Seed Banks in Savanna, Forest Fragments, and Continuous Forest Edges Differ in a Tropical Dry Forest in Madagascar

摘要: Rapid deforestation has fragmented habitat across the landscape of Madagascar. To determine effect fragmentation on seed banks and potential for forest regeneration, we sampled viability, density diversity in 40 plots 1 m2 three types: fragments, near edge continuous forest, deforested savanna a highly dry deciduous northwestern While species was not different between fragments edge, number animal-dispersed seeds significantly higher than this pattern driven by single, small-seeded species. In savanna, were absent from all but plots, indicating that regeneration is low these areas. Several pre- post-dispersal biotic abiotic factors, including variation predator communities effects could explain findings. Understanding extent to which dispersal influence landscapes critical as are sources expansion re-connectivity. Resume Le sort de graines dispersees peut etre altere en reponse la perte et d’ habitats, modifiant ainsi les banques semences du sol. Nous avons echantillonne viabilite, densite diversite des dans parcelles trois types d'habitats le paysage forestier feuillu, sec, fragmente nord-ouest Madagascar: (1) foret (2) bords rapproches ininterrompue, (3) savane deboisee. Notre objectif etait d’etablir l'effet cette sur semences, possibilite forestier. Nos resultats demontrent, bien que especes ne varie pas entre quantite par animaux est considerablement plus elevee premier type d'habitat deuxieme, cet effet grâce une seule espece [a petites graines]. Dans deboisee, absence complete ete notee tous parcelles, part trois. Plusieurs facteurs biotiques qu’ abiotiques, post-dispersion, sont impliques, y compris variations au sein communautes predateurs effets lisiere. Le potentiel paysages fragmentes repose meilleure comprehension nature l’etendue changements dispersion graines, resultantes semences. Ceci particulierement important Madagascar, ou forets se poursuit un rythme precipite, puisque ces essentielles l'expansion reconnexion forestiere.