HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Furon, A. C. Articles by Wagner-Riddle, C. Search for Related Content PubMed Articles by Furon, A. C. Articles by Wagner-Riddle, C. Agricola Articles by Furon, A. C. Articles by Wagner-Riddle, C. Related Collections Landscape-Atmosphere Interactions Evapotranspiration Models

Modeling

Analysis of Scaling-Up Resistances from Leaf to Canopy Using Numerical Simulations

Department of Land Resource Science, Univ. of Guelph, Guelph, ON, Canada N1G 2W1

^* Corresponding author (jwarland{at}uoguelph.ca)

A multi-layer model, combining Lagrangian dispersion at the canopy level with Ohm's Law analogy at the leaf level, was used in numerical simulations to assess the leaf-to-canopy scale translation of surface resistances. The model produced unique profiles of fluxes and scalar concentrations that satisfied both the dispersion and leaf models. Environmental factors and canopy architecture were varied, and stomatal conductance was simulated using either a simple relationship with net radiation or the Ball and Berry model to account for feedback mechanisms. Results showed that, when the assumptions of the Penman–Monteith equation were met, scaled-up leaf conductance closely matched the bulk canopy conductance. However, as the scenarios modeled departed from the ideal conditions of Penman–Monteith, the agreement decreased. In particular, correct estimation of the aerodynamic resistance, through correct parameterization of the roughness length for sensible heat, was identified as a key issue.

Abbreviations: B&B, Ball and Berry model • D&M, Denmead and Millar model • ICM, ideal canopy model • P-M, Penman–Monteith equation