Comments on the flora of Rachgoun island (north-west Algeria)

La parution récente dans la Revue d’Écologie (Terre et Vie) d’une étude consacrée à l’impact des goélands sur la végétation de l’île Rachgoun en Algérie a motivé la publication d’une liste floristique personnelle de l’île datant de 2006 mais demeurée inédite. Pour des raisons méthodologiques, la publication en question fournissait une liste floristique partielle qu’il était utile de compléter ici. Par ailleurs, elle comportait également quelques incertitudes voire erreurs qu’il est apparu important de corriger. Certaines d’entre elles sont dues à la difficulté d’identification avec les flores classiques et/ou le mésusage des index synonymiques récents. D’autres sont dus au non-renseignement des types biologiques sensu Raunkiaer dans ces mêmes flores classiques. Des solutions simples et efficaces pour pallier ces insuffisances chroniques dans le domaine de la botanique maghrébine sont proposées.The recent publication in the Revue d'Écologie (Terre et Vie) of a study on the impact of gulls on the vegetation of Rachgoun island in Algeria prompted the publication of a personal floristic list of the island established in 2006 but remained unpublished. For methodological reasons, the publication in question provided a partial list of plants that it was useful to complete here. Moreover, it also contained some uncertainties or errors that it seemed important to correct. Some of them are due to having difficulty with conventional floras and/or misuse of recent synonymous index. Others are due to non-intelligence of biological types sensu Raunkiaer in these classical floras. Simple and effective solutions to address these chronic shortcomings in the field of Maghrebian botany are proposed

Synchronic study of the influence of ovine grazing and installation of protective fencing on the vegetation of the Luberon calcareous grassy areas (Provence, France)

Les auteurs étudient les effets sur la végétation de la mise en défens contre le pâturage ovin, sur une série de petits enclos grillagés, en deux sites du Parc naturel régional du Luberon (Provence, SE-France). Les deux sites présentent des problématiques légèrement différentes : dans le Petit Luberon, les enclos ont été posés lors de la reprise des activités pastorales qui avaient été interrompues ; dans le Grand Luberon, ils ont été posés alors que le pâturage n’a jamais cessé d’être pratiqué. Une approche synchronique a consisté à comparer l’intérieur de l’enclos avec l’extérieur, considérant que le milieu était homogène au moment de la pose. La comparaison est effectuée à plusieurs niveaux: la dérive physionomique, la dérive floristique et la dérive écologique. Pour cela deux méthodes complémentaires de traitement numérique sont utilisées. Un aspect patrimonial est également abordé sous l’angle de la biogéographie.The authors study the effects on vegetation caused by protective fencing against ovine grazing, on a series of small wire-fenced enclosures located on two sites of the Luberon regional nature Park (Provence, South-East France). The two sites present slightly different sets of problems : in the Petit Luberon massif, enclosures were put in place during the resumption of grazing activities, that were interrupted in the past ; in the Grand Luberon massif they were put in place on spots where grazing had never stopped being practised. A synchronic approach consisted in comparing the inside of the enclosure with the outside, taking into account that the environment was homogeneous at the time of the setting up. The comparison is made at several levels : physiognomic drift, floristic drift and ecological drift. In order to do so, two complementary numerical data processing methods are used. A patrimonial aspect is also dealt with

A contribution to the knowledge of orchids in the Aurès (N.-E. Algeria): inventory, cartography, taxonomy and ecology

