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New (a)biotic conditions resulting from climate change are expected to change disturbance dynamics, such as windthrow, forest fires, droughts, and insect outbreaks, and their interactions. These unprecedented natural disturbance dynamics might alter the capability of forest ecosystems to buffer atmospheric CO2 increases, potentially leading forests to transform from sinks into sources of CO2. This study aims to enhance the ORCHIDEE land surface model to study the impacts of climate change on the dynamics of the bark beetle, Ips typographus, and subsequent effects on forest functioning. The Ips typographus outbreak model is inspired by previous work from Temperli et al. (2013) for the LandClim landscape model. The new implementation of this model in ORCHIDEE r8627 accounts for key differences between ORCHIDEE and LandClim: (1) the coarser spatial resolution of ORCHIDEE; (2) the higher temporal resolution of ORCHIDEE; and (3) the pre-existing process representation of windthrow, drought, and forest structure in ORCHIDEE. Simulation experiments demonstrated the capability of ORCHIDEE to simulate a variety of post-disturbance forest dynamics observed in empirical studies. Through an array of simulation experiments across various climatic conditions and windthrow intensities, the model was tested for its sensitivity to climate, initial disturbance, and selected parameter values. The results of these tests indicated that with a single set of parameters, ORCHIDEE outputs spanned the range of observed dynamics. Additional tests highlighted the substantial impact of incorporating Ips typographus outbreaks on carbon dynamics. Notably, the study revealed that modeling abrupt mortality events as opposed to a continuous mortality framework provides new insights into the short-term carbon sequestration potential of forests under disturbance regimes by showing that the continuous mortality framework tends to overestimate the carbon sink capacity of forests in the 20- to 50-year range in ecosystems under high disturbance pressure compared to scenarios with abrupt mortality events. This model enhancement underscores the critical need to include disturbance dynamics in land surface models to refine predictions of forest carbon dynamics in a changing climate. [ABSTRACT FROM AUTHOR]

Oxygenated organic molecules (OOMs) play an important role in the formation of atmospheric aerosols. Due to various analytical challenges with respect to measuring organic vapors, uncertainties remain regarding the formation and fate of OOMs. The chemical ionization Orbitrap (CI-Orbitrap) mass spectrometer has recently been shown to be a powerful technique that is able to accurately identify gaseous organic compounds due to its greater mass resolution. Here, we present the ammonium-ion-based CI-Orbitrap (NH4+ -Orbitrap) as a technique capable of measuring a wide range of gaseous OOMs. The performance of the NH4+ -Orbitrap is compared with that of state-of-the-art mass spectrometers, including a nitrate-ion-based chemical ionization atmospheric pressure interface coupled to a time-of-flight mass spectrometer (NO3- -LTOF), a new generation of proton transfer reaction-TOF mass spectrometer (PTR3-TOF), and an iodide-based CI-TOF mass spectrometer equipped with a Filter Inlet for Gases and AEROsols (I- -CIMS). The instruments were deployed simultaneously in the Cosmic Leaving OUtdoors Droplets (CLOUD) chamber at the European Organization for Nuclear Research (CERN) during the CLOUD14 campaign in 2019. Products generated from α -pinene ozonolysis under various experimental conditions were simultaneously measured by the mass spectrometers. The NH4+ -Orbitrap was able to identify the widest range of OOMs (i.e., O ≥ 2), from less-oxidized species to highly oxygenated organic molecules (HOMs). Excellent agreement was found between the NH4+ -Orbitrap and the NO3- -LTOF with respect to characterizing HOMs and with the PTR3-TOF for the less-oxidized monomeric species. OOM concentrations measured by NH4+ -Orbitrap were estimated using calibration factors derived from the OOMs with high time-series correlations during the side-by-side measurements. As with the other mass spectrometry techniques used during this campaign, the detection sensitivity of the NH4+ -Orbitrap to OOMs is greatly affected by relative humidity, which may be related to changes in ionization efficiency and/or multiphase chemistry. Overall, this study shows that NH4+ -ion-based chemistry associated with the high mass resolution of the Orbitrap mass analyzer can measure almost all inclusive compounds. As a result, it is now possible to cover the entire range of compounds, which can lead to a better understanding of the oxidation processes. [ABSTRACT FROM AUTHOR]

Mangrove ecosystems provide key ecosystem services in coastal areas. This study describes the riparian mangrove of the Wouri estuary, in the Douala region (Cameroon), emphasizing the changes in this ecosystem over the past decade and its current state. It highlights the different groups of actors who participate in the management and regulation of the resource. Finally, an analysis of the governance of the mangrove wood resource based on the theory of common goods by Elinor Ostrom (1990) is proposed by examining the results obtained from the previous points. The scientific interest lies in contributing to a better understanding of the socio-ecological changes in the mangrove in the context of increasing anthropogenic pressures, highlighting the governance challenges and conservation opportunities in a strategic region of Central Africa. This research reveals complex processes that characterize mangrove ecosystems on the Manoka and Cap Cameroon Islands. The lack of urbanization regulations, continued infrastructure growth, repeated flooding, and coastal erosion all have a negative impact on natural landscapes and forests. The use of wood for smoking and fishing, as well as coastal pollution resulting from deficient garbage management, also have a considerable influence. Strategic interventions are needed to ensure sustainable ecosystem management. Recommendations include the application of rules to prevent forest overexploitation. [ABSTRACT FROM AUTHOR]

