Ecological Archives C006-029-A2
Frances C. O'Donnell, Kelly K. Caylor, Abinash Bhattachan, Kebonye Dintwe, and Gregory S. Okin. 2015. A quantitative description of the interspecies diversity of belowground structure in savanna woody plants. Ecosphere 6:154. http://dx.doi.org/10.1890/es14-00310.1
Appendix B. Extrapolation procedure for missing roots.
Root system taper and branching rates were too irregular to determine a reliable average, so we extrapolated using other recorded root paths. For each lost root, we identified all sections of completely mapped roots with a diameter less than 30% larger or smaller than the last measured diameter of the lost root that were also within the same depth layer as the last measured section of the lost root. We then narrowed the group of “candidate” root sections to those in voxels with an r coordinate no more than 50 cm more or less than the r coordinate of the voxel containing the last section of the lost root. We ran simulations in which we randomly selected one candidate root for each lost root. The path, mass, and branching of the selected candidate were assumed for the remainder of the lost root. We ran sets of 100 simulations for each excavated tree and found that different realizations did not change the values of interest in our analysis by more than 10%, with the exception of the first tree excavated, which had a large number of lost roots.