À l’occasion de diverses études de la flore et de la végétation du massif de l’Aurès (N.-E. de l’Algérie), les orchidées ont fait l’objet d’un inventaire spécifique accompagné de relevés phytoécologiques conjoints. En quatorze années, seulement neuf taxons répartis sur quinze localités ont été inventoriés : Cephalanthera longifolia, Epipactis helleborine, Himanthoglossum hircinum subsp. hircinum, Ophrys lutea subsp. lutea, Ophrys scolopax subsp. apiformis, Ophrys subfusca subsp. subfusca, Ophrys tenthredinifera subsp. ficalhoana, Orchis olbiensis, Orchis purpurea subsp. purpurea. A ceux-ci s’ajoutent d’autres espèces signalées dans la littérature pour ce même massif ou dans le massif voisin de Belezma. Ces observations nous ont permis de confirmer la taxinomie de certains taxons qui demeurait assez confuse dans la littérature récente. Des analyses multidimensionnelles ont mis en évidence, d’une part la typologie des stations et d’autre part certaines variables environnementales déterminant la distribution de ces espèces dans cette région. En raison de la vulnérabilité alarmante des sites visités et des menaces, notamment anthropiques, auxquelles ils sont soumis, une réflexion sur la protection des habitats et de leurs hôtes apparaît urgente.From various flora and vegetation studies of the Aurès Massif (northeast of Algeria), the orchids have been the subject of a specific inventory coupled with a phytoecological survey. After fourteen years, only nine species in fifteen localities have been recorded, including following taxa: Cephalanthera longifolia, Epipactis helleborine, Himanthoglossum hircinum subsp. hircinum, Ophrys luteasubsp. lutea, Ophrys scolopax subsp. apiformis, Ophrys subfusca subsp. subfusca, Ophrys tenthredinifera subsp. ficalhoana, Orchis olbiensis, Orchis purpurea subsp. purpurea. In addition to those ones, other species are reported in the literature in this massif or in the nearby massif of Belezma. These observations allowed us to confirm the taxonomy of some taxa which are still confused in the recent literature. The multidimensional analyses have revealed the station typology and some environmental variables that determine the distribution of these species in this region. Due to the alarming vulnerability of these sites and the threats, especially anthropogenic, to which they are subjected, a reflection to protect the habitats and their hosts seems to be urgent

Phytogeographical study of the forest massifs of Kéfrida, a neglected sector of the Babors important plant area (Northeastern Algeria)

Afin d’apporter une meilleure connaissance sur la flore de Petite Kabylie (Béjaïa, Algérie), dans l’objectif de conservation du patrimoine naturel, une étude phytogéographique a été menée sur la végétation forestière dans deux massifs montagneux peu étudiés du secteur de Kéfrida, mitoyen de la ZIP (zone importante pour les plantes) des Babors. L’inventaire floristique réalisé au niveau des groupements forestiers de Chêne zéen (Quercus canariensis Willd.), de Chêne afarès (Q. afares Pomel) et des pelouses de montagne a permis de comptabiliser 332 espèces de plantes vasculaires. En plus des 205 (62 %) espèces méditerranéennes qu’il abrite, le site est remarquable par la présence de 37 (11 %) endémiques ou sub-endémiques algériennes et surtout 79 (23 %) espèces de l’ensemble holarctique non méditerranéen. L’analyse du spectre biologique brut montre une dominance significative des hémicryptophytes (48 %) sur les autres formes de vie (7,2 – 22,5 %). Cette zone constitue un refuge actuel exceptionnel pour une flore d’origine non méditerranéenne et/ou endémique, dans un contexte de réchauffement climatique. On note la présence de quatorze espèces déterminantes pour le secteur de Kéfrida étudié, dont huit en commun avec la ZIP des Babors et celle d’Akfadou et quatre en commun avec les ZIPs de Djurdjura et des monts de la Medjerda. La zone étudiée présente aussi un nombre appréciable de plantes importantes pour l’Algérie. Cette présence d’espèces déterminantes et/ou importantes pour le pays permet de classer le secteur de Kéfrida comme une extension de la ZIP des Babors.In order to provide a better knowledge of the flora of Little Kabylia (Bejaïa, Algeria), with an objective of conservation of natural heritage, a phytogeographical study was conducted on forest vegetation in two understudied mountains in the area of Kéfrida, adjoining the IPA (important plants area) of the Babors. The floristic surveys were conducted in a Zeen and an Afares oak (Quercus canariensis Willd. and Q. afares Pomel respectively) forests as well as mountain grasslands. The sampling allowed us to inventory 332 species of vascular plants. Besides the 205 (62 %) Mediterranean species it houses, the site is remarkable by the presence of 37 (11 %) Algerian endemics or sub-endemics and, above all, 79 (23 %) species from the non-Mediterranean Holarctic subset. Analysis of the global biological spectrum showed the significant dominance of hemicryptophytes (48 %) over the other life-forms (7.2 - 22.5 %). This area is an exceptional current refuge for non-Mediterranean and/or endemic flora, in a context of global warming. We note the presence of fourteen trigger species, including eight in common with the Babors and the Akfadou IPAs and four in common with the Djurdjura and the Medjerda ones. Besides, the investigated area has a significant number of plants important for Algeria. This presence of trigger species and/or plants important for the country allows to classifying the sector of Kéfrida as an extension of the Babors IPA

