This paper presents both the general method developed and analyzed through open and user-centered innovation concepts and its practical implementation in the Vosges department in France. Our results show how the Living Lab approach can improve the acceptance, adoption and use of policy instruments by NIPF owners and how it promotes multi-stakeholder collaborations to design and deploy innovative solutions. The main interest of our study is to provide a methodology to pilot a forestry Living Lab for policy makers and practitioners, based on rigorous concepts of innovation management. Finally, future developments and limitations of our study are discussed in a global research perspective.

ano.nymous@ccsd.cnrs.fr.invalid (Maxence Arnould) 04 Jan 2024

https://hal.science/hal-03619993v1

[hal-03468938] CNN-based Method for Segmenting Tree Surface Singularites

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ano.nymous@ccsd.cnrs.fr.invalid (Florian Delconte) 21 May 2025

https://hal.science/hal-03468938v1

[hal-04327109] A review of the heterogeneous landscape of biodiversity databases: opportunities and challenges for a synthesized biodiversity knowledge base

Aim Addressing global environmental challenges requires access to biodiversity data across wide spatial, temporal and taxonomic scales. Availability of such data has increased exponentially recently with the proliferation of biodiversity databases. However, heterogeneous coverage, protocols, and standards have hampered integration among these databases. To stimulate the next stage of data integration, here we present a synthesis of major databases, and investigate (a) how the coverage of databases varies across taxonomy, space, and record type; (b) what degree of integration is present among databases; (c) how integration of databases can increase biodiversity knowledge; and (d) the barriers to database integration. Location Global. Time period Contemporary. Major taxa studied Plants and vertebrates. Methods We reviewed 12 established biodiversity databases that mainly focus on geographic distributions and functional traits at global scale. We synthesized information from these databases to assess the status of their integration and major knowledge gaps and barriers to full integration. We estimated how improved integration can increase the data coverage for terrestrial plants and vertebrates. Results Every database reviewed had a unique focus of data coverage. Exchanges of biodiversity information were common among databases, although not always clearly documented. Functional trait databases were more isolated than those pertaining to species distributions. Variation and potential incompatibility of taxonomic systems used by different databases posed a major barrier to data integration. We found that integration of distribution databases could lead to increased taxonomic coverage that corresponds to 23 years’ advancement in data accumulation, and improvement in taxonomic coverage could be as high as 22.4% for trait databases. Main conclusions Rapid increases in biodiversity knowledge can be achieved through the integration of databases, providing the data necessary to address critical environmental challenges. Full integration across databases will require tackling the major impediments to data integration: taxonomic incompatibility, lags in data exchange, barriers to effective data synchronization, and isolation of individual initiatives.

ano.nymous@ccsd.cnrs.fr.invalid (Xiao Feng) 19 Feb 2025

https://hal.inrae.fr/hal-04327109v1

[hal-05167356] Réseau ESPERENSE : une évaluation participative des essences de demain

Le projet ESPERENSE est achevé, vive le réseau ESPERENSE ! Un réseau de sites expérimentaux répondant à la stratégie et aux principes définis dans le projet mais aussi une communauté d’expérimentateurs très investis, chacun à son niveau, de la recherche à la gestion forestière…

ano.nymous@ccsd.cnrs.fr.invalid (Eric Paillassa) 17 Jul 2025

https://hal.science/hal-05167356v1

[hal-03926055] With increasing site quality asymmetric competition and mortality reduces Scots pine (Pinus sylvestris L.) stand structuring across Europe

Heterogeneity of structure can increase mechanical stability, stress resistance and resilience, biodiversity and many other functions and services of forest stands. That is why many silvicultural measures aim at enhancing structural diversity. However, the effectiveness and potential of structuring may depend on the site conditions. Here, we revealed how the stand structure is determined by site quality and results from site-dependent partitioning of growth and mortality among the trees. We based our study on 90 mature, even-aged, fully stocked monocultures of Scots pine (Pinus sylvestris L.) sampled in 21 countries along a productivity gradient across Europe. A mini-simulation study further analyzed the site-dependency of the interplay between growth and mortality and the resulting stand structure. The overarching hypothesis was that the stand structure changes with site quality and results from the site-dependent asymmetry of competition and mortality.First, we show that Scots pine stands structure across Europe become more homogeneous with increasing site quality. The coefficient of variation and Gini coefficient of stem diameter and tree height continuously decreased, whereas Stand Density Index and stand basal area increased with site index.Second, we reveal a site-dependency of the growth distribution among the trees and the mortality. With increasing site index, the asymmetry of both competition and growth distribution increased and suggested, at first glance, an increase in stand heterogeneity. However, with increasing site index, mortality eliminates mainly small instead of all-sized trees, cancels the size variation and reduces the structural heterogeneity.Third, we modelled the site-dependent interplay between growth partitioning and mortality. By scenario runs for different site conditions, we can show how the site-dependent structure at the stand level emerges from the asymmetric competition and mortality at the tree level and how the interplay changes with increasing site quality across Europe.Our most interesting finding was that the growth partitioning became more asymmetric and structuring with increasing site quality, but that the mortality eliminated predominantly small trees, reduced their size variation and thus reversed the impact of site quality on the structure. Finally, the reverse effects of mode of growth partitioning and mortality on the stand structure resulted in the highest size variation on poor sites and decreased structural heterogeneity with increasing site quality. Since our results indicate where heterogeneous structures need silviculture interventions and where they emerge naturally, we conclude that these findings may improve system understanding and modelling and guide forest management aiming at structurally rich forests.

ano.nymous@ccsd.cnrs.fr.invalid (Hans Pretzsch) 06 Jan 2025

https://hal.science/hal-03926055v1

[hal-03519397] Do trait responses to simulated browsing in Quercus robur saplings affect their attractiveness to Capreolus capreolus the following year?

With the rise of large herbivore populations in most northern hemisphere forests, browsing is becoming an increasingly important driver of forest regeneration dynamics. Among other processes affecting the regeneration, the concept of plant-herbivore feedback loops holds that browsed saplings are more subject to subsequent herbivory. This phenomenon is interpreted as a consequence of compensatory growth following browsing since fast growth is generally associated with higher digestibility and lower defense against herbivores. However, studies linking browsing-induced trait variations to subsequent attractiveness to herbivores are still lacking, especially in the forest context. In this study, we experimentally examine the existence of a feedback loop between oak (Quercus robur L.) and roe deer (Capreolus capreolus) and investigate its underlying morphological and chemical traits. We simulated single and repeated roe deer browsing on nursery-grown oak saplings and measured the changes in sapling height growth, lateral branching, leaf traits and winter shoot traits over two years. We conducted winter feeding trials with tame roe deer one year after the first treatment to test the effect of simulated browsing on sapling attractiveness. Simulated browsing reduced sapling height growth but had no effect on branching. Simulated browsing had no effect on leaf traits after half a year, but decreased the phenolic content and increased the fiber content of winter shoots the following winter. Contrary to our predictions, roe deer preferentially browsed control saplings over saplings previously browsed. After two years, repeated browsing promoted fast carbon acquisition leaf traits (high chlorophyll, high specific leaf area and low fiber content), reduced leaf phenolic content and increased leaf digestibility. We showed that a reduction in 1-year-old oak sapling height growth following browsing, combined with increased structural defense at the expense of chemical defense in winter shoots the following winter, was correlated with reduced browsing pressure, thereby challenging the feedback loop hypothesis. However, we also demonstrated that repeated browsing promoted fast carbon acquisition leaf traits in 2.5-year-old saplings, which tend to support the existence of a feedback loop on older and more intensively browsed saplings. As such, our study provides empirical evidence that morphological and physiological trait responses to browsing influence oak sapling attractiveness, but that the direction and magnitude of this effect depend on the ontogenic stage of the sapling and on the number of browsing events.

