Site-to-site variation in species composition (β-diversity) generally increases from low- to high-diversity regions. Although biogeographical differences in community assembly mechanisms may explain this pattern, random sampling effects can create this pattern through differences in regional species pools. Here, we compared assembly mechanisms between spatially extensive networks of temperate and tropical forest plots with highly divergent species pools (46 vs. 607 species). After controlling for sampling effects, β-diversity of woody plants was similar and higher than expected by chance in both forests, reflecting strong intraspecific aggregation. However, different mechanisms appeared to explain aggregation in the two forests. In the temperate forest, aggregation reflected stronger environmental correlations, suggesting an important role for species-sorting (e.g. environmental filtering) processes, whereas in the tropics, aggregation reflected stronger spatial correlations, more likely reflecting dispersal limitation. We suggest that biogeographical differences in the relative importance of different community assembly mechanisms contribute to these striking gradients in global biodiversity.

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Pragmatic methods to assess the status of biodiversity at multiple scales are required to support conservation decision-making. At the intersection of several major biogeographic zones, Bolivia has extraordinary potential to develop a monitoring strategy aligned with the objectives of the Group on Earth Observations Biodiversity Observation Network (GEO BON). Bolivia, a GEO Observer since 2005, is already working on the adequacy of national earth observations towards the objectives of the Global Earth Observation System of Systems (GEOSS). However, biodiversity is still an underrepresented component in this initiative. The integration of biodiversity into Bolivia's GEO framework would confirm the need for a country level biodiversity monitoring strategy, fundamental to assess the progress towards the 2020 Aichi targets. Here we analyse and discuss two aspects of the process of developing such a strategy: (1) identification of taxonomic, temporal and spatial coverage of biodiversity data to detect both availability and gaps; and (2) evaluation of issues related to the acquisition, integration and analyses of multi-scale and multi-temporal biodiversity datasets. Our efforts resulted in the most comprehensive biodiversity database for the country of Bolivia, containing 648,534 records for 27,534 species referenced in time and space that account for 92.5% of the species previously reported for the country. We capitalise this information into recommendations for the implementation of the Bolivian Biodiversity Observation Network that will help ensure that biodiversity is sustained as the country continues on its path of development. Pragmatic methods to assess the status of biodiversity at multiple scales are required to support conservation decision-making. At the intersection of several major biogeographic zones, Bolivia has extraordinary potential to develop a monitoring strategy aligned with the objectives of the Group on Earth Observations Biodiversity Observation Network (GEO BON). Bolivia, a GEO Observer since 2005, is already working on the adequacy of national earth observations towards the objectives of the Global Earth Observation System of Systems (GEOSS). However, biodiversity is still an underrepresented component in this initiative. The integration of biodiversity into Bolivia's GEO framework would confirm the need for a country level biodiversity monitoring strategy, fundamental to assess the progress towards the 2020 Aichi targets. Here we analyse and discuss two aspects of the process of developing such a strategy: (1) identification of taxonomic, temporal and spatial coverage of biodiversity data to detect both availability and gaps; and (2) evaluation of issues related to the acquisition, integration and analyses of multi-scale and multi-temporal biodiversity datasets. Our efforts resulted in the most comprehensive biodiversity database for the country of Bolivia, containing 648,534 records *Corresponding author. Email: miguel.fernandez.trigoso@gmail.com . 16, Nos. 2-3, 86-98, http://...

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Both agronomic practices and spatial position can determine the assemblage of herbaceous species. We assess the dynamics and the contribution of these two aspects over time to the herb assemblages of different cocoa production systems. Braun-Blanquet surveys were performed over seven years in a long-term trial in Bolivia to compare different cocoa production systems: successional agroforestry (SA) with no external inputs, organic agroforestry (OA) and organic monoculture (OM), both including a leguminous perennial cover crop, conventional agroforestry (CA) and conventional monoculture (CM), where agrochemicals were applied. Using general linear models and multivariate analysis we found that assemblages were mainly driven by spatial position only at the beginning. After this, a very dynamic selection process related to the different management practices took place, which became more stable over the years. We observed a decline in species in both the CA and OA systems, due to the loss of heliophilous species and the low number of new species established in them. The OM presented the most conservative pattern, with the lowest number of new species and species lost, due to the presence of the cover crop. Both the most intensively managed system (CM) and the most diverse and least intensive one (SA) had the highest number of new species recorded over time, which led to highly specialized assemblages, with worldwide distributed and herbicide resistant species in the first case and secondary forest species, in the second. We conclude that the promotion of organic management and agroforestry systems, especially highly divers and successional agroforestry sytems would favour herb assemblages with high conservation value and prevent the establishment of globally distributed species.