Near infrared spectroscopy facilitates rapid identification of both young and mature Amazonian tree species

<p>This study was developed to assess the potencial of the Near Infrared (FT-NIR) Spectroscopy to discrimination Amazon tree species. The species used in the study belong to the Burseraceae, genus Protium and Crepidospermum. The botanical material used was from herbarium specimens collected in Ducke Reserve from January to March 2013, and herbarium specimens that were collected from trees tagged at permanent plots belonging the BDFFP project over the past 35 years.  The herbarium specimens correspond to different ontogenetic stages: seedlings, juveniles and adults. The spectral readings are expressed by the values of absorbance between the wavenumbers 4000-10000 (cm-1) in the near infrared.</p

Results of discriminant analysis based on the average of 12 readings and the most informative wavelengths selected by stepwise modelling.

<p>Mean Ad+Ab, the average of 12 readings; Mean Ad. the average of the readings adaxial surface (Ad); Mean Ab, the average of the readings adaxial surface; Single Reading, a randomly selected reading. Hit percentage for each species and average percentage for models generated with each set of data are given.</p><p>Results of discriminant analysis based on the average of 12 readings and the most informative wavelengths selected by stepwise modelling.</p

Number of specimens used to obtain FT-NIR spectra.

<p>Number of specimens used to obtain FT-NIR spectra.</p

Results of discriminat analysis using the average of the readings and all wavelengths of the spectrum FT-NIR.

<p>Mean Ad +Ab, the average of 12 readings; Mean Ad, the average of the readings of the adaxial surface; Mean Ab, the average of the readings abaxial surface; Single reading, a randomly selected reading. Hit percentage for each species and average percentage for models generated with each data set.</p><p>Results of discriminat analysis using the average of the readings and all wavelengths of the spectrum FT-NIR.</p

Above-ground biomass of Neotropical secondary forests database

This database is the product of the 2ndFOR collaborative research network on secondary forests. The database contains aboveground biomass data (in Mg/ha) for 1334 secondary forest plots differing in time since abandonment. The plots belong to different chonosequence studies in the Neotropics. For a description of the database, see Poorter et al. 2016. Biomass resilience of Neotropical secondary forests. Nature doi:10.1038/nature16512

Unraveling Amazon tree community assembly using Maximum Information Entropy: a quantitative analysis of tropical forest ecology

In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain eight times more of local relative abundances than constraints based on directional selection for specific functional traits, although the latter does show clear signals of environmental dependency. These results provide a quantitative insight by inference from large-scale data using cross-disciplinary methods, furthering our understanding of ecological dynamics.</p