Anthropogenic nitrogen (N) losses from croplands have risen alongside global food production and are a major driver of transgressed planetary boundaries. Price-based policy instruments are widely proposed to curb agricultural nitrogen pollution, yet their effectiveness and distributional consequences under market feedbacks remain insufficiently understood. Here we assess the global impacts of nitrogen pricing on cropland N losses, food security and economic outcomes. We extend the global land-use model GLOBIOM by endogenizing crop- and country-specific nitrogen balances and explicitly representing multiple N-loss pathways. Field-level mitigation technologies are incorporated, with adoption governed by marginal abatement costs, yield effects and economic affordability, allowing nitrogen taxation and subsidies to interact with production decisions, land allocation and international trade. Without additional intervention, global cropland N losses increase by 28% by 2050 relative to 2020. Nitrogen taxation reverses this trend, reducing N losses by 22% (12–29%) compared with business as usual, but at the cost of higher food insecurity. Field-level mitigation technologies provide a critical buffer, delivering additional abatement and offsetting nearly one-third of the food-security losses induced by taxation. In contrast, mitigation subsidies implemented alone yield limited net mitigation, as technology-driven reductions are partly offset by subsidy-induced cropland expansion. Combining taxation, subsidies and technologies yields the most balanced outcome, reducing global N losses by 23 Tg N by 2050 while moderating food-security impacts. Responses to nitrogen pricing vary strongly across regions. Under the combined policy scenario, South Asia, East Asia and Europe together account for about 58% of global mitigation, but through distinct pathways. Economically resilient regions mainly achieve mitigation through higher adoption of field-level technologies and declines in N-loss intensity, with mitigation shares exceeding their emission shares. Less affluent regions rely more on trade adjustments, shifting part of the mitigation burden to exporting regions through virtual N flows. These contrasts translate into marked distributional effects: technologies and subsidies offset more than half of taxation-induced farmer revenue losses in high-income regions, whereas buffering effects remain limited in some low-income regions, with mitigation costs increasingly borne by consumers and governments. Overall, price-based nitrogen mitigation can halt the long-term rise in global N pollution, but its effectiveness and equity critically depend on technology deployment and policy design and must be aligned with broader food-system transformations.

Parties to the Convention on Biological Diversity (CBD) agreed upon goals and targets for biodiversity in the Kunming-Montreal Global Biodiversity Framework (GBF). The success of the GBF depends on the collective actions of the Parties, i.e. member states, to the CBD. Essential challenges in this context include ensuring that efforts across Parties are sufficient to collectively meet global ambitions, are integrated across biodiversity and other sustainability dimensions, and are just and value-explicit. In this perspective, we lay out how scenario- and model-based research can support this process. We describe how designing scenario narratives and quantifying different aspects of these narratives, specifically, target downscaling and narrative-specific modelling, combined with evaluating planned and implemented actions towards the GBF, can create locally relevant knowledge to help address these challenges and support a successful GBF. We highlight the importance of co-producing such knowledge and identify potential entry points for disseminating the outcomes at the science-policy interface, informing relevant national and global biodiversity governance.

Internationally, it has been agreed to halt and reverse biodiversity loss, a commitment partly underpinned by model-based scenario analyses showing that bending the trend is possible. These scenarios provide insights into alternative future biodiversity trends and their drivers. Our meta-analysis differentiates scenarios that project biodiversity loss and that halt or reverse the trend based on their quantitative outcomes and explores their key characteristics such as scenario assumptions, drivers of loss, biodiversity indicators and models used. We found that bending-the-curve studies are scarce, and mostly do no account for climate change, which risks suggesting that the trend can be bent too easily. Our findings indicate that bending is only achievable with integrated efforts across different sectors, such as nature conservation, sustainable food production, diet change, and reduced food waste. To better support policymaking, scenarios should be based on model intercomparisons and use standardize indicators to allow comparisons across studies, account for additional drivers of loss to represent the real threats to biodiversity, and include more ambitious cross-sectoral actions to effectively bend the curve.

