Back to results

CONSERVATION TILLAGE

Conservation tillage is a method of establishing crops in the leftover waste of a previous crop. The approach means that limited or no tillage is undertaken and aims for a minimum of 30% area coverage by the remaining waste of the Image removed. previous year’s crop. The waste of the previous year’s crop creates a mulch that protects topsoil and allows natural decomposition process thereby increasing the organic matter of the soil. This is turn slows water movement through the soil, reduces erosion and improves nutrients. The approach can boost yields due to the improved soil structure and less compacted soil.

  • Maintains soil fertility.
  • Maintains soil quality and provides protection against wind erosion.
  • Reduces water run-off and improves water infiltration to the soil which can improve recharge of groundwater aquifers.
  • Minimising the amount of tillage promotes sequestration of carbon in the soil.
  • The change in soil structure may present new challenges like different pests and weeds.
Indicative cost

Conservation tillage is very low cost that does not require significant capital works but requires human resources. Whilst providing cost estimates is difficult given the broad range of influencing factors across the Pacific, the below table outlines the key components that should be taken into account when estimating an conservation tillage project budget for a specific location.

Components

Unit
(A)

Number of units (B)

Unit Cost
(C)

Budget
(B x C)

Establishment Cost

        
  • Planning and design including community outreach

e.g hours

      
  • Materials (e.g. plants, equipment)

e.g number

      
  • Labour

e.g. hours

      
  • Reporting to donor (if required)

e.g. hours

      

Ongoing Cost

        
  • Maintenance Cost (materials and labour)

e.g. number and hours

      
  • Reporting and Monitoring

e.g. hours

      

Conventional tillage is the conventional method of farming in which soil is prepared for planting by completely inverting it with a pulled plough. Comparison of conventional and conservation tillage includes: 
Image removed.

  • Conventional tillage disturbs the soil and leaves a bare surface while conservation tillage creates minimal soil disturbance.   
  • Crop residue is burnt or removed in conventional system while residue is retained on the soil surface in conservation tillage which leaves mulch to protect the topsoil from erosion.
  • Conservation tillage conserves soil, water and energy resources.

 

 

On-ground impacts that the EbA option addresses
Erosion
Nutrient losses
Increasing prevalence of invasive species

Case study

Conservation Agriculture Practice for taro production

Palau

Due to low agricultural production, 85% of food products consumed in Palau are imported. The Palau Government is trying to increase domestic production of foods such as Taro. To address the challenges of poor soil fertility, the Palau Government has trialed adoption of conservation agriculture. The trial comprised the adoption of three principles:

  • Minimum soil disturbance
  • Permanent residue cover
  • Crop rotations

For the trial, conservation agriculture was undertaken using a portable gas-powered auger and a trencher, with the aim of improving soil fertility. Field studies were undertaken to test the impact on taro production. The studies showed that the highest yield was achieved using minimum tillage (auger and trencher with betel nut leaf mulch) compared to conventional tillage approaches. Adopting a conservation tillage approach also led to lower levels of erosion.

Reference: On-site trial for conservation agriculture with local resources, https://www.jircas.go.jp/sites/default/files/publication/agriculture_in_palau/agriculture_in_palau-_94-114.pdf