Promoting Infiltration


Soil texture greatly affects water infiltration. Coarse textured soils (sandy loams, etc.) have large pores that promote high infiltration rates. Fine-textured soils (silt loams and clay loams) generally have smaller pores and lower infiltration rates. Soil texture cannot be changed, so we must work within this constraint. However, we can improve infiltration rates by soil management techniques that promote soil aggregation.

Soil aggregation impacts the pore distribution of a soil. The degree of aggregation can be changed by soil management techniques. Frequent tillage destroys soil aggregation. Conversely, no-till (along with crop residue additions) can help restore aggregation. Finer texture soils must have good structure that promotes large pore spaces so water can enter the soil. Any practice, such as tillage, that destroys soil aggregates or decreases soil aggregate size and decreases surface pore space ultimately will reduce water infiltration into the soil and promote evaporation and runoff.