As part of Workpackage 7 of the CLEVER project, this deliverable describes scenario and model applications to explore the future impact of trade in three non-food biomass supply chains (soy, forest, crop aquafeed) on biodiversity and ecosystem services, and the impact of alternative supply chain governance. The applications have a a global coverage and, for soy and forest supply chains, a focus on EU and Brazil. The scenarios were co-designed through desk research, input from empirical analysis of supply chains conducted in other work packages of the CLEVER project and feedback supply chain-specific stakeholder workshops. They include an exploratory dimension - covering key future drivers of each supply chain - as well as alternative interventions along supply chain segments (e.g., conservation and restoration, production, demand and trade regulations), including specific EU and Brazil policies in the case of soy and forest supply chains. The scenarios were then assessed with the GLOBIOM global partial equilbrium model of the agriculture, forestry, bioenergy and blue food sectors, with projections of key indicators related to each supply chains and covering market (e.g., production, trade, consumption) as well as socio-economic (e.g., value added, food avalabilty) and environmental (e.g., land and water use, GHG emissions, biodiversigty loss) dimensions, at a decadal time step from 2000 to 2050 (or 2100 in the case of the forestry sector). This deliverable presents and discusses the model projections. This is version 2.0. Difference to previous version: Figures 19 (for PLA CON&BIO scenario) and Figure 24 (for both scenatios) was corrected for erroneous data (with no significant impact on results), and the PROJECT OUTPUT ACHIEVED section was updated with links to updated data records (with minor corrections and addition of code to reproduce figures from model outputs)

Water underpins agricultural adaptation to climate change, yet irrigation accounts for nearly 70% of global freshwater withdrawals. Whether water systems can sustain further irrigation expansion under climate change remains uncertain. We quantify when irrigation crosses soft and hard adaptation limits under alternative climate futures by 2050. Using an integrated modeling framework linking crop cultivations, hydrology, land use and trade, we evaluate future contributions and sustainability of irrigation across water, land and economic indicators. Under low warming, irrigation stabilizes global production while withdrawals decline by 17%, and blue water use efficiency improves by 25%, functioning as an efficiency-enhancing adaptation. As warming intensifies, irrigation shifts from efficiency to dependency: sustaining production increasingly requires rising withdrawals, with efficiency declining by 27–32% in major producing regions. Climate change also weakens global trade-related blue water savings, reinforcing unequal virtual water exchanges between the Global South and North. Water availability, not agronomy alone, ultimately defines the limits of irrigation-based adaptation.

Ambitious global goals and targets to address ongoing declines in biodiversity and nature’s contribution to people (NCP) have been adopted in the Kunming-Montreal Global Biodiversity Framework (GBF). For a successful GBF, Parties to the Convention on Biological Diversity (CBD) face the challenge of ensuring that collective actions are sufficiently ambitious, integrated across actions and sustainability dimensions, and that they consider plural values of nature and diverse perceptions of justice. Without successfully addressing this challenge, national actions for the GBF risk 1) falling short of adding up to global-level ambitions; 2) generating unnecessary trade-offs between sustainability outcome goals and between action targets through lack of policy coherence, and 3) stalling over conflicting views about what is fair and sustainable. Here, we propose a range of complementary research activities, centred on further developing model and scenario applications, through which sustainability research can help address these challenges to better support progress towards the GBF. The key research activities we discuss are a) designing plural integrated, value- and justice-explicit scenario narratives of nature- and people-positive futures, b) downscaling global biodiversity targets to country level following different distributive justice and nature value perspectives, c) evaluating planned and implemented country actions towards the GBF, and d) modelling scenarios of both nature- and people-positive narratives, and planned and implemented country actions. We present example applications of these components, including a set of nature- and people-positive scenario narratives that explore different value perspectives on nature and plural perceptions of justice, as well as downscaling selected GBF targets. We highlight how analytical outputs from the suggested research activities may enrich crucial national and global processes (including the global analysis and review of collective progress towards the GBF and revisions and the implementation of National Biodiversity Strategies and Action Plans and national targets) to ensure a successful GBF, through sufficiently ambitious, integrated, value- and justice-explicit collective actions.