ano.nymous@ccsd.cnrs.fr.invalid (Julien Barrere) 05 Jan 2024

https://hal.inrae.fr/hal-03519397v1

[hal-03829175] PSDR4 ASTRAL - Acteurs et Services écosystémiques des Territoires RurAux Lorrains

Des enjeux forts de valorisation des ressources territoriales sont posés en Lorraine qui place en interaction cultures, élevages, forêts, zones de friches et zones urbanisées. ASTRAL s’est interrogé sur les complémentarités à rechercher entre usages des sols pour produire une diversité de services écosystémiques, sur les représentations associées à ces services ainsi que sur les dispositifs d’action collective et les réseaux d’acteurs qui impulsent, accompagnent ou freinent les dynamiques territoriales. La démarche méthodologique a combiné analyses quantitatives et cartographiques de bases de données géographiques, observations de terrain et expérimentations, mesures de services en parcelles, enquêtes qualitatives et situations d’observation participante. Outre des travaux conduits à l’échelle régionale, cette démarche a été déployée dans trois études de cas territoriales, lieux de différentes formes d’interactions avec les acteurs locaux et les habitants. ASTRAL a produit de nouvelles connaissances sur les organisations et dynamiques territoriales des usages des sols aux échelles régionale et territoriale, sur les mécanismes à l’origine de la fourniture de services écosystémiques ainsi que sur les organisations sociales qu’ils suscitent, qui dépendent étroitement des contextes politiques et économiques locaux. Le projet a notamment montré que les friches, qu’elles soient naturelles ou industrielles, peuvent être des lieux d’expérimentations scientifiques, sociales, culturelles afin d’encourager la réappropriation de leurs territoires par les riverains. Il a aussi mis en évidence le rôle déterminant des associations qui, proches des populations, construisent des problématiques sociales qui touchent l’environnement, l’alimentation et la ruralité, et permettent la structuration de mobilisations inédites en milieu rural pour favoriser une transition agroécologique de l’agriculture incluant une reconnexion avec l’alimentation.

ano.nymous@ccsd.cnrs.fr.invalid (Catherine Mignolet) 25 Oct 2022

https://hal.inrae.fr/hal-03829175v1

[hal-03919731] Dendrometric data from the silvicultural scenarios developed by Office National des Forêts (ONF) in France: a tool for applied research and carbon storage estimates

We provide a database of 52 silvicultural scenarios recommended in French public forests including relevant dendrometric variables and metrics for carbon accounting. The dataset is available at https://doi.org/10.57745/QARRFS . Associated metadata are available at https://metadata-afs.nancy.inra.fr/geonetwork/srv/fre/catalog.search#/metadata/f76ed27f-325d-493b-8731-0995dcaa7805 . Special attention was paid to offer carbon metrics required for the French Label Bas Carbone offset projects.

ano.nymous@ccsd.cnrs.fr.invalid (Salomé Fournier) 04 Jul 2023

https://agroparistech.hal.science/hal-03919731v1

[hal-03926054] Identification and spatial extent of understory plant species requiring vegetation control to ensure tree regeneration in French forests

Abstract Key message Fifteen species are most susceptible to require vegetation control during tree regeneration in the range of our study. Among these 15 species, Rubus fruticosus , Pteridium aquilinum , and Molinia caerulea cover each more than 300,000 ha of open-canopy forests. Context Vegetation control, i.e., the reduction of competitive species cover, is often required to promote tree seedling establishment during the forest regeneration stage. The necessity to control understory vegetation largely depends on the species to be controlled. In order to plan forest renewal operations, it is critical to identify which species require vegetation control during the regeneration stage and to quantify the forest area affected by these species. Aims We aimed at identifying the main species requiring vegetation control and at estimating the forest area they cover at the national level. Methods Using National Forest Inventory data, we created four indicators based on two levels of plant cover, cross-referenced with two levels of canopy opening, and compared them to the outcome of a survey of forest manager practices. Results The best indicator was the one that represented the proportion of forests with open canopy where the species was present with a large cover in the understory. In non-Mediterranean France, according to the indicator, a total of 15 species were found to frequently require vegetation control during the tree regeneration stage. Pteridium aquilinum , Molinia caerulea , and Rubus fruticosus were the main species, and each covered more than 300,000 ha of forest with open canopies, representing about 13% of the total forest area with open canopies outside of the Mediterranean area. Conclusions Forests covered by species requiring vegetation control according to forest managers represent a large share of the forest area undergoing regeneration. This study provides the first list of species that require vegetation control based on a methodological protocol that makes it possible to calculate the area associated with each species.

ano.nymous@ccsd.cnrs.fr.invalid (Noé Dumas) 02 Feb 2023

https://hal.science/hal-03926054v1

[hal-03926053] The distribution of carbon stocks between tree woody biomass and soil differs between Scots pine and broadleaved species (beech, oak) in European forests

While the impacts of forest management options on carbon (C) storage are well documented, the way they affect C distribution among ecosystem components remains poorly investigated. Yet, partitioning of total forest C stocks, particularly between aboveground woody biomass and the soil, greatly impacts the stability of C stocks against disturbances in forest ecosystems. This study assessed the impact of species composition and stand density on C storage in aboveground woody biomass (stem + branches), coarse roots, and soil, and their partitioning in pure and mixed forests in Europe. We used 21 triplets (5 beech-oak, 8 pine-beech, 8 pine-oak mixed stands, and their respective monocultures at the same sites) in seven European countries. We computed biomass C stocks from total stand inventories and species-specific allometric equations, and soil organic C data down to 40 cm depth. On average, the broadleaved species stored more C in aboveground woody biomass than soil, while C storage in pine was equally distributed between both components. Stand density had a strong effect on C storage in tree woody biomass but not in the soil. After controlling for stand basal area, the mixed stands had, on average, similar total C stocks (in aboveground woody biomass + coarse roots + soil) to the most performing monocultures. Although species composition and stand density affect total C stocks and its partitioning between aboveground woody biomass and soil, a large part of variability in soil C storage was unrelated to stand characteristics.

ano.nymous@ccsd.cnrs.fr.invalid (Richard Osei) 25 Oct 2023

https://hal.science/hal-03926053v1

[hal-03654545] Estimating natural background concentrations for dissolved constituents in groundwater: A methodological review and case studies for geogenic fluoride

