Impact

Conservation tillage

No-till

Aggregate stability

Organic matter concentrated near surface, encourages microbial growth, increasing aggregate stability.

Crop residue at surface prevents surface crusting, increasing aggregate stability.

Compaction

Improves surface structure due to concentration of residues, decreasing compactibility; Can cause additional compaction in the untilled layer.

Dependent on soil type.

Soil mineralization

Shallower depth with no soil inversion so releases less N for crop uptake than conventional tillage, which leads to less mineralization.

Emergence and root growth

Decreases soil temperature and increases residue, thus impeding crop emergence; Root growth depends on biological macropore ability to compensate for absence of mechanical macropores.

Soil water storage and infiltration

Increases C content in soil, which increases water storage capacity and water retention; Infiltration depends on soil type and biological porosity.

Weeds

Compared to conventional, more weeds in general.

Disease and pest control

Conventional tillage more effective for control of soil-bourne pathogens, but increased biological activity of conservation and no-till can form disease-suppressive soils.