Lockdown during COVID-19 pandemic: impact on road traffic noise and on the perception of sound environment in France

Acoucité¹, centre of expertise in environmental acoustics and observatory of the sound environment, has investigated the changes in sound environment and its perception during the French lockdown period. The approach adopted is multidimensional, since it combines long-term acoustic measurements, large area noise mapping, as well as the study of sound perception self-reported by population sample through an on-line structured questionnaire. Data from 21 continuous sound monitoring stations² were analysed for the entire lockdown period in five conurbations in the south of France and compared to typical values in the “normal” situation (before lockdown) in order to quantify the reduction in terms of sound levels. Reductions from 4 dB to 6 dB (Lden) were observed for monitoring stations with highly dominant road noise. These results were used to obtain new Strategic Noise Maps for road noise (corresponding to the lockdown situation) for the conurbations of Lyon and Grenoble. The impact of such reductions in terms of noise exposure of their inhabitants was thus assessed. An estimation of the impact on health effects in comparison with the “normal” situation (Strategic Noise Maps “Round 3 CE-DE-2002”) was also carried out. This estimation considers a scenario where the above level reductions (4 to 6 dB) would take place in the long-term. An on-line perception questionnaire was available during the lockdown period with the aim of gathering information on the way that the changes in sound environment were perceived by people all over France and ended up with more than 3000 respondents. This paper reports the main findings of the study in terms of acoustics and sound perception

Soil water stress affects both cuticular wax content and cuticle-related gene expression in young saplings of maritime pine (Pinus pinaster Ait)

Background: The cuticle is a hydrophobic barrier located at the aerial surface of all terrestrial plants. Recent studies performed on model plants, such as Arabidopsis thaliana, have suggested that the cuticle may be involved in drought stress adaptation, preventing non-stomatal water loss. Although forest trees will face more intense drought stresses (in duration and intensity) with global warming, very few studies on the role of the cuticle in drought stress adaptation in these long-lived organisms have been so far reported. Results: This aspect was investigated in a conifer, maritime pine (Pinus pinaster Ait.), in a factorial design with two genetic units (two half-sib families with different growth rates) and two treatments (irrigated vs non-irrigated), in field conditions. Saplings were grown in an open-sided greenhouse and half were irrigated three times per week for two growing seasons. Needles were sampled three times per year for cuticular wax (composition and content) and transcriptome (of 11 genes involved in cuticle biosynthesis) analysis. Non-irrigated saplings (i) had a higher cuticular wax content than irrigated saplings and (ii) overexpressed most of the genes studied. Both these trends were more marked in the faster growing family. Conclusions: The higher cuticular wax content observed in the non-irrigated treatment associated with strong modifications in products from the decarbonylation pathway suggest that cuticular wax may be involved in drought stress adaptation in maritime pine. This study provides also a set of promising candidate genes for future forward genetic studies in conifers

Effets de la fertilisation et de l’irrigation sur le statut P du sol et les activités phosphatases

National audienc

Fine root density, branching pattern and mycorrhizal diversity across Pinus pinaster stands in south west France: methodology and first results

International audienc

P availability, fine root properties and functional mycorrhizal diversity across Pinus pinaster stands with different productivity in South-western France

National audienc

Spring and autumnal P availability, fine root properties and functional mycorrhizal diversity across Pinus pinaster stands with different productivity in southwest France

International audienc

Grain carbon isotope composition is a marker for allocation and harvest index in wheat

