No tillage

What

No, or reduced, tillage refers to the practice of sowing or planting a new crop after harvest, without first tilling the soil. In this way the soil gets less disturbed, although you often rake the soil to make it possible to set the seeds or plantings.   

Where

In cultural landscapes cultivating arable fields for crop production. 

Why

No tillage has the potential to counteract societal challenges mainly related to biodiversity enhancement, food security, climate change mitigation and adaptation, disaster risk and preparedness and water management. This is done through the following pathways: 

  • Increased soil microbial activity 

  • Improved soil ecosystem integrity 

  • Improved habitats for invertebrates  

  • Increased soil organic carbon in long term 

  • Reduced greenhouse gas emissions 

  • Decreased soil erosion 

  • Decreased nutrient leakage  

How

Instead of tilling the soil after harvest, a lighter and shallower raking is usually performed to reduce weeds and to make room for concurrent seeding or planting. Sometimes special machinery is used to prepare the land before sowing or planting, but it is also possible to use existing rakes. 

Potential outcomes

No tillage usually has the benefits of reducing the disturbance of soil ecosystems, including fungi mycels networks and worm burrowing. No tillage can also contribute to improved habitats for invertebrates, such as beetles and spiders important for biological pest control.  

No tillage can also reduce greenhouse gas emissions by limiting the detrimental damages to soil organism. This can also stabilize soil organic carbon level, contributing to healthier soils and hence crop yields.

Other benefits can be to increase agriculture resilience to weather variability by, for example, increasing water absorption and contention. The risk of erosion is usually decreased, perhaps with the most effect in loess soils.  

ATTENTION

As a consequence of not ploughing away weeds, these need to be removed by other means. Some farmers use herbicides, which add to the total load of pesticide entering the environment and is also a cost for the farmer. Other techniques that can also be used are dense sowing, mulching, crop rotation (especially between broad leaf plants and grass), and intercropping. 

How much do we know

Reduced or no tillage agriculture is now a well-established method in many parts of the world where tillage was previously standard practice.  

Costs

There can be a reduced cost in terms of cut fuel consumption when heavy ploughing is avoided. There can be an initial cost in machinery for alternative practices. Some management systems will reduce weeds by spraying the fields before raking. In this case the pesticide cost can increase. 

References

Blanco-Canqui, H., & Ruis, S. J. (2018). No-tillage and soil physical environment. Geoderma, 326, 164-200. 

Li, Z., Zhang, Q., Li, Z., Qiao, Y., Du, K., Yue, Z., ... & Li, F. (2023). Responses of soil greenhouse gas emissions to no-tillage: A global meta-analysis. Sustainable Production and Consumption, 36, 479-492. 

Mathew, R. P., Feng, Y., Githinji, L., Ankumah, R., & Balkcom, K. S. (2012). Impact of no‐tillage and conventional tillage systems on soil microbial communities. Applied and Environmental Soil Science, 2012(1), 548620.