Knowledge of the natural background concentrations of groundwater constituents is important for the management of groundwater resources, particularly for the assessment of groundwater contamination and the establishment of clean-up goals and regulatory target levels. In recent years, an increasing number of studies have assessed the natural background concentrations of dissolved constituents in groundwater using a variety of different methods, each with its own assumptions, advantages and limitations. The objective of this paper is to provide a methodological basis for improving the estimation of natural background concentrations of groundwater constituents. To this end, this paper critically reviews the different approaches used to determine natural background concentrations of dissolved constituents in groundwater. In addition, two regional case studies of fluoride in Canadian groundwater are presented to illustrate the estimation of background concentrations for natural groundwater constituents. The review of existing methods shows that the use of pristine groundwater samples is not possible in many cases, due to the widespread influence of human activities. The widely used pre-selection method can provide misleading results because of inadequate selection criteria and poor statistical significance associated with the reduction of the dataset. A variety of model-based methods have been developed, but these methods are all based on assumptions that cannot be verified. Relying on the user's experience and previous knowledge of the groundwater system, exploratory data analysis has many advantages and can be applied for both anthropogenic and natural constituents. The case studies show that the exploratory data analysis approach provides critical information to determine the sources of groundwater constituents and to properly delineate groundwater bodies for which background values will be established. Natural background concentrations should always be considered as theoretical values due to their spatio-temporal variability and scale dependence, and thresholds as concentration values above which further investigation is required.

ano.nymous@ccsd.cnrs.fr.invalid (Raphaël Bondu) 05 Jan 2024

https://brgm.hal.science/hal-03654545v1

[hal-03643415] A limited number of species is sufficient to assign a vegetation plot to a forest vegetation unit

Aims: Inventorying the habitats composing Natura 2000 sites is mandatory in the European Union and is necessary to implement relevant conservation measures. Vegetation plots, recording the presence or abundance of all plant species co-occurring within a plot, are currently used to identify terrestrial Natura 2000 habitat types, whose descriptions are mainly based on phytosociological units. However, vegetation plots are time-consuming and frequently restricted to the growing season. Moreover, no vegetation plots can be regarded as exhaustive, and significant inter-observer variation has been highlighted. We studied whether reducing the number of recorded species and the time spent carrying out a vegetation plot had an impact on vegetation unit assignment using species presence. We also studied if vegetation plots recorded in winter could be used for vegetation unit assignment. Location: Mainland France. Methods: We used 273 vegetation plots covering French temperate and mountainous forests. The time at which species were sighted was recorded. We also estimated whether a species was recognisable in winter. We used a classification program to compare assignments based on complete and incomplete vegetation plots. Results: Ten species and five minutes were sufficient to assign a plot to an association, and to an alliance, seven species and four minutes. Vegetation unit assignment proved feasible in winter, especially at the alliance level. Conclusions: We confirmed that a limited number of species is sufficient to assign vegetation plots to vegetation units. However, mapping habitats requires habitat identification and delimitation. This study confirms current field habits, particularly when creating a habitat map, usually based on a limited number of recorded species. Lastly, it confirms that the use of vegetation plots coming from a great variety of sources is relevant to create habitat time series, crucial tools for monitoring habitats at a national scale.

ano.nymous@ccsd.cnrs.fr.invalid (Lise Maciejewski) 15 Apr 2022

https://hal.science/hal-03643415v1

[hal-03860136] Plant root growth against a mechanical obstacle: the early growth response of a maize root facing an axial resistance is consistent with the Lockhart model

Plant root growth is dramatically reduced in compacted soils, affecting the growth of the whole plant. Through a model experiment coupling force and kinematics measurements, we probed the force–growth relationship of a primary root contacting a stiff resisting obstacle, which mimics the strongest soil impedance variation encountered by a growing root. The growth of maize roots just emerging from a corseting agarose gel and contacting a force sensor (acting as an obstacle) was monitored by time-lapse imaging simultaneously to the force. The evolution of the velocity field along the root was obtained from kinematics analysis of the root texture with a particle image velocimetry derived technique. A triangular fit was introduced to retrieve the elemental elongation rate or strain rate. A parameter-free model based on the Lockhart law quantitatively predicts how the force at the obstacle modifies several features of the growth distribution (length of the growth zone, maximal elemental elongation rate and velocity) during the first 10 min. These results suggest a strong similarity of the early growth responses elicited either by a directional stress (contact) or by an isotropic perturbation (hyperosmotic bath).

ano.nymous@ccsd.cnrs.fr.invalid (Manon Quiros) 18 Nov 2022

https://hal.science/hal-03860136v1

[hal-03658479] Traceability and quality assessment of Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) logs: the TreeTrace_Douglas database

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ano.nymous@ccsd.cnrs.fr.invalid (Fleur Longuetaud) 31 Jan 2023

https://hal.science/hal-03658479v1

[hal-03736228] Non-structural carbohydrates and morphological traits of leaves, stems and roots from tree species in different climates

Objectives: Carbon fixed during photosynthesis is exported from leaves towards sink organs as non-structural carbohydrates (NSC), that are a key energy source for metabolic processes in trees. In xylem, NSC are mostly stored as soluble sugars and starch in radial and axial parenchyma. The multi-functional nature of xylem means that cells possess several functions, including water transport, storage and mechanical support. Little is known about how NSC impacts xylem multi-functionality, nor how NSC vary among species and climates. We collected leaves, stem and root xylem from tree species growing in three climates and estimated NSC in each organ. We also measured xylem traits linked to hydraulic and mechanical functioning. Data description: The paper describes functional traits in leaves, stems and roots, including NSC, carbon, nitrogen, specific leaf area, stem and root wood density and xylem traits. Data are provided for up to 90 angiosperm species from temperate, Mediterranean and tropical climates. These data are useful for understanding the trade-offs in resource allocation from a whole-plant perspective, and to better quantify xylem structure and function related to water transportation, mechanical support and storage. Data will also give researchers keys to understanding the ability of trees to adjust to a changing climate.

ano.nymous@ccsd.cnrs.fr.invalid (Guangqi Zhang) 22 Jul 2022

https://hal.inrae.fr/hal-03736228v1

[hal-03952012] Leaf and tree water-use efficiencies of Populus deltoides × P. nigra in mixed forest and agroforestry plantations

In a global context where water will become a scarce resource under temperate latitudes, managing tree plantations with species associations, i.e., forest mixture or agroforestry, could play a major role in optimizing the sustainable use of this resource. Conceptual frameworks in community ecology suggest that, in mixed plantations, environmental resources such as water may be more efficiently used for carbon acquisition and tree growth thanks to niche complementarity among species. To test the hypotheses behind these conceptual frameworks, we estimated water-use efficiency (WUE) for poplar trees grown in a monoculture, in association with alder trees (forest mixture) and in association with clover leys (agroforestry) in an experimental plantation located in northeastern France. Water-use efficiency was estimated (i) at leaf level through gas exchange measurements and analysis of carbon isotope composition, (ii) at wood level through carbon isotope composition and (iii) at tree level with sap flow sensors and growth increment data. We hypothesized that species interactions would increase WUE of poplars in mixtures due to a reduction in competition and/or facilitation effects due to the presence of the N2-fixing species in mixtures. Poplar trees in both mixture types showed higher WUE than those in the monoculture. The differences we found in WUE between the monoculture and the agroforestry treatment were associated to differences in stomatal conductance and light-saturated net CO2 assimilation rate (at the leaf level) and transpiration (at the tree level), while the differences between the monoculture and the forest mixture were more likely due to differences in stomatal conductance at the leaf level and both transpiration and biomass accumulation at the tree level. Moreover, the more WUE was integrated in time (instantaneous gas exchanges &lt; leaf life span &lt; seasonal wood core &lt; whole tree), the more the differences among treatments were marked.

