Examination of embolisms in maple and birch saplings utilising microCT. (May 2023) - Robinson, James A.
Abstract: We demonstrate the application of synchrotron x-ray microtomography (microCT) to non-invasively examine the internal structure of a maple and birch sapling. We show that, through the use of standard image analysis techniques, embolised vessels can be extracted from reconstructed slices of the stem. By combining these thresholded images with connectivity analysis, we map out the embolisms within the sapling in three dimensions and evaluate the size distribution, showing that large embolisms over 0.005 mm 3 in volume compose the majority of the saplings' total embolised volume. Finally we evaluate the radial distribution of embolisms, showing that in maple fewer embolisms are present towards the cambium, while birch has a more uniform distribution. Graphical Abstract: ga1 Highlights: MicroCT images of a maple and birch sapling were taken using the Australian Synchrotron. Local thresholding is used to extract embolised vessels from 2D slices of 3D images. Connectivity analysis is used to map out embolisms as 3D structures. Large embolisms (>10 6 μm 3 ) compose most of the embolised volume in each sapling. In maple embolisms are distributed close to a growth ring while birch is more uniform.