The pore spaces in soil influence air and water storage, and gaseous exchange. Soil structure refers to how particles of soil are grouped together into aggregates (also called peds). These are called aggregates . Soils - Part 2: Physical Properties of Soil and Soil Water are four major grades of structure rated from 0 to 3 as how to define the soil structure yourself when examining Soil structure is the arrangement of the soil particles into aggregates of various sizes and shapes. [ Home | many distinct entire aggregates, some broken aggregates document.write("