National Forests Office

Selective logging is a widely applied forest management strategy in the tropics, yet it is insufficiently documented how it affects the genetic and demographic processes of seedling recruitment in timber species in the Guiana Shield. Our study investigates how selective logging influences genetic diversity, gene dispersal, and seedling establishment in Dicorynia guianensis by comparing a logged and an unlogged forest plot in French Guiana. We genotyped 703 individuals using 66 nuclear SSR markers and applied parentage analyses to infer dispersal patterns and reproductive success. We analysed genetic diversity and spatial genetic structure across life stages, and tested whether seedling recruitment was associated with logging-related canopy openings. Genetic diversity indices were broadly similar between logged and unlogged plots, with no evidence of genetic erosion in adults or seedlings. Seedling establishment was associated with logging-induced canopy openings. Parentage analyses revealed shorter mean dispersal distances in the logged plot but substantial long-distance pollen flow, ensuring admixture and inter-plot connectivity. Reproductive success was more evenly distributed among mothers, whereas male contributions were skewed in the logged plot. Selective logging did not cause immediate genetic erosion but altered dispersal dynamics and reproductive patterns. These findings underline the resilience of D. guianensis under current management practices, while emphasizing the need for long-term monitoring of regeneration to ensure sustainable recruitment and evolutionary resilience across logging cycles. ### Competing Interest Statement The authors have declared no competing interest. Agence Nationale de la Recherche, ANR-10-LABX-25-01, ANR-24-PEFO-0006 Agence de la transition écologique Université de Guyane Université de Bordeaux, https://ror.org/057qpr032

conservation of raptors is challenging in managed forests because conservation plans must consider species' breeding and foraging requirements concurrently, which may range from tree to landscape scales. Our aim in this study was to identify ecological elements benefiting a guild of four large diurnal raptors (Eurasian Goshawk, Asturgentilis; Common Buzzard, Buteo buteo; Booted Eagle, Hieraaetus pennatus; and Osprey, Pandion haliaetus) occupying a 676-km2 lowland temperate mixed oak-Scots Pine (Quercus spp.-Pinus sylvestris) managed forest in central France. We used logistic regressions applied to 118 nests occupied in 2012, and a random sample of 149 control points to identify influential variables quantifying competition intensity and describing the nest tree, the nest area (200-m radius around nest), and the hunting territory (within 1-, 2-, and 5-km radii). Eurasian Goshawks, Booted Eagles, and Ospreys exclusively nested in pines, except for one nest each in oaks for the latter two species. Common Buzzards were less selective but still used pines more than oaks. All four raptors selected large trees (on average 45-60 cm diameter at breast height [dbh] depending on species), especially Booted Eagles and Ospreys. By comparison, logging and accessibility to frequently used foraging areas proved less important. All study species showed a fairly high tolerance to human disturbance, possibly as a result of limited logging near nesting sites during the breeding season. Eurasian Goshawk and Booted Eagle nests were more distant from conspecific nests than from control points, suggesting conspecific competition. In addition, Eurasian Goshawk, Booted Eagle, and Osprey nests were closer from heterospecific nests than to control points, revealing heterospecific aggregation. The results of our study stress the importance of conserving large pines, beyond the dbh at which they are usually cut in these managed forests (45 cm).

The Biomtrace_extension database contains 8341 RGB images of the butt end of 695 French oak logs. This database was created with the aim of developing biometric traceability methods based on realistic photo acquisitions in the field for tracking logs from the forest to primary processing. No such database was previously available. Photos of the same logs were taken on two dates several months apart, up to more than 100 days apart for some sites. Images were acquired in three specific cases in order to test the sensitivity and limitations of recognition algorithms under conditions that may occur in practice: (1) traceability based on photos taken before and after log extraction; (2) sensitivity of traceability to the quality of photos (angle of the shot and distance to the log); (3) robustness of traceability to partial or complete trimming of the log end. The database also includes manual reference measurements performed on the images, as well as outputs from image preprocessing algorithms. Tables containing site and image characteristics are also provided. The Biomtrace_extension database is available at https://doi.org/10.57745/RKDTKY and metadata are provided at: https://metadata-afs.nancy.inra.fr/geonetwork/srv/fre/catalog.search#/metadata/5f2842a0-15ec-48be-8f1c-e44334654cc5.

Mycorrhizal symbioses represent one of the most widespread and ecologically significant plant-microbe interactions, shaping plant nutrition, stress resilience, and ecosystem functioning. Beyond their role in nutrient exchange and systemic defense, growing evidence suggests that these symbioses also influence plant plasticity within and across generations through epigenetic regulation. These mechanisms operate throughout the mutualistic interaction, from fungal recognition and root colonization to symbiosis functioning, by regulating gene networks that control signaling, defense suppression, and nutrient exchange. By integrating environmental cues into potentially heritable gene regulatory states, epigenetic regulation fine-tunes within-generation responses and may also contribute to effects across generations, thereby influencing adaptation and resilience. The extent of mycorrhiza-induced epigenetic inheritance likely depends on the host's reproductive strategy and lifespan. Clonal propagation and shorter-lived hosts tend to preserve epigenetic marks, whereas sexual reproduction and longer-lived species show partial resetting. This contrast shapes offspring performance, ecological interactions, and evolutionary trajectories. Here, we synthesize current knowledge on the epigenetic regulation of mycorrhizal symbioses, draw parallels with other plant-microorganism interactions (including plant-pathogens and plant-endophytes), highlight its role in within-generation plasticity and propose a potential role across generations. We outline future research directions to disentangle the stability, ecological relevance, and evolutionary significance of mycorrhiza-mediated epigenetic inheritance.

Atmospheric deposition is a critical driver of biogeochemical cycling in forest ecosystems. Among the pathways of deposition, throughfall (TF) — precipitation that has interacted with the forest canopy — plays a significant role in the input of atmospheric substances and canopy leachates to the forest floor. We investigated the influence of airborne pollen deposited in TF on its chemical composition across 60 Level II plots of the ICP Forests network in eight European countries. Based on 196 TF samples collected during the 2018 early vegetative season, we identified 53 pollen taxa, with Pinus, Picea, Fagus, and Quercus accounting for 91.4