A new Erica lusitanica Rudolphi heathland association to the Iberian south-west

As result of several field trips following doctoral research in Marianic-Monchiquensean Sector, we describe a new heathland named Lavandulo viridis-Ericetum lusitanici ass nova hoc loco (Genistion micrantho-anglicae, Rivas- Martínez 1979) as a thermomediterranean to lower mesomediterranean, upper dry to humid, schistose association. The analysis of 11 relevés, following Braun-Blanquet methodology shows the floristic identity of this new association as well as the chorological segregation of its area of occurrence. Finally, despite these communities already being relatively well known and although they are poor in species number, such heathlands show floristic singularity and own sinecology, with a large and distinct geographical area of distribution, so we emphasized its integration within Atlantic wet heaths priority habitat (⁄4020 – Annex B-I from Council Directive 92/43/EEC of 21 May 1992)

Approach to climatophilous vegetation series of Serra da Estrela (Portugal)

This work contains the study results of climatophilous vegetation series from Serra da Estrela, the highest mountain on the Portuguese mainland. Located in central-northern Portugal in the Estrelensean Sector (Carpetan-Leonese Subprovince), the Serra da Estrela has several bioclimatic stages, mainly resulting from slope and altitude ranges: mesomediterranean, submediterranean mesotemperate, supramediterranean, submediterranean supratemperate, and submediterranean orotemperate. In each of these belts are observed changes in plant communities that determine variations in terms of the vegetation series. The methodology was based on Dynamic-Catenal Phytosociology. The results show the presence of five climatophilous series; their structural characteristics and dynamics are described in this paper: 1. Lycopodio clavati–Junipereto nani S.; 2. Saxifrago spathularis–Betuleto celtibericae S.; 3. Holco mollis–Querco pyrenaicae S.; 4. Arbuto–Querco pyrenaicae cytisetoso grandiflori S.; e 5. Viburno tini–Querco roboris S

Caractéristiques structurales et écologiques des phytocénoses forestières de la forêt classée d’itchèdè (département du plateau, sud-est bénin)

Notre étude phytosociologique a été menée dans la forêt classée d’Itchèdè (6°59’-7°00’N et 2°37’-2°38’ E). Elle a pour objectif de mieux connaître la forêt pour un meilleur suivi de sa dynamique en vue d’asseoir à terme, une base fiable de son aménagement et de sa gestion durable. Nous avons utilisé l’approche synusiale intégrée pour identifier et caractériser les communautés végétales. La topographie et les sols ont été étudiés à travers la mesure des pentes, l’appréciation de la texture tactile à travers des profils texturaux effectués sur 50 cm de profondeur, la descriptionde profils pédologiques complétée par des analyses d’échantillons de sol au laboratoire. L’étude des paramètres dendrométriques et sylvicoles s’est faite à l’intérieur de placettes circulaires couvrant chacune 0,0314 ha pour les plantations forestières et 0,0615 ha pour la forêt naturelle.Les résultats ont révélé la présence de six phytocénoses dont quatre phytocénoses non pionnières de sous-bois. Les caractéristiques dendrométriques des phytocénoses permettent de déduire que la forêt naturelle d’Itchèdè est une formation secondaire assez dégradée mais relativement riche en sujets de grands diamètres en comparaison avec les autres forêts du Bénin.Mots-clés : phytosociologie synusiale, phytocénoses, stations forestières, Itchèdè, BéninThe main purpose of the phytosociological study in Itchèdè forest reserve (6°59’ to 7°00’ N and 2°37’ to 2°38’ E) was to contribute to the sustainable management of the forest. Phytosociological survey was done using the synusial approach. Soils and topography were studied through textural profiles appreciation in the first 50 cm of the soil, pedological profiles description and laboratory analysis. Dendrometric and sivicultural parameters were studied inside circular plots of 0.0314 ha for plantations and 0.0615 ha for natural forest. The study revealed the existence of six plant-communities including four non pioneer plant-communities were identified and described. Based on dendrometric parameters of the natural forest, we assume that Itchèdè forest reserve is a secondary degraded forest but somewhat rich in trees with high diameters in comparison with other natural forest in Benin

