Simulated Hydrologic Consequences of Soil Heterogeneity, Macropores, and Tree Farming

摘要

Computer simulation applications in basic (soil heterogeneity, macropore) and applied (tree farming) hydrologic research have been undertaken with deterministic models based on soil (physical) and plant (physiological) processes. Under high evapotranspiration conditions, soil variability tended to be hydrologically unimportant. Conversely, during storm events, runoff was preferentially generated from finer soils, but with increase in storm intensity, coarser soils generated runoff. Simulation of soil-water flow through large channels (macropores) and the interaction of this flow with fine pores showed that macropores were hydrologically active under conditions of ponded infiltration or perched water tables within the soil profile. Under these conditions, macropores were shown to increase the interaction of water with a profile (relative to a profile without them) by increasing vertical drainage and by delaying the onset of lateral runoff. (ERA citation 07:003637)