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    Author(s): Annikki Makela; Harry T. Valentine
    Date: 2006
    Source: Journal of Theoretical Biology. 243: 283-285.
    Publication Series: Scientific Journal (JRNL)
    Station: Northern Research Station
    PDF: Download Publication  (119.74 KB)


    West, Brown, and Enquist (1997, 1999) propose an integrated model of the structure and allometry of plant vascular systems, which has come to be known as the 'WBE model' (Enquist, 2002). The WBE model weaves together area-preserving branching (Leonardo da Vinci), elastic similarity (Greenhill, 1881), the constant ratio of foliage mass to sapwood area (Shinozaki et al., 1964), and elements of fractal geometry (Mandelbrot, 1983) into a cohesive quarter-power scaling theory for trees and other plants. This model has become widely cited, but it also has been subjected to both theoretical and empirical criticism. For example, Kozlowski and Konarzewski (2004) argue that the assumption of fixed size of the terminal internode leads to inconsistencies, while the emprical results by Meinzer et al. (2005) are in conflict with the model predictions on conducting cross-sectional area and transpiration rates in trees. From our own analysis, we have noticed an unreported issue that seems to be worthy of comment.

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    Makela, Annikki; Valentine, Harry T. 2006. The quarter-power scaling model does not imply size-invariant hydraulic resistance in plants. Journal of Theoretical Biology. 243: 283-285.

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