A tomographic inversion approach for the detection of decay and cavities in tree trunks using ground penetrating radar

A variety of tree species, such as ash and oak trees, are nowadays under serious threat in the United Kingdom and European territories as a result of the action of aggressive fungal diseases. To this effect, Ground Penetrating Radar (GPR) is an effective geophysical tool capable of collecting information on the internal structure of trees. Nevertheless, traditional processing methods can provide only limited indications for health monitoring purposes. In this study, a demonstration of the GPR potential and the use of a tomographic inversion approach in detecting decay and cavities is provided. In that context, a set of finite-difference time-domain (FDTD) simulations of different complexity (i.e. internal trunk configurations and dimensions of the targets) were used to assess the performance of the proposed strategy. The results prove the viability of the proposed approach in identifying the position of cavities and decay in tree trunks.