Patterns of water transport in tree rings of four tree species

We took tree rings as the basic unit to investigate water transport patterns of four tree species(Populus alba×P.berolinensis, Quercus mongolica, Pinus koraiensis, Larix olgensis) through dye test of sap flow and titration analysis. The results showed that the capability of water transport remarkably differed among tree rings. The newly-formed rings(latest three rings) were more capable of transporting water, accounting for over 2/3 of the total water transport area. However, inter-ring water transport was not detected. The four tree species demonstrated different patterns of water transport in longitudinal direction(from the root to the top), i.e., linear, helical, sartorially radial or their combinations. These types were referred to as “water transport patterns in tree rings”.