Nature-based solutions have gained considerable policy and research attention for enhancing biodiversity and ecosystem services, which face intense pressure from urban development. Assessments of the biodiversity outcomes of nature-based solutions are, however, insufficient. A key unaddressed question is whether such biodiversity effects vary across the urban landscape. We assess whether insect biodiversity (richness, abundance and biomass) effects vary across a gradient of percentage impervious surface in three large cities (Barcelona, Sao Paulo, Buenos Aires). We focus on Sustainable Urban Drainage Systems (SUDS) which are key in alleviating flood risk and diffuse pollution associated with urban development. We examine habitats that mimic SUDS to investigate well-established habitats, to avoid the risk of underestimating biodiversity benefits arising from lags in the colonisation of recently established nature-based solutions, i.e. taking an observation approach. We do so using random stratification to select survey locations along the urbanisation intensity gradient in each city. Across all cities, NBS sites had greater invertebrate richness, biomass and abundance than control sites. Notably, biodiversity gain is greatest in more urbanised locations where biodiversity is lowest at the control sites. Our work has substantial implications for the cost-effective design and deployment of NBS interventions in urban locations in the Global North and South.

Household- and street-level greening is a key strategy for enhancing urban resilience to climate change, yet gaps persist in understanding their environmental and socio-ecological performance. To address this gap, this study aims to identify the most common household and street-scale green infrastructure (GI) types in the UK, develop a structured scoring framework for evaluating their environmental and socio-ecological performance, and determine which configurations deliver the greatest multifunctional benefits. We surveyed 112 cities and towns in England and Wales, documenting a total of over 900 sites across front gardens, back gardens, and streets. Common types of greenery included grass, hedges, container plants, street trees, and low shrubs. A five-level scoring framework was developed to assess these configurations' environmental and socio-ecological performance across five impact dimensions: air quality, cooling, flood mitigation, biodiversity, and health and wellbeing. The framework was informed by 991 peer-reviewed studies (2015-2025), expert judgement, and remote visual assessments. The results reveal a clear performance gap between single-element and multi-element configurations. At the household level, combinations of hedges, grass, and trees scored highest in pollutant reduction, cooling, and surface water management. Adding container plants or vertical green screens further improved biodiversity and wellbeing, especially in front gardens. At the street level, the highest scores were associated with configurations that included street trees, roadside grass, hedges, and shrubs. Pocket gardens further enhanced socio-ecological performance through vegetation diversity and vertical layering. These findings underscore the role of plant diversity and spatial composition in maximising the multifunctional benefits of household and street-scale greenery and emphasise that collectively these provide the most benefit when planned as a multifunctional network of GI. The study offers a replicable, evidence-based reference to support DIY and community greening and supports equity and resilience in UK residential areas.

Air pollution is one of world's largest planetary health risk factors. Nature-based solutions (NBS) have been key in integrating air quality indicators into the urban green planning and public health discourse. Despite important contributions, approaches that include multidimensional indicators into research, planning and policies are still limited. National standards for some types of air pollutants are missing, with little evidence for a threshold for health effects. To respond to these gaps, we provide an overview and guidance for air pollution indicators, using three case studies in Europe and Latin America. We discuss the importance of context, specific pollutants and vulnerable groups and suggest new approaches at finer scales. Our findings also point out that knowledge of pollutants uptake in edible plants can give a hint to potential exposure risks for humans. Our lessons learned target specific policies and are organized into three main ideas: (a) multidimensional indicators and their implications for NBS and policy; (b) plants as biological indicators and as schools’ subjects and (c) the integration of the co-benefits to manage air quality.

While extensive research has documented the environmental benefits of green infrastructure (GI), do-it-yourself (DIY) approaches that empower individuals and communities to implement small-scale green solutions have received limited attention despite their potential to democratise urban greening and foster community engagement. This study aims to systematically characterise DIY GI implementation across UK cities and analyse the costs and benefits of GI establishment. We conducted mapping of GI configurations across major UK cities using Google street view imagery and field observations, identifying 30 street-scale and 50 household-scale GI scenarios, complemented by an extensive literature review examining small-scale GI interventions. This focus on household and streetside GI provides insights into small-scale interventions, although larger spaces such as urban forests, parks and grasslands also provide benefits, they are beyond the scope of this study. A five-level scoring framework was developed for costs, space requirements, expertise levels, maintenance demands, and cost-benefits to design DIY guidance cards for GI scenarios. Our findings reveal diversity in GI adoption, with street trees and basic grass combinations dominating street-scale implementations (20.8 % each), while household-scale approaches show remarkable variety ranging from simple grass-only configurations (18.5 %) to complex multi-feature systems. The analysis identified a linear relationship between higher GI establishment costs and increased maintenance costs, despite greater variation in the latter. The detailed DIY score reveals that household-scale combinations have greater variation in cost and higher potential benefits compared with street-scale interventions, which remain clustered at lower scores despite higher space demands. The DIY framework enables local authorities and households to make informed GI decisions, addressing key implementation barriers. Aligned with UK policies for GI, the current framework can be further enhanced through interactive platforms, planting schemes, and added metrics for biodiversity and climate adaptation.