ano.nymous@ccsd.cnrs.fr.invalid (Anaïs Thomas) 23 Jan 2023

https://hal.science/hal-03952012v1

[hal-04019710] Provenance Differences in Water-Use Efficiency Among Sessile Oak Populations Grown in a Mesic Common Garden

Context As a widespread species, sessile oak ( Quercus petraea ) populations occupy a wide range of ecological conditions, with large gradients of soil water availability. Drought acclimation involves a plastic increase in water-use efficiency (WUE), a trait that is easily measured using the carbon isotope composition (δ 13 C). However, the question remains whether WUE is an adaptive trait that impacts the fitness of trees in natural environments. Objectives and Methods To investigate whether WUE was a drought-adaptive trait, we studied a sample of 600 trees originating from 16 provenances, grown for 21 years in a common garden. Intrinsic WUE (WUE i ), estimated from tree ring δ 13 C, was compared among and within populations for three climatically contrasted years. The adaptive character of WUE i was evaluated by relating population mean WUE i , as well as its plasticity to drought, to the pedoclimatic conditions of their provenance sites. The contribution of WUE i to tree and population fitness was finally assessed from the relationship between WUE i and tree radial growth (GI). Results Significant differences in WUE i were found among populations but a much larger variability was observed within than among populations. The population WUE i of the juvenile oak trees growing in the relatively mesic conditions of the common garden showed no relationship with a modeled water deficit index for the provenance sites. However, a higher population WUE i plasticity to severe drought was related to a higher proportion of silt and carbon and a lower proportion of sand in the soil of the provenance sites. In response to severe drought, populations with a higher increase in WUE i showed a lower decrease in GI. Populations with lower GI reduction were from sites with higher vapor pressure deficit in May–July (VPD). For the wet year only, populations with a higher WUE i also had a higher GI. Conclusion The correlations observed at the common garden site between (i) population means of WUE i plasticity to drought and soil texture of the provenance sites, and (ii) GI plasticity to drought and VPD, suggested a local adaptation of sessile oak.

ano.nymous@ccsd.cnrs.fr.invalid (Arivoara Rabarijaona) 13 Mar 2023

https://hal.inrae.fr/hal-04019710v1

[hal-03681553] Pit Characters Determine Drought-Induced Embolism Resistance of Leaf Xylem across 18 Neotropical Tree Species

Embolism spreading in xylem is an important component of plant drought resistance. Since embolism resistance has been shown to be mechanistically linked to pit membrane characters in stem xylem, we speculate that similar mechanisms account for leaf xylem. We conducted transmission electron microscopy to investigate pit membrane characters in leaf xylem across 18 Neotropical tree species. We also conducted gold perfusion and polar lipid detection experiments on three species covering the full range of leaf embolism resistance. We then related these observations to previously published data on embolism resistance of leaf xylem. We also incorporated previously published data on stem embolism resistance and stem xylem pit membranes to investigate the link between vulnerability segmentation (i.e., difference in embolism resistance) and leaf-stem anatomical variation. Pit membrane thickness (Tpm,max) and the pit membrane thickness-to-diameter ratio (Tpm,max/Dpm) were predictive of leaf embolism resistance, especially when vestured pits were taken into account. Variation in Tpm,max/Dpm was the only trait predictive of vulnerability segmentation between leaves and stems. Gold particles of 5 and 10 nm infiltrated pit membranes in three species, while the entry of 50-nm particles was blocked. Moreover, polar lipids were associated with inner conduit walls and pits. Our results suggest that mechanisms related to embolism spreading are determined by pit membrane thickness, pore constrictions (i.e., the narrowest bottlenecks along pore pathways), and lipid surfactants, which are largely similar between leaf and stem xylem and between temperate and tropical trees. However, our mechanistic understanding of embolism propagation and the functional relevance of Tpm,max/Dpm remains elusive.

ano.nymous@ccsd.cnrs.fr.invalid (Sébastien Levionnois) 22 Aug 2024

https://hal.inrae.fr/hal-03681553v1

[hal-03888147] No matter how much space and light are available, radial growth distribution in Fagus sylvatica L. trees is under strong biomechanical control

Key message This study presents the first attempt to quantify how the thigmomorphogenetic syndrome is involved in Fagus sylvatica L. tree growth responses to thinning. An experimental design preventing mechanosensing in half of the trees demonstrated that radial growth distribution in roots and along the tree stem is under strong biomechanical control. Context Studies on the mechanosensitive control of growth under real forest conditions are rare and those existing to date all deal with conifer species. In the current context of global changes, it is important to disentangle how different biotic and abiotic factors affect tree growth. Aims Whereas growth changes after thinning are usually interpreted as responses to decreased competition for resources, this study investigates the importance of how mechanosensing controls growth distribution inside the tree. Methods In an even-aged beech stand, 40 pole-sized trees (size class at first thinning) were selected, half of the plot was thinned and, within each sub-plot (thinned and unthinned), half of the tree were guy-wired in order to remove mechanical stimulations to the lower part of the stem. Four years later, all trees were felled and volume increment, ring width distribution along the tree height, and the largest ring width of the structural roots were measured. The effect of mechanical stimulation in the two treatments (thinned and unthinned) was assessed. Results Removal of mechanical stimulation decreased the volume increment in the lower part of the stem as well as radial root growth but did not affect axial growth. When mechanical strain was removed, the ring width distribution along the stem height changed drastically to an ice-cream cone-like distribution, indicating a strong mechanosensitive control of tree shape. Conclusion In a forest stand, the growth allocation inside the tree is under strong mechanical control. Mechanical stimulations explain more than 50% of the increment stimulated by thinning, whatever the growth indicator. A further challenge is to better understand how cambial cells perceive strains during growth in order to integrate mechanosensing into process-based tree-growth modeling.

ano.nymous@ccsd.cnrs.fr.invalid (Joel Hans Dongmo Keumo Jiazet) 07 Dec 2022

https://agroparistech.hal.science/hal-03888147v1

[hal-03665846] Past and future radial growth and water-use efficiency of Fagus sylvatica and Quercus robur in a long-term climate refugium

