HAL Portal AgroParisTech
Not a member yet
73916 research outputs found
Sort by
Les radios locales peuvent-elles contribuer à la surveillance épidémiologique ?
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616762/) * Autres projets (id;sigle;titre): ;TSARA;(FRA) Transformer les systèmes alimentaires et l'agriculture par la recherche en partenariat avec l'Afrique//International audienc
Quantifying the impact of co-registration and satellite jitter filtering on the accuracy of multi-temporal elevation differences
No full textInternational audienceMulti-temporal satellite-based change detection analysis requires addressing biases related to coregistration and satellite jitter. This study compares two workflows combining two co-registration strategies with jitter filtering using Pléiades imagery from 2015 and 2023. The Time-SIFT approach shows improved horizontal accuracy and comparable vertical accuracy compared to the classical approach without requiring GCPs or pre-georeferenced data, reducing elevation difference dispersion from 1.71 to 1.32 m in terms of NMAD. After jitter correction, dispersions reach 1.13 m and 0.96 m NMAD for the classical and the Time-SIFT approaches, respectively. These results demonstrate that the Time-SIFT co-registration quality yields improved elevation difference after filtering
Combined “omics” and physiological approaches highlight the roles of the GABA shunt and mitochondria-related functions in rice seed longevity
No full textInternational audienceIn the context of global warming, the ability of seeds to withstand higher temperatures and humidity during dry storage is critical to maintain food production. Seed longevity, also referred to as storability, is therefore an essential trait. As a major staple crop, rice (Oryza sativa L.) has been widely studied to identify the genetic determinants of seed longevity, primarily through QTL mapping and molecular analyses. However, integrated multi-omics data remain limited, especially compared to advances made for other seed physiological features (e.g., dry quiescence, germination). This study investigates the molecular determinants of rice seed longevity under varying storage conditions using controlled deterioration treatments (CDTs) at 25 °C (no deterioration), 40 °C (reduction of germination speed and uniformity) and 45 °C (loss of germinative capacity) under high relative humidity. Through physiological characterizationand multi-omics analyses, we identified key metabolic pathways and genetic factors associated with seed aging. By integrating transcriptomic, proteomic, and metabolomic data, we pinpointed specific pathways critical to seed viability loss. CDTs revealed that only a small number of genes and proteins are significantly affected. In particular, our results highlight a major impact of CDTs on the GABA shunt and mitochondrial factors as the DEAD-box ATP-dependent RNA helicase 9. Altogether, this work opens the way for in-depth functional studies on a small number of mitochondria-related genes involved in rice seed longevity
The Territorial Circular Ecosystem: Foundations for a Systemic and Place-Based Approach to Circular Economy
No full textInternational audienceThis article introduces the concept of the Territorial Circular Ecosystem (TCE) as a framework to understand the conditions that support the deployment of circular economy principles at the local level. It draws on the legacy of local production systems, from Marshallian districts to more recent approaches such as green clusters and industrial symbioses. These models have contributed to the ecological transition of economic systems but continue to show important limitations regarding for example the coordination of actors, the integration of stakeholders, and the implementation of circular strategies based on the 10R. The TCE framework defines a set of components and relational mechanisms rooted in territorial dynamics. It places emphasis on various types of local cooperation, geographical and organized proximities, institutional support, and societal involvement. This contribution establishes a conceptual foundation for the analysis of local circular systems and provides useful orientations for public policy and future empirical research
From organo-mineral interactions to soil and carbon policies: bridging science and policy for soil health and climate action
