Narrow Results

Micro-beam scanning PIXE (micro-PIXE) and scanning transmission ion microscopy (STIM) were applied to measurement of one-year-old seedling root from a Siebold's beech (Fagus crenata Blume) tree. The beech seedling root samples were collected at the centerpiece of the Shirakami-Sanchi World Heritage Area during October 2001. Target samples for micro-PIXE and STIM analyses were transverse sections from tip, midpoint and root of the beech seedling root. We focused shedding light on tree root metabolism, and are to get a real image about the elemental distribution in the tree root. STIM images were similar to those generated using stereomicroscope and/or transmission microscopy. Real images in the form of elemental maps were obtained for nine elements: Na, Mg, Al, Si, P, S, Cl, K and Ca. Of these, typical elemental maps were Si and Ca, which were both concentrated in the epidermis. Si was prominent in the tip, while Ca was prominent in the root.

Elemental distributions in a post oak leaf was measured using the Particle-Induced X-ray Emission (PIXE) technique and a proton microbeam at energy of 3 MeV with spatial resolution of 10 μm. The elements detected in this sample were Mg, Al, Si, P, S, Cl, K, Ca, Cr, Mn, Fe, Cu, Zn, Br, Rb, and Sr. Among them, spatial differences in the distribution of nine elements were observed between the vascular and mesophyll tissue. Si, Cl, K, and Ca were mostly accumulated in vascular tissue, while Mg, P, S, Cr, and Mn were for the most part accumulated in the mesophyll. The distribution of Ca appeared to follow cell wall contours. The distribution of some of these elements is compared to the function of the elements in living tissue and future possibilities for this type of investigation are discussed.