CPlantBox parameter XMLs are divided into
modelparameter/structural 
modelparameter/functional

modelparameter/structural is divided into 
plant/ for whole plant parameter sets, and
rootsystem/ for rootsystem only parameters.
Literature sources for the rootsystem parameter sets can be found in 
https://figshare.com/collections/CRootBox_parameter_files/3745478

modelparameter/functional contain additional parameter sets 
(e.g. hydraulic parameters for soil and plants, climate data, ...)


