The Role of Soil Architecture in Pedological Processes.

Soil architecture (structure) is the physical constitution of solid particles and voids into secondary polyhedral assemblages at multiple scales (macro, messo, and micro). Peds are aggregates of those assemblages separated by natural surfaces of weakness (coatings of sesquioxides, clays, organic-clay complexes, carbonates, stress features, etc.). Pedologists have long recognized the importance of soil architecture (landforms, pedons, horizons, peds, microfabrics, and submicroscopic units) in differentiating soils of different quality and function. Processes in which soil architecture is critical to soil function include water transport and flux, solute movement, aeration capacity, sorption/desorption kinetics, diffusion rates, mass flow, gas transport, biotic activity, and biomass productivity.  It has been said that a crushed or pulverized sample of the soil is related to the soil formed by nature like a pile of debris to a demolished building.  Neither the structure nor behavior of a soil can be inferred from a crushed sample any more than the architecture of  ba building from a pile of bricks. Future efforts should be made to measure field and laboratory soil properties on an in-situ basis.