Oxygenated organic molecules (OOMs) play an important role in the formation of atmospheric aerosols. Due to various analytical challenges in measuring organic vapors, uncertainties remain in the formation and fate of OOMs. The chemical ionization Orbitrap mass spectrometer (CI-Orbitrap) has recently been shown to be a powerful technique able to accurately identify gaseous organic compounds due to its great mass resolving power. Here we present the ammonium ion (NH4+) based CI-Orbitrap as a technique capable of measuring a wide range of gaseous OOMs. The performance of the CI-(NH4+)-Orbitrap was compared with that of state-of-the-art mass spectrometers, including a nitrate ion (NO3-) based CI coupled to an atmospheric pressure interfaced to long time-of-flight mass spectrometer (APi-LTOF), a new generation of proton transfer reaction-TOF mass spectrometer (PTR3-TOF), and an iodide (I-) based CI-TOF mass spectrometer equipped with a Filter Inlet for Gases and AEROsols (FIGAERO-CIMS). The instruments were deployed simultaneously in the Cosmic Leaving OUtdoors Droplets (CLOUD) chamber at the European Organization for Nuclear Research (CERN) during the CLOUD14 campaign in 2019. Products generated from α-pinene ozonolysis across multiple experimental conditions were simultaneously measured by the mass spectrometers. NH4+-Orbitrap was able to identify the widest range of OOMs (i.e., O = 2), from low oxidized species to highly oxygenated volatile organic compounds (HOM). Excellent agreements were found between the NH4+-Orbitrap and the NO3--LTOF for characterizing HOMs and with the PTR3- TOF for the less oxidized monomeric species. A semi-quantitative information was retrieved for OOMs measured by NH4+-Orbitrap using calibration factors derived from this side-by-side comparison. As other mass spectrometry techniques used during this campaign, the detection sensitivity of NH4+-Orbitrap to OOMs is greatly affected by relative humidity, which may be related to changes in ionization efficiency and/or multiphase chemistry. Overall, this study shows that NH4+ ion46 based chemistry associated with the high mass resolving power of the Orbitrap mass analyzer can measure almost all-inclusive compounds. As a result, it is now possible to cover the entire range of compounds, which can lead to a better understanding of the oxidation processes. [ABSTRACT FROM AUTHOR]

New (a)biotic conditions, resulting from climate change, are expected to change disturbance dynamics, e.g., wind throw, forest fires and insect outbreaks, and their interactions. Unprecedented natural disturbance 30 dynamics might alter the capability of forest ecosystems to buffer atmospheric CO2 increases in the atmosphere, even leading to the risk that forests transform from sinks into sources of CO2. This study aims to enhance the capability of the ORCHIDEE land surface model to study the impacts of climate change on bark beetle dynamics and subsequent effects on forest functioning. The bark beetle outbreak model is based on previous work by Temperli et al. 2013 for the LandClim landscape model. The new implementation of this model in ORCHIDEE r7791 35 accounts for the following differences between ORCHIDEE and LandClim: (1) the coarser spatial resolution of ORCHIDEE, (2) the higher temporal resolution of ORCHIDEE, and (3) the pre-existing process representation of wind throw, drought, and forest structure in ORCHIDEE. Qualitative evaluation demonstrated the model's ability to simulate a wide range of observed post-disturbance forest dynamics: (1) resistance to bark beetle infestation even in the presence of windthrow events; (2) slow transition (3-7 years) from an endemic into an epidemic bark beetle population following medium intensity window events at cold locations; and (3) fast transition (1-3 years) from endemic to epidemic triggered by strong windthrow events. Although all simulated sites eventually recovered from disturbances, the time needed to recover varied from 5 to 10 years depending on the disturbance dynamics. In addition to enhancing the functionality of the ORCHIDEE model, the new bark beetle model represents a fundamental change in the way mortality is simulated as it replaces a framework in which mortality is conceived as a continuous process by one in which mortality is represented by abrupt events. Changing the mortality framework provided new insights into carbon balance estimates, showing the risk of overestimating the short-term sequestration potential under the commonly used continuous mortality framework. [ABSTRACT FROM AUTHOR]

