8 documents found, page 1 of 1
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...
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...
Seasonal drought limits tree species across the Neotropics
Esquivel-Muelbert, Adriane; Baker, Timothy R.; Dexter, Kyle Graham; Lewis, Simon L.; ter Steege, H.; Lopez-Gonzalez, Gabriela; Monteagudo-Mendoza, AbelWithin the tropics, the species richness of tree communities is strongly and positively associated with precipitation. Previous research has suggested that this macroecological pattern is driven by the negative effect of water-stress on the physiological processes of most tree species. This implies that the range limits of taxa are defined by their ability to occur under dry conditions, and thus in terms of spe...
Tree height integrated into pantropical forest biomass estimates
Feldpausch, Ted R.; Lloyd, Jon; Lewis, Simon L.; Brienen, Roel J.W.; Gloor, Manuel E.; Monteagudo-Mendoza, Abel; Lopez-Gonzalez, GabrielaAboveground tropical tree biomass and carbon storage estimates commonly ignore tree height (H). We estimate the effect of incorporating H on tropics-wide forest biomass estimates in 327 plots across four continents using 42 656 H and diameter measurements and harvested trees from 20 sites to answer the following questions: ; 1. What is the best H-model form and geographic unit to include in biomass models to mi...
Variation in stem mortality rates determines patterns of above-ground biomass i...
Johnson, Michelle O.; Galbraith, David R.; Gloor, Manuel E.; Deurwaerder, Hannes de; Guimberteau, Matthieu; Rammig, Anja; Thonicke, KirstenUnderstanding the processes that determine above-ground biomass (AGB) in Amazonian forests is important for predicting the sensitivity of these ecosystems to environmental change and for designing and evaluating dynamic global vegetation models (DGVMs). AGB is determined by inputs from woody productivity [woody net primary productivity (NPP)] and the rate at which carbon is lost through tree mortality. Here, we...
Phylogenetic diversity of Amazonian tree communities
Honorio Coronado, Euridice N.; Dexter, Kyle Graham; Pennington, R. Toby; Chave, Jérôme; Lewis, Simon L.; Alexiades, Miguel N.; Alvarez, EstebanAim: To examine variation in the phylogenetic diversity (PD) of tree communities across geographical and environmental gradients in Amazonia. Location: Two hundred and eighty-three c. 1 ha forest inventory plots from across Amazonia. Methods: We evaluated PD as the total phylogenetic branch length across species in each plot (PDss), the mean pairwise phylogenetic distance between species (MPD), the mean nearest...