Evidence for Farming Initiative Greenhouse Gas Reduction and Carbon Storage on Dairy Farms

This report provides high-level insight into the evidence landscape around transitioning to net zero in the dairy sector to feed into the Evidence for Farming Initiative (EFI). EFI aims to improve agricultural performance through providing farmers, growers and their advisers with easy access to the best available evidence on effective and cost-effective practices to carry out both emission reduction and opportunities for carbon capture and sequestration. The dairy sector is perceived as a key contributor to greenhouse gas (GHG) emissions and the aim is to provide evidence-based advice as to the effectiveness of farmer interventions.

Promar carried out primary source research and evidence gathering to support initial decision-making on the overall setting of direction for EFI in the dairy sector. An extensive list of relevant GHG reduction interventions in the dairy sector was created which was then reduced to focus on eight core areas of interventions that it was felt would make significant difference and be achievable by dairy farmers. The eight core areas, using the EFI evidence review framework, were investigated in detail to create this report. Promar were also tasked to identify key areas where supporting evidence was unavailable or lacking that could potential form AHDB research projects for the dairy sector in the future.

The initial ‘long list’ demonstrated the complexity of the range of GHG effecting interventions in the dairy sector and how they interacted and impacted on each other. Promar grouped the interventions into eight core areas:

1. Organic manures
2. Energy use and renewables
3. Fertility and herd management
4. Herd health and welfare
5. Genetics and genomics
6. Feed strategy and management
7. Carbon capture
8. Soil carbon

Under each core area a specific intervention was investigated in more detail. These interventions were:

1. Low emission spreading
2. Reducing energy consumption from fossil fuels
3. Heifer rearing
4. Mortality rate
5. Increase the genetic merit of the herd
6. Homegrown feed quality
7. Agro-forestry
8. Increasing soil organic matter

Each of the eight interventions was evaluated on the cost, effectiveness, strength of evidence and outcomes using the EFI framework. From the eight chosen there was variation on cost and effectiveness but all apart from feed strategy & management had a 60% or higher level of effectiveness. Key challenges will be to use the current knowledge exchange tools available to encourage and demonstrate to farmers the environmental and economic benefits of implementing these interventions. As a result of this report some specific areas requiring further research evidence have been identified and similarly the necessity to understand the issues regarding transfer value of carbon footprints when implementing these activities.