Silvicultural treatments recommended to reduce damage by spruce budworm (SBW; Choristoneurafumiferana Clemens) include reducing balsam fir (Abies balsamea (L.) Mill.) abundance and age and increasing spruce (Picea spp.) and hardwood content. To evaluate the effect of these measures on forest timber supply, we assessed stand characteristics, disturbance history, and timber supply for an intensively managed eastern Quebec forest from 1985 to 2004, encompassing a major SBW outbreak. During this time, mean stand age declined from 55 to 51 years, and proportions of areas in balsam fir stands declined (42% to 27%), spruce-fir stabilized (12% to 11%), and mixedwoods increased (32% to 52%). We estimated forest vulnerability using softwood volume reductions following simulated outbreak scenarios of different severity (low, moderate, and high) and different effects of hardwood content in reducing spruce-fir defoliation. Volume reductions for outbreaks simulated to begin in either 1985 or 2004 were similar, ranging from 15%-46% (no hardwood effect in reducing defoliation) to 13%-39% (given a maximum hardwood content effect) for light and severe outbreaks, respectively. Considering the net detrimental effect of increased hardwood content on softwood timber supply, we question the dividends of promoting hardwoods and recommend increasing the combined use of plantations and weeding treatments to increase spruce content. Key words: spruce budworm outbreak, silviculture, protective effects of hardwoods, softwood timber supply, forest protection. Les traitements sylvicoles recommandes pour reduire les dommages lors d'epidemies de la tordeuse des bourgeons de l'epinette (TBE; Choristoneurafumiferana Clemens) incluent la reduction de l'abondance et de l'age du sapin (Abies balsamea (L.) Mill.) et l'augmentation de l'abondance d'epinettes (Picea spp.) et de feuillus. Afin d'evaluer l'effet de ces mesures sur l'approvisionnement en bois, nous avons evalue de 1985 a 2004 les caracteristiques, l'historique des perturbations et l'approvisionnement en resineux d'une foret de l'est du Quebec sous amenagement intensif et pendant une epidemie majeure de TBE. Pendant cette periode, l'age moyen des peuplements a chute de 55 a 51 ans, la proportion de peuplements de sapin a chute (42 % a 27 %), celle d'epinette-sapin s'est maintenue (12 %a 11 %) et celle mixte a augmente (32 % a 52 %). La vulnerabilite des forets a ete estime a partir des reductions de volume resineux suivant des simulations d'epidemies de differentes severite (faible, moderee et severe) et effet des feuillus sur la reduction de la defoliation des hotes. Les pertes de bois des epidemies debutant en 1985 ou 2004 se sont averees similaires et s'elevaient de 15 %-46 % (aucun effet des feuillus) a 13 %-39 % (effet des feuillus maximal) pour les epidemies legeres et severes. Etant donne la difficulte d'augmenter l'abondance d'epinettes et les pertes nettes de production resineuse liees au contenu eleve en feuillus, nous remettons en question les benefices lies a la preservation des feuillus et recommandons une utilisation accrue du controle de la vegetation en plantation pour augmenter l'abondance d'epinette. Mots-cles : epidemie de tordeuse des bourgeons de l'epinette, sylviculture, effet de protection des feuillus, approvisionnement en bois resineux, protection des forets., Introduction The last spruce budworm (Choristoneura fumiferana Clemens; SBW) outbreak, which occurred from 1967 to 1992 in eastern Canada and in the United States (US), generated an estimated annual loss [...]

Sone Essoh, W.; Onguene, R.; Ndongo, B.; Nshagali, G.; Colmet-Daage, A.; Marie, G.; Iroume, J.; Stieglitz, T.; Besck, F.; Efole Ewoukem, T.; Tomedi Eyango, M.; Etame, J., and Braun, J.J., 2023. Using GIS and multicriteria analysis to map flood risk areas of the Tongo Bassa River Basin (Douala, Cameroon). Journal of Coastal Research, 39(3), 531–543. Charlotte (North Carolina), ISSN 0749-0208. The present study aimed to map the areas at risk of flooding in the Tongo Bassa watershed (42 km2) located in the heart of the Cameroonian economic capital (Douala) in the tropical zone of Central Africa, more precisely in the Wouri Estuary, at the bottom of the Gulf of Guinea. Like most of the world's major cities, Douala is subject to floods. The methodological approach was to identify the flooding risk determinants in the area from an extensive literature review and field surveys and then analyze these factors and map areas at risk of flooding using the analytical hierarchy process approach coupled with the GIS environment. The results revealed that four parameters of the natural environment (elevation, drainage density, distance to the river, and land cover) were the factors that mainly influenced the phenomenon of flooding in the region. Three major classes of flood risk were highlighted: low risk, medium risk, and high risk. To validate the effectiveness of the flood risk map obtained, the flood points collected in the field were cross-checked for ground truth after a flood occurred in the watershed. This cross-check between the resulting map and the flood points using GIS tools showed a good representation of the flooded area. This result is quite interesting because the areas where the risk of flooding is high are consistent with those where flooding is most frequent. The presented results constitute a basic decision support tool for the management of flood zones by the public authorities and the decentralized territorial communities of the city of Douala. [ABSTRACT FROM AUTHOR]

