Low availability of soil phosphorus is limiting organic grain production in Australia. Consequently, development of the organic food sector is being held back by a shortage of organic grain that is needed in almost every corner of the sector. Organic growers cannot use superphosphate to supply phosphorous for their crops, but they may use rock or soft phosphate, or compost with elevated phosphorus levels.

A possible alternative for organic farmers might be the use of wastewater precipitation products such as struvite or calcium phosphate. Struvite is a slow release phosphorus and magnesium fertiliser that is produced from the decant water of anaerobic digestion facilities processing wastewater from municipal, food processing or intensive animal industry sources.   

The project will seek to clarify whether and under which conditions particular sources of phosphorus derived from wastewater, such as struvite or calcium phosphate, can be allowed as inputs in certified organic farming systems in Australia.  

Results of the study, which will include a cost benefit assessment of using wastewater precipitation products and rock phosphate, will be presented in a discussion paper. The paper will be published on the Organic Trust Australia website and be also sent to Australian organic farming organisations.

Before you apply: contact the primary or associate supervisor for more details.

Location: Gatton and St Lucia

This project is available to Honours and Postgraduate Coursework students.

Project members

Primary Supervisor

Mr Johannes Biala

Research Centre Manager
School of Agriculture and Food Sciences

Associate Supervisors

Professor Victor Galea

Deputy Head of School
School of Agriculture and Food Sciences

Professor Susanne Schmidt

School of Agriculture and Food Sciences