Dynamic-Catenal Phytosociology for evaluating vegetation

[EN] The conservation of nature is a problem that has concerned the scientific community for many years. Plants and plant communities play a main role in evaluation and land management studies, owing to their importance as natural and cultural resources. Several studies from the perspective of flora and vegetation have been carried out in the last fifty years (some of them directly related to Phytosociology). According to that, the Dynamic-Catenal Phytosociology must be considered as a very useful tool to evaluate the conservation status of vegetation and to establish suitable models for land management. The fundamental phytosociological concepts to take into account in the evaluation processes of the conservation status of vegetation are reviewed in this study

Managing the Flemish dunes: from eco-gardening to mechanical disturbances created by bulldozers

The ‘Conseil Général du Département du Nord’ is the manager of 480ha of Flemish dunes located at the far North of France. These spaces, initially preserved by the action of the ‘Communauté Urbaine de Dunkerque’ are now the property of the ‘Conservatoire de l’Espace Littoral et des Rivages Lacustres’. Characterised by an aelian dynamism and by the winter flooding of their damp depressions, these systems had represented a very high patrimonial richness before man, by these actions (the pumping of the aquifers, the parcelling out of dune massifs, the fixation of sand by plantations, the destruction of rabbits), reduced to nothing the natural expression of perturbations (storms, floods, important sandbanks) and made dune massifs become wastelands and low marshes and dry lawns disappear. The first step for preservation was the in extremis safeguard and the maintenance by secateurs (1989) then by motor scythes (1992) of micro-habitats with a high richness over a 2ha total surface lost in very important pre-forested systems. Rapidly, the objectives of preservation obliged us to put into practice the restoration of natural environments by stripping and clearing the ground (1994 and 1997). But these operations of a large scale (10ha) were always based on a ‘fixist’ and ‘museographical’ approach to the environment (the maintenance of a representative sample of habitats). The management which consists of stopping certain pioneer and post-pioneer stages of vegetation can in fact correspond to a counter-natural step as these dune systems make the proof of a very high dynamism and permanent evolution. Today the management of dune space is done by bulldozers: first the pre-forested vegetation is totally destructed (16ha in 2004) leaving systems of bare sand freely evolving and accepting their spontaneous wastelanding over more than 50% of their surfaces. The return to uncontrolled vegetal dynamism is only accepted if perturbations are periodically created in order to regularly produce the starting or reappearance conditions of the different series of vegetation. The last stage of our managing operations would consist, with a middle-term effect, in reducing the stability of the edging dune row and in favouring the development of wind passages with their devastation or saving effects on the dune we intend to preserve

Etude des groupements végétaux de la forêt classée d’Agrimey: application à l’identification et à la caractérisation des stations forestières

L’étude des groupements végétaux de la forêt classée d’Agrimey a pour but d’asseoir les bases d’un aménagement et d’une gestion durables des plantations forestières de ladite forêt. Cette étude intègre trois composantes intimement liées. L’étude phytosociologique de la végétation spontanée a eu lieu suivant l’approche synusiale intégrée. L’étude des facteurs écologiques (topographiques et pédologiques surtout) s’est faite à travers la mesure des pentes et des sondages à la tarière pédologique. L’étude des caractéristiques dendrométriques et sylvicoles des plantations forestières s’est faite par l’installation des placettes temporaires de 300 m2. Au total, quinze (15) synusies végétales ont été identifiées et intégrées en cinq (05) phytocénoses sur la base des relations spatio-temporelles : la phytocénose à Chromolaena odorata des milieux  ensoleillés, la phytocénose à Imperata cylindrica indica et Chromolaena odorata des milieux dégradés, la phytocénose à Reissantia indica et Uvaria chamae des sols ferrugineux tropicaux bien drainés, la phytocénose à Mallotus oppositifolius et Deinbollia pinnata des sols ferrugineux tropicaux et vertisols assez bien drainés et la phytocénose à Mitragyna inermis et Nauclea latifolia des sols hydromorphes. Ces phytocénoses sont corrélées avec la productivité des plantations forestières. L’étude de la dispersion des niveaux de productivité autour de la valeur moyenne a montré que la productivité est remarquablement homogène au sein de chaque phytocénose. Par ailleurs, l’analyse de la variance a mis en évidence un effet très hautement significatif des phytocénoses sur la productivité des plantations. On en déduit en toute logique que le biotope de chaque phytocénose représente une station forestière.Mots clés: Plantation forestière, phytosociologie, phyocénose, productivité, Bénin

Método fitossociológico de Braun-Blanquet ou clássico sigmatista (análise da vegetação).

