Neotropical forests are extremely diverse ecosystems, listed within the biological hotspots of our planet. However, species from these forests are threatened by diverse anthropogenic activities. Small dung beetles (Scarabaeidae, Aphodiinae) assemblages were studied within different habitats of the Brazilian Amazon. The monitored habitats encompassed the main gradients of disturbance, from pristine to highly anthropogenic situations, with the aim of supporting their use as indicators of neotropical forests' ecological status. Additionally, seasonal patterns and bait attractiveness were evaluated in the scope of more effective monitoring studies. Our main results demonstrate that the diversity and distribution of small dung beetles along disturbance gradients, represented by the monitored locations, is associated with particular habitats within the forest landscape. Although spatially and temporally restricted, the results of this study highlight the potential of using small dung beetles, due to their sensitivity and habitat specificity, as ecological indicators for assessing the extent of disturbance in neotropical forest landscapes. We also suggest specific techniques and periods to be used in order to increase captures of small dung beetles within the different habitats.

Considering the present ecological crisis, land use-biodiversity relationships have become a major topic in landscape planning, ecosystem management and ecological restoration. In this scope, consistent patterns of outstanding biodiversity have been identified in agroforestry systems within diverse biogeographic regions and types of management. Empirical work has revealed that agroforestry higher structural complexity, when compared with current simplified agricultural systems, might be partially responsible for the observed patterns. The recently developed Habitat Amount Hypothesis predicts diversity for a local habitat patch, from the amount of the same habitat within the local landscape. We have expanded the previous hypothesis to the landscape level, computing the influence of the dominant land uses on the diversity of coexisting guilds. As a case study, we have considered archetypal landscapes dominated (or co-dominated) by crops or trees, which were compared using normalized diversities. The results obtained show that agroforestry systems substantially increase functional diversity and overall biodiversity within landscapes. We highlight that the normalized values should be parametrized to real conditions where the type of crop, tree and agroecological management will make a difference. Most importantly, our findings provide additional evidence that agroforestry has a critical role in enhancing biodiversity in agricultural landscapes and, in this way, should be regarded as a priority measure in European Agri-environmental funding schemes.

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