Landscape Regeneration by Seeds and Successional Pathways to Restore Fragile Tropandean Slopelands

Abstract

Although land abandonment in the equatorial Andes is a process that complicates the mosaic of land uses in Tropandean landscapes, in some cases land abandonment further contributes to the process of degradation. This includes not only soil but also the species composition and community structure of montane forest patches and, where succession fails, recalcitrant pasture grasses. In order to examine failed succession, studies were undertaken on the lack of seed input, the ability of seed dispersers, the efficacy of avian roosting from perches, the removal of seeds, germination from seeded scats, seedlings among the tussock grasses, and the recruitment of saplings of montane forest trees. It is suggested that regeneration by seeding may be possible only if proactive removal techniques of the aerial tillers of grass species and their extensive root mass is eliminated. However, pasture conversion to forest using Psidium guajaba as pioneer tree to enhance dispersal outwards from the forest edge, coupled with seasonally-driven seed rain episodes, is a posteriori. Land-use and land-clearing patterns dictate the outcome of the regenerating phenosystem. This means that policies and practices of montane forest clearing must include treefall 'survivors' to enhance frugivory, to provide shade and regeneration of interspersed patches, and to stimulate dispersal for rapid initiation of ecological succession. RESUME Rigindration du paysage par ensemencement et voies de succession pour la restauration des sols pentusfragiles des Andes tropicales. Bien que l'abandon des terres dans les Andes equatoriales constitue un processus compliquant la mosaique d'exploitation des terres dans les Andes tropicales, il contribue dans certains cas au processus de degradation. Ce processus n'affecte pas seulement le sol, mais