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Variations in Amazon forest productivity correlated with foliar nutrients and m...
Mercado, Lina; Patiño, Sandra; null, Tomas; Fyllas, Nikolaos M.; Weedon, Graham P.; Sitch, Stephen A.; Quesada, Carlos Alberto; Phillips, Oliver L.The rate of above-ground woody biomass production, WP, in some western Amazon forests exceeds those in the east by a factor of 2 or more. Underlying causes may include climate, soil nutrient limitations and species composition. In this modelling paper, we explore the implications of allowing key nutrients such as N and P to constrain the photosynthesis of Amazon forests, and also we examine the relationship bet...
Competition influences tree growth, but not mortality, across environmental gra...
Rozendaal, Danaë M.A.; Phillips, Oliver L.; Lewis, Simon L.; Affum-Baffoe, Kofi; Alvarez, Esteban; Andrade, Ana C.S.; Aragao, L. E.O.C.Competition among trees is an important driver of community structure and dynamics in tropical forests. Neighboring trees may impact an individual tree’s growth rate and probability of mortality, but large-scale geographic and environmental variation in these competitive effects has yet to be evaluated across the tropical forest biome. We quantified effects of competition on tree-level basal area growth and mor...
Ecosystem heterogeneity determines the ecological resilience of the Amazon to c...
Levine, Naomi Marcil; Zhang, Ke; Longo, Marcos; Baccini, Alessandro; Phillips, Oliver L.; Lewis, Simon L.; Alvarez, EstebanAmazon forests, which store ∼50% of tropical forest carbon and play a vital role in global water, energy, and carbon cycling, are predicted to experience both longer and more intense dry seasons by the end of the 21st century. However, the climate sensitivity of this ecosystem remains uncertain: several studies have predicted large-scale dieback of the Amazon, whereas several more recent studies predict that th...
Do species traits determine patterns of wood production in Amazonian forests?
Baker, Timothy R.; Phillips, Oliver L.; Laurance, William F.; Pitman, Nigel C.A.; Almeida, Samuel Miranda; Arroyo, Luzmila P.; Di Fiore, AnthonyUnderstanding the relationships between plant traits and ecosystem properties at large spatial scales is important for predicting how compositional change will affect carbon cycling in tropical forests. In this study, we examine the relationships between species wood density, maximum height and above-ground, coarse wood production of trees ≥10 cm diameter (CWP) for 60 Amazonian forest plots. Average species max...
Biased-corrected richness estimates for the Amazonian tree flora
ter Steege, H.; Prado, Paulo I.; Lima, Renato A.Fde; Pos, Edwin T.; Coelho, Luiz Souza de; Lima Filho, Diógenes de Andrade; Salomão, Rafael PaivaAmazonian forests are extraordinarily diverse, but the estimated species richness is very much debated. Here, we apply an ensemble of parametric estimators and a novel technique that includes conspecific spatial aggregation to an extended database of forest plots with up-to-date taxonomy. We show that the species abundance distribution of Amazonia is best approximated by a logseries with aggregated individuals,...
Evolutionary heritage influences amazon tree ecology
Souza, Fernanda Coelho de; Dexter, Kyle Graham; Phillips, Oliver L.; Brienen, Roel J.W.; Chave, Jérôme; Galbraith, David R.; Lopez-Gonzalez, GabrielaLineages tend to retain ecological characteristics of their ancestors through time. However, for some traits, selection during evolutionary history may have also played a role in determining trait values. To address the relative importance of these processes requires large-scale quantification of traits and evolutionary relationships among species. The Amazonian tree flora comprises a high diversity of angiospe...
Basin-wide variations in Amazon forest structure and function are mediated by b...
Quesada, Carlos Alberto; Phillips, Oliver L.; Schwarz, Michael; Czimczik, Claudia I.; Baker, Timothy R.; Patiño, Sandra; Fyllas, Nikolaos M.Forest structure and dynamics vary across the Amazon Basin in an east-west gradient coincident with variations in soil fertility and geology. This has resulted in the hypothesis that soil fertility may play an important role in explaining Basin-wide variations in forest biomass, growth and stem turnover rates. Soil samples were collected in a total of 59 different forest plots across the Amazon Basin and analys...
Improving simulated Amazon forest biomass and productivity by including spatial...
Castanho, Andrea Dde Almeida; Coe, Michael T.; Costa, Marcos Heil; Malhi, Yadvinder Singh; Galbraith, David R.; Quesada, Carlos AlbertoDynamic vegetation models forced with spatially homogeneous biophysical parameters are capable of producing average productivity and biomass values for the Amazon basin forest biome that are close to the observed estimates, but these models are unable to reproduce observed spatial variability. Recent observational studies have shown substantial regional spatial variability of above-ground productivity and bioma...
Individual-based modeling of amazon forests suggests that climate controls prod...
Fauset, Sophie; Gloor, Manuel U.; Fyllas, Nikolaos M.; Phillips, Oliver L.; Asner, Gregory P.; Baker, Timothy R.; Patrick Bentley, LisaClimate, species composition, and soils are thought to control carbon cycling and forest structure in Amazonian forests. Here, we add a demographics scheme (tree recruitment, growth, and mortality) to a recently developed non-demographic model—the Trait-based Forest Simulator (TFS)—to explore the roles of climate and plant traits in controlling forest productivity and structure. We compared two sites with diffe...
Spatial distribution and functional significance of leaf lamina shape in Amazon...
Malhado, Ana Cláudia Mendes; Whittaker, Robert J.; Malhi, Yadvinder Singh; Ladle, Richard James; ter Steege, H.; Butt, Nathalie; Aragao, L. E.O.C.Leaves in tropical forests come in an enormous variety of sizes and shapes, each of which can be ultimately viewed as an adaptation to the complex problem of optimising the capture of light for photosynthesis. However, the fact that many different shape "strategies" coexist within a habitat demonstrate that there are many other intrinsic and extrinsic factors involved, such as the differential investment in sup...