Most land surface models can, depending on the simulation experiment, calculate the vegetation distribution and dynamics internally by making use of biogeographical principles or use vegetation maps to prescribe spatial and temporal changes in vegetation distribution. Irrespective of whether vegetation dynamics are simulated or prescribed, it is not practical to represent vegetation across the globe at the species level because of its daunting diversity. This issue can be circumvented by making use of 5 to 20 plant functional types (PFTs) by assuming that all species within a single functional type show identical land–atmosphere interactions irrespective of their geographical location. In this study, we hypothesize that remote-sensing-based assessments of aboveground biomass can be used to constrain the process in which real-world vegetation is discretized in PFT maps. Remotely sensed biomass estimates for Africa were used in a Bayesian framework to estimate the probability density distributions of woody, herbaceous and bare soil fractions for the 15 land cover classes, according to the United Nations Land Cover Classification System (UN-LCCS) typology, present in Africa. Subsequently, the 2.5th and 97.5th percentiles of the probability density distributions were used to create 2.5 % and 97.5 % credible interval PFT maps. Finally, the original and constrained PFT maps were used to drive biomass and albedo simulations with the Organising Carbon and Hydrology In Dynamic Ecosystems (ORCHIDEE) model. This study demonstrates that remotely sensed biomass data can be used to better constrain the share of dense forest PFTs but that additional information on bare soil fraction is required to constrain the share of herbaceous PFTs. Even though considerable uncertainties remain, using remotely sensed biomass data enhances the objectivity and reproducibility of the process by reducing the dependency on expert knowledge and allows assessing and reporting the credible interval of the PFT maps which could be used to benchmark future developments. [ABSTRACT FROM AUTHOR]

New particle formation in the upper free troposphere is a major global source of cloud condensation nuclei (CCN)1–4. However, the precursor vapours that drive the process are not well understood. With experiments performed under upper tropospheric conditions in the CERN CLOUD chamber, we show that nitric acid, sulfuric acid and ammonia form particles synergistically, at rates that are orders of magnitude faster than those from any two of the three components. The importance of this mechanism depends on the availability of ammonia, which was previously thought to be efficiently scavenged by cloud droplets during convection. However, surprisingly high concentrations of ammonia and ammonium nitrate have recently been observed in the upper troposphere over the Asian monsoon region5,6. Once particles have formed, co-condensation of ammonia and abundant nitric acid alone is sufficient to drive rapid growth to CCN sizes with only trace sulfate. Moreover, our measurements show that these CCN are also highly efficient ice nucleating particles—comparable to desert dust. Our model simulations confirm that ammonia is efficiently convected aloft during the Asian monsoon, driving rapid, multi-acid HNO3–H2SO4–NH3 nucleation in the upper troposphere and producing ice nucleating particles that spread across the mid-latitude Northern Hemisphere.By performing experiments under upper tropospheric conditions, nitric acid, sulfuric acid and ammonia can form particles synergistically, at rates orders of magnitude faster than any two of the three components. [ABSTRACT FROM AUTHOR]

Biogenic organic precursors play an important role in atmospheric new particle formation (NPF). One of the major precursor species is α -pinene, which upon oxidation can form a suite of products covering a wide range of volatilities. Highly oxygenated organic molecules (HOMs) comprise a fraction of the oxidation products formed. While it is known that HOMs contribute to secondary organic aerosol (SOA) formation, including NPF, they have not been well studied in newly formed particles due to their very low mass concentrations. Here we present gas- and particle-phase chemical composition data from experimental studies of α -pinene oxidation, including in the presence of isoprene, at temperatures (- 50 and - 30 ∘ C) and relative humidities (20 % and 60 %) relevant in the upper free troposphere. The measurements took place at the CERN Cosmics Leaving Outdoor Droplets (CLOUD) chamber. The particle chemical composition was analyzed by a thermal desorption differential mobility analyzer (TD-DMA) coupled to a nitrate chemical ionization–atmospheric pressure interface–time-of-flight (CI-APi-TOF) mass spectrometer. CI-APi-TOF was used for particle- and gas-phase measurements, applying the same ionization and detection scheme. Our measurements revealed the presence of C 8-10 monomers and C 18-20 dimers as the major compounds in the particles (diameter up to ∼ 100 nm). Particularly, for the system with isoprene added, C 5 (C 5 H 10 O 5-7) and C 15 compounds (C 15 H 24 O 5-10) were detected. This observation is consistent with the previously observed formation of such compounds in the gas phase. However, although the C 5 and C 15 compounds do not easily nucleate, our measurements indicate that they can still contribute to the particle growth at free tropospheric conditions. For the experiments reported here, most likely isoprene oxidation products enhance the growth of particles larger than 15 nm. Additionally, we report on the nucleation rates measured at 1.7 nm (J1.7nm) and compared with previous studies, we found lower J1.7nm values, very likely due to the higher α -pinene and ozone mixing ratios used in the present study. [ABSTRACT FROM AUTHOR]

