Root surfaces represent one of the most important phase boundaries in nature, since most mineral nutrients essential for life enter the biosphere and the food chains of the animal world through the roots of higher plants. Similarly, root water and nutrient uptake is one of the most important processes considered in numerical models simulating water content and fluxes in the subsurface, thus controlling water flow (recharge) and nutrient transport (leaching) to the groundwater, and exerting a major influence on predictions of global climate models. In addition to soil transport mechanisms, nutrient uptake is controlled by the spatial distribution of roots, as influenced by its architecture, morphology, and presence of active sites of nutrient uptake, including root hairs.

In this special section, we seek original contributions that advance theory and modeling of root-soil interactions, as determined by a wide number of environmental variables, including atmospheric forcing, moisture, nutrient and other stresses, and that include root water and nutrient uptake processes. We especially seek examples across a wide range of spatial scales, including the global scale, and advances in numerical approaches that couple flow and transport in the presence of roots, and that include experimental data.