MAPPING THE WATER PATHWAYS IN STEM XYLEM BY SAP FLOW MEASUREMENTS DURING BRANCH SEVERING EXPERIMENTS
The Heat Field Deformation (HFD) sap flow method proved to be a useful tool for analyzing whole-tree hydraulic architecture in trees. It measures sap flow rates, at different sapwood depths, with high time and space resolution. The response of multi-point sensors inserted in tree stems to manipulation experiments (such as branch severing) unravels the link between conducting xylem of stem and different foliage cohorts. The changes in the sap flow profile upon branch cuttings are easy to follow and interpret, especially when conducted under clear sky conditions. Based on experiments carried out in trees with different hydraulic architectures, we demonstrate the potential of the HFD method in the fast direct evaluation of the extent of the stem sapwood connected to each part of the crown and hence in the mapping of the water pathways between stem and crown. Such xylem maps may substantially contribute to the modeling of water transport in trees.
Nadezhdina, N., David, T.S., David, J.S., Nadezhdin, V. and Pinto, C.A. (2013). MAPPING THE WATER PATHWAYS IN STEM XYLEM BY SAP FLOW MEASUREMENTS DURING BRANCH SEVERING EXPERIMENTS . Acta Hortic. 991, 223-230
heat field deformation, hydraulic architecture, radial profile, water pathways