Nature-based Solutions (NbS) are cost-effective interventions that restore natural cycles while delivering environmental, social, and economic benefits. However, selecting appropriate biophysical evaluation methods remains a challenge, particularly in data-scarce urban contexts. Existing methodologies often lack guidance on method selection based on local data, resources, and technical constraints. To address this gap, this study develops a Decision Support Tool (DST) for selecting biophysical evaluation methods for urban NbS at neighborhood, block, or district scales. The DST is based on a systematic literature review (SLR) of 256 studies, which identified the most widely used methodology-empirical equations, computational tools, and monitoring systems-along with key constraints such as budget, timeline, data availability, and technical expertise. Using this analysis, decision rules were established to guide method selection under different resource conditions. DST comprises three components: (i) a feasibility analysis for NbS selection, (ii) a decision-making framework for biophysical evaluation method selection, and (iii) an ecosystem services index for scenario comparison. The methodology was tested in Bogota, Colombia, within the "El Reencuentro" urban renewal project. Results highlight the importance of urban forests in delivering ecosystem services and demonstrate the suitability of simpler methods in resource-constrained settings. By adapting biophysical evaluation approaches to local conditions, this study provides a practical framework to support NbS implementation in urban planning.

Latin America, where over 80% of the population lives in cities, faces urgent challenges in supporting biodiversity, strengthening climate resilience, and fostering urban well-being and social cohesion. Nature-based solutions (NbS) offer a valuable approach to addressing these socio-environmental issues. However, NbS remain largely driven by Global North perspectives and its development in Latin American remains a question. In this research, we examine how NbS are being integrated into urban policies and plans through four case studies in Bogotá (Colombia), Buenos Aires (Argentina), Santiago (Chile), and São Paulo (Brazil). We combined a literature review, to assess how NbS are theoretically conceptualized and perceived in the region, with an analysis of official policy documents, to identify how the concept is being incorporated into local planning. We then analysed both datasets together to understand what NbS integration in urban policies should entail in the region. Our findings show that NbS integration is still at an early stage, with clear disparities in the policies between global and local agendas. Greater efforts and practical experiences are needed to align the concept with local realities and to strengthen its role in policy discourse. To respond to this gap, we identify five key factors that can support both the integration and advancement of NbS in Latin American urban policies and serve as guidance for other cities in the region. We conclude that advancing NbS in Latin America requires a systemic, context-specific approach, grounded in local knowledge and priorities, and sustained through joint efforts and political commitment.

Understanding landscape fragmentation is crucial to explore comprehensive land-use–land-cover (LULC) change within fast-growing urbanisation. While LULC change is a global concern, limited research explores landscape fragmentation along river and road infrastructure in high-density riverine contexts. This study addresses this gap through understanding dynamic landscape fragmentation patterns to track LULC in the Ciliwung River, Indonesia, from 1990 to 2020. The research employed remote sensing, GIS, R programming with Landsat data, Normalised Difference Vegetation Index (NDVI) values, buffering, and landscape metrics. The findings show minimal fragmentation was concentrated downstream near Jakarta, while significant fragmentation, manifesting as green loss, occurred in the midstream. Buffer analysis showed high green loss in the upstream segment both near the river and roads, particularly within a 0–400 m buffer. However, landscape metrics identified changes in the midstream close to the river buffer (0–200 m) indicating that riparian green spaces in this area persist as relatively large but ecologically unconnected “chunks”. The stability of these remaining patches makes them a crucial asset for targeted restoration. These findings contribute to a deeper understanding of how river and road networks influence the change, highlighting the integral role of remote sensing and GIS in monitoring LULC change for natural preservation.

