Estimating the Water Use of a Sclerophyllous Species under an East‑Mediterranean Climate

Gabriel Schiller, Eugene D. Ungar, and Yehezkel Cohen  
Forest Ecology and Management, vol. 170, nos. 1-3 (October 2002), pp. 117-126 [full text]
 
Abstract (p. 117)
 
 
Water use by vegetation is the most important parameter which is directly related to plant anatomical and 
eco-physiological characters, and to soil-bedrock water availability. This basic parameter is important in decision making, planning and management of the open areas under semiarid climatic conditions like those of Israel. Attempts were made to quantify the water use by Phillyrea latifolia L. by means of the heat pulse method. This method provides continuous monitoring of the convective heat pulse velocity (HPV) in the trunk xylem, thus facilitating the quantification of the transpiration flux per tree. The daily and annual water use by this species was estimated by extrapolations from the single-tree transpiration rates, based on the relationship between the leaf area of the measured trees and the entire area. 
 
The lithological properties of the bedrock formations in each of the research sites caused significant differences between sites in the average daily transpiration rate and, hence, in the total water use by the Phillyrea latifolia scrub formation. The daily transpiration, averaged over a year, ranged between 4.00 and 8.15 l. day per tree, and the estimated annual water use ranged between 179.4 and 365.5 mm, i.e., between 30 and 61% of the annual rainfall in the winter preceding the measurements in 1993.
 
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Gabriel Schiller: Department of Agronomy and Natural Resources, Agricultural  Research Organization, The Volcani Center; Corresponding author: Tel: +972-3-9683875, Fax: +972-3-9669642, E-Mail: [email protected]
Eugene D. Ungar: Department of Agronomy and Natural Resources, Agricultural Research Organization, The Volcani Center Yehezkel Cohen: Department of Environmental Physics and Irrigation, Agricultural Research Organization, The Volcani Center