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Soil-dwelling ants are the most diverse and abundant groups of animals in most terrestrial ecosystems. However, reliable techniques for assessing the abundance and diversity of ant communities with respect to land management remain poorly studied. The present study aimed to evaluate the efficiency of three trapping procedures (Pitfall trapping, quadrat sampling and baiting) in three habitats (urban, upland and littoral). A total of 169,934 ant workers belonging to 7 sub-families, 51 genera and 198 species were recorded in the three habitats. High species richness and abundance were recorded in upland habitats, compared to urban and littoral habitats. Similarly, contribution diversity approach based on species richness and Simpson’s index was high in upland habitats and low in littoral and urban habitats. Quadrat sampling was more efficient and reliable technique (138 species) than pitfall trapping (133 species) and baiting (126 species). Ant pitfall trapping was less efficient in urban and littoral habitats, but significantly effective in upland habitats. All techniques recorded more predominantly epigaeically foraging species than hypogaeically species. Ant community composition significantly varied among habitats, but no between sampling methods. These results highlight the influence of habitat traits on ant trapping success and indicate that sampling techniques used seem to be more suitable to sample a specific stratum, particularly the epigaeic ant fauna. Additional methods are therefore needed to increase the likelihood of recording hidden ant fauna and obtaining an adequate impression of the local ant fauna. Key words: sampling techniques, ants, epigaeic, hypogaeic, land management, Camer

Macrocyclic diarylheptanoids are intriguing and promising due to both their architectural features and biological properties. In this context, the objective of this thesis is to develop a new approach to prepare this appealing family of compounds. In the one hand, we envisioned synthetizing myricanol, a strained 13-membered meta,meta-diarylheptanoid, through a Suzuki-Miyaura coupling and a ring-closing metathesis. This pathway led to the unintended formation of 26-membered head-to-tail dimers as a result of the actual ring strain. In the other hand, we describe herein the first, direct, rapid and versatile route to access the ortho,meta-diarylheptanoids family via a ring-closing metathesis strategy. Hence, we applied this method to the synthesis of actinidione, a natural product bearing a benzoquinone motif, in 14 steps with an overall yield of 18% and a high degree of ideality in the choice of the synthesis strategy., Les diarylheptanoïdes macrocycliques possèdent des caractéristiques structurelles intrigantes et des propriétés biologiques prometteuses. Dans ce contexte, l’objectif de cette thèse consiste à développer une nouvelle voie de préparation pour cette attrayante famille de composés. Dans une première partie, nous avons envisagé de synthétiser le myricanol, un méta, méta-diarylheptanoïde tendu à 13 chaînons, par le biais d’un couplage de Suzuki-Miyaura et d’une métathèse cyclisante. Cette voie d’accès a conduit à la formation fortuite de dimères tête-queue à 26 chaînons du fait de la tension de cycle existante. Dans une deuxième partie, nous avons décrit la première voie d’accès directe, rapide et versatile à la famille des ortho,méta-diarylheptanoïdes via une stratégie de métathèse cyclisante. Ainsi, nous avons appliqué cette méthode à la synthèse de l’actinidione, produit naturel contenant un motif benzoquinone, en 14 étapes avec un rendement global de 18% et un haut degré d’idéalité dans le choix de la stratégie de synthèse.

Massé Paul. Le dessèchement des marais du Bas-Médoc. In: Revue historique de Bordeaux et du département de la Gironde, tome 6 n°1, 1957. pp. 25-68.