A paisagem é um termo muito utilizado, quer na linguagem científica ou técnica, quer no dia-a-dia. Foi a partir do meado do séc. XIX, que a paisagem se tornou objecto de estudo científico, a par da concepção artística. Até a actualidade, ultrapassou várias etapas, numa trajectória irregular e divergente, nas quais se destaca: início no séc. XIX, com os naturalistas, geógrafos e ecologistas; primeira metade do séc. XX com os geógrafos e geobotânicos; após a 2ª Guerra Mundial, com os novos conhecimentos de botânica ecológica, geografia física, planeamento territorial e teoria geral dos ecossistemas e a partir dos anos 60, com a separação da escola da ecologia da paisagem e da paisagem integrada. Na concepção de paisagem, a vegetação é uma componente de grande importância, não só como elemento estético ou visual, mas também como objecto científico. Muitos autores que tentaram sistematizar a paisagem, referem que a vegetação é o melhor ponto de partida para delimitar as unidades homogéneas ou unidades de paisagem, do ponto de vista das associações ou agrupamentos vegetais. Na compilação da metodologia de Braun-Blanquet ou clássico sigmatista, recorreu-se a bibliografia variada, destacando as obras de Aguiar & Honrado (2001), Braun-Blanquet (1979), Diaz Gonzalez (1996), Foulcault (1986), Géhu & Rivas-Martínez (1981), Gillet et al. (1991), Guinochet (1973), Pavillard (1935) e Rivas-Martínez (1996), entre outros

Woody plant communities of Comoe-Leraba reserve: Characterisation and impact of soils on their distribution

The protected areas are worth great in vegetation conservation; this supported their interest in scientific research on the tools being able to be used for their sustainable management. The present study enters within the framework of a better knowledge of Comoé-Léraba reserve plants communities’ and the soils conditions which explained their distribution, in the aim to make better decisions for it conservation. The objective of the survey is to discriminate the plants communities in relation to soils’ physicals and chemicals parameters which control their distribution. Thus, 368 physociological plots have been done in the field by applying Braun-Blanquet (1932) method and then the plants communities’ package has been carried out in CANOCO software. In related to each ecosystem, 11 plants communities’ have been clearly defined, according the phytosociological statements (DCA). Among these communities four news syntaxons were determined based on previous studies in the same phytogeographical zones. Then their direct ordination (CCA) with soil’s (physical and chemical) parameters, shows that plants communities’ distribution is governed mainly by the water regulation on the ground and also its texture. The obtained results will certainly contribute to lay down a constant policy maker in biodiversity conservation. Lieux de refuge et de conservation de la végétation, les aires protégées sont des zones potentiellement diversifiées. Elles suscitent un grand intérêt pour la recherche en vue de découvrir des outils pouvant servir à leur gestion durable. La présente étude entre dans le cadre d’une meilleure connaissance des communautés végétales de la réserve de la Comoé-Léraba et des conditions édaphiques qui sous-tendent leur installation en vue de faciliter les prises de décisions entrant dans le cadre de sa conservation. Ainsi, l’objectif était de discriminer les groupements végétaux en relation avec les paramètres édaphiques qui gouvernent leur distribution. Sur le terrain, 368 relevés physociologiques ont été réalisés en appliquant la méthode de Braun Blanquet (1932) et l’individualisation des groupements végétaux a été réalisée grâce au logiciel CANOCO. L’analyse a permis de discriminer 11 groupements végétaux dont la classification syntaxonomique révèle quatre nouveaux taxons comparativement aux études réalisées dans les zones phytogéographiques similaires. L’ordination directe (CCA) intégrant les paramètres physiques et chimiques des sols, permet de considérer la texture et les paramètres hydriques des sols comme étant les plus efficients dans la distribution des groupements végétaux. Les résultats obtenus contribueront certainement à définir une politique soutenue de la conservation de la biodiversité