The natural C-13 abundance (delta C-13) in plant leaves has been used for decades with great success in agronomy to monitor water-use efficiency and select modern cultivars adapted to dry conditions. However, in wheat, it is also important to find genotypes with high carbon allocation to spikes and grains, and thus with a high harvest index (HI) and/or low carbon losses via respiration. Finding isotope-based markers of carbon partitioning to grains would be extremely useful since isotope analyses are inexpensive and can be performed routinely at high throughput. Here, we took the advantage of a set of field trials made of more than 600 plots with several wheat cultivars and measured agronomic parameters as well as delta C-13 values in leaves and grains. We find a linear relationship between the apparent isotope discrimination between leaves and grain (denoted as Delta delta(corr)), and the respiration use efficiency-to-HI ratio. It means that overall, efficient carbon allocation to grains is associated with a small isotopic difference between leaves and grains. This effect is explained by postphotosynthetic isotope fractionations, and we show that this can be modelled by equations describing the carbon isotope composition in grains along the wheat growth cycle. Our results show that C-13 natural abundance in grains could be useful to find genotypes with better carbon allocation properties and assist current wheat breeding technologies

Grain carbon isotope composition is a marker for allocation and harvest index in wheat

International audienceThe natural C-13 abundance (delta C-13) in plant leaves has been used for decades with great success in agronomy to monitor water-use efficiency and select modern cultivars adapted to dry conditions. However, in wheat, it is also important to find genotypes with high carbon allocation to spikes and grains, and thus with a high harvest index (HI) and/or low carbon losses via respiration. Finding isotope-based markers of carbon partitioning to grains would be extremely useful since isotope analyses are inexpensive and can be performed routinely at high throughput. Here, we took the advantage of a set of field trials made of more than 600 plots with several wheat cultivars and measured agronomic parameters as well as delta C-13 values in leaves and grains. We find a linear relationship between the apparent isotope discrimination between leaves and grain (denoted as Delta delta(corr)), and the respiration use efficiency-to-HI ratio. It means that overall, efficient carbon allocation to grains is associated with a small isotopic difference between leaves and grains. This effect is explained by postphotosynthetic isotope fractionations, and we show that this can be modelled by equations describing the carbon isotope composition in grains along the wheat growth cycle. Our results show that C-13 natural abundance in grains could be useful to find genotypes with better carbon allocation properties and assist current wheat breeding technologies

Association between transportation noise exposure and type 2diabetes risk in the French E3N cohort

International audienc

Association entre l'exposition au bruit et le risque de maladies cardio-métaboliques (diabète de type 2, hypertension artérielle ou maladie cardio-vasculaire)

Introduction : L’exposition au bruit semble être associée à un risque de développer une maladie cardio-métabolique (MCM) : hypertension artérielle (HTA), diabète de type 2 (DT2) ou infarctus du myocarde. Cependant, il existe peu d’études en France qui explorent cette association, et celles considérant les marqueurs de risque cardio-métaboliques (comme la tension artérielle, la glycémie ou le rythme cardiaque) sont peu nombreuses à l’étranger et inexistantes en France. C’est la raison pour laquelle le projet BROUHAHA a été mis en place. Objectifs : Le volet A de BROUHAHA vise à évaluer l’association entre l’exposition au bruit et le risque de développer une MCM. Le volet B a pour objectif d’évaluer l’association entre l’exposition au bruit à court terme et les variations des marqueurs cardio-métaboliques. Méthodes : Volet A : Dans une sous-cohorte de 22 000 femmes de la cohorte E3N (Étude Épidémiologique auprès de femmes de l'Éducation Nationale), l’estimation de l’exposition au bruit sera calculée à partir des cartes stratégiques de bruit au domicile de chaque femme ayant résidé en Île-de-France (IdF) ou en Auvergne Rhône-Alpes (AuRa) entre 2000 et 2018, puis mise en relation avec le risque de développer une MCM. Volet B : Une étude pilote sera menée auprès de 120 hommes et femmes de la cohorte E4N-G2 (enfants des femmes E3N), en bonne santé, habitant en IdF ou en AuRA. L’exposition au bruit sera évaluée pendant 7 jours à l’aide d’un dosimètre et de l’application NoiseCapture. Les marqueurs cardio-métaboliques (activité physique, sommeil, rythme cardiaque, tension artérielle et glycémie) seront mesurés avec un bracelet, un tensiomètre et un capteur de glycémie connectés. Le contexte dans lequel s’inscrit ce projet BROUHAHA ainsi que le protocole de ces deux volets seront présentés