PLANTS IN WATER-CONTROLLED ECOSYSTEMS: ACTIVE ROLE IN HYDROLOGIC PROCESSES AND RESPONSE TO WATER STRESS - II. PROBABILISTIC SOIL MOISTURE DYNAMICS

Abstract

A stochastic model for soil moisture dynamics at a point is studied in detail. Rainfall is described as a marked Poisson process, producing a state-dependent infiltration into the soil. Losses due to leakage and evapotranspiration also depend on the existing level of soil moisture through a simplifying but realistic representation of plant physiological characteristics and soil properties. The analytic solution of the steady-state probability distributions is investigated to assess the role of climate, soil, and vegetation in soil moisture dynamics and water balance.