Afforestation: Replacing livestock emissions with carbon sequestration.

Area of Science:

• Agricultural Science
• Environmental Science
• Forestry

Background:

• Agriculture contributes 33% of Ireland's greenhouse gas (GHG) emissions, jeopardizing EU climate targets.
• Livestock production is the primary driver of agricultural emissions in Ireland.
• Land use change and afforestation offer potential GHG mitigation through carbon sequestration.

Purpose of the Study:

• To estimate the net GHG emission reduction from replacing livestock systems with forests.
• To quantify carbon sequestration in biomass and wood products.
• To compare the social cost of carbon with livestock income and model national planting scenarios.

Main Methods:

• Estimating carbon sequestration per hectare for forests replacing dairy, beef, and sheep systems.
• Calculating avoided emissions from livestock systems.
• Modeling a national afforestation scenario of 100,000 ha.
• Comparing social cost of carbon with per-hectare income from livestock.

Main Results:

• Forestry replacing dairy production yields the highest GHG mitigation benefit.
• Dairy systems have high per-hectare emissions, while associated soils support high-yielding forests.
• Harvested wood products contribute to long-term GHG mitigation.
• A 100,000 ha afforestation scenario could abate 13.91 Mt CO2e in 10 years and over 125 Mt CO2e per rotation.

Conclusions:

• Forest land use change is crucial for reducing agricultural GHG emissions in Ireland.
• Replacing livestock, especially dairy, with forests offers substantial climate benefits.
• Strategic afforestation can significantly contribute to meeting national and EU climate commitments.