Aim Tropical forests store 25% of global carbon and harbour 96% of the world's tree species, but it is not clear whether this high biodiversity matters for carbon storage. Few studies have teased apart the relative importance of forest attributes and environmental drivers for ecosystem functioning, and no such study exists for the tropics. Location Neotropics. Methods We relate aboveground biomass (AGB) to forest attributes (diversity and structure) and environmental drivers (annual rainfall and soil fertility) using data from 144,000 trees, 2050 forest plots and 59 forest sites. The sites span the complete latitudinal and climatic gradients in the lowland Neotropics, with rainfall ranging from 750 to 4350 mm year−1. Relationships were analysed within forest sites at scales of 0.1 and 1 ha and across forest sites along large‐scale environmental gradients. We used a structural equation model to test the hypothesis that species richness, forest structural attributes and environmental drivers have independent, positive effects on AGB. Results Across sites, AGB was most strongly driven by rainfall, followed by average tree stem diameter and rarefied species richness, which all had positive effects on AGB. Our indicator of soil fertility (cation exchange capacity) had a negligible effect on AGB, perhaps because we used a global soil database. Taxonomic forest attributes (i.e. species richness, rarefied richness and Shannon diversity) had the strongest relationships with AGB at small spatial scales, where an additional species can still make a difference in terms of niche complementarity, while structural forest attributes (i.e. tree density and tree size) had strong relationships with AGB at all spatial scales. Main conclusions Biodiversity has an independent, positive effect on AGB and ecosystem functioning, not only in relatively simple temperate systems but also in structurally complex hyperdiverse tropical forests. Biodiversity conservation should therefore be a key component of the UN Reducing Emissions from Deforestation and Degradation strategy.

The plants' answer to the top-bioclimate conditions is important for mapping occurrences and indications of preferential areas for the development of the forest species. This study aimed to georeference the natural occurrence of Taxibranco (Sclerolobium paniculatum Vogel) and Parica (Schizolobium parahyba var. amazonicum (Huber ex Ducke) Barneby) integrated with top-bioclimate information to indicate plantations for rehabilitation of degraded landscape. The data regarding natural occurrence of species was investigated in the literature, the herbaria of Embrapa Eastern Amazon and the Paraense Emilio Goeldi Museum and demonstrative units in the Eastern Amazon. Normal climates from thirty year series with spatial resolution 3 km x 3 km were specialized in Arcgis 9.3 and exported to TerraView 3.2, to create the cellular space for integration of variables in TerraME and to generate top-climate maps and species' natural occurrence. As the Taxi-branco occurs in upland and lowland it was observed that the species prefers areas of predominantly top bioclimate with water deficit between 150 to 250 mm, and elevations below 200 m altitude, next to the river, and the Parica in about 300 m altitude, and water deficit below 180 mm. The knowledge of these zones should enhance the degree of confidence on the areas indicated to the development of strategies for the genetic resources conservation and sustainable management of threatened tree species.

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Neste estudo foram avaliadas as mudanças estruturais dos fragmentos florestais superiores a 1km2 localizados na porção norte da área do Centro de Endemismo Belém (CEB). Os dados foram obtidos de imagens orbitais do satélite Landsat 5 e 8, dos anos de 1985 e 2018, e se aplicaram sete índices de análise da paisagem no sistema computacional FRAGSTATS v. 4.2. Foram considerados tamanho, forma e proximidade dos fragmentos. O resultado da análise temporal evidenciou que, nesse período, houve um aumento do número (quantidade) de fragmentos, redução do tamanho médio da área total dos mesmos, além da redução significativa da agregação, promovendo o aumento no nível de fragmentação que pode afetar a manutenção da biodiversidade local, pois se refere à diminuição da quantidade de área total de habitat na paisagem da área de estudo.

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