The role of environmental filtering, geographic distance and dispersal barriers in shaping the turnover of plant and animal species in Amazonia

To determine the effect of rivers, environmental conditions, and isolation by distance on the distribution of species in Amazonia. Location: Brazilian Amazonia. Time period: Current. Major taxa studied: Birds, fishes, bats, ants, termites, butterflies, ferns + lycophytes, gingers and palms. We compiled a unique dataset of biotic and abiotic information from 822 plots spread over the Brazilian Amazon. We evaluated the effects of environment, geographic distance and dispersal barriers (rivers) on assemblage composition of animal and plant taxa using multivariate techniques and distance- and raw-data-based regression approaches. Environmental variables (soil/water), geographic distance, and rivers were associated with the distribution of most taxa. The wide and relatively old Amazon River tended to determine differences in community composition for most biological groups. Despite this association, environment and geographic distance were generally more important than rivers in explaining the changes in species composition. The results from multi-taxa comparisons suggest that variation in community composition in Amazonia reflects both dispersal limitation (isolation by distance or by large rivers) and the adaptation of species to local environmental conditions. Larger and older river barriers influenced the distribution of species. However, in general this effect is weaker than the effects of environmental gradients or geographical distance at broad scales in Amazonia, but the relative importance of each of these processes varies among biological groups

A reserva de desenvolvimento sustentável Mamirauá

AS UNIDADES de conservação ainda são um dos instrumentos mais eficientes na promoção da proteção e conservação da biodiversidade na Amazônia. As unidades de uso sustentável têm se mostrado cada vez mais importantes no cenário atual. Dentre os modelos propostos hoje para criação e gestão destas unidades, o Modelo de Reservas de Desenvolvimento Sustentável mostra-se viável e bastante bem-sucedido. Neste trabalho são apresentados os aspectos mais centrais da formulação deste modelo e exemplos oriundos do seu principal representante, a Reserva de Desenvolvimento Sustentável Mamirauá (RDSM), além de considerações acerca do sucesso e validação desse modelo por meio de sua replicação para outras áreas na Amazônia.<br>PROTECTED areas are still one of the most effective tools to promote bio-diversity protection and conservation in the Amazon. The importance of protected areas of sustainable use in the present scenario is increasing. Among the proposed conservation models for protected areas of sustainable use, the Sustainable Development Reserve Model is not only viable, but extremely successful. In the present paper the main aspects of such model are presented, with some illustration from it most well known representative, the Mamirauá Sustainable Development Reserve (MSDR), and with some discussion regarding the success and validation of the model through its replication for other sites in the Amazon