Most land surface models can either calculate the vegetation distribution and dynamics internally by making use of biogeographical principles or use vegetation maps to prescribe spatial and temporal changes in vegetation distribution. Irrespective of whether vegetation dynamics are simulated or prescribed, it is not practical to represent vegetation across the globe at the species level because of its daunting diversity. This issue can be circumvented by making use of 5 to 20 plant functional types (PFT) by assuming that all species within a single functional type show identical land-atmosphere interactions irrespective of their geographical location. In this study, we hypothesize that remote-sensing based assessments of above-ground biomass can be used to refine discretizing real-world vegetation in PFT maps. Remotely sensed biomass estimates for Africa were used in a Bayesian framework to estimate the probability density distributions of woody, herbaceous, and bare soil fractions for the 15 land cover classes, according to the UN- LCCS typology, present in Africa. Subsequently, the 2.5 and 97.5 percentile of the probability density distributions were used to create 2.5 % and 97.5 % confidence interval PFT maps. Finally the original and refined PFT maps were used to drive biomass and albedo simulations with the ORCHIDEE model. This study demonstrates that remotely sensed biomass data can be used to better constrain PFT maps. Among the advantages of using remotely sensed biomass data were the reduced dependency on expert knowledge and the ability to report the confident interval of the PFT maps. Applying this approach at the global scale, would increase confidence in the PFT maps underlying assessments of present day biomass stocks. [ABSTRACT FROM AUTHOR]

The current paper describes a novel passive aeration simultaneous nitrification and denitrification (PASND) zeolite amended biofilm reactor that removes organic carbon and nitrogen from wastewater with low-energy consumption. Next to the ammonium oxidizing bacteria (AOB), this reactor contained naturally enriched glycogen accumulating organisms (GAOs) and zeolite powder to initially adsorb BOD (acetate) and ammonium (NH4+-N) from synthetic wastewater under anaerobic conditions. Draining of the treated wastewater exposed the biofilm directly to air enabling lowenergy oxygen supply by passive aeration. This allowed the adsorbed ammonium to be oxidized by the AOB and the produced nitrite and nitrate to be reduced simultaneously by the GAOs using the adsorbed BOD (stored as PHAs) as carbon source. Overall, with an operation mode of 1 h anaerobic and 4 h aerobic phase, the nutrient removal efficiency after single treatment was about 94.3% for BOD and 72.2% for nitrogen (NH4+-N). As high-energy aeration of the bulk solution for oxygen supply is completely avoided, the energy requirement of the proposed PASND biofilm reactor can be theoretically cut down to more than 50% compared to the traditional activated sludge process. [ABSTRACT FROM AUTHOR]

Abstract: Forest ecosystems contain several climate‐sensitive drivers that respond differentially to changes in climate and climate variability. For example, growth and regeneration processes are “stand‐scale” drivers, while natural disturbances operate at “landscape scale”. The relative contributions of these different scale drivers of change in ecosystems create great uncertainty when simulating potential responses of a forest to changes in climate. Here, we assess those contributions, along with harvesting effects, on biomass (both total and of individual species) in the southern boreal forest of Canada under three climate scenarios (RCP 2.6, RCP 4.5 and RCP 8.5). Projections were performed for three future 30‐year time periods, in four study regions located on an east–west transect, using a forest landscape model (LANDIS‐II), parameterized using a forest patch model (PICUS). Projected future impacts were assessed for each driver of change, and found to vary greatly among regions, species, future period and forcing scenarios. Fire, and stand‐scale climate‐induced impacts, had the strongest effects on forest vegetation, as well as on total and species’ biomass under most RCP scenarios, but the largest impacts occurred mostly after 2050, particularly with the RCP 8.5 scenario. The relative importance and trends in species‐specific impacts varied, both spatially and according to the different RCP scenarios. Western regions were generally more sensitive to stand‐scale climate‐induced changes, whereas eastern regions were more sensitive to changes in fire regime. Our study also highlights the importance of considering the prevalence of species‐level functional traits when assessing the sensitivity of forest landscapes to a given driver of change in the context of increasing anthropogenic climate forcing. Synthesis. Increases in fire activity, and direct impacts of climate change on forest growth and regeneration, will be the most important drivers of future changes in southern boreal forest landscapes. [ABSTRACT FROM AUTHOR]

