Le Lescuraeetum mutabilis Greter ex Wilm. 1962 dans le Massif central

The Lescuraeetum mutabilis Greter ex Wilm. 1962 (Neckeretea complanatae Marst. 1986) is an acidophilic corticolous association colonizing the base of the tortuous trunks of old beech trees, at the subalpine level or at the upper mountain level, within tracheophytic communities belonging respectively to the Acerion pseudoplatani (Oberdorfer 1957) Rameau in Rameau, Mansion & Dumé 1993 nom. nud., the Fagion sylvaticae Luquet 1926 (for neutrophilic communities) or the Luzulo luzuloidis-Fagion sylvaticae Lohmeyer & Tüxen in Tüxen 1954 (for acidophilic communities). This substratohygroclinophilic, psychrophilic association, strictly limited to high altitude forests, is characterized in the Massif central by the co-occurence of 4 species: Lescuraea saviana, L. mutabilis, Sciuro-hypnum reflexum and Sanionia uncinata. The high frequency of Lescuraea saviana is a regional originality of the association, considered insufficient to define a sub-association, but nevertheless allowing the individualization of a southern geographic race of this widely distributed association in the mountainous massifs of the European temperate zone. This cryophilic association is certainly highly sensitive to temperature increases and changes in precipitation regime and presents a strong conservation challenge.Le Lescuraeetum mutabilis Greter ex Wilm. 1962 (Neckeretea complanatae Marst. 1986) est une association corticole acidiphile colonisant la base des troncs tortueux des vieux hêtres, à l’étage subalpin, ou au montagnard supérieur, au sein de communautés trachéophytiques relevant respectivement de l’Acerion pseudoplatani (Oberdorfer 1957) Rameau in Rameau, Mansion & Dumé 1993 nom. nud., du Fagion sylvaticae Luquet 1926 (pour les communautés neutrophiles) ou du Luzulo luzuloidis-Fagion sylvaticae Lohmeyer & Tüxen in Tüxen 1954 (pour les communautés acidiphiles). Cette association substratohygroclinophile, psychrophile, strictement inféodée aux forêts alticoles, est caractérisée dans le Massif central par la présence de 4 espèces : Lescuraea saviana, L. mutabilis, Sciuro-hypnum reflexum et Sanionia uncinata. La haute fréquence de Lescuraea saviana est une originalité régionale de l’association, considérée comme insuffisante pour définir une sous-association, mais permettant cependant l’individualisation d’une race géographique méridionale de cette association largement répandue dans les massifs montagneux du domaine tempéré européen. Cette association cryophile présente certainement une grande sensibilité vis-à-vis de l’augmentation des températures et des modifications du régime de précipitation et possède un fort enjeu conservatoire

Validation nomenclaturale de l’association bryophytique Gymnomitrio corallioidis-Barbilophozietum sudeticae ass. nov., décrite du Puy de Dôme dans Hugonnot (2020).

The name of the new association described in the article by Hugonnot (2020) is not validly published because the phytosociological nomenclature code in force until 31 December 2020 (ICPN, Weber et al. 2000) did not allow a nomenclatural validation in the form of digital publication (art. 1). As of January 1, 2021, the new code (ICPN, Theurillat et al. 2020) is applicable. It specifies in article 1 the modalities of an effective digital publication. The purpose of this article is therefore to apply these modalities and to validate, according to the new code, the name of the association described in Hugonnot (2020). We refer to the latter article for a more precise description and a more complete bibliography.Le nom de l’association nouvelle décrite dans l’article d’Hugonnot (2020) n’est pas validement publiée car le code de nomenclature phytosociologique en cours jusqu’au 31décembre 2020 (ICPN, Weber et al. 2000) ne permettait pas une validation nomenclaturale sous forme de publication numérique (art. 1). A partir du 1er janvier 2021 c’est le nouveau code (ICPN, Theurillat et al. 2020) qui est applicable. Il précise dans l’article 1 les modalités d’une publication numérique effective. Le présent article a donc pour but d’appliquer ces modalités et de valider, selon le nouveau code, le nom de l’association décrite dans Hugonnot (2020). On se référera à ce dernier article pour une description plus précise et une bibliographie plus complète

