Raymundo Marcos-Martinez

Material extraction underpins economic development and human well-being but is also a major driver of greenhouse gas emissions, biodiversity loss, pollution, and resource depletion. Yet no globally agreed target for material use reconciles environmental limits with the resource requirements for decent living standards. We integrate macroeconomic, land-use, stock-flow, and multiregional input-output modelling to compare a baseline with four global transition scenarios to 2060. Despite different policy mixes, the scenarios converge on a sustainable range of approximately 107–123 billion tonnes of annual material extraction, equivalent to 9–13 tonnes per person, while substantially reducing environmental impacts. Comparing material footprints with material stocks reveals persistent trade-offs between environmental ambition and equitable development, leaving only limited scope to expand essential infrastructure in low-income countries. These findings provide a scientifically grounded reference range for global material use and support differentiated national pathways that combine environmental ambition with fairness and political feasibility.

Cities concentrate environmental burdens and mitigation opportunities, yet current assessment approaches remain fragmented between building-scale precision and city-scale coverage. This study develops and demonstrates a multi-scale, spatially explicit framework that links city, suburb, section, and building scales, embedding environmental assessment outputs within an interactive web-based viewer. The approach is applied to Canberra (Australia), integrating LiDAR-derived low-detail building geometries, BIM-based construction archetypes, and Australian-specific life cycle inventory data to quantify and visualize embodied impacts for material production and transport stages (A1–A4). Environmental indicators are aggregated hierarchically using Australia’s Statistical Areas (SA2 and SA1) and explored through ”Urban Visualization Levels” (UVLs). The analysis focuses on building mass per capita and total global warming potential (GWP), visualized as bar height and color, respectively. Results reveal strong spatial heterogeneity and show that values do not vary linearly across the urban fabric. A boundary-condition selection identifies four contrasting suburban configurations (Dunlop, Kambah, Majura, and Civic), illustrating how demographic scale and land-use functions can drive divergent per-capita and absolute impact profiles within the scope of embodied impacts assessed. Finer-scale inspection at UVL-1 and UVL-2 exposes substantial intra-suburb variability and the presence of localized high-impact buildings, particularly in central areas where a few large buildings dominate the scene. The study demonstrates the value of interactive, multi-scale visualization to support transparent interpretation of urban embodied-impact assessments. The framework is transferable to other cities with comparable input data and can be extended to additional impact categories and BIM-enabled analyses as these models become increasingly available.

Food systems face multi-dimensional pressures and require integrated assessments of environmental, social, health and economic dimensions to inform their transformation. Although economic equilibrium models and integrated assessment models have been instrumental in this context, future decision-making requires more diverse and inclusive participatory processes. Here we evaluate the ability of current models to represent food systems and identify challenges and opportunities regarding key aspects of their transformative change, including socio-political dynamics and human–nature feedbacks, links between global and local scales, robustness under uncertainty, as well as evolving stakeholder demands. Our analysis underscores the need to rethink how models are designed and used for a more effective integration into decision-making processes.

As cities grow, demand for urban materials is set to rise. Meeting sustainability targets will require transformative changes to how cities are constructed. Yet, accurate information on embodied building materials and their environmental impacts at the city scale is still lacking. We use Light Detection and Ranging data, building archetype information, and statistical models to estimate the embodied materials in buildings in Canberra, Australia, and their energy, carbon, and water footprint. In 2015, 57 million tonnes (Mt) of materials were embodied in 140,805 buildings. By weight, concrete was the most used material (44%), followed by sand and stone (32%), and ceramics (11%). Current population growth and building construction trends indicate a need for 2.4 times the building materials stock of 2015 by 2060. Producing such materials would require 1.6 thousand TJ of energy and 793 thousand megaliters of water and emit 48 Mt of CO ₂ e—an environmental footprint 1.6 times the one in 2015. If the additional population were to live only in new single houses, material demand would be 4% higher than under current trends and the environmental footprint 5% higher. Housing new residents in low‐rise apartments would reduce from current trends the material demand by 5% and the environmental footprint by 12%. Using only apartments of four or more stories would reduce material demand by 28% and the environmental footprint by 14%. This research can inform circular economy efforts to improve building materials management by helping estimate the implications of alternative configurations of the urban built environment.