There is limited understanding of what transformative change towards climate and biodiversity goals might entail in the context of food and biomass systems, and the specific role of justice as a leverage point for transformative change. Competing perspectives on justice lead to different preferences for how food and biomass systems are reshaped, and a deeper understanding of those competing perspectives may foster collaborative action. To address this gap, we developed and quantified three contrasting pathways designed to meet biodiversity, climate and human wellbeing goals through transformative change, but picturing contrasted value perspectives about environmental justice and human-nature relationships.The three developed pathways, Global Green Innovation (GGI), Global Stewardship Towards Co-Existence (GS), and Needs-Based and Nature-Connected Local Stewardship (LS), involve interventions across multiple domains, coherently linked through assumptions about their dominant values, based on the Nature Futures Framework (NFF) and the Applied Justice Taxonomy and Assessment (AJUST) framework. Key intervention domains include food consumption patterns, food waste and loss strategies, cropland and forest management, conservation and restoration, trade, biomass demand, and climate change mitigation. To capture different alternative value perspectives on human-nature relationships and distributive justice, the pathways are differentiated in terms of distribution of efforts across regions and interventions domains.The qualitative narratives were quantified and analyzed using the Global Biosphere Management Model (GLOBIOM). The GLOBIOM model was expanded to include additional interventions (e.g., more diversified land use practices for cropland and forest management, alternative dietary and food consumption inequality trajectories) and socio-economic and environmental indicators (e.g., human health impact from food consumption, value of production, labor in crop production, multiple driver-response pathways for biodiversity based on the GLOBIO and LC-IMPACT biodiversity models).We will introduce the new pathways, and analyze the quantitative projections of socio-economic and environmental impacts from 2020 to 2050, with a focus on how the pathways differ in terms of their implied distribution of impacts across supply chain actors (e.g., consumers, livestock vs crop producers) and world regions, and in terms of trade-offs between socio-economic and environmental impacts.

AbstractAgricultural trade was an important driver of habitat and biodiversity loss in the recent decades (Chaudhary & Kastner 2016). Yet, it might also have increased land use efficiency and the net biodiversity impacts are heterogeneous across regions, commodities and spatial scales (Kastner et al. 2021, Roux et al. 2021). Trade greening is identified as a key leverage point to reverse global biodiversity declines (Chan et al. 2020), and future trade could be deeply affected by the food system sustainability transition needed to reach ambitious goals for climate, biodiversity and people (Leclère et al. 2020). To explore uncertainties in the co-evolution of agricultural trade and biodiversity in the coming decades, we used the GLOBIOM partial equilibrium model of the agricultural, forestry, bioenergy and aquaculture sectors (Havlík et al. 2014) to quantify a set of scenarios.A first scenario dimension contrasted a future baseline prolongating historical trends (Middle of the Road Shared Socioeconomic Pathway SSP2, Popp et al. 2016) with additional efforts towards bending the curve of global biodiversity loss (Leclère et al. 2020) including increased conservation and restoration alone, or cumulated with a faster convergence of agricultural yields, reduced waste and increased share of plant-based products in diets. These scenarios are first combined with the standard SSP2 trade setup, and then combined with three alternative future trade variants as a second scenario dimension (Enhanced trade liberalization, Frictions and reconfigurations, Trade greening).Preliminary results showed positive future socio-economic impacts and negative future environmental impacts in a scenario prolongating historical trends. Assuming an exacerbated liberalization worsened environmental impacts for mixed effects on socio-economic indicators, while trade frictions & reconfiguration would have mild environmental gains and negative socio-economic impacts as compared to the baseline. Trade Greening could have moderate positive impacts on all metrics as compared to the baseline. Relatively high levels of future increases in trade flows were found despite lower environmental impacts when assuming additional conservation and supply-side efforts. However, assuming additional demand-side efforts was more disruptive, with much larger environmental gains and food security risk reduction as compared to the baseline, but also much smaller future increases in agricultural value added and trade flows.References:Chan, KMA et al. (2020) Levers and leverage points for pathways to sustainability. DOI: 10.1002/pan3.10124Chaudhary, A, Kastner, T. (2016) Land use biodiversity impacts embodied in international food trade. DOI: 10.1016/j.gloenvcha.2016.03.013Kastner, T et al. (2021) Global agricultural trade and land system sustainability: Implications for ecosystem carbon storage, biodiversity, and human nutrition. DOI: 10.1016/j.oneear.2021.09.006Roux, N et al. (2021) Does agricultural trade reduce pressure on land ecosystems? Decomposing drivers of the embodied human appropriation of net primary production. DOI: 10.1016/j.ecolecon.2020.106915Leclère, D et al. (2020) Bending the curve of terrestrial biodiversity needs an integrated strategy. DOI: 10.1038/s41586-020-2705-yHavlík, P et al. (2014) Climate change mitigation through livestock system transitions. DOI: 10.1073/pnas.1308044111Popp, A et al. (2016) Land-use futures in the shared socio-economic pathways. DOI: 10.1016/j.gloenvcha.2016.10.002

