Root System Scale Models Significantly Overestimate Root Water Uptake at Drying Soil Conditions.

ABSTRACT: Soil hydraulic conductivity (k _soil ) drops significantly in dry soils, resulting in steep soil water potential gradients (ψ _s ) near plant roots during water uptake. Coarse soil grid resolutions in root system scale (RSS) models of root water uptake (RWU) generally do not spatially resolve this gradient in drying soils which can lead to a large overestimation of RWU. To quantify this, we consider a benchmark scenario of RWU from drying soil for which a numerical reference solution is available. We analyze this problem using a finite volume scheme and investigate the impact of grid size on the RSS model results. At dry conditions, the cumulative RWU was overestimated by up to 300% for the coarsest soil grid of 4.0 cm and by 30% for the fine

SUBMITTER: Khare D 

PROVIDER: S-EPMC8882956 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature