Plants in water-controlled ecosystems: active role in hydrologic processesand response to water stress - II. Probabilistic soil moisture dynamics

A stochastic model for soil moisture dynamics at a point is studied in deta il. Rainfall is described as a marked Poisson process, producing a state-de pendent infiltration into the soil. Losses due to leakage and evapotranspir ation also depend on the existing level of soil moisture through a simplify ing but realistic representation of plant physiological characteristics and soil properties. The analytic solution of the steady-state probability dis tributions is investigated to assess the role of climate, soil, and vegetat ion in soil moisture dynamics and water balance. (C) 2001 Elsevier Science Ltd. All rights reserved.