Impacts of hydraulic redistribution on grass–tree competition vs facilitation in a semi-arid savannah.

Dr. Greg Barron-Gafford, Principle Investigator of eco-physiology at Biosphere 2, and his team in the School of Geography and Development at the University of Arizona, have been researching the interactions between SFM1 Sap Flow Meters, Eddy Flux towers and Photosynthesis data to investigate Hydraulic Redistribution (HR). While this is a highly documented physiological phenomenon, the impact of Hydraulic Lift (HL) and Hydraulic Redistribution by trees on the functioning of other members of the ecosystem has not been extensively researched.

In an effort to evaluate both the positive (through HL) and the potentially negative effects (through Hydraulic Descent; HD) Dr. Barron-Gafford and his team asked two key questions: How do patterns of HR influence overstorey and understorey plant eco-physiological functions? and How do these patterns vary across timescales of an individual precipitation pulse to an entire growing season?

Please link to the New Phytologist publication doi: 10.1111/nph.14693 to discover the findings of this exciting research that has already been downloaded from the publishers website over 156 times and is listed in the top 25% of all research products published by Wiley.  You may be very surprised by the results. They may even cause you to challenge the current dogma about trees and their role in ecosystem functioning. You may also rethink your eco-physiological experimental design and monitoring protocols, and the need to include more non-destructive, and continuous high temporal resolution measurements such as sap flow.  

Regards
Alec Downey B.Sc. (For)
Head of Plant Science Applications & Research
ICT International Pty Ltd
Adjunct Senior Lecturer,
School of Plant Biology, University of Western Australia