The Fisheries and Marine Ecosystems Model Intercomparison Project (FishMIP) has dedicated a decade to unraveling the future impacts of climate change on marine animal biomass. FishMIP is now preparing a new simulation protocol to assess the combined effects of both climate and socio-economic changes on marine fisheries and ecosystems. This protocol will be based on the Ocean System Pathways (OSPs), a new set of socio-economic scenarios derived from the Shared Socioeconomic Pathways (SSPs) widely used by the Intergovernmental Panel on Climate Change (IPCC). The OSPs extend the SSPs to the economic, governance, management and socio-cultural contexts of large pelagic, small pelagic, benthic-demersal and emerging fisheries, as well as mariculture. Comprising qualitative storylines, quantitative model driver pathways and a "plug-in-model" framework, the OSPs will enable a heterogeneous suite of ecosystem models to simulate fisheries dynamics in a standardised way. This paper introduces this OSP framework and the simulation protocol that FishMIP will implement to explore future ocean social-ecological systems holistically, with a focus on critical issues such as climate justice, global food security, equitable fisheries, aquaculture development, fisheries management, and biodiversity conservation. Ultimately, the OSP framework is tailored to contribute to the synthesis work of the IPCC. It also aims to inform ongoing policy processes within the United Nations Food and Agriculture Organization (FAO). Finally, it seeks to support the synthesis work of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), with a particular focus on studying pathways relevant for the United Nations Convention on Biological Diversity.

Research data and code access for the paper - A modeling framework to assess nutrient loadings to lake and their drivers: a case study of Lake Victoria Basin

To mitigate biodiversity loss from agriculture, intensification is often promoted as an alternative to farmland expansion. However, its local impacts remain debated. We assess globally the responses of three biodiversity metrics-species richness, total abundance and relative community abundance-weighted average range size (RCAR), a proxy for biotic homogenization-to land conversion and yield increases. Our models predict a median species loss of 11% in primary vegetation in modified landscapes, and of 25% and 40% in cropland within natural and modified landscapes, respectively. Land conversion also reduces abundance and increases biotic homogenization, with impacts varying by geographic region and history of human modification. However, increasing yields changes biodiversity as well, including in adjacent primary vegetation, with effects dependent on crop, region, biodiversity metric and natural habitat cover. Ultimately, neither expansion nor intensification consistently benefits biodiversity. Intensification has better species richness outcomes in 29%, 83%, 64% and 57% of maize, soybean, wheat and rice landscapes, respectively, whereas expansion performs better in the remaining areas. In terms of abundance and RCAR, both expansion and intensification can outperform the other depending on landscape. Therefore, minimizing local biodiversity loss requires a context-dependent balance between expansion and intensification, while avoiding expansion in unmodified landscapes.

