Examination of embolisms in maple and birch saplings utilising microCT

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 mm3 in volume compose the ma-jority 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.

Automated summary

We used synchrotron x-ray microtomography (microCT) to examine the internal structure of maple and birch saplings. Embolised vessels were extracted from reconstructed images through image analysis, and embolisms within the saplings were mapped out in three dimensions. We evaluated the size distribution of the embolisms, finding that larger embolisms compose the majority of the total embolised volume. Furthermore, we compared the radial distribution of embolisms in maple and birch saplings.