Water vapor transfer from a vegetated surface: A numberical study of bulk transfer coefficients and canopy resistances

✍ Scribed by W. J. Massman; A. Dijken

• Publisher: Springer
• Year: 1989
• Tongue: English
• Weight: 820 KB
• Volume: 49
• Category: Article
• ISSN: 0006-8314
• DOI: 10.1007/bf00120974

✦ Synopsis

The semi-analytical model outlined in previous studies (Massman, 1987a. b) to describe momentum and heat exchange between the atmosphere and vegetated surfaces is extended to include water vapor exchange. The methods employed are based on one-dimensional turbulent diffusivities and use numerical solutions to the steady-state diffusion equation. The model formulates stomata1 response as a function of vapor pressure deficit and the within-canopy profile of mean photosynthetically-active radiation (PAR). It is then used to assess the influence that foliage structure, density, and sheltering can have upon the bulk transfer coefficient. kB,.-I, and the canopy resistance. A general analytical formulation of the canopy resistance based on the mean within-canopy profile of PAR is proposed and found to agree with the model's solutions for canopy resistance to within a few percent.

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