Reversing the declines in biodiversity trends is a widely adopted goal, reflected in both the Kunming-Montreal Global Biodiversity Framework, and the EU 2030 Biodiversity Strategy. In this presentation, we will show two examples of how models and scenarios can be mobilized to provide support to achieving these goals in the context of the broader sustainable agenda. In a first example, multiple economic and biodiversity models are used to assess long-term, global scale, pathways aiming to explore whether—and how—humanity can reverse the declines in terrestrial biodiversity caused by habitat conversion reverse global biodiversity losses (Leclere et al, 2020). The results show that i) immediate efforts of unprecedented ambition and coordination could enable reversing the global terrestrial biodiversity trends caused by habitat conversion, and ii) that an integrated approach, combining increased protection and restoration efforts with sustainable production and consumption measures, is essential to not only enable a bending of global biodiversity trends before 2050, but also limit trade-offs and harness synergies with other sustainable goals. In a second example, we will demonstrate how models and scenarios are also mobilized to support policy design at the EU scale, with an application focusing on assessing the land use, LULUCF emissions and biodiversity implications of EU climate (e.g., Fitfor55 package and LULUCF regulation) and biodiversity (e.g., Nature Restoration Law) and their interactions.

Eating a lot of meat and dairy puts pressure on nature. It leads to deforestation, water pollution, and climate change. By 2050, there will be over 9 billion people on Earth. Without any change in the way we eat, environmental damage will only get worse. What if we could eat foods that taste like meat and milk, but without hurting the planet as much? Novel plant-based foods, like plant-based burgers or oat milk, are made to taste and feel like animal products while using less land, water, and producing fewer greenhouse gases. Traditional plant-based foods, like tofu, lentils, and chickpeas are also healthy, tasty, and better for the planet. If everyone gradually replaced half of their meat and dairy with plant-based options we could save forests, reduce emissions, and make food more affordable. Even small changes in diet can make a big difference for the planet—and our future.

The European Union is committed to achieving ambitious area-based conservation and restoration targets in the upcoming decade. However, there is concern that these targets risk conflicting with socioeconomic needs, particularly for food, timber and bioenergy production. Here we develop an integrated spatial planning approach to identify where restoration, conservation and production allocation could maximize benefits to species conservation and climate mitigation, while acknowledging future land demands of the bio-economy. We show that, while changing production demands risk driving further biodiversity loss by 2030, when these demands are met alongside strategic restoration measures, as outlined by the EU Nature Restoration Regulation, future landscapes could improve the conservation status of populations for more than 20% of species of conservation concern while also increasing terrestrial carbon stocks. Our analysis demonstrates how critical the Nature Restoration Regulation is to achieving biodiversity targets and how integrated planning can align biodiversity policy objectives with future socioeconomic demands.

To reduce the biodiversity impact of agriculture, increasing yields on existing farmland has been proposed as an alternative to farmland expansion. However, the relative effects of yield increases versus agricultural expansion have mostly been examined regionally, and measured in terms of species persistence—a metric relevant to extinction risk but limited in describing ecological communities and their support for ecosystem services. Without a thorough analysis, the lower biodiversity impacts of agricultural intensification remain largely speculative. This study provides a global assessment of biodiversity responses to land conversion and yield increases, including closing yield gaps. We also compare the biodiversity impacts of expanding farmland versus intensifying yields in agricultural landscapes to achieve a 1% increase in total production. Utilizing a large biodiversity database, natural vegetation data, and agricultural yield estimates at the landscape scale, we assess three biodiversity metrics: species richness, total abundance, and relative community abundance-weighted average range-size (RCAR), which provides a proxy for biotic homogenisation. Our models highlight that land conversion is associated with significant biodiversity loss at both local and landscape scales, emphasizing the importance of avoiding farmland expansion into new landscapes. However, yield also lead to significant biodiversity loss; closing yield gaps is associated with a median species loss of nearly 11%, and median abundance loss of almost 13%, with some agricultural landscapes losing almost 90% of species and more than 90% in abundance. Additionally, 30% of global agricultural landscapes, predominantly in the tropics, are likely to experience increased biotic homogenization. Neither expansion nor intensification is consistently better for biodiversity, with biome type, crop, biodiversity metric, and percentage of natural vegetation influencing which approach is less harmful. Our results suggest that minimising the biodiversity cost of agriculture requires a context-dependent balance between intensification and expansion in agricultural landscapes.

