Fig. 6.

Schematic presentation of the route of ¹⁰⁹Cd in the stem based on an interpretation of the heat maps in Fig. 5. The connection between the crown root (CR) and the main stem is indicated with a blue circle. ¹⁰⁹Cd was absorbed by the treated CR (1), then transported both downwards (2–1) and upwards (2–2) inside the stem. Some of the ¹⁰⁹Cd that was first transported downwards was further transported to nodal vascular anastomoses (NV) and then upwards along the central cavity (CC) (3). A small amount of ¹⁰⁹Cd was transported to the leaves (4, 7), whereas most of the ¹⁰⁹Cd remained inside the stem and was distributed both in peripheral cylinder of longitudinal vascular bundles (PV) and NV (5, 6) (this figure is available in colour at JXB online).