No full textInternational audienceSoil organic carbon (SOC) plays a central role in climate mitigation, ecosystem functioning, and soil health. Its prominence in recent European and international policy frameworks, such as the European Climate Law, the Soil Monitoring and Resilience Directive and the Carbon Removal Certification Framework, has created new demands for actionable, policy-relevant science. This paper reviews how advances in the understanding of organo-mineral associations can inform soil carbon policies, with a particular focus on the estimation of C sequestration potential in soils and the design of meaningful soil health indicators. It examines different approaches to estimate SOCstorage potentials, including carbon saturation concepts and data-driven pedoclimatic benchmarking, and discusses the strengths and limitations of proposed indicators such as the SOC/clay ratio. The importance of terminology consistency, methodology harmonization, and stratification of results per pedoclimatic context is highlighted throughout. We argue for tiered and contextsensitive approaches to support robust, fair, and operational frameworks for soil monitoring and carbon accounting. By aligning scientific tools with the diversity of European landscapes and policy objectives, we can ensure that the rich and evolving understanding of organo-mineral interactionscontinues to shape credible, effective, and fair soil and carbon policies
Decreasing frequency and extent of frost damage in European oaks over 1961-2021
No full textInternational audienceLate spring frosts (LSF) have substantial ecological and economic impacts in the temperate and boreal zones. Yet, the effects of climate warming on the frequency (i.e., probability of LSF in a given year, in %) and extent (i.e., percentage of trees in a population damaged by a given LSF event) of LSF damage remain underexplored. Here, extending a budburst model that accounts for within-population variability, we developed and evaluated a new model of LSF damage occurrence and extent using 1,220 observations of LSF damage to newly emerged leaves from 304 oak populations in France (1997-2021). Our model simulations reveal that overall, French oak populations are, over time, less exposed to LSF amid ongoing climate change. We observed an overall decline in the frequency (-0.22 % per year) and extent (-0.34 % per year) of LSF damage in French oak populations over the past six decades (1961-2021). These trends are largely driven by the temporal advance of both the last spring frost day and budburst dates, with the last spring frost day advancing at a slightly faster rate (-0.28 days per year) than budburst (-0.21 days per year). This temporal mismatch explains why, contrary to the common assumption that earlier budburst increases frost risk, earlier budburst was in fact associated with a lower frequency of LSF damage. Nevertheless, considerable geographical variability emerged, with declines in damage frequency being more pronounced in continental regions, whereas declines in damage extent were more pronounced in coastal regions. Our findings underscore the importance of considering both LSF frequency and extent when assessing frost risks in a warming climate, offering a comprehensive framework for future ecological and economic evaluations of LSF impacts.</div
Comparison of soil property predictions in Lithuanian croplands using UAV, satellite, EMI data and machine learning
No full textInternational audienceCombining remote and proximal sensing provides a cost-effective solution for mapping soil properties in croplands. This study assessed the potential of remote sensing based on high resolution multispectral UAV imagery (2.6 cm), satellite (Sentinel-2), and in-field measured electromagnetic induction (EMI) data for predicting six soil properties − soil organic carbon content (SOC), clay, sand, silt contents, pH, and soil water content (SWC) − across five Lithuanian agroclimatic zones. Seven modelling scenarios, using individual and combined sources of sensor data, employing a random forest model, were evaluated. To assess real-world applicability, sampling-reduction simulation were additionally performed. SOC and clay predictions achieved the highest accuracy, while silt, sand, and SWC showed acceptable accuracy only in a few sites or specific modelling scenarios. Soil pH predictions were poor across all scenarios. Prediction accuracy varied across study sites, likely influenced by climate, soil parent material, topography, and agricultural management. Sensor data resolutions (2.6 cm, 1.6 m, 10 m per pixel) significantly affected prediction accuracy. For SOC predictions, UAV and Sentinel-2 data performed best, while EMI alone was less effective. In contrast, for clay predictions, EMI data yielded the highest accuracy, emphasizing its role for soil texture assessment. Multi-sensor fusion improved model performance during training but did not consistently enhance validation accuracy across sites, highlighting important cost–accuracy trade-offs and the need for realistic performance evaluation. Overall, the results demonstrate that the benefits of multi-sensor soil mapping are property-specific and site-dependent, providing guidance for scalable and economically viable field-scale soil mapping strategies
Nutrient Enrichment by Poultry Biochar Reshapes Soil Microbial Networks, Reducing Interaction Complexity in Tropical Sandy Soils
