Plant water relations of Tamarix ramosissima in response to the imposition and alleviation of soil moisture stress

Academic Press
Publication Type:
Journal Article
Journal Of Arid Environments, 1997, 36 (3), pp. 527 - 540
Issue Date:
Full metadata record
Files in This Item:
Filename Description Size
Thumbnail2008008750OK.pdf255.69 kB
Adobe PDF
The effect of an extended drydown on the water relations ofTamarix ramosissima(saltcedar), a desert phreatophyte, was investigated along the floodplain of the Virgin River (southern Nevada) during a hot dry summer period. Seedlings ofTamarixwere grown in lysimeters (120 cm depth, 51 cm radius) positioned along a gradient from the desert's edge to the interior of the stand and monitored for growth and evapo-transpiration over a 2-year period prior to this study. Water tables were maintained at approximately 60 cm during the evapo-transpiration study by applying weekly irrigation directly to the water table via piezometers. At the end of the 2-year period, three lysimeters were selected for a drydown experiment (desert's edge, river's edge, open stand). On 7 July 1995 all irrigation was terminated for a 29-day period. After the drydown period was over, irrigation was applied for an 18-day period to re-establish water table depths. Sapflow (transpiration) was monitored during the entire 47-day period (drydown, wetup) with stem flow gauges, soil moisture with time domain reflectometry, and plant water relations with a steady state porometer and pressure chamber. Results indicated that sapflow decreased significantly as water tables and stored soil water declined. Daily sapflow totals on a leaf area basis were higher for the plant growing along the river's edge, with midday hourly values significantly higher when a water table was present.
Please use this identifier to cite or link to this item: