Potential role of tree introduction in agricultural land to reduce greenhouse gas emissions

The European Union (EU) has proposed legislative revisions to achieve climate neutrality in EU by 2050. The Land Use, Land-Use Change and Forestry (LULUCF) Regulation, adopted in 2018, is being revised to ensure that accounted greenhouse gas (GHG) emissions from LULUCF are balanced by equivalent accounted removals of carbon dioxide (CO2) from the atmosphere. This study focuses on the impact of targeted tree introduction in agricultural land in Latvia, specifically afforestation of drained organic soil and implementation of agroforestry systems (riparian buffer strips), on national GHG reduction targets for the LULUCF sector. The potential contributions of selected measures were evaluated using evaluation methods including GHG emissions factors based on the Intergovernmental Panel on Climate Change (IPCC) guidelines and recent scientific studies. The study differentiated between different land use categories by GHG emissions from soil and CO2 removals in living biomass, dead wood, litter, mineral soil, and organic soil. Basic scenarios were compared with additional scenarios that included afforestation of drained organic soils and implementation of agroforestry systems. The study analysed the possibilities of achieving LULUCF sector goals for 2030, 2035, and 2050 with the selected scenarios. According to the basic scenarios, the LULUCF sector has been a continuous source of GHG emissions since 2019, partly compensated by forest management by 2040, but after 2040 forest management becomes a source of GHG emissions as well. The study shows that afforestation of organic soils currently used for agricultural production can reduce GHG emissions and ensure the achievement of national LULUCF targets for 2021–2025, with a significant decrease in GHG emissions by 3.9 million t CO2 eq. during the 2021–2025 period if compared to the basic scenario. However, the study finds that national target of net GHG removals is not achieved for 2026–2030 according to both basic and afforestation scenarios if no additional measures, e.g., establishment of the shelter belts, are implemented.