We aimed to evaluate the importance of modulations of within-tree carbon (C) allocation by water and low-temperature stress for the prediction of annual forest growth with a process-based model., A new C allocation scheme was implemented in the CASTANEA model that accounts for lagged and direct environmental controls of C allocation. Different approaches (static vs dynamic) to modelling C allocation were then compared in a model-data fusion procedure, using satellite-derived leaf production estimates and biometric measurements at c. 104 sites., The modelling of the environmental control of C allocation significantly improved the ability of CASTANEA to predict the spatial and year-to-year variability of aboveground forest growth along regional gradients. A significant effect of the previous year's water stress on the C allocation to leaves and wood was reported. Our results also are consistent with a prominent role of the environmental modulation of sink demand in the wood growth of the studied species., Data available at large scales can inform forest models about the processes driving annual and seasonal C allocation. Our results call for a greater consideration of C allocation drivers, especially sink-demand fluctuations, for the simulations of current and future forest productivity with process-based models. [ABSTRACT FROM AUTHOR]

Many natural terrestrial ecosystems, agroforestry systems, and, increasingly, forest plantations, are made of a mixture of species and display significant structural heterogeneity. Yet most carbon-based biophysical models are limited to homogeneous, monospecific canopies. We explored whether the spatial structure at the Font-Blanche experimental site, located in a mixed Mediterranean forest of Aleppo pine and holm oak in south-east France, could affect the components of the carbon and water cycles. We used NOTG, a new 3D, process-based, and individual-based model specifically developed to study the importance of the spatial structure on the carbon and water cycles of complex ecosystems. It incorporates processes involved in the energy, carbon, and water cycles at the tree (radiation interception, photosynthesis, phenology, allocation, senescence, transpiration), and soil (soil moisture, soil organic matter decomposition) levels. It is designed to handle various plant phenological types (deciduous, non opportunistic evergreen, and opportunistic evergreen), and a comprehensive description of plant C pools. The model is designed to study water and carbon fluxes at the stand scale over one to a few years. In this study, NOTG was parameterized for the Font-Blanche forest and two five-year simulations were made using either the full 3D representation, or a simplified 1D representation. Comparison of model outputs against observations at the tree, soil, and ecosystem scales, showed a much better accuracy when using the 3D representation. This illustrates the dependence of plant and ecosystem function to the above- and below-ground spatial structures, and the usefulness of such detailed models when dealing with structurally complex ecosystems. [ABSTRACT FROM AUTHOR]

Difficulties in accounting for the fine scale nature of ecological processes in large-scale simulations constitute an important issue in ecology. Among existing methods, meta-modelling, that is creating a statistical emulator of a model, has seen very few applications in ecology. Yet, meta-modelling methods are well advanced in the field of engineering., We adapted and applied a meta-modelling approach to a case study typical of the complexity found in ecosystems. It involved a highly detailed, individual-based and spatially explicit biophysical model (noTG). The model was parameterized for a multi-specific, spatially heterogeneous forest. Our goal was to increase its temporal domain of applicability by obtaining a meta-model of its light interception module many times faster., The meta-model was constructed from a series of simulations with noTG, following a latin hypercube design. Several meta-modelling techniques were compared, with neural networks providing the best results. The meta-model accurately reproduced the behaviour of noTG across a range of variables and organization levels. It was also 62 times faster., These result show that meta-modelling can be a practical tool in ecology and represents a highly powerful way to change the scope of a model while still accounting for fine details. [ABSTRACT FROM AUTHOR]

• Future climate in the Mediterranean will be warmer and drier. • We used the biophysical model NOTG on a mixed Mediterranean forest. • Predicted productivity and carbon sequestration (NEP) increased under climate change. • However the main trend in NEP was a decrease due to forest maturing. Climate models predict increased drought conditions for the Mediterranean region, putting forests under increasing risk from direct or indirect effects of droughts. On the other hand, increasing CO 2 and longer growing seasons could compensate the negative impacts of more intense droughts on forest productivity and carbon sequestration. Furthermore, large areas of Mediterranean forests are relatively young and unmanaged, and maturing usually tends to decrease carbon sequestration. We conducted a simulation study to explore the interplay between climate, CO 2 , and maturing, on forest net primary production (NPP) and net ecosystem production (NEP) over the 2000–2100 period. We used the Not Only Tree/Grass (NOTG) model, which is individual-based, process-oriented, and spatially explicit. We applied the model to the Font-Blanche experimental site, a typical mixed Mediterranean forest dominated by Aleppo pines and holm oaks. Simulations under three climate scenarios (current, moderate change, severe change) suggest that NPP could be enhanced by climate change, both due to higher CO 2 and longer growing seasons. On the other hand NEP would only be temporarily enhanced by climate change. The largest effect, however, was a decrease of NEP over time for all scenarios, due to forest maturing, with heterotrophic respiration progressively catching up with NPP. This implies that, regardless of climate change, the sink capacity of large unmanaged forest areas in southern Europe could strongly diminish during the 21st century. [ABSTRACT FROM AUTHOR]

