RESUMO
The forests of western Amazonia are among the most diverse tree communities on Earth, yet this exceptional diversity is distributed highly unevenly within and among communities. In particular, a small number of dominant species account for the majority of individuals, whereas the large majority of species are locally and regionally extremely scarce. By definition, dominant species contribute little to local species richness (alpha diversity), yet the importance of dominant species in structuring patterns of spatial floristic turnover (beta diversity) has not been investigated. Here, using a network of 207 forest inventory plots, we explore the role of dominant species in determining regional patterns of beta diversity (community-level floristic turnover and distance-decay relationships) across a range of habitat types in northern lowland Peru. Of the 2,031 recorded species in our data set, only 99 of them accounted for 50% of individuals. Using these 99 species, it was possible to reconstruct the overall features of regional beta diversity patterns, including the location and dispersion of habitat types in multivariate space, and distance-decay relationships. In fact, our analysis demonstrated that regional patterns of beta diversity were better maintained by the 99 dominant species than by the 1,932 others, whether quantified using species-abundance data or species presence-absence data. Our results reveal that dominant species are normally common only in a single forest type. Therefore, dominant species play a key role in structuring western Amazonian tree communities, which in turn has important implications, both practically for designing effective protected areas, and more generally for understanding the determinants of beta diversity patterns.
Assuntos
Biodiversidade , Árvores , Ecossistema , Florestas , Peru , Clima TropicalRESUMO
El objetivo del trabajo fue determinar la influencia de un programa educativo sobre manejo sostenible de la biodiversidad en el aprendizaje y cambio de actitud de 54 estudiantes del tercero, cuarto y quinto de secundaria. Se utilizó la investigación aplicada. El diseño corresponde a una investigación cuasi experimental. Se manejó el método de enseñanza teórico-practico, basado en un programa educativo estructurado en talleres de aprendizaje y motivaciones al cambio de actitud. Se logró la mejora de los conocimientos en el 96% de los estudiantes. Se alcanzaron resultados mayores en el nivel 2 (logro) que fue del 65% en las tareas de la biodiversidad, cercos vivos, recuperación de suelos degradados, crianza de especies silvestres y agricultura orgánica. El 61% de los participantes consiguió una actitud favorable hacia el manejo sostenible de la biodiversidad.
The objetive of this work was to determine the influence of an educative program on sustainable management of biodiversity to develop learning and change of attitude capacities of 54 students of the third, fourth and fifth levels of secondary. Applied research was used. The design corresponds to an investigation quasi experimental. the method of practical theoretical education ws used, based in an educative program structured in learning workshops and motivation to the change of attitude. The results obtained were the improvement of knowledge in 96% of the students. The main results were in level 2 (target) of 65% in biodiversity activities, wind breaks, recovery of degrades soils, raising of wild species and organic agriculture. The 61% of the participants attained a favourable attitude towards sustainable management of biodiversity.
