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Most statistical models of microclimate focus on the difference or 'offset' between standardized air temperatures (macroclimate) and those of a specific habitat such as forest understorey, grassland or under a log. However, these offsets can fluctuate from positive to negative over a single day such that common practice consists in aggregating data into daily mean, minimum and maximum before modelling monthly offsets for each summary statistic. Here, we propose a more parsimonious and flexible approach relying on just two parameters: the slope and equilibrium. The slope captures the linear relationship between microclimate and macroclimate, while the equilibrium is the point at which microclimate equals macroclimate. Although applicable to other habitats, we demonstrate the relevance of our method by focusing on forest understoreys.We installed temperature sensors at 1‐m height inside forest stands and in nearby open grasslands equipped with standardized weather stations, across 13 sites in France spanning a wide climatic gradient. From a year of hourly temperatures and for each sensor, we established relationships between microclimate and macroclimate temperatures using two linear mixed‐effects models, during the leaf‐on (May–November) and leaf‐off period (December–April). We extracted the monthly equilibrium and slope for each sensor, and used another set of linear mixed‐effects models to investigate their main determinants.The slope was chiefly determined by stand structure variables interacting with the leaf‐on/leaf‐off period: stand type (conifer vs broadleaf); shade‐casting ability; stand age; dominant height; stem density; and cover of the upper and lower shrub layer. In contrast, forest structure had no explanatory power on the equilibrium. We found the equilibrium to be positively related to mean macroclimate temperature, interacting with the open/forest habitat.The method introduced here overcomes several shortcomings of modelling microclimate offsets. By demonstrating that the slope and equilibrium vary in predictable ways, we have established a general linkage between microclimate and macroclimate temperatures that can be applied to any location or time if we know the mean macroclimate temperature (equilibrium) and buffering or amplifying capacity of the habitat (slope). We also warn about methodological biases due to the reference used for macroclimate. [ABSTRACT FROM AUTHOR]

Aim: Climate warming reshuffles biological assemblages towards less cold‐adapted but more warm‐adapted species, a process coined thermophilization. However, the velocity at which this process is happening generally lags behind the velocity of climate change, generating a climatic debt the temporal dynamics of which remain misunderstood. Relying on high‐resolution time series of vegetation data from a long‐term monitoring network of permanent forest plots, we aim at quantifying the temporal dynamics – up to a yearly resolution – of the climatic debt in the understorey of temperate forests before identifying the key determinants that modulate it. Location: France. Time period: 1995–2017. Taxa studied: Vascular plants. Methods: We used the community temperature index (CTI) to produce a time series of understorey plant community thermophilization, which we subsequently compared to a time series of mean annual temperature changes over the same period and for the same sites. The direction and magnitude of the difference (i.e., the climatic debt) was finally analysed using linear mixed‐effect models to assess the relative contributions of abiotic and biotic determinants, including forest stand characteristics. Results: We found a significant increase in CTI values over time (0.08–0.09 °C/decade), whereas the velocity of mean annual temperature changes was three times higher over the same period (0.22–0.28 °C/decade). Hence, the climatic debt increased over time and was greater in forest stands with higher basal area or older trees as well as under warmer macroclimate. By contrast, a greater frequency of anthropogenic disturbances decreased the climatic debt, while natural disturbances and herbivory had no impact. Conclusions: Although often overlooked in understanding the climatic debt of forest biodiversity, changes in forest stand characteristics may modulate the climatic debt by locally modifying microclimatic conditions. Notably, the buffering effect of the upper canopy layer implies microclimate dynamics that may provide more time for understorey plant communities to locally adapt. [ABSTRACT FROM AUTHOR]

Abstract: Studying spatial patterns of soil engineers has become an important issue that may contribute to a better understanding of soil functioning. We investigated the spatial patterns of earthworm species assemblages in a recently settled and an old temperate pasture. Earthworms were sampled following a spatially explicit sampling design. Data were analysed using Spatial Analysis by Distance IndicEs methods to describe the main characteristics of earthworm spatial patterns: aggregation index, patch and/or gap number and size, and the frequencies of species association or dissociation. Ten lumbricid species composed the earthworm assemblages in both pastures, some of them displaying a spatial distribution characterized by clusters with areas of patches and gaps. By comparing aggregation indices between the pastures, an increase of the spatial organization level in the community was observed in the old pasture. We also observed differences between the pastures in the number of aggregated species, cluster characteristics, ratio between spatial association/dissociation and spatial overlap. We also found some significant relationships between species pairs that were already described in the literature, enabling us to discuss the possible nature of interactions. Our results suggest that earthworm spatial distribution and community assembly are likely driven by interspecific interactions at the local scale. [Copyright &y& Elsevier]

Study Objective: The aim of this study was to investigate the efficacy of a two-step patient blood management (PBM) program in red blood cell (RBC) transfusion requirements among patients undergoing elective cardiopulmonary bypass (CPB) surgery., Design: Prospective, non-randomized, two-step protocol design., Setting: Cardiac surgery department of Clinique Pasteur, Toulouse, France., Patients: 897 patients undergoing for elective CPB surgery., Interventions: We conducted a two-steps protocol: PBMe and PBMc. PBMe involved a short quality improvement program for health care workers, while PBMc introduced a systematic approach to pre- and postoperative correction of deficiencies, incorporating iron injections, oral vitamins, and erythropoiesis-stimulating agents., Measurements: The PBM program's effectiveness was evaluated through comparison with a pre-PBM retrospective cohort after propensity score matching. The primary objective was the proportion of patients requiring RBC transfusions during their hospital stay. Secondary objectives were also analyzed., Main Results: After matching, 343 patients were included in each group. Primary outcomes were observed in 35.7% (pre-PBM), 26.7% (PBMe), and 21.1% (PBMc) of patients, resulting in a significant reduction (40.6%) in the overall RBC transfusion rate. Both the PBMe and PBMc groups exhibited significantly lower risks of RBC transfusion compared to the pre-PBM group, with adjusted odds ratios of 0.59 [95% CI 0.44-0.79] and 0.44 [95% CI 0.32-0.60], respectively. Secondary endpoints included reductions in transfusions exceeding 2 units, total RBC units transfused, administration of allogeneic blood products, and total bleeding volume recorded on Day 1. There were no significant differences noted in mortality rates or the duration of hospital stays., Conclusions: This study suggests that health care education and systematic deficiency correction are associated with reduced RBC transfusion rates in elective CPB surgery. However, further randomized, controlled studies are needed to validate these findings and refine their clinical application., Competing Interests: Declaration of competing interest All the authors declare no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)