Systematics and phylogeography of the Mediterranean Helichysum pendulum complex (Compositae) inferred from nuclear and chloroplast DNA and morphometrics analyses

Multiple factors related to complex geomorphological and climatic history, in addition to biological factors such as hybridization, hinder the definition of some Mediterranean plant groups. The existence of controversial taxonomic treatments, the possible hybridization events involved, and its unknown evolutionary history, make the Helichrysum pendulum complex of H. sect. Stoechadina an ideal model to understand general processes of Mediterranean plant systematics and evolution. The mosaic range of the complex, which is distributed over several islands and continental areas in the western-central Mediterranean Basin, provides an opportunity to investigate how past connections and disconnections between landmasses may have determined the current geographic distribution of genetic variation in this area. The cpDNA region rpl32-trnL intergenic spacer and the nrDNA region ETS were sequenced for 1-8 individuals from each of the 44 populations sampled, covering all taxa and the whole geographic range of the complex. These individuals were analysed together with a broad sampling of the remaining members of sect. Stoechadina. In addition, detailed multivariate analyses of morphological characters were performed for the whole section and for the H. pendulum complex. Considering together distinctive genetic and morphological traits, our species concept is presented and discussed in a context of integrative taxonomy, and five species are recognized within the complex: H. errerae, H. melitense, H. pendulum, H. saxatile and H. valentinum. The first three species are recognizable by qualitative and quantitative morphological traits, and are genetically distinguishable from the rest as shown by the molecular markers analysed. The two last species are reported here to have a putative ancient hybrid origin and are also genetically distinguishable from the rest but morphologically recognisable only by quantitative characters. Phylogenetic relationships shown by nuclear and chloroplast markers, and an intermediate morphology between the two putative parental taxa, point to H. pendulum and H. italicum as the putative parental taxa for H. saxatile, and H. pendulum and H. stoechas as putative parental taxa for H. valentinum. In a discriminant analysis of the five species, 97.8% of all individuals were classified correctly. The high level of haplotype and ribotype diversity observed in North Africa indicates that this region is either the area of origin of the complex or a secondary contact zone. Our results suggest that the complex colonized several islands and migrated through the Gibraltar and Sicilian Straits during phases of low sea level, favoured by local dispersal events that promoted its gradual range expansion. The occurrence of the complex in the Balearic Islands, which have remained isolated even during low sea level phases, could be explained by stochastic long-distance dispersal events

Phylogeography of a Land Snail Suggests Trans-Mediterranean Neolithic Transport

Background: Fragmented distribution ranges of species with little active dispersal capacity raise the question about their place of origin and the processes and timing of either range fragmentation or dispersal. The peculiar distribution of the land snail Tudorella sulcata s. str. in Southern France, Sardinia and Algeria is such a challenging case. Methodology: Statistical phylogeographic analyses with mitochondrial COI and nuclear hsp70 haplotypes were used to answer the questions of the species' origin, sequence and timing of dispersal. The origin of the species was on Sardinia. Starting from there, a first expansion to Algeria and then to France took place. Abiotic and zoochorous dispersal could be excluded by considering the species' life style, leaving only anthropogenic translocation as parsimonious explanation. The geographic expansion could be dated to approximately 8,000 years before present with a 95% confidence interval of 10,000 to 3,000 years before present. Conclusions: This period coincides with the Neolithic expansion in the Western Mediterranean, suggesting a role of these settlers as vectors. Our findings thus propose that non-domesticated animals and plants may give hints on the direction and timing of early human expansion routes