No full textInternational audiencePurpose This study evaluated how poultry manure-derived biochar influences the structure, diversity, and co-occurrence networks of soil bacterial communities in nutrient-poor tropical sandy soils. We examined the trade-off between improved soil fertility and potential simplification of microbial networks, testing the hypothesis that high biochar rates would enhance nutrient availability but reduce microbial complexity and diversity. Methods A field experiment was conducted over two years in sandy soils of northeastern Brazil, applying poultry biochar. We used six treatments: (a) control (no amendments), (b) low-rate biochar (Bio_10t = 10 t ha⁻¹), (c) high-rate biochar (Bio_40t = 40 t ha⁻¹), (d) chicken manure (E.Av = 5 t ha⁻¹), (e) synthetic mineral fertilizer (Mineral = NPK), and (f) poultry manure (C.Av = 10 t ha⁻¹). Soil chemical properties were assessed, and bacterial communities were analyzed using 16 S rRNA gene sequencing. Network analyses were performed using SparCC and NetCoMi, and multivariate statistics determined key environmental drivers. Results High biochar inputs increased organic C, P, and K levels, leading to a distinct shift in microbial community structure. However, this nutrient enrichment reduced amplicon sequence variants richness by 22.4% (from 3,250 to 2,521) and Shannon diversity by 3.6% (from 7.16 to 6.90) relative to the control. Network analysis showed substantial simplification of microbial interactions: the control treatment had 3,116 co-occurrence edges, which fell to 1,423 under low biochar (Bio_10t) and 1,849 under high biochar (Bio_40t)—reductions of 54% and 40%, respectively
Real-time fermentation tracking of p-coumaric acid using Waveguide-Enhanced Raman Spectroscopy (WERS): Runing title: Raman monitoring of p-coumaric acid
No full textThe efficient bioproduction of p-coumaric acid (p-CA) in Saccharomyces cerevisiae remains limited by the compound's low solubility and inhibitory effects at elevated concentrations, highlighting the need for real-time process monitoring to support advanced control strategies. This study evaluates the use of waveguide-enhanced Raman spectroscopy (WERS) as an in situ, real-time analytical tool for tracking p-CA fermentation dynamics. A recently developed Raman-on-a-chip sensor successfully quantified key metabolites directly within turbid, complex fermentation media. Chemometric models built from Raman spectra accurately predicted p-CA, ethanol, glycerol, glucose and acetic acid concentrations, with Root Mean Squared Error of Prediction of 0.37 g.L -1 , 2.9 g.L -1 , 1.3 g.L -1 , 6.3 g.L -1 and 0.54 g.L -1 , and corresponding correlation coefficients of 0.63, 0.86, 0.80, 0.43 and 0.87. These performances support reliable monitoring and early detection of metabolic shift. When combined with an optimized semi-defined medium and fed-batch strategy, WERS provided a reproducible monitoring framework that supported improved p-CA production performance, representing a 2.3-fold increase compared to the batch process. Beyond demonstrating analytical feasibility, these results position WERS as a scalable Process Analytical Technology (PAT) suitable for integration into feedback-controlled or continuous extraction systems aimed at mitigating p-CA product inhibition to enhance yield, maintain culture viability, and streamline industrial p-CA biomanufacturing.</div
Vacuum pyrolysis of olive pomace for biochar production: Enhancing carbon stability and soil nutrient supply
No full textInternational audienceOlive pomace (OP), a significant agro-industrial byproduct in Mediterranean countries, poses considerable disposal challenges and offers potential as a feedstock for engineered biochar production. Conventional pyrolysis of OP has been widely studied and often yields biochar with limited aromaticity and variable nutrient content. However, no prior work has explored the potential of vacuum pyrolysis for this residue. Addressing this research gap, this study investigates the use of vacuum pyrolysis (500 °C, 15–20 kPa, 2 h) to transform OP into a stable and nutrient-rich biochar. The process yielded 30.9 wt.% biochar with 68.7 % fixed carbon, representing an improvement of 20 % in carbon retention compared with atmospheric pyrolysis. Elemental ratios (H/C = 0.03 and O/C = 0.18) confirmed high aromaticity and long-term stability, while mineral enrichment underscored high agronomic value. The biochar displayed a cation exchange capacity of 56.2 cmolc/kg and 79 % porosity, properties favorable for nutrient cycling, and soil remediation. The carbon sequestration potential was estimated at 2.6 tCO₂eq per ton of biochar applied and heavy metals were below international thresholds, ensuring environmental safety. Beyond material characterization, the work highlights engineering advantages, including reduced inert gas requirements and a reusable syngas fraction (64.6 wt.%) that can offset energy costs. However, as the study was conducted at a single pressure level, the specific contribution of vacuum conditions requires further confirmation through multi-pressure trials. Such results position vacuum pyrolysis as a promising technology for waste valorization, carbon management, and climate-smart agriculture, while future research should address field validation, contaminant screening, and life-cycle performance