The low-latitudinal range margins of many temperate and boreal tree species consist of scattered populations that persist locally in climate refugia. Recent studies have shown that such populations can be remarkably resilient, yet their past resilience does not imply that they are immune to threats from future climate change. The functioning of refugial tree populations therefore needs to be better understood if we are to anticipate their prospects correctly. We performed a detailed study of tree radial growth and vigor in a long-term climate refugial population of beech (Fagus sylvatica), comparing the observed trends with those of co-occurring pedunculate oak (Quercus robur). Annual growth rates (basal area increment, BAI) for both species were similar to those observed in range-core populations, but natural lifespan was half that in the mountains. The master chronologies spanning 1870-2015 revealed 22% (Fagus) and 20% (Quercus) increases in BAI until the 1980s and a smaller decrease (-6% for Fagus,-9% for Quercus) since then. Stable carbon isotope measurements (delta C-13) revealed no effect of cambial age and an increase in water-use efficiency (iWUE) from 1870-2015 of about 50% for Fagus and 20% for Quercus. The trend continued until 2015 in Fagus, whereas Quercus reached its maximum in the 1980s. A detailed analysis of the relationship between climate and annual growth based on a 118-year meteorological record revealed a major role of water availability in the current and previous year. We used the observed climatic relationships to model future growth trends until 2100 for the IPCC scenarios RCP4.5 and RCP8.5. Most projections revealed no change in current growth rates, suggesting that this climate refugium will be able to provide suitable conditions for the persistence of Fagus and Quercus over the coming decades even under warmer and drier regional climate conditions. Overall, our study provides valuable insight into the precise climatic and biological mechanisms enhancing the persistence of refugial tree populations under ongoing climate change.

ano.nymous@ccsd.cnrs.fr.invalid (Didier Bert) 02 Dec 2022

https://hal.inrae.fr/hal-03665846v1

[hal-04066774] Linking ecological niche models and common garden experiments to predict phenotypic differentiation in stressful environments: Assessing the adaptive value of marginal populations in an alpine plant

Environmental variation within a species' range can create contrasting selective pressures, leading to divergent selection and novel adaptations. The conservation value of populations inhabiting environmentally marginal areas remains in debate and is closely related to the adaptive potential in changing environments. Strong selection caused by stressful conditions may generate novel adaptations, conferring these populations distinct evolutionary potential and high conservation value under climate change. On the other hand, environmentally marginal populations may be genetically depauperate, with little potential for new adaptations to emerge. Here, we explored the use of ecological niche models (ENMs) linked with common garden experiments to predict and test for genetically determined phenotypic differentiation related to contrasting environmental conditions. To do so, we built an ENM for the alpine plant Silene ciliata in central Spain and conducted common garden experiments, assessing flowering phenology changes and differences in leaf cell resistance to extreme temperatures. The suitability patterns and response curves of the ENM led to the predictions that: (1) the environmentally marginal populations experiencing less snowpack and higher minimum temperatures would have delayed flowering to avoid risks of late-spring frosts and (2) those with higher minimum temperatures and greater potential evapotranspiration would show enhanced cell resistance to high temperatures to deal with physiological stress related to desiccation and heat. The common garden experiments revealed the expected genetically based phenotypic differentiation in flowering phenology. In contrast, they did not show the expected differentiation for cell resistance, but these latter experiments had high variance and hence lower statistical power. The results highlight ENMs as useful tools to identify contrasting putative selective pressures across species ranges. Linking ENMs with common garden experiments provides a theoretically justified and practical way to study adaptive processes, including insights regarding the conservation value of populations inhabiting environmentally marginal areas under ongoing climate change.

ano.nymous@ccsd.cnrs.fr.invalid (Javier Morente-López) 12 Apr 2023

https://hal.inrae.fr/hal-04066774v1

[hal-03343133] Drought stress recovery of hydraulic and photochemical processes in Neotropical tree saplings

Climate models predict an increase in the severity and the frequency of droughts. Tropical forests are among the ecosystems that could be highly impacted by these droughts. Here, we explore how hydraulic and photochemical processes respond to drought stress and re-watering. We conducted a pot experiment on saplings of five tree species. Before the onset of drought, we measured a set of hydraulic traits, including minimum leaf conductance, leaf embolism resistance, and turgor loss point. During drought stress, we monitored traits linked to leaf hydraulic functioning (leaf water potential (ψmd) and stomatal conductance (gs)) and traits linked to leaf photochemical functioning (maximum quantum yield of photosystem II (Fv/Fm) and maximum electron transport rate (ETRmax)) at different wilting stages. After re-watering the same traits were measured after 3, 7, and 14 days. Hydraulic trait values decreased faster than photochemical trait values. After re-watering, the values of the four traits recovered at different rates. Fv/Fm recovered very fast close to their initial values only three days after re-watering. This was followed by ETRmax, Ψmd and gs. Finally, we show that species with large stomatal and leaf safety margin and low πtlp are not strongly impacted by drought whereas they have a low recovery on photochemical efficiency. These results demonstrate that πtlp, stomatal and leaf safety margin are a good indicators of plant responses to drought stress and also to recovery for photochemical efficiency.

ano.nymous@ccsd.cnrs.fr.invalid (Olivier Jean Leonce Manzi) 14 Sep 2021

https://hal.inrae.fr/hal-03343133v1

[hal-03740191] Is Diversification a Suitable Option to Reduce Drought-Induced Risk of Forest Dieback? An Economic Approach Focused on Carbon Accounting

Extreme or recurrent drought events are the principal source of stress on forests, impairing their overall health. They result in financial losses for forest owners and ecosystem service losses for society. Most of the forested area in the Grand-Est region, France, is covered by European beech, which is projected to decline in the future due to repeated drought events driven by climate change. Diversification is a management option that can reduce the drought-induced risk of dieback. Two types of diversification were separately and jointly analyzed: a mixture of beech species with oak species and a mixture of different tree diameter classes. Two types of losses were also considered: financial and in terms of carbon storage under different occurrences of drought events derived from climate change scenarios. We combined an individual-based model of forest growth with a forest economic approach (i.e., land expectation value or LEV), which we adapted to the stochastic context by developing a doubly-weighted LEV. The maximization of the LEV made it possible to identify the most effective adaptation strategies in terms of timber revenue and carbon storage by means of three different carbon values (i.e., market value, shadow price, and social cost). The results showed that diversification increases timber returns and reduces the loss in timber volume due to the drought-induced risk of forest dieback. However, diversification negatively affects carbon storage. Integrating the value of carbon storage increases the value of the forest stand, but only a high carbon value has a significant economic impact.

ano.nymous@ccsd.cnrs.fr.invalid (Sandrine Brèteau-Amores) 10 Jan 2024

https://hal.inrae.fr/hal-03740191v1

[hal-03774814] Qualitative sustainability assessment of road verge management in France: An approach from causal diagrams to seize the importance of impact pathways

A road verge, also known as a roadside, is a strip of grass or vegetation, sometimes shrubs and trees, that forms a space on the public property located along a road or highway. They require regular maintenance, one of the most relevant reasons being the safety of road users, which implies for territory planners making decisions about the period of maintenance, frequency, the mowing height, or whether or not remove cut biomass from the roadside among others. As highlighted in previous studies, the maintenance strategy decided on has a range of positive and negative impacts on the ecosystem services provided by road verges. Today, however, there is a lack of a formal and holistic view of how these maintenance practices affect the ecosystem services (ES) provided by the roadside. In order to improve the sustainability management of these areas, this paper proposes to use the concept of causal diagrams from the systems theory and literature analysis. This concept helps to structure and represent the impact of road verge maintenance decisions on ES and their interrelationships through causal networks. Nine interrelated causal diagrams were then developed. These diagrams are the first attempt at a qualitative assessment of the impact of roadside management on ES. This work is the first step towards a formal holistic model to assess the sustainability impacts of road verges and the development of decision-making tools.

