week 2 - reducing tillage

what are the impacts of tillage on soil physical properties?

exposes soil surface, breaks up soil aggregates, increases/causes soil compaction

why is having an exposed soil surface an issue?

- Increases erosion risk

- Promotes surface crusting

- Widens soil temperature ranges

why is breaking up soil aggregates an issue?

- Increases wind and water erosion

- Exposes soil organic matter to oxidation

why is soil compaction an issue?

- Reduces water infiltration

- Reduces nutrient uptake

- Poorer root growth

what are the impacts of tillage on soil biology?

· Removes plant cover

- Interrupts flow of exudation into soil

· Inverts the soil

- Destroys biopore channels

- Biologically active surface layer is buried under subsurface layer

· Increases microbial respiration

- Nutrients released

- Soil organic matter consumed

how does reduced tillage improve soil health?

improves soil structure, reduced global warming potential over time, increases soil carbon over time

improvement in soil pore connectivity under reduced/zero tillage

· Soil porosity decreases in the first few years under ZT

· Soil structure regenerates after 5 years