The potential of biomineral fertilisers to increase soil carbon sequestration

Summary

This project aims to assess the ability of Troforte Cropping Plus, biomineral fertiliser, to increase soil carbon sequestration, while at least maintaining productivity and profitability in relation to best practice conventional fertiliser use. It will be explored through an Integrated R&D PDS model and is relevant to all livestock producers currently implementing a fertiliser regime. 

It is proposed that bio-mineral fertilisers will reduce carbon emission through two pathways: 

• By increasing the formation of permanent humus compounds and through an increase in the soil organic matter stability. Consequently, the contribution of the organic matter fractions that are more resistant to decomposition are crucial for increasing soil carbon sequestration. This is achieved by: 

• microbes in biomineral fertiliser colonise roots and drain more carbon to the rhizosphere soil to increase soil carbon pool 
• biomineral fertiliser increases root biomass which are the sources of carbon locked up in the soil over time. 

• Bio-mineral fertilisers will improve soil biological fertility, plant nutrition and reduce carbon emissions by increasing nutrient density of pastures and subsequently increasing weight gain efficiency of livestock. Possible anti-methanogenic impacts will also be assessed.    

The carbon footprint of a biomineral and conventional fertiliser regime will be calculated to determine the ability of biomineral fertilisers to be a tool for reducing net GHG emissions from an improved pasture system.   

Objectives

1. Assess the potential of biomineral fertilisers to increase soil carbon, above that of conventional fertilisers.  
2. Assess the carbon emissions of a biomineral and conventional fertiliser regime in a pasture fed beef system typical of south west WA. 
3. Assess the ability of biomineral fertilisers to maintain or exceed productivity and profitability of conventional fertiliser regimes, including a cost benefit analysis. 
4. 70% of all core and observer producers increase their knowledge around biomineral fertilisers, soil carbon, strategies to increase it and carbon accounting by 60%.   
5. 75% of livestock producers to consider the importance of implementing production systems changes to reduce operational greenhouse gas emissions within their operation. 
6. 75% of core producers (minimum 10) to have trialled or started the process to implement a new fertiliser regime. 
7. 40% of observer producers (minimum 60) to have trialled or started the process to implement a new fertiliser regime 

Progress

This project aims to assess the ability of Troforte Cropping Plus, biomineral fertiliser, to increase soil carbon sequestration while at least maintaining productivity and profitability in relation to best-practice conventional fertiliser use.  The project will involve a central on-farm trial site and three producer demonstration sites in southwest WA.   

Now entering the 3rd year of the project, pasture quantity and quality measurements, soil tests and animal weight gains have continued to be measured. To date, significant differences have not been identified between treatments groups on any measure. Awareness raising and capacity building activities have been run annually with focus on topics such as soil carbon, carbon farming, soil nutrition and fertiliser use. Three core producers have also completed carbon accounts for the businesses.