Sea ice, which is present 3-4 months each winter in the St. Lawrence estuary, is a significant sediment transport agent in the intertidal and nearshore areas of rock coasts. Over five winters (2012-2017), we surveyed the movements of large boulders (1-5 m) on a shore platform of the south coast of the St. Lawrence marine estuary, at Sainte-Luce (Quebec). Winter transport of 100 boulders, tagged with an electronic chip, was measured using a differential GPS. 90% of the boulders were mobile during at least one of the studied winters, mostly pushed on a short distance by ice-floes. Long distance movements of boulders by ice-rafting were less frequent, the transport exceeded 5 m in only 19% of the displacements (maximum: 152 m). Boulder transport seams relatively unpredictable with an interannual variability and a great spatial variability. Nevertheless, morphology of the rock coast appears as the key parameter explaining differences in transport. The boulders isolated on the shore platform were transported over greater distances than the ones jammed by other boulders on the rocky platform or those located on a cobble pavement or a boulder barricade. Boulder transport capacity is also different depending on ice conditions. Thus, during the mild winter, with low ice coverage, displacements were shorter and less numerous than during the cold winters. During one winter, three boulders were equipped with an accelerometer to determine the periods of movement of the boulders during the sea-ice season. The 24 transport episodes recorded were compared to marine, meteorological and ice conditions, based on acoustic wave and current sensor data, climatic data and image analysis from an in situ camera. Half of these episodes took place at the beginning of the pleniglacial stage, when the lower-icefoot partially broke up or moved due to a high tide or a storm. The other episodes proceeded at the end of the ice period, during the thermal destruction of the lower-icefoot. Meteo-marine conditions during these ice break-up (abundance of ice-floes, wind, waves and currents) affect direction and extent of the transports. [ABSTRACT FROM AUTHOR]

To identify risk factors for acute choroidal ischemia (ACI) after intra-arterial chemotherapy (IAC) for retinoblastoma. Retrospective cohort study. Two hundred twenty patients (248 eyes) treated with IAC in Lausanne between November 2008 and September 2019 (665 procedures). All patients were evaluated on a monthly basis with fundus photography and fluorescein angiography before and after each IAC injection. Acute choroidal ischemia, defined as any new choroidal ischemia clinically diagnosed within 35 days after an IAC injection, were noted. Eyes with choroidal complications diagnosed later than 35 days after the last IAC injection (n = 7) or those for which the status of the choroid was not assessable (n = 35) were excluded. Specific procedure parameters and treatment regimens were compared between the group of eyes with and without ACI. Procedure-related risk factors for ACI after IAC injection and visual acuity assessment in the group of eyes with ACI. Acute choroidal ischemia developed in 35 of 206 included eyes after a mean of 2 injections. No differences were found between the two study groups regarding age at first IAC injection, disease grouping at diagnosis, previously administered treatments, number of IAC injections, drug dose, mean injection time, injection method (pulsatile vs. continuous), or concomitant intravitreal melphalan use. Treatment regimen (melphalan vs. combined melphalan plus topotecan; P < 0.05), catheterization route (internal carotid artery vs. external carotid or posterior communicating artery; P < 0.001), and catheterization type (occlusive into the ophthalmic artery [OA] vs. nonocclusive; P < 0.001) were included in multivariate analysis, and occlusive catheterization was identified as an independent risk factor for ACI (P < 0.001). In the subgroup undergoing an occlusive procedure, placement of the catheter tip into the OA distal third versus medial and proximal thirds (P = 0.04) and a mean catheter diameter-to-OA lumen ratio of 0.6 or more (P < 0.001) were correlated significantly with ACI. Complete vision loss was noted in 27% of the eyes with ACI that were old enough for visual assessment (n = 9/33), whereas 33% maintained a useful vision ranging between 0.1 and 0.8 (n = 11/33). Catheterization of the OA should be attempted from an ostial position or an external carotid approach to minimize the risk of potentially vision-threatening choroidal complications. [ABSTRACT FROM AUTHOR]

The article describes the case of a 76-year-old woman with herpes zoster ophthalmicus complicated by orbital apex syndrome. Case highlights include oral famciclovir and amoxicillin given for herpes zoster ophthalmicus, varicella zoster virus according to polymerase chain reaction in cerebrospinal fluid, and the impact of ischaemic stroke with right hemiplegia on the patient's progress.

