The Influence of Ecosystem and Phylogeny on Tropical Tree Crown Size and Shape

The sizes and shapes of tree crowns are of fundamental importance in ecology, yet understanding the forces that determine them remains elusive. A cardinal question facing ecologists is the degree to which general and non-specific versus ecological and context-dependent processes are responsible for shaping tree crowns. Here, we test this question for the first time across diverse tropical ecosystems. Using trees from 20 plots varying in elevation, precipitation, and ecosystem type (savanna-forest transitions) across the paleo- and neo-tropics, we test the relationship between crown dimensions and tree size. By analyzing these scaling relationships across environmental gradients, biogeographic regions, and phylogenetic distance, we extend Metabolic Scaling Theory (MST) predictions to include how local selective pressures shape variation in crown dimensions. Across all sites, we find strong agreement between mean trends and MST predictions for the scaling of crown size and shape, but large variation around the mean. While MST explained approximately half of the observed variation in tree crown dimensions, we find that local, ecosystem, and phylogenetic predictors account for the half of the residual variation. Crown scaling does not change significantly across regions, but does change across ecosystem types, where savanna tree crowns grow more quickly with tree size than forest tree crowns. Crowns of legumes were wider and larger than those of other taxa. Thus, while MST can accurately describe the central tendency of tree crown size, local ecological conditions and evolutionary history appear to modify the scaling of crown shape. Importantly, our extension of MST incorporating these differences accounts for the mechanisms driving variation in the scaling of crown dimensions across the tropics. These results are critical when scaling the function of individual trees to larger spatial scales or incorporating the size and shape of tree crowns in global biogeochemical models.

[1]  M. Disney,et al.  Time for a Plant Structural Economics Spectrum , 2019, Front. For. Glob. Change.

[2]  Jérôme Chave,et al.  Improving plant allometry by fusing forest models and remote sensing. , 2019, The New phytologist.

[3]  Edward T. A. Mitchard,et al.  Extending the baseline of tropical dry forest loss in Ghana (1984–2015) reveals drivers of major deforestation inside a protected area , 2018 .

[4]  D. W. MacFarlane,et al.  Neighbour effects on tree architecture: functional trade-offs balancing crown competitiveness with wind resistance , 2017 .

[5]  R. Chazdon,et al.  Nitrogen-fixing trees inhibit growth of regenerating Costa Rican rainforests , 2017, Proceedings of the National Academy of Sciences.

[6]  O. Phillips,et al.  The variation of productivity and its allocation along a tropical elevation gradient: a whole carbon budget perspective. , 2017, The New phytologist.

[7]  R. L. Rodríguez,et al.  Ordinary least squares regression is indicated for studies of allometry , 2017, Journal of evolutionary biology.

[8]  M. Andrews,et al.  Specificity in Legume-Rhizobia Symbioses , 2016, International journal of molecular sciences.

[9]  Gregory P. Asner,et al.  GEMTraits: A database and R package for accessing and analyzing plant functional traits from the Global Ecosystems Monitoring Network , 2017 .

[10]  P. Couteron,et al.  Contrasted allometries between stem diameter, crown area, and tree height in five tropical biogeographic areas , 2016, Trees.

[11]  Roberta E. Martin,et al.  Plant leaf wax biomarkers capture gradients in hydrogen isotopes of precipitation from the Andes and Amazon. , 2016 .

[12]  Stephanie A. Bohlman,et al.  Dominance of the suppressed: Power-law size structure in tropical forests , 2016, Science.

[13]  A. Huth,et al.  The structure of tropical forests and sphere packings , 2015, Proceedings of the National Academy of Sciences.

[14]  Hendrik Poorter,et al.  How does biomass distribution change with size and differ among species? An analysis for 1200 plant species from five continents , 2015, The New phytologist.

[15]  Marcos Longo,et al.  Linking canopy leaf area and light environments with tree size distributions to explain Amazon forest demography. , 2015, Ecology letters.

[16]  Henrik Singmann,et al.  afex – Analysis of Factorial EXperiments , 2015 .

[17]  Matheus Alves Zanellaa,et al.  The role of soil , 2015 .

[18]  Glenn R. Moncrieff,et al.  Contrasting architecture of key African and Australian savanna tree taxa drives intercontinental structural divergence , 2014 .

[19]  M. Loreau,et al.  Tropical tree diversity enhances light capture through crown plasticity and spatial and temporal niche differences , 2014 .

[20]  Paul C. Johnson.  Extension of Nakagawa & Schielzeth's R2GLMM to random slopes models , 2014, Methods in ecology and evolution.

[21]  D. Bates,et al.  Fitting Linear Mixed-Effects Models Using lme4 , 2014, 1406.5823.

[22]  O. Phillips,et al.  Disequilibrium and hyperdynamic tree turnover at the forest–cerrado transition zone in southern Amazonia , 2014 .