The protection and expansion of forest carbon sinks are critical to achieving climate-change mitigation targets. Yet, the increasing frequency and severity of forest disturbances challenge the sustainable provision of forest services. We investigated patterns of forest disturbances’ impacts on carbon sinks by combining spatial datasets of forest carbon sequestration from biomass growth and emissions from fire and bark beetle damage in the western United States (U.S.) and valued the social costs of forest carbon losses. We also examined potential future trends of forest carbon sinks under two climate-change projections using a global vegetation model. We found that forest carbon losses from bark-beetle damage were larger than emissions from fires between 2003 and 2012. The cumulative social costs of forest carbon losses ranged from USD 7 billion to USD 72 billion, depending on the severity of global warming and the discount rate. Forest carbon stocks could increase around 5% under Representative Concentration Pathway (RCP) 4.5 or 7% under RCP 8.5 by 2091 relative to 2011 levels, mostly in forests with high net primary productivity. These results indicate that spatially explicit management of forest disturbances may increase forest carbon sinks, thereby improving opportunities to achieve critical climate-change mitigation goals.

China experienced a shift from net forest losses to gains (forest transition) between 1976 and 1981. Such transition has increased timber volume in natural forests and expanded the provision of forests ecosystem services. However, the timing, magnitude, and impact of the forest transition varied at provincial scales due to heterogeneous socio‐economic and institutional conditions. The aim of this study is to quantify the impact of spatial drivers of forest transition in China through integrated comparative and spatial regression methods. This approach allows the documentation of feedbacks and interactions of theoretical pathways to forest transition at different geographical scales, which is of relevance for large‐scale land restoration efforts. Our analysis also accounts for changes in forest volumes, a parameter that is usually not studied in the forest transition literature. Here, we used key indicators of demographic, economic, agricultural, and urbanization processes coupled with forest area data to investigate factors influencing forest transitions at multiple geographic scales between 1973 and 2013. Stepwise and geographically weighted regression models were adapted to quantify the key drivers' integrated and distributed magnitude effects on forest transition patterns, respectively. We assessed changes across forest types (i.e., primary and secondary forests, plantation forests) and investigated pathways to forest transition at provincial scales. The results indicate that increasing demand for timber and other forest ecosystem services, rising gross domestic product and population, forest policy, and increasing employment in the industry and service sectors generated multiple pathways to forest transition. The impact of those drivers varied within provinces, and some transition pathways were more relevant than others at sub‐national scales. Despite the Country scale shift to net forest gains, the loss of natural forests continued in some provinces (e.g., Guangdong, Guangxi) until recent years. The loss of ecosystem services from mature forests offset some of the benefits of China's forest transition. Coordinated forest management strategies across political jurisdictions could speed up the path to net forest gains, reduce trade‐offs of forest transitions processes, and achieve sustainable afforestation processes. Such an effort could have significant contributions to the preservation and increase of key forest ecosystem services for the Country and the world.

Around two‐thirds of the global population will live in cities by 2050 requiring large urban infrastructure development. Decision‐makers and planners usually rely on standard economic accounting methods for urban planning and investments on infrastructure assets. However, standard methods fail to account for the ecosystem services benefits that living infrastructure (e.g. urban forests, open spaces) provides to city dwellers. This could generate socially inefficient configurations of urban spaces and compromise the achievement of long‐term urban sustainability targets. In this analysis, we applied a stochastic whole‐of‐life benefit–cost analysis following the System of Environmental‐Economic Accounting (SEEA) framework to compare alternative long‐term management strategies for living infrastructure in Canberra, Australia. Spatially explicit data, i‐Tree Eco and benefit transfer methods were used to estimate the stocks and flows ecosystem services benefits of urban forests and irrigated open spaces from 2018 to 2070. Our analysis suggests that a ’30 per cent canopy cover expansion’ scenario has the highest benefit–cost ratio, while the business as usual scenario, where a net loss of 400 trees is expected per year, offers the lowest benefit–cost ratio. Scenarios of expanding versus not expanding irrigated open spaces in the future both result in a benefit–cost ratio of approximately two.