Soils, Fertilisers and Nutrients

Healthy productive soils are a key driver of dairy farm profitability. Poorly managed soils and over-application of fertiliser can lead to poor environmental outcomes. The Australian dairy industry is setting new world standards in tracking nutrient movement on dairy farms and their spread into the wider catchment.

The Dairy Australia soils and nutrients research and development programme has three main goals:

1. Soils- Maintain or enhance the structure and biological functionality of the soil resource in the dairy production system
2. Nutrients- Ensure efficient and best application of nutrients to support optimum pasture growth and maintain animal health in the dairy production system
3. Farms in Catchments- Ensure closed nutrient systems for farms so over-application and nutrient runoff into the catchment do not occur.

Major projects:

Accounting for Nutrients

Nutrient accounting is a technique used to quantify nutrient inputs and outputs either at a whole-farm or paddock scale, in order to determine nutrient deficits or surpluses, in an attempt to improve nutrient use efficiency and reduce nutrient losses from agriculture.

As dairy farming in Australia continues to intensify, increasing stocking rates and greater inputs of purchased feed and fertiliser have resulted in an imbalance between nutrient inputs, primarily as feed and fertiliser, and nutrient outputs, in milk and livestock, at the farm scale. Additionally, the uneven distribution of recycled nutrients between paddocks, and the accumulation of nutrients in non-productive areas, creates the potential for nutrient accumulation in some areas and deficiencies in others. This imbalance results in significant inefficiencies in nutrient use within dairy farms and an increased risk of nutrient loss to the environment.

A standardised nutrient accounting framework will improve the dairy industry’s understanding and management of nutrient requirements and nutrient flows, increase the efficient and profitable use of nutrients and reduce nutrient losses from dairy farms.

A key part of the A4N project is the detailed collection of information and samples from 44 contrasting dairy farms from across Australia. This includes determining the amounts and concentrations of purchased feed and fertiliser, the export of milk and animals, and the within-farm management of grazing rotations, fertilisers, dairy effluent, and harvesting and feeding of forages.

For more information contact Cameron Gourley, Project Leader and Senior Research Scientist, Department of Primary Industries Victoria.

Current projects

• Accounting for nutrients on Australian dairy farms (Project reference, DAV12307)
• Montagu catchment soil phosphorus and pasture calibration (Project reference, UT12676)
• Defining the soil phosphorus maintenance requirements of dairy pasture soils (Project reference, UT12108)
• Identification of soil tests for prediction of run off (Project reference, DAN12752)
• Topsoil mixing by cultivation on a hydrosol to reduce off-site nutrient losses at the paddock scale in the Montagu catchment (Project reference, UT13174)

• Novel soil amendment technology for minimising nutrient losses from dairy pastures for the protection of water bodies: Major study (Project reference, UA12286)
• Flaxley farmlets- Nutrient loads in run-off water at high stocking densities (Project reference, DAS10815)
• Novel soil amendment technology for minimising nutrient losses from dairy pastures for the protection of water bodies (Project reference, UA11129)
• Making better fertiliser decisions for grazed pastures in Australia (Project reference, DAV11211)
• Defining the soil phosphorus maintenance requirements of dairy pasture soils (Project reference, UT12108)