ano.nymous@ccsd.cnrs.fr.invalid (Brunelle Marche) 27 May 2025

https://hal.science/hal-03774814v1

[hal-04226892] Wood Formation Modeling – A Research Review and Future Perspectives

Wood formation has received considerable attention across various research fields as a key process to model. Historical and contemporary models of wood formation from various disciplines have encapsulated hypotheses such as the influence of external (e.g., climatic) or internal (e.g., hormonal) factors on the successive stages of wood cell differentiation. This review covers 17 wood formation models from three different disciplines, the earliest from 1968 and the latest from 2020. The described processes, as well as their external and internal drivers and their level of complexity, are discussed. This work is the first systematic cataloging, characterization, and process-focused review of wood formation models. Remaining open questions concerning wood formation processes are identified, and relate to: (1) the extent of hormonal influence on the final tree ring structure; (2) the mechanism underlying the transition from earlywood to latewood in extratropical regions; and (3) the extent to which carbon plays a role as “active” driver or “passive” substrate for growth. We conclude by arguing that wood formation models remain to be fully exploited, with the potential to contribute to studies concerning individual tree carbon sequestration-storage dynamics and regional to global carbon sequestration dynamics in terrestrial vegetation models.

ano.nymous@ccsd.cnrs.fr.invalid (Annemarie H Eckes-Shephard) 03 Oct 2023

https://hal.inrae.fr/hal-04226892v1

[hal-03659201] Mapping tree mortality rate in a tropical moist forest using multi-temporal LiDAR

Background and aims: Several studies have shown an increase in tree mortality in intact tropical forests in recent decades. However, most studies are based on networks of field plots whose representativeness is debated. We examine the potential of repeated Airborne LiDAR Scanning data to map forest structure change over large areas with high spatial resolution and to detect tree mortality patterns at landscape level. Methods: The study site is a complex forested landscape in French Guiana with varied topographic positions, vegetation structures and disturbance history. We computed a Gap Dynamics Index from Canopy Height Models derived from successive LiDAR data sets (2009, 2015 and 2019) that we compared to field-measured mortality rates (in stem number and basal area loss) obtained from regular monitoring of 74 1.56-ha permanent plots. Results: At the plot level, the relation between gap dynamics and absolute basal area loss rate (combining fallen and standing dead trees) was overall highly significant (R 2 = 0.60) and especially tight for the 59 ha of unlogged forest (R 2 = 0.72). Basal area loss rate was better predicted from gap dynamics than stem loss rate. In particular, in previously logged plots, intense self-thinning of small stems did not translate into detectable gaps, leading to poor predictability of stem mortality by LiDAR in those forests severely disturbed 30 years before. At the landscape scale, LiDAR data revealed spatial patterns of gap creation that persisted over the successive analysis periods. Those spatial patterns were related to local topography and canopy height. High canopy forests and bottomlands were more dynamic, with a higher fraction of canopy affected by gaps per unit time indicating higher basal area loss rates. Conclusion: Gap detection and mapping via multitemporal LiDAR data is poised to become instrumental in characterizing landscape-scale forest response to current global change. Meaningful comparison of gap dynamics across time and space will, however, depend on consistent LiDAR acquisitions characteristics.

ano.nymous@ccsd.cnrs.fr.invalid (Claudia Huertas) 04 May 2022

https://hal.inrae.fr/hal-03659201v1

[hal-03721086] Water table depth modulates productivity and biomass across Amazonian forests

Aim: Water availability is the major driver of tropical forest structure and dynamics. Most research has focused on the impacts of climatic water availability, whereas remarkably little is known about the influence of water table depth and excess soil water on forest processes. Nevertheless, given that plants take up water from the soil, the impacts of climatic water supply on plants are likely to be modulated by soil water conditions. Location: Lowland Amazonian forests. Time period: 1971–2019. Methods: We used 344 long-term inventory plots distributed across Amazonia to analyse the effects of long-term climatic and edaphic water supply on forest functioning. We modelled forest structure and dynamics as a function of climatic, soil-water and edaphic properties. Results: Water supplied by both precipitation and groundwater affects forest structure and dynamics, but in different ways. Forests with a shallow water table (depth &lt;5 m) had 18% less above-ground woody productivity and 23% less biomass stock than forests with a deep water table. Forests in drier climates (maximum cumulative water deficit &lt; −160 mm) had 21% less productivity and 24% less biomass than those in wetter climates. Productivity was affected by the interaction between climatic water deficit and water table depth. On average, in drier climates the forests with a shallow water table had lower productivity than those with a deep water table, with this difference decreasing within wet climates, where lower productivity was confined to a very shallow water table. Main conclusions: We show that the two extremes of water availability (excess and deficit) both reduce productivity in Amazon upland (terra-firme) forests. Biomass and productivity across Amazonia respond not simply to regional climate, but rather to its interaction with water table conditions, exhibiting high local differentiation. Our study disentangles the relative contribution of those factors, helping to improve understanding of the functioning of tropical ecosystems and how they are likely to respond to climate change.

ano.nymous@ccsd.cnrs.fr.invalid (Thaiane Sousa) 17 Aug 2024

https://hal.inrae.fr/hal-03721086v1

[hal-03807910] Co-limitation towards lower latitudes shapes global forest diversity gradients

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers.

ano.nymous@ccsd.cnrs.fr.invalid (Jingjing Liang) 06 Jul 2023

https://hal.inrae.fr/hal-03807910v1

[hal-03772046] Seasonal variation of leaf thickness: An overlooked component of functional trait variability

The dry and wet seasons in the Neotropics have strong effects on soil water and nutrient availability, as well as on forest dynamics. Despite these major effects on forest ecology, little is known on how leaf traits vary throughout the seasons in tropical rainforest trees. • Here, we investigated the influence of seasonal variations in climate and soil characteristics on leaf trait variation in two tropical tree species. We measured two leaf traits, thickness and water mass per area, in 401 individuals of two species of Symphonia (Clusiaceae) in the Paracou research station in French Guiana tropical lowland rainforest. • We found a significant effect of seasonal variation on these two leaf traits. Soil relative extractable water was a strong environmental predictor of leaf trait variation in response to seasonal variation. Reduced soil water availability during the dry season was associated with increased leaf thickness and water mass per area, possibly as a result of stomatal closure. • Our findings advocate the need to account for environmental seasonality when studying leaf traits in seasonal ecosystems such as tropical forests.

ano.nymous@ccsd.cnrs.fr.invalid (S. Schmitt) 18 Sep 2024

https://hal.inrae.fr/hal-03772046v1

[hal-03694879] Climate change-induced background tree mortality is exacerbated towards the warm limits of the species ranges

Key message : An influence of the recent changes in temperature or rainfall was demonstrated, increasing background tree mortality rates for 2/3 of the 12 studied tree species. Climate change-induced tree mortality was exacerbated towards the warm or dry limits of the species ranges, suggesting in these areas a progressive replacement by more xeric species. Context : Despite the identification of climate change effects on tree mortality in various biomes, the characterization of species-specific areas of vulnerability remains poorly understood. Aims : We sought to assess if the effects of temperature and rainfall changes on background tree mortality rates, which did not result from abrupt disturbances, were linked to climate change intensity only, or if they also depended on the tree’s location along climatic gradients. Methods : We modelled background mortality for 12 of the most common European tree species using 265,056 trees including 4384 dead trees from the French national forest inventory. To explain mortality, we considered variables linked to tree characteristics, stand attributes, logging intensity and site environmental characteristics, and climate change effects. Results : We found an influence of temperature and rainfall changes on 9 species out of 12. For 8 of them, climate change-induced tree mortality was exacerbated towards the warm or dry limits of the species ranges. Conclusion ; These results highlight that tree mortality varies according to the climate change intensity and the tree location along temperature and rainfall gradients. They strengthen the poleward and upward shifts of trees forecasted from climate envelope models for a large number of European tree species.

