Effects of Bamboo (Guadua spp.) Dominance on Germination and Soil Seed Bank Diversity of an Open Forest in Western Amazonia

Abstract The soil seed bank is essential for natural regeneration in tropical forests, but it was not known whether the predominance of bamboos of the genus Guadua in the forest understory influenced the composition and diversity of the soil seed bank and forest regeneration. For these reasons, we evaluated the soil seed bank in Western Amazon forests with and without dominant bamboo (Guadua spp.), comparing the density of emerged seedlings and floristic composition. The study was carried out in a forest fragment in the municipality of Senador Guiomard, Acre (10°04'S; 67°37'W. Altitude: 241 m), in forest typologies with and without dominant bamboo in the understory. In each typology, 20 samples of the soil seed bank were collected and germinated in an oven. Counting and identifying the emerged seedlings revealed a higher number of seedlings, density of emerged seedlings and species diversity in the samples from the forest without bamboo. The floristic similarity between the seed banks was low. In the forest with bamboo, the most common species were Trema micranthum, Cecropia sciadophylla and Alchorneopsis floribunda, while in the forest without bamboo it was Saccoloma sp.