Simultaneous modeling of transient three-dimensional root growth and soil water flow

Abstract

A model is presented for the simultaneous, dynamic simulation of soil water movement and plant root growth. Root apices are translocated in individual growth events as a function of current local soil conditions. A three-dimensional finite-element grid over the considered soil domain serves to define the spatial distribution of soil physical properties and as framework for the transient water flow model. Examples illustrate how field-observed morphology of root systems can be approximated by including even a coarsely discretized description of the soil environment. Intended as a tool for testing of hypotheses on soil-plant interaction, simulations can be performed for different levels of model complexity, depending on how much information is available. At the simplest level, root growth is simulated without soil water uptake, whereas the most comprehensive level includes growth of the shoot and dynamic assimilate allocation to root and shoot.