Bryophytes of the Rhône alluvial complexes : flora, vegetation and functionality

Bryophytes are still too rarely used in ecological diagnostic, in particular in alluvial systems. The surveys carried out on a section of the Rhône, going from Jonage to Montélimar, allowed to draw up a first synthesis of the bryoflora and to describe the bryophyte vegetation of the Rhône alluvial complexes. The river dynamics (erosion, sedimentation, flooding) has fundamental consequences from floristic and vegetation points of view. The ecological constraints (hydric, nutrients), expressed from the main channel up to the flood plain, are responsible for a high floristic and vegetation richness. The anthropization, although a factor of enrichment, represents a major degradation of the typical bryoflora of the connected alluvial system. In highly artificialized systems, the disconnection allows the preservation of refugium habitats. The preservation of the bryophytic heritage rests on a subtle balance between re-energization of the river and management of the human pressureLes bryophytes sont encore trop peu utilisées dans les diagnostics écologiques, notamment dans les systèmes alluviaux. Les inventaires effectués sur un tronçon du Rhône, allant de Jonage à Montélimar, ont permis de dresser une premiere synthèse de la bryoflore et de décrire la végétation bryophytique des complexes alluviaux rhodaniens. La dynamique fluviale (érosion, sédimentation, inondation, etc.) a des conséquences fondamentales sur la composition floristique et sur la végétation bryophytique. Les contraintes écologiques (hydriques, trophiques, etc.), exprimées depuis le chenal principal jusqu'à la plaine d'inondation, se traduisent par une grande richesse en bryophytes et en végétations bryophytiques. L'anthropisation, bien qu'elle soit plutôt facteur d'enrichissement bryofloristique, entraîne une dégradation majeure de la bryoflore typique du système alluvial connecté. Dans les systèmes hautement artificialisés, la déconnection permet le maintien d'habitats-refuges pour des espèces et des communautés spécialisées. La conservation du patrimoine bryophytique repose sur un équilibre subtil entre redynamisation du fleuve et gestion de la pression humaine

Interest of micro-habitat bryophyte communities for the functional diagnosis of forest phytocenoses: the case of Chambons forest (Ardèche, France)

In the Chambons forest (Ardèche, France), the ecological determinism of bryophyte communities and their links with structural and functional characteristics were assessed. Substrate, light, and moisture are the main discriminating factors for the different recognized communities. Among the 10 groups identified, saxico-humicolous are the most diverse, followed closely by the corticolous. These microhabitats are all strictly dependent upon the various phases of the sylvigenesis cycle. Most of humicolous communities are determined by the successive phases of the organic matter cycle. The humicolous community richness relies heavily upon the diversity of potential repository (soil, rocks and base of trunks). Forest management leads to disturbances which severely restrict the spreading out of these bryophytic assemblages. To preserve the great bryological interest of this site and ecosystem, urgent conservation and management measures are requiredDans la forêt domaniale des Chambons (Ardèche, France), le déterminisme écologique des groupements bryophytiques a été étudié ainsi que leur dépendance vis-à-vis des caractéristiques structurelles et fonctionnelles du complexe forestier. Le substrat, la luminosité, et l'humidité sont les principaux facteurs discriminant les communautés des différents micro-habitats. Parmi les 10 groupements identifiés, les saxicohumicoles sont les plus diversifiés, suivis de près par les corticoles. Ces micro-habitats sont tous strictement dépendants des différentes phases du cycle sylvigénétique. Les stades successifs du cycle de la matière organique conditionnent la plupart des groupements humicoles. La richesse des communautés humicoles dépend étroitement de la diversité des réceptacles potentiels (sol, rochers et base des troncs). La gestion sylvicole des peuplements entraîne des perturbations qui limitent largement l'expression des communautés bryophytiques. La préservation du patrimoine bryophytique remarquable de ce site et plus largement de cet écosystème nécessite la mise en place urgente de mesures de conservation et de gestion

La végétation des sources thermominérales salées d’Auvergne

The authors accomplish a phytosociological study of the salt thermomineral spring vegetation in Auvergne. They follow a ‘braun-blanqueto-tüxenian’ approach of the association. Despite a large number of relevés carried out on the salty sites of Auvergne, the communities stay unknown as it seems necessary to synthesize them and clarify their phytosociological status.The authors carry out an analysis and a synthesis of 176 phytosociological relevés illustrating the communities of the twenty salty localities known in Auvergne. From 16 sites, 69 relevés were specifically produced as part of this study.Nine communities are presented on the floristical and synecological plan : three new associations and six new sub-associations are described.Les auteurs réalisent une étude phytosociologique de la végétation des sources thermominérales salées d’Auvergne, en s’inscrivant dans une approche «braun-blanqueto-tüxenienne» de l’association. Malgré un grand nombre de relevés réalisés sur les sites salés d’Auvergne, les groupements restent méconnus et il semblait nécessaire d’en réaliser la synthèse pour en préciser le statut phytosociologique.Après une rapide présentation du contexte physiographique des localités étudiées et un bref rappel des travaux phytosociologiques antérieurs, les auteurs réalisent une analyse et une synthèse de 176 relevés phytosociologiques illustrant les communautés de la vingtaine de localités salifères connues en Auvergne. Provenant de 16 sites, 69 relevés ont été spécifiquement réalisés dans le cadre de cette étude.Neuf groupements de rang association sont présentés sur le plan floristique et synécologique : trois associations et six sous-associations nouvelles sont décrites

