Many cities around the world are experimenting with Nature-based Solutions (NbS) to address the interconnected climate, biodiversity, and society-related challenges they are facing (referred to as the climate-biodiversity-society, or CBS, nexus), by restoring, protecting, and more sustainably managing urban ecosystems. Although the application of urban NbS is flourishing, there is little synthesised evidence clarifying the contribution of NbS in addressing the intertwined CBS challenges and their capacity to encourage transformational change in urban systems worldwide. We map and analyse NbS approaches specifically for climate change adaptation across 216 urban interventions and 130 cities worldwide. Results suggest that current NbS practices are limited in how they may comprehensively address CBS challenges, particularly by accounting for multidimensional forms of climate vulnerability, social justice, the potential for collaboration between public and private sectors, and diverse co-benefits. Data suggest that knowledge and practice are biased towards the Global North, under-representing key CBS challenges in the Global South, particularly in terms of climate hazards and urban ecosystems involved. Our results also point out that further research and practice are required to leverage the transformative potential of urban NbS. We provide recommendations for each of these areas to advance the practice of NbS for transformative urban adaptation within the CBS nexus.

The science-policy interface on ecosystems and people: challenges and opportunities This-article has been republished with minor changes. These changes do not impact the academic content of the article.

How the concept of value is defined within ecosystem services operates as a filter through which important ecosystem features are identified by the specific benefits they provide to society and individuals. This value narrative reflects intrinsic and instrumental concepts which have been challenged by the Nature's Contributions to People approach in additionally highlighting the importance of relational values, stemming from socio-cultural and ethical dimensions of human relationships with nature and ecosystems. Perceived as important for the interface between ecosystems and society, relational values are yet to be operationalised in ecosystem assessment processes. This study addresses how this can be done by using a mixed-method approach encompassing quantitative and qualitative data and methodologies. Our study focuses on how school children aged 10-12 years in Sweden (n = 403) value forest ecosystem services, and further hints at the contextual factors that mediate their value perception. Children are an important demographic for reasons of intergenerational equity, and because of the temporal inertia of intensively managed forest ecosystems in Sweden. Our results show that students display complex notions of value encompassing intrinsic, instrumental and relational values alike, highlighting the importance of a broader discussion on the valuation of ecosystems through mixed methods approaches.

The Amazon biome is being pushed by unsustainable economic drivers towards an ecological tipping point where restoration to its previous state may no longer be possible. This degradation is the result of self-reinforcing interactions between deforestation, climate change and fire. We assess the economic, natural capital and ecosystem services impacts and trade-offs of scenarios representing movement towards an Amazon tipping point and strategies to avert one using the Integrated Economic-Environmental Modeling (IEEM) Platform linked with spatial land use-land cover change and ecosystem services modeling (IEEM+ESM). Our approach provides the first approximation of the economic, natural capital and ecosystem services impacts of a tipping point, and evidence to build the economic case for strategies to avert it. For the five Amazon focal countries, namely, Brazil, Peru, Colombia, Bolivia and Ecuador, we find that a tipping point would create economic losses of US$256.6 billion in cumulative Gross Domestic Product by 2050. Policies that would contribute to averting a tipping point, including strongly reducing deforestation, investing in intensifying agriculture in cleared lands, climate-adapted agriculture and improving fire management, would generate approximately US$339.3 billion in additional wealth and a return on investment of US$29.5 billion. Quantifying the costs, benefits and trade-offs of policies to avert a tipping point in a transparent and replicable manner can support the design of regional development strategies for the Amazon biome, build the business case for action and catalyze global cooperation and financing to enable policy implementation.