Based on an extensive model intercomparison, we assessed trends in biodiversity and ecosystem services from historical reconstructions and future scenarios of land-use and climate change. During the 20th century, biodiversity declined globally by 2 to 11%, as estimated by a range of indicators. Provisioning ecosystem services increased several fold, and regulating services decreased moderately. Going forward, policies toward sustainability have the potential to slow biodiversity loss resulting from land-use change and the demand for provisioning services while reducing or reversing declines in regulating services. However, negative impacts on biodiversity due to climate change appear poised to increase, particularly in the higher-emissions scenarios. Our assessment identifies remaining modeling uncertainties but also robustly shows that renewed policy efforts are needed to meet the goals of the Convention on Biological Diversity.

Integrated assessment models that incorporate biodiversity and ecosystem services could be an important tool for improving our understanding of interconnected social-economic-ecological systems, and for analyzing how policy alternatives can shift future trajectories towards more sustainable development. Despite recent scientific and technological advances, key gaps remain in the scientific community’s ability to deliver information to decision-makers at the pace and scale needed to address sustainability challenges. We identify five research frontiers for integrated social-economic-ecological modeling (primarily focused on terrestrial systems) to incorporate biodiversity and ecosystem services: 1) downscaling impacts of direct and indirect drivers on ecosystems; 2) incorporating feedbacks in ecosystems; 3) linking ecological impacts to human well-being, 4) disaggregating outcomes for distributional equity considerations, and 5) incorporating dynamic feedbacks of ecosystem services on the social-economic system. We discuss progress and challenges along each of these five frontiers and the science-policy linkages needed to move new research and information into action.

Integrated assessment models that incorporate biodiversity and ecosystem services could be an important tool for improving our understanding of interconnected social-economic-ecological systems, and for analyzing how policy alternatives can shift future trajectories towards more sustainable development. Despite recent scientific and technological advances, key gaps remain in the scientific community's ability to deliver information to decision-makers at the pace and scale needed to address sustainability challenges. We identify five research frontiers for integrated social-economic-ecological modeling (primarily focused on terrestrial systems) to incorporate biodiversity and ecosystem services: 1) downscaling impacts of direct and indirect drivers on ecosystems; 2) incorporating feedbacks in ecosystems; 3) linking ecological impacts to human well-being, 4) disaggregating outcomes for distributional equity considerations, and 5) incorporating dynamic feedbacks of ecosystem services on the social-economic system. We discuss progress and challenges along each of these five frontiers and the science-policy linkages needed to move new research and information into action.

The rapid urbanization in Africa profoundly affects local food and ecological systems. According to earlier research, urbanization may cause food production and biodiversity losses as agricultural or natural lands are absorbed by expanding cities. Land-use displacement effects may buffer agricultural production losses or may lead to additional biodiversity losses but are often overlooked. Moreover, impacts of dietary changes associated with urbanization are rarely considered. To address this, we combined spatially explicit projections of African urban area expansion with observed rice consumption shifts to inform a partial equilibrium model (the Global Biosphere Management Model). We demonstrate the importance of displacement effects to identify potential food production or biodiversity issues until 2050 and argue for their integration in land-use planning and policymaking across spatial scales. We identify that because of agricultural displacement, the impact of urban area expansion on food production losses is probably limited (<1%)—at the cost of additional losses of natural lands by 2050 (up to 2 Mt). We also show that considering dietary shifts associated with urbanization increases rice consumption, production (+8.0%), trade (up to +2 Mt of required import) and agricultural methane emissions (up to +12 MtCO2-equivalent yr–1), thereby underscoring the need for a systems approach in future sustainability studies.