Figure 6. Composite elemental distribution images of irrigated and drought-exposed leaves (A, B) and fine roots (C, D) of Cupressus sempervirens saplings.

Elemental distribution images (heat maps; a single color per element) were created at 20 µm resolution and scan area of 500 µm with a copper target to detect Fe, Mn, Ca, K, and Cl, and molybdenum or gold target to detect Cu and Zn. The mapping was performed using an X-ray fluorescence microscope applying an ultra-high brightness X-ray source with multiple X-ray targets.