Iodine oxoacids are recognised for their significant contribution to the formation of new particles in marine and polar atmospheres. Nevertheless, to incorporate the iodine oxoacid nucleation mechanism into global simulations, it is essential to comprehend how this mechanism varies under various atmospheric conditions. In this study, we combined measurements from the CLOUD (Cosmic Leaving OUtdoor Droplets) chamber at CERN and simulations with a kinetic model to investigate the impact of temperature, ionisation, and humidity on iodine oxoacid nucleation. Our findings reveal that ion-induced particle formation rates remain largely unaffected by changes in temperature. However, neutral particle formation rates experience a significant increase when the temperature drops from +10 °C to -10 °C. Running the kinetic model with varying ionisation rates demonstrates that the particle formation rate only increases with a higher ionisation rate when the iodic acid concentration exceeds 1.5 × 10 7 cm -3 , a concentration rarely reached in pristine marine atmospheres. Consequently, our simulations suggest that, despite higher ionisation rates, the charged cluster nucleation pathway of iodic acid is unlikely to be enhanced in the upper troposphere by higher ionisation rates. Instead, the neutral nucleation channel is likely to be the dominant channel in that region. Notably, the iodine oxoacid nucleation mechanism remains unaffected by changes in relative humidity from 2% to 80%. However, under unrealistically dry conditions (below 0.008% RH at +10 °C), iodine oxides (I 2 O 4 and I 2 O 5 ) significantly enhance formation rates. Therefore, we conclude that iodine oxoacid nucleation is the dominant nucleation mechanism for iodine nucleation in the marine and polar boundary layer atmosphere., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

Aerosols formed and grown by gas-to-particle processes are a major contributor to smog and haze in megacities, despite the competition between growth and loss rates. Rapid growth rates from ammonium nitrate formation have the potential to sustain particle number in typical urban polluted conditions. This process requires supersaturation of gas-phase ammonia and nitric acid with respect to ammonium nitrate saturation ratios. Urban environments are inhomogeneous. In the troposphere, vertical mixing is fast, and aerosols may experience rapidly changing temperatures. In areas close to sources of pollution, gas-phase concentrations can also be highly variable. In this work we present results from nucleation experiments at -10 °C and 5 °C in the CLOUD chamber at CERN. We verify, using a kinetic model, how long supersaturation is likely to be sustained under urban conditions with temperature and concentration inhomogeneities, and the impact it may have on the particle size distribution. We show that rapid and strong temperature changes of 1 °C min -1 are needed to cause rapid growth of nanoparticles through ammonium nitrate formation. Furthermore, inhomogeneous emissions of ammonia in cities may also cause rapid growth of particles., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The main nucleating vapor in the atmosphere is thought to be sulfuric acid (H 2 SO 4 ), stabilized by ammonia (NH 3 ). However, in marine and polar regions, NH 3 is generally low, and H 2 SO 4 is frequently found together with iodine oxoacids [HIO x , i.e., iodic acid (HIO 3 ) and iodous acid (HIO 2 )]. In experiments performed with the CERN CLOUD (Cosmics Leaving OUtdoor Droplets) chamber, we investigated the interplay of H 2 SO 4 and HIO x during atmospheric particle nucleation. We found that HIO x greatly enhances H 2 SO 4 (-NH 3 ) nucleation through two different interactions. First, HIO 3 strongly binds with H 2 SO 4 in charged clusters so they drive particle nucleation synergistically. Second, HIO 2 substitutes for NH 3 , forming strongly bound H 2 SO 4 -HIO 2 acid-base pairs in molecular clusters. Global observations imply that HIO x is enhancing H 2 SO 4 (-NH 3 ) nucleation rates 10- to 10,000-fold in marine and polar regions.

Purpose: Despite widely disseminated guidelines, pneumococcal and influenza vaccination coverage (VC) remains insufficient in patients with cancer receiving cancer treatment. We performed an interventional study to evaluate VC in patients with cancer treated at the medical oncology departments of three North-of-France hospitals and to assess the effect of medical staff training on VC in these patients., Methods: A standardized questionnaire assessed VC in adult patients with cancer receiving anticancer treatment at three day hospitals during December 2-7, 2019. Subsequently (January 2020), we organized educational training sessions for medical staff from each hospital to discuss the current vaccination guidelines. To assess the impact of training on pneumococcal and influenza VC, we re-administered the same questionnaire in March 2020. Because there are no specific guidelines on Diphtheria-Tetanus-Pertussis (DTP) vaccination and no improvement was expected, DTP VC acted as an internal control., Results: In total, 272 patients from all three hospitals were enrolled in the "before study"; 156 patients from only two hospitals were enrolled in the "after study" as medical training and data collection at the third were impossible because of administrative reasons and COVID-19 pandemic. The predictors were age for DTP VC; treatment center for pneumococcal VC; and age, sex, and tumor histology (adenocarcinoma vs. others) for influenza VC. Neither influenza VC (42.6% vs. 55.1%, p = 0.08), nor pneumococcal VC were significantly improved post-intervention (11.8% vs. 15.4%, p = 1). There seems to be a small effect in the most fragile for influenza VC., Conclusion: As expected, VC was very low in patients with cancer, consistent with the literature. There was no impact of the intervention for pneumococcal and influenza VC., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Author(s).)