The processes controlling the transport, uptake and fate of chemicals in soil are complex. The physico-chemical mechanisms, which dictate transport and exchange in structured porous media, need to be linked with the biophysical processes that determine the uptake and attenuation of chemicals by plant root systems. The challenge is to cobble these together so that we obtain a comprehensive understanding of the mechanisms controlling the leakiness of the rootzone, and the build-up, or attenuation of chemicals in the soil. We would then be able to provide better risk assessments of current land-management strategies and of remediation technologies for contaminated legacies.

New measurement devices tools are realising better observations, and these are being complemented by quantitative modelling for generalisation of our meagre measurements to allow better prediction of transport, uptake and fate processes in structured soils in the presence of roots.

Enhanced knowledge will arise first through interpretation of the improved observations using our new toys. From the breadth of this information, we can then use comprehensive modelling schemes to deepen our understanding of the exchange and transport processes, and of the uptake pathways and fate of chemicals in soil. Tools and models together will be the key.

We discuss new measurement technologies that are providing vision of greater acuity concerning the uptake of water and extraction of agrichemicals by distributed root systems. Fluxmeters are providing us with remote and real-time observations of the field fate of surface-applied agrichemicals. As well, in mesocosm lysimeters we have been able to assess the ‘filter efficiency' of the roots of poplar trees and willows to phytoremediate boron, and other metal contaminants. We discuss the application of phytoremediation to a contaminated wood-waste site.