Ultralow transmission loss in inhibited-coupling guiding hollow fibers

Attenuation in photonic bandgap guiding hollow-core photonic crystal fiber (HC-PCF) has not beaten the fundamental silica Rayleigh scattering limit (SRSL) of conventional step-index fibers due to strong core-cladding optical overlap, surface roughness at the silica cladding struts, and the presence of interface modes. Hope has been revived recently by the introduction of hypocycloid core contour (i.e., negative curvature) in inhibited-coupling guiding HCPCF. We report on several fibers with a hypocycloid core contour and a cladding structure made of a single ring from a tubular amorphous lattice, including one with a record transmission loss of 7.7 dB/km at ~750 nm (only a factor ~2 above the SRSL) and a second with an ultrabroad fundamental band with loss in the range of 10-20 dB/km, spanning from 600 to 1200 nm. The reduction in confinement loss makes these fibers serious contenders for light transmission below the SRSL in the UV-VIS-NIR spectral range and could find application in high-energy pulse laser beam delivery or gas-based coherent and nonlinear optics

Alleniella aegaea Blockeel & Hugonnot (Neckeraceae), a new moss species from the Aegean islands of Greece

A new moss species, Alleniella aegaea (Neckeraceae) is described and illustrated from the Greek islands of Crete, Samos and Evvia based on morphological and molecular evidence. According to phylogenetic analysis of nuclear ITS and plastid trnS-F sequences it is sister to A. complanata, which it also morphologically resembles, but it differs from that species e.g. in its distinctly flattened habit, lack of caducous branchlets, more rounded leaf apices, and shorter median laminal cells. Alleniella aegaea is dioicous and the sporophytes remain unknow

Assessment of atomic layer deposited TiO2 photocatalytic self-cleaning by quartz crystal microbalance

The self-cleaning properties emerging from photocatalytic effects consist in the elimination of an organic contamination layer by light-induced redox reactions. Quartz crystal microbalances (QCMs), monitoring the contaminant mass loss under UV illumination, were used to investigate this effect and its efficiency. A new setup dedicated to such purpose is introduced along with the results of a self-cleaning experiment performed with a 20-nm TiO2 thin film coated on a QCM by atomic layer deposition. In particular, a 10-nm paraffin oil thin film deposited under vacuum is shown to be degraded down to its complete removal according to a zeroth order photocatalytic reaction. Finally, the experimental opportunities offered by the new setup, such as a controlled environment composition, are presented.Peer reviewe

Spatioselective Modification of Bicompartmental Polymer Particles and Fibers via Huisgen 1,3-Dipolar Cycloaddition

Precise nano- and microscale control of the architecture of biodegradable biomaterials is desirable for several biotechnological applications such as drug delivery, diagnostics, and medical imaging. Herein, we combine electrohydrodynamic co-jetting and highly specific surface modification (via Huisgen 1,3-dipolar cycloaddition) to prepare particles and fibers with spatioselective surface modification. We first prepared biphasic particles and fibers from commercial poly(lactide- co -glycolide) copolymers via electrohydrodynamic co-jetting of two organic solutions loaded with fluorescent macromolecules and acetylene-modified PLGA derivatives. (i) Spatially controlled reaction of poly[lactide- co -(propargyl glycolide)] with O -(2-aminoethyl)- O ′-(2-azidoethyl)heptaethylene glycol and (ii) subsequent conversion of the newly introduced amino groups with fluorescence probes resulted in particles and fibers with surface modification of one hemisphere only.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/61239/1/1655_ftp.pd

An annotated checklist of bryophytes of Europe, Macaronesia and Cyprus

Introduction. Following on from work on the European bryophyte Red List, the taxonomically and nomenclaturally updated spreadsheets used for that project have been expanded into a new checklist for the bryophytes of Europe. Methods. A steering group of ten European bryologists was convened, and over the course of a year, the spreadsheets were compared with previous European checklists, and all changes noted. Recent literature was searched extensively. A taxonomic system was agreed, and the advice and expertise of many European bryologists sought. Key results. A new European checklist of bryophytes, comprising hornworts, liverworts and mosses, is presented. Fifteen new combinations are proposed. Conclusions. This checklist provides a snapshot of the current European bryophyte flora in 2019. It will already be out-of-date on publication, and further research, particularly molecular work, can be expected to result in many more changes over the next few years.Peer reviewe