ano.nymous@ccsd.cnrs.fr.invalid (Adrien Taccoen) 30 Aug 2023

https://hal.science/hal-03694879v1

[hal-03858826] Potential soil methane oxidation in naturally regenerated oak-dominated temperate deciduous forest stands responds to soil water status regardless of their age—an intact core incubation study

Key message: Potential CH 4 oxidation in the top soil layer increased with decreasing soil water content in spring but was inhibited during severe summer drought in naturally-regenerated oak-dominated temperate deciduous forest stands regardless of their age. No direct effect of mineral nitrogen on soil CH 4 oxidation was found. Soil CH 4 oxidation in temperate forests could be reduced by extreme climatic events. Context: The oxidation of atmospheric methane (CH 4) by methanotrophic bacteria in forest soils is an important but overlooked ecosystem service. Aim: Our objective was to determine which factors drive variations in soil CH 4 oxidation in oak-dominated temperate deciduous forest stands of different ages. Methods: Soil samples were collected in 16 stands aged 20 to 143 years in periods of high and low soil water content (SWC). The potential rate of soil CH 4 oxidation was measured by incubating the first five centimetres of intact soil cores at 20 °C. Results: SWC was the main driver accounting for variations in CH 4 oxidation. In spring, a twofold reduction in SWC greatly increased CH 4 oxidation. But when the soil was dry in late summer, a further reduction in SWC led to a decrease in CH 4 oxidation in the top soil layer. No direct effect of mineral nitrogen on soil CH 4 oxidation was found. Conclusions: With regard to soil CH 4 oxidation, naturally regenerated forest stands contribute equally to climate change mitigation regardless of their age. Considering future climate scenarios for Europe, soil CH 4 sink in temperate forests could be reduced, due to both an increase in the number of flooding episodes in spring and drier summers.

ano.nymous@ccsd.cnrs.fr.invalid (Nicolas Bras) 17 Nov 2022

https://hal.univ-lorraine.fr/hal-03858826v1

[hal-04453135] Drought affects the fate of non-structural carbohydrates in hinoki cypress

Tree species that close stomata early in response to drought are likely to suffer from an imbalance between limited carbohydrate supply due to reduced photosynthesis and metabolic demand. Our objective was to clarify the dynamic responses of non-structural carbohydrates to drought in a water-saving species, the hinoki cypress (Chamaecyparis obtusa Sieb. et Zucc.). To this end, we pulse-labeled young trees with 13CO2 10 days after the beginning of the drought treatment. Trees were harvested 7 days later, early during drought progression, and 86 days later when they had suffered from a long and severe drought. The labeled carbon (C) was traced in phloem extract, in the organic matter and starch of all the organs, and in the soluble sugars (sucrose, glucose and fructose) of the most metabolically active organs (foliage, green branches and fine roots). No drought-related changes in labeled C partitioning between belowground and aboveground organs were observed. The C allocation between non-structural carbohydrates was altered early during drought progression: starch concentration was lower by half in the photosynthetic organs, while the concentration of almost all soluble sugars tended to increase. The preferential allocation of labeled C to glucose and fructose reflected an increased demand for soluble sugars for osmotic adjustment. After 3 months of a lethal drought, the concentrations of soluble sugars and starch were admittedly lower in drought-stressed trees than in the controls, but the pool of non-structural carbohydrates was far from completely depleted. However, the allocation to storage had been impaired by drought; photosynthesis and the sugar translocation rate had also been reduced by drought. Failure to maintain cell turgor through osmoregulation and to refill embolized xylem due to the depletion in soluble sugars in the roots could have resulted in tree mortality in hinoki cypress, though the total pool of carbohydrate was not completely depleted.

ano.nymous@ccsd.cnrs.fr.invalid (Chiaki Tsuji) 12 Feb 2024

https://hal.science/hal-04453135v1

[hal-04327133] Variability in Stem Methane Emissions and Wood Methane Production of Different Tree Species in a Cold Temperate Mountain Forest

The role of trees, in addition to that of the soil, must be considered in CH4 budget for forests. Although trees can emit CH4 through their stems, there are uncertainties about the main factors that explain inter- and intraspecific variations, which impedes upscaling of measurements from the stem to the ecosystem level. This study aimed to characterize the variability in CH4 emissions (F-CH4) from stems between species and individuals, and within individuals. We measured F-CH4 in situ during the snow-free period in five species in a temperate mountain forest, using individuals of different sizes and chambers at different heights along the stems. One coniferous species emitted almost no CH4, whereas four broadleaved species exhibited high intraspecific variability in F-CH4 (0-3.7 nmol m(-2) s(-1)). Increasing trends in F-CH4 with tree diameter were observed for four species. The vertical patterns in F-CH4 were complex. Seasonal variations in F-CH4, measured on two trees per species, were well explained by air temperature with apparent temperature sensitivity coefficients (Q(10)) between 1.2 and 2, which were not related to the antecedent precipitation indices, whether calculated over 7 or 30 days. Potential CH4 production was detected in wood core segments incubated under anoxic conditions in the majority of individual trees of all species. Our results suggest that the CH4 emitted by trunks can originate either from soil or internal sources. Scaling F-CH4 from trees at the stand level and developing process-based models of F-CH4 will remain challenging until the sources of variation are better explained.

ano.nymous@ccsd.cnrs.fr.invalid (Daniel Epron) 06 Dec 2023

https://hal.inrae.fr/hal-04327133v1

[hal-03442289] Ant Colony Optimization for Estimating Pith Position on Images of Tree Log Ends

The pith location is one of the most important features to detect in order to determine the quality of wood. Indeed, it allows to extract other important features. In this paper, we address the problem of pith detection on images of wood cross-sections. Taking such images can be done at little cost and with a high resolution. However, contrary to computed tomographic images, digital images exhibit disturbances like sawing marks, dirt or ambient light variations which make difficult the image analysis. Few studies have focused on such images. Furthermore these studies do some prior segmentation or cropping before the detection. We propose an approach for estimating the pith location without any requirements. Our method is based on an ant colony optimization algorithm. It is a probabilistic approach for solving this task. We validate our algorithm on images of Douglas fir captured after harvesting. The efficiency of this algorithm has been demonstrated by performance comparisons with other approaches. Experiments show an accurate and fast estimation and the algorithm could be used in real time, at sawmill environment or in forest, with a smartphone.

ano.nymous@ccsd.cnrs.fr.invalid (Rémi Decelle) 26 Aug 2024

https://hal.science/hal-03442289v1

[hal-04126514] AquaDesign: A tool to assist aquaculture production design based on abiotic requirements of animal species

