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Future projections indicate an expansion for both food and energy demands, which can increase pressure on land use, while there is an urgent global need for climate change mitigation. Bioenergy is foreseen as key option to meet future energy demands and reduce greenhouse gas (GHG) emissions, however its sustainability depends on locations and regional characteristics. Simultaneously, agricultural production models that co-produce food, feed, and energy offer sustainability synergies and co-benefits, but site-specific sustainability assessments of their large-scale implementation are missing. This study presents a bottom-up approach to assess spatially explicit sustainability aspects of bioenergy-livestock integrated systems (BLI) in Brazil and shed light on their contribution to future energy demands, to climate change mitigation targets, and their impacts on selected ecosystem services, including bioenergy production, climate change mitigation, reduction of food competition, biodiversity conservation, and avoided deforestation. The proposed integration considers livestock intensification and use of biofuels by-products as animal feed supplement, taking advantage of synergies between these two value chains. The expansion of the BLI system in the Center-South region of Brazil produce up to 89 billion liters of ethanol, enough to meet future domestic ethanol demands from multiple shared socioeconomic pathways and generating surpluses for export. This production takes place on 16 million hectares of pastureland within the Sugarcane Agroecological Zoning, excluding the Amazon and Pantanal biomes, and biodiversity hotspots. BLI expansion mitigate up to 250 million tonnes of CO 2 eq and generate 15 billion dollars of profits. The best locations to maximize the selected ecosystem services are west of São Paulo, east of Mato Grosso do Sul, and the south-central region of the states of Goiás. This study may encourage the formulation of enhanced public policies for the integration of bioenergy and livestock value chains and guide a sustainable large-scale deployment of BLI systems. • Bioenergy and livestock integration (BLI): co-production of food, feed and energy. • BLI systems: 89 billion liters of ethanol and 250 million tonnes of CO 2 eq mitigated. • Enough ethanol to meet future Brazilian demands and surplus to be exported. • Biomass expansion only on pastureland inside Sugarcane Agroecological Zoning. • Without land displacement and deforestation of native vegetation. [ABSTRACT FROM AUTHOR]

Urbanisation and the associated growing climate change burdens pose risks to urban and global climate resilience. Urban greenhouse gas emissions fluctuate over time in response to energy demand, which is influenced by government programmes, economic activity, and demographics. In this research, we investigate the influence of policy on urban energy demand and its consequences on mitigating climate change impacts. Using a case study of Lisbon, Portugal from 2008 to 2016, we illustrate a combined use of an urban energy metabolism assessment coupled with a logarithmic mean Divisia index to isolate the changes in energy-related carbon emissions associated with policy changes. We then link these energy flows to life cycle emissions factors to build a multi-level assessment between local and non-local global warming potential. We find that in 2016 Lisbon's energy flows generated more than 2 Mt of CO 2 -equivalent emissions over their life cycles, 48% of which were direct emissions within the city. This corresponds to a decrease of around 37% in greenhouse gas emissions from 2008. Additionally, we estimate the potential of Lisbon's urban forests to sequester these emissions to understand the potential for climate change mitigation. Results show that Lisbon's urban forest can meet less than 1% of the emissions throughout the assessment period. We discuss the changes, concluding that urban forests are insufficient in size to meet the sequestration demands of the urban energy metabolism, and therefore the focus must be more attuned to reducing fossil fuel use in the urban trade and transport activities. • Carbon emissions from Lisbon's urban energy metabolism are dominated by diesel use in the trade and transportation sectors. • Carbon emissions from Lisbon's urban energy metabolism have decreased following energy policy interventions. • Less than 1% of Lisbon's energy-related carbon emissions are sequestered by urban forests. • Urban forests are insufficient in size to mitigate the demand for carbon sequestration. • Energy policy must focus on reducing urban demand for diesel and petrol by transport activities. [ABSTRACT FROM AUTHOR]