This symposium emphasizes on innovative use of indirect measurement methods to improve our understanding of the interacting physical and biological processes in the soil vadose zone. Methods include: Geophysical methods, radiography and computer aided tomography (X-ray, NMR, neutron) techniques, advanced air and space borne imaging. The symposium focus on advances in measurement interpretation through linking hydrological, biological, and instrument response models at different scales. We aim to highlight recent and expected future advances in non-invasive measurement techniques and improved interpretation of these measurements through coupled process and instrument modeling that promise to advance our understanding of biophysical soil processes.