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Rice, as a main crop, contributes to food security in Asia. However, its by-product, rice straw, poses challenges as it is often disposed of unsustainably. This research investigates the environmental performance of a 1000 m3 rice straw biogas pilot plant in Laguna, Philippines. A lifecycle assessment identified the climate change impact of the biogas system, straw burning and soil incorporation. In addition to GWP100, the global temperature potential's dynamic climate effects were assessed, including integrated radiative forcing and instantaneous temperature effects. The timeframe of the biogenic emission fluxes of rice production is particularly relevant as the sequestered CO 2 during plant growth is partly released as methane and CO 2 , depending on the straw management practices. Straw burning had the highest net emission impact. However, straw incorporation has the highest short-term radiative forcing and temperature increase. The biogas system provided significant short- and long-term GHG emission reduction of up to 68 % when biogas replaced burning or soil incorporation and the use of fossil fuels. Still, considerable uncertainties remain about fugitive methane emissions, handling and post-processing of the digestate. While single GHG emission figures on a GWP100 basis are useful for informing decision-making, this single-metric approach limits understanding of rice production's short- and long-term impacts. Additionally, our assessment emphasises the necessity for governance frameworks that promote sustainable practices in rice farming, as banning rice straw burning may result in less favourable outcomes from soil incorporation, whereas integrating biogas offers a solution benefiting rice-growing communities and global sustainability efforts. • Biogas from rice straw reduces emissions by up to 69 %. • Soil incorporation of straw has highest short-term (20 years) temperature increase. • Assessing more than one metric and timeframe supports more informed decision-making. • Governance frameworks enabling bioenergy integration support SDG 3, 7 and 13. [ABSTRACT FROM AUTHOR]

Abstract Forest-based bioenergy plays an important role in climate mitigation for limiting global mean temperature increase to below 2 °C. The greenhouse gas (GHG) impact of three forest-based bioenergy systems from the USA, Canada and Spain supplying wood pellets for electricity in the UK were evaluated by conducting lifecycle assessments and forest carbon modelling of the three forest systems. Cumulative emissions were analysed by calculating the forest carbon stock change and net GHG emissions balance of the forest-based bioenergy electricity. The analysis considered both the replacement of the existing electricity mix with bioenergy electricity and forest management with and without bioenergy use. The supply chain emissions and forest carbon balances indicated that GHG emission reductions are possible. However, the cumulative net GHG balance at forest landscape scale revealed that the reduction potential is limited, potentially with no GHG reductions in fast growing forests with shorter rotations, while slow growing forest systems with longer rotations result in greater GHG reductions. This means that the maximum climate benefit is delivered at a different point in time for different forest systems. To evaluate the climate change mitigation potential of forest-based bioenergy it is therefore necessary to consider the management, utilisation and relevant counterfactual of the whole forest and its products. In terms of climate change mitigation potential and minimising possible negative impacts that would require multi-level governance. Highlights • Net GHG balance shows GHG reduction potential of forest bioenergy is limited. • Results are dependent on methods, system boundaries and reference system. • Mitigation potential depends on forest management and whole forest product basket. • Multi-level governance framework require to track wider impacts of forest bioenergy. [ABSTRACT FROM AUTHOR]