[23]  R Core Team,et al.  R: A language and environment for statistical computing. , 2014 .

[24]  Roberta E. Martin,et al.  Landscape-scale changes in forest structure and functional traits along an Andes-to-Amazon elevation gradient , 2013 .

[25]  Helene C. Muller-Landau,et al.  Measuring tree height: a quantitative comparison of two common field methods in a moist tropical forest , 2013 .

[26]  Roberta E. Martin,et al.  High-fidelity national carbon mapping for resource management and REDD+ , 2013, Carbon Balance and Management.

[27]  Crown allometries are less responsive than stem allometry to tree size and habitat variations in an Indian monsoon forest , 2013, Trees.

[28]  H. Pretzsch,et al.  Morphological plasticity of European beech (Fagus sylvatica L.) in pure and mixed-species stands , 2013 .

[29]  Markus Gastauer,et al.  Avoiding inaccuracies in tree calibration and phylogenetic community analysis using Phylocom 4.2 , 2013, Ecol. Informatics.

[30]  A. Tredennick,et al.  Allometric Convergence in Savanna Trees and Implications for the Use of Plant Scaling Models in Variable Ecosystems , 2013, PloS one.

[31]  Shinichi Nakagawa,et al.  A general and simple method for obtaining R2 from generalized linear mixed‐effects models , 2013 .

[32]  Michael J. Crawley.  The R Book: Crawley/The R Book , 2012 .

[33]  D. A. King,et al.  What controls tropical forest architecture: testing environmental, structural and floristic drivers , 2012 .

[34]  Rampal S Etienne,et al.  Testing the metabolic theory of ecology. , 2012, Ecology letters.

[35]  Sara Taskinen,et al.  smatr 3– an R package for estimation and inference about allometric lines , 2012 .

[36]  Liam J. Revell,et al.  phytools: an R package for phylogenetic comparative biology (and other things) , 2012 .

[37]  B. Enquist,et al.  Land Plants: New Theoretical Directions and Empirical Prospects , 2012 .

[38]  Tree shape plasticity in relation to crown exposure , 2012, Trees.

[39]  H. Pretzsch,et al.  Evidence of variant intra- and interspecific scaling of tree crown structure and relevance for allometric theory , 2012, Oecologia.

[40]  L. Poorter,et al.  Tree architecture and life‐history strategies across 200 co‐occurring tropical tree species , 2011 .

[41]  D. Coomes,et al.  Moving on from Metabolic Scaling Theory: hierarchical models of tree growth and asymmetric competition for light , 2011 .

[42]  Response to Coomes & Allen (2009) ‘Testing the metabolic scaling theory of tree growth’ , 2011 .

[43]  Sassan Saatchi,et al.  Introduction: Elevation gradients in the tropics: laboratories for ecosystem ecology and global change research , 2010 .

[44]  Luiz E. O. C. Aragão,et al.  Net primary productivity allocation and cycling of carbon along a tropical forest elevational transect in the Peruvian Andes , 2010 .

[45]  J. Weitz,et al.  The metabolic theory of ecology: prospects and challenges for plant biology. , 2010, The New phytologist.

[46]  D. A. King,et al.  Height-diameter allometry of tropical forest trees , 2010 .

[47]  M. Ilman,et al.  Net primary productivity allocation and cycling of carbon along a tropical forest elevational transect in the , 2010 .

[48]  R. Valentini,et al.  The role of soil in storing carbon in tropical rainforests: the case of Ankasa Park, Ghana , 2010, Plant and Soil.

[49]  David A. Coomes,et al.  Testing the Metabolic Scaling Theory of tree growth , 2009 .

[50]  Ken E. Giller,et al.  Are the rates of photosynthesis stimulated by the carbon sink strength of rhizobial and arbuscular mycorrhizal symbioses , 2009 .

[51]  Geoffrey B. West,et al.  A general quantitative theory of forest structure and dynamics , 2009, Proceedings of the National Academy of Sciences.

[52]  James H Brown,et al.  Extensions and evaluations of a general quantitative theory of forest structure and dynamics , 2009, Proceedings of the National Academy of Sciences.

[53]  Mollie E. Brooks,et al.  Generalized linear mixed models: a practical guide for ecology and evolution. , 2009, Trends in ecology & evolution.

[54]  David C. Tank,et al.  An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: , 2009 .

[55]  Campbell O. Webb,et al.  Bioinformatics Applications Note Phylocom: Software for the Analysis of Phylogenetic Community Structure and Trait Evolution , 2022 .

[56]  Eric J. Deeds,et al.  Sizing Up Allometric Scaling Theory , 2008, PLoS Comput. Biol..

[57]  L. Revell,et al.  Phylogenetic signal, evolutionary process, and rate. , 2008, Systematic biology.

