The critical soil water content and its relation to soil water dynamics

A umidade crítica e sua relação com a dinâmica da água no solo

Using an edaphic model that describes the extraction of soil water by plant roots, the occurrence of depletion zones dose to plant roots is demonstrated. These depletion zones affect the root water potential that is needed to maintain a certain transpiration rate. The results show how the critical soil water content depends on soil's hydraulic properties, transpiration rate and root density.

Critical soil water content; soil water extraction; soil water dynamics

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