Farming new species and promoting polyculture can enhance aquaculture sustainability. This implies to define the rearing conditions that meet the ecological requirements of a target species and/or to assess if different species can live in the same farming environment. However, there is a large number of rearing conditions and/or taxon combinations that can be considered. In order to minimise cumbersome and expensive empirical trials to explore all possibilities, we introduce a tool, AquaDesign. It is based on a R-script and package which help to determine farming conditions that are most likely suitable for species through in silico assessment. We estimate farming conditions potentially suitable for an aquatic organism by considering the species niche. We define the species n-dimensional niche hypervolume using a correlative approach in which the species niche is estimated by relating distribution data to environmental conditions. Required input datasets are mined from several public databases. The assistant tool allows users to highlight (i) abiotic conditions that are most likely suitable for species and (ii) combinations of species potentially able to live in the same abiotic environment. Moreover, it offers the possibility to assess if a particular set of abiotic conditions or a given farming location is potentially suitable for the monoculture or the polyculture of species of interest. Our tool provides useful pieces of information to develop freshwater aquacultures. Using the large amount of biogeographic and abiotic information available in public databases allows us to propose a pragmatic and operational tool even for species for which abiotic requirements are poorly or not available in literature such as currently non-produced species. Overall, we argue that the assistant tool can act as a stepping stone to promote new aquatic productions which are required to enhance aquaculture sustainability.

ano.nymous@ccsd.cnrs.fr.invalid (Grégoire Butruille) 13 Jun 2023

https://hal.science/hal-04126514v1

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Productions 2022

HAL : Dernières publications

[hal-05240498] Quantitative expression of mesophyll conductance temperature response in the FvCB model and impacts on plant gas exchange estimations

[hal-03714709] A standardized morpho-functional classification of the planet's humipedons

[hal-03981724] The response of mesophyll conductance to ozone-induced oxidative stress is genotype-dependent in poplar

[hal-03873631] High exposure of global tree diversity to human pressure

[hal-03639012] Climate and ungulate browsing impair regeneration dynamics in spruce-fir-beech forests in the French Alps

[hal-03638143] Historical landscape matters for threatened species in French mountain forests

[hal-03518443] Global maps of soil temperature

[hal-03846703] Stronger legacy effects of cropland than of meadows or pastures on soil conditions and plant communities in French mountain forests

[hal-03502713] Uncovering the critical soil moisture thresholds of plant water stress for European ecosystems

[hal-04895169] Bark composition changes along the trunk of three softwood species: Picea abies , Abies alba Mill. and Pseudotsuga menziesii

[hal-03757303] Comparative Copper Resistance Strategies of Rhodonia placenta and Phanerochaete chrysosporium in a Copper/Azole-Treated Wood Microcosm

[hal-03863446] Genotypic and tissue-specific variation of Populus nigra transcriptome profiles in response to drought

[hal-03880254] The 2018 European heatwave led to stem dehydration but not to consistent growth reductions in forests

[hal-03518448] Tropical and subtropical Asia's valued tree species under threat

[hal-04033784] Plant invasion modifies isohydricity in Mediterranean tree species

[hal-03619993] Embedding non-industrial private forest owners in forest policy and bioeconomy issues using a Living Lab concept

[hal-03468938] CNN-based Method for Segmenting Tree Surface Singularites

[hal-04327109] A review of the heterogeneous landscape of biodiversity databases: opportunities and challenges for a synthesized biodiversity knowledge base

[hal-05167356] Réseau ESPERENSE : une évaluation participative des essences de demain

[hal-03926055] With increasing site quality asymmetric competition and mortality reduces Scots pine (Pinus sylvestris L.) stand structuring across Europe

[hal-03519397] Do trait responses to simulated browsing in Quercus robur saplings affect their attractiveness to Capreolus capreolus the following year?

[hal-03829175] PSDR4 ASTRAL - Acteurs et Services écosystémiques des Territoires RurAux Lorrains

[hal-03919731] Dendrometric data from the silvicultural scenarios developed by Office National des Forêts (ONF) in France: a tool for applied research and carbon storage estimates

[hal-03926054] Identification and spatial extent of understory plant species requiring vegetation control to ensure tree regeneration in French forests

[hal-03926053] The distribution of carbon stocks between tree woody biomass and soil differs between Scots pine and broadleaved species (beech, oak) in European forests

[hal-03654545] Estimating natural background concentrations for dissolved constituents in groundwater: A methodological review and case studies for geogenic fluoride

[hal-03643415] A limited number of species is sufficient to assign a vegetation plot to a forest vegetation unit

[hal-03860136] Plant root growth against a mechanical obstacle: the early growth response of a maize root facing an axial resistance is consistent with the Lockhart model

[hal-03658479] Traceability and quality assessment of Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) logs: the TreeTrace_Douglas database

[hal-03736228] Non-structural carbohydrates and morphological traits of leaves, stems and roots from tree species in different climates

[hal-03952012] Leaf and tree water-use efficiencies of Populus deltoides × P. nigra in mixed forest and agroforestry plantations

[hal-04019710] Provenance Differences in Water-Use Efficiency Among Sessile Oak Populations Grown in a Mesic Common Garden

[hal-03681553] Pit Characters Determine Drought-Induced Embolism Resistance of Leaf Xylem across 18 Neotropical Tree Species

[hal-03888147] No matter how much space and light are available, radial growth distribution in Fagus sylvatica L. trees is under strong biomechanical control

[hal-03665846] Past and future radial growth and water-use efficiency of Fagus sylvatica and Quercus robur in a long-term climate refugium

[hal-04066774] Linking ecological niche models and common garden experiments to predict phenotypic differentiation in stressful environments: Assessing the adaptive value of marginal populations in an alpine plant

[hal-03343133] Drought stress recovery of hydraulic and photochemical processes in Neotropical tree saplings

[hal-03740191] Is Diversification a Suitable Option to Reduce Drought-Induced Risk of Forest Dieback? An Economic Approach Focused on Carbon Accounting

[hal-03774814] Qualitative sustainability assessment of road verge management in France: An approach from causal diagrams to seize the importance of impact pathways

[hal-04226892] Wood Formation Modeling – A Research Review and Future Perspectives

[hal-03659201] Mapping tree mortality rate in a tropical moist forest using multi-temporal LiDAR

[hal-03721086] Water table depth modulates productivity and biomass across Amazonian forests

[hal-03807910] Co-limitation towards lower latitudes shapes global forest diversity gradients

[hal-03772046] Seasonal variation of leaf thickness: An overlooked component of functional trait variability

[hal-03694879] Climate change-induced background tree mortality is exacerbated towards the warm limits of the species ranges

[hal-03858826] Potential soil methane oxidation in naturally regenerated oak-dominated temperate deciduous forest stands responds to soil water status regardless of their age—an intact core incubation study

[hal-04453135] Drought affects the fate of non-structural carbohydrates in hinoki cypress

[hal-04327133] Variability in Stem Methane Emissions and Wood Methane Production of Different Tree Species in a Cold Temperate Mountain Forest

[hal-03442289] Ant Colony Optimization for Estimating Pith Position on Images of Tree Log Ends

[hal-04126514] AquaDesign: A tool to assist aquaculture production design based on abiotic requirements of animal species