[58]  Philip M. Fearnside,et al.  Tree height in Brazil's 'arc of deforestation' : Shorter trees in south and southwest Amazonia imply lower biomass , 2008 .

[59]  R. Wunderlin.  The Leguminosae: A source book of characteristics, uses, and nodulation , 1982, Economic Botany.

[60]  J. Slavíková.  Tropical trees and forests. An architectural analysis , 1980, Biologia Plantarum.

[61]  Drew W. Purves,et al.  Crown Plasticity and Competition for Canopy Space: A New Spatially Implicit Model Parameterized for 250 North American Tree Species , 2007, PloS one.

[62]  Charles A Price,et al.  A general model for allometric covariation in botanical form and function , 2007, Proceedings of the National Academy of Sciences.

[63]  T. Thomson,et al.  The Structure and Life of Forest Trees , 2007 .

[64]  Frans Bongers,et al.  Architecture of 54 moist-forest tree species: traits, trade-offs, and functional groups. , 2006, Ecology.

[65]  Stephanie A. Bohlman,et al.  Testing metabolic ecology theory for allometric scaling of tree size, growth and mortality in tropical forests. , 2006, Ecology letters.

[66]  M. Westoby,et al.  Bivariate line‐fitting methods for allometry , 2006, Biological reviews of the Cambridge Philosophical Society.

[67]  B. Junior,et al.  Comparação da vegetação arbórea e características edáficas de um cerradão e um cerrado sensu stricto em áreas adjacentes sobre solo distrófico no leste de Mato Grosso, Brasil , 2005 .

[68]  Raffaella Barone,et al.  General Model , 2005, Encyclopedia of Biometrics.

[69]  Sean C. Thomas,et al.  The worldwide leaf economics spectrum , 2004, Nature.

[70]  David King,et al.  Tree dimensions: Maximizing the rate of height growth in dense stands , 2004, Oecologia.

[71]  W. Bond,et al.  Growing tall vs growing wide: tree architecture and allometry of Acacia karroo in forest, savanna, and arid environments , 2003 .

[72]  James H. Brown,et al.  A general model for the structure and allometry of plant vascular systems , 1999, Nature.

[73]  G. Hutcheson.  Ordinary Least-Squares Regression , 1999 .

[74]  D. A. King.  Influence of leaf size on tree architecture: first branch height and crown dimensions in tropical rain forest trees , 1998, Trees.

[75]  F. Bongers,et al.  Ontogenetic changes in size, allometry, and mechanical design of tropical rain forest trees. , 1998, American journal of botany.

[76]  T. Kuuluvainen,et al.  Structure and asymmetry of tree crowns in relation to local competition in a natural mature Scots pine forest , 1997 .

[77]  James H. Brown,et al.  A General Model for the Origin of Allometric Scaling Laws in Biology , 1997, Science.

[78]  Koichi Takahashi.  Plastic Response of Crown Architecture to Crowding in Understorey Trees of Two Co-dominating Conifers , 1996 .

[79]  D. A. King,et al.  Allometry and life history of tropical trees , 1996, Journal of Tropical Ecology.

[80]  K. Niklas.  Size-dependent Allometry of Tree Height, Diameter and Trunk-taper , 1995 .

[81]  E. Moran.  Response to Coomes , 1992 .

[82]  Heinz-Otto Peitgen,et al.  The science of fractal images , 2011 .

[83]  Richard F. Voss,et al.  Fractals in nature: from characterization to simulation , 1988 .

[84]  James N. Long,et al.  Validity of Constant-Stress and Elastic-Instability Principles of Stem Formation in Pinus contorta and Trifolium pratense , 1986 .

[85]  Y. Iwasa,et al.  Tree height and crown shape, as results of competitive games , 1985 .

[86]  T. Givnish.  Leaf and Canopy Adaptations in Tropical Forests , 1984 .

[87]  H. Mooney,et al.  Physiological ecology of plants of the wet tropics , 1984, Tasks for vegetation Science.

[88]  David E. Hibbs,et al.  PLASTICITY OF TREE ARCHITECTURE: SPECIFIC AND ECOLOGICAL VARIATIONS FOUND IN AUBREVILLE'S MODEL , 1982 .

[89]  O. Loucks,et al.  The theory of tree bole and branch form , 1978, Radiation and environmental biophysics.

[90]  Prof. Dr. Francis Hallé,et al.  Tropical Trees and Forests , 1978, Springer Berlin Heidelberg.

[91]  T. McMahon,et al.  Tree structures: deducing the principle of mechanical design. , 1976, Journal of theoretical biology.

[92]  H. S. Horn.  The adaptive geometry of trees , 1971 .

[93]  P. Larson.  Stem Form Development of Forest Trees , 1963 .

[94]  M. Kleiber.  Body size and metabolism , 1932 .