Tree height–diameter allometry across the United States

• Published in: Ecology and evolution Vol. 5; no. 6; pp. 1193 - 1204
• Main Authors: Hulshof, Catherine M., Swenson, Nathan G., Weiser, Michael D.
• Format: Journal Article
• Language: English
• Published: England John Wiley & Sons, Inc 01.03.2015; BlackWell Publishing Ltd
• Subjects: Allometry; angiosperm; Angiosperms; Carbon sequestration; Climate models; Competition; Ecosystem structure; Ecosystems; Environmental conditions; Forest Inventory and Analysis National Program; Forests; Functional groups; gymnosperm; Gymnosperms; Hydraulics; Life history; Light; Original Research; Phylogeny; Plant species; Precipitation; Scaling; Shade; Temperature; Temperature effects; Trees; Variation; United States > US; gymnosperm; scaling; Allometry; angiosperm; Forest Inventory and Analysis National Program
• ISSN: 2045-7758; 2045-7758
• DOI: 10.1002/ece3.1328

The relationship between tree height and diameter is fundamental in determining community and ecosystem structure as well as estimates of biomass and carbon storage. Yet our understanding of how tree allometry relates to climate and whole organismal function is limited. We used the Forest Inventory and Analysis National Program database to determine height–diameter allometries of 2,976,937 individuals of 293 tree species across the United States. The shape of the allometric relationship was determined by comparing linear and nonlinear functional forms. Mixed‐effects models were used to test for allometric differences due to climate and floristic (between angiosperms and gymnosperms) and functional groups (leaf habit and shade tolerance). Tree allometry significantly differed across the United States largely because of climate. Temperature, and to some extent precipitation, in part explained tree allometric variation. The magnitude of allometric variation due to climate, however, had a phylogenetic signal. Specifically, angiosperm allometry was more sensitive to differences in temperature compared to gymnosperms. Most notably, angiosperm height was more negatively influenced by increasing temperature variability, whereas gymnosperm height was negatively influenced by decreasing precipitation and increasing altitude. There was little evidence to suggest that shade tolerance influenced tree allometry except for very shade‐intolerant trees which were taller for any given diameter. Tree allometry is plastic rather than fixed and scaling parameters vary around predicted central tendencies. This allometric variation provides insight into life‐history strategies, phylogenetic history, and environmental limitations at biogeographical scales. Tree height‐diameter allometry is plastic and scaling parameters vary around predicted central tendencies due to climatic variation. The magnitude of allometric variation due to climate depends largely on differences between angiosperms and gymnosperms.