Comparison of two methods for estimating the evaporation of a Pinus pinaster (Ait.) stand: sap flow and energy balance with sensible heat flux measurements by an eddy covariance method

• Published in: Agricultural and forest meteorology Vol. 54; no. 1; pp. 49 - 66
• Main Authors: Diawara, A, Loustau, D, Berbigier, P
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.01.1991; Oxford Elsevier; New York, NY Elsevier Masson
• Subjects: Agricultural and forest climatology and meteorology. Irrigation. Drainage; Agricultural and forest meteorology; Agricultural sciences; Agronomy. Soil science and plant productions; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Life Sciences; Silviculture, forestry; Water balance and requirements. Evapotranspiration; Pinus pinaster; Sensible heat; Temperature; Sap; Europe; Wind velocity; Thermal energy storage; Heat flow; Evaporation; Forest understorey; Energy balance; Gironde; Transpiration; Aquitaine; Gymnospermae; Softwood forest tree; Evapotranspiration; Forest canopy; Coniferales; Spermatophyta; Measurement method; France; Microclimatology; PIN MARITIME
• ISSN: 0168-1923; 1873-2240
• DOI: 10.1016/0168-1923(91)90040-W

A method combining sensible heat flux measurement based on temperature and vertical wind speed fluctuations, and energy balance, was used to estimate evaporation above the canopy and the understorey of a Pinus pinaster (Ait.) stand in Les Landes forest. The problems of the horizontal homogeneity of net radiation and sensible heat flux under the canopy, and of estimating heat storage, are reviewed. The differences between above- and below-canopy evaporation are compared with sap flow on five experimental days. Except for one overcast day with little tree transpiration, the method fits sap flow within ± 15%.