Soil has the ability to maintain its porous structure to allow passage of air and water, withstand erosive forces, and provide a medium for plant roots. Soils also provide anchoring support for human structures and protect archeological treasures.
The stability and support function of soil can be assessed by measuring the following indicators:
Soil Structure Indicators including bulk density, penetration resistance, porosity, or root growth pattern
Organic Matter Indicators including soil organic matter or total organic carbon
Also, inherent soil properties, like soil texture and particle size distribution, play a major role in physical stability.
Soil support is necessary to anchor plants and buildings. Both flexible (it can be dug) and stable (it can withstand wind and water erosion), soil also provides valuable long-term storage options including protecting archeological treasures and land-filling human garbage. The need for structural support can conflict with other soil uses. For example, soil compaction may be desirable under roads and houses, but can be devastating for the plants growing nearby.