Nature-based solutions (NbS) have emerged as a key approach to address the increasing socio-environmental challenges of urban areas. Despite their co-benefits, such as climate regulation and biodiversity enhancement, conventional engineering solutions dominate urban environments. To address this imbalance, living lab (LL) projects - with their multi-stakeholder and experimental approaches - have been widely promoted as stepping-stones for the co-creation and uptake of NbS. However, their potential and intentions for broader impact remain insufficiently understood. This study explores how LLs are designed and implemented to support NbS adoption and foster socio-technical transitions in Europe, where both NbS and LL are more developed, and in Latin America, where these specific concepts are less commonly used. Drawing on six urban LLs in Barcelona, Bogot & aacute;, Buenos Aires, Santiago, Turin, and Lisbon, this article investigates the underlying institutional motivations of key actors, the formal objectives of each LL, and the planned and implemented activities as these aspects shape the capacity of LLs to establish NbS. Based on an in-depth document review and semi-structured interviews with key actors, this study aims to advance the understanding of LLs as vehicles for change. The findings reveal differences in the design and implementation of NbS LLs in Europe and Latin America, with a higher desire for transformative change found in the latter. Additionally, they highlight the potential of NbS LLs to contribute to broader sustainability discourses and identify ways to enhance their impact.

Traditionally, the planning, investment, management, and evaluation of combined sewer networks has been the domain of hydraulic modelling using narrowly defined indicators associated with spill frequencies, flows and waterbody environmental quality standards. Due to concerns about the increasing frequency and impact of combined sewer overflow (CSO) ‘spill’ events, many cities and citizens are realising or reassessing the problems that accompany these systems, and considering alternatives including nature-based solutions (NBS). We report on an investigation of the impacts of urban stormwater management and CSOs, addressing key issues of framing, assessment and measures of success. With increasing interest being directed towards NBS for urban water management, we asked the questions: Which additional or alternative measures of success might be applied to judge the success or otherwise of different approaches? What outcomes are viewed as beneficial or problematic, what benefits should be optimised and what adverse impacts should be designed out? Reflecting on recent impact assessment guidance and drawing on research in a city with a globally leading reputation for innovation and ecological sustainability practices (Berlin), we explore how the conceptual, practical and methodological frameworks might evolve over time. Factors affecting investments in stormwater management, whether involving conventional hard infrastructure or using NBS, go well beyond simple measures of flow, storage, volume and frequency. Public notions of value and legitimacy in urban water management are changing fast. We conclude with recommendations as to how city stakeholders may together develop more comprehensive assessments of combined sewer impacts and stormwater management practices.

Nature-Based Solutions concepts and practices are being used worldwide as part of attempts to address societal challenges but have also been criticised for not dealing with deeper transformations needed to face urgent issues including biodiversity loss, climate change and inclusion. In this paper, we explore how an inclusive, integrated and long-sighted approach, emphasising a more radical integration of nature within cities, might support the transformations needed to endure major contemporary challenges. Addressing important emerging critiques of Nature-Based Solutions, we consider the potential of a more incisive form of Nature-Based Thinking (NBT) in cities, based on more holistic perspectives. The paper draws on a reflective and iterative research process that engaged both the research and practice communities through a symposium and a series of futures workshops that together explored the potential of NBT to develop future nature-cities relations in Europe and Latin America. The results of the reflective process suggest that notions of nature with people —not for people— new organisational structures, and the intention and capacity to apply long-term perspectives, are needed when planning for NBS interventions aimed at sustainable urban development. This includes developing a cultural-structural change based on new and inclusive understandings of human–nature relations, and novel governance paradigms that allow cross-sectoral coordination and engagement of local stakeholders beyond formal organisational structures.

The potential of urban nature-based solutions (NBS) to provide significant benefits to citizens and to address societal challenges is undervalued, yet the valuation of NBS impacts remains contentious. Further development of monetary and non-monetary valuation of the costs and benefits of urban NBS is required, and effective knowledge exchange on these themes is required at the international level. However, an important gap in research relates to the uptake and application of existing techniques for monetary valuation. This research explored how monetary values of urban NBS are assessed, and how NBS valuation is viewed by city government authorities in particular. Results are presented from a review of peer-reviewed articles reporting urban NBS valuation techniques development and application. Over 200 articles relating specifically to urban NBS interventions were reviewed. The literature indicates that many valuation techniques have been researched, but most studies tend to address just a few indicators of NBS impacts, which are mainly physical-environmental in their focus. To generate deeper insights into perceptions of monetary valuations in NBS impact assessments and their application, focus groups and semi-structured interviews were conducted with local and regional government staff in seven cities in Latin America and Europe. Although a wide range of economic valuation tools exist and can be applied to support NBS development, limited evidence was found for their uptake and application in practice across the contexts examined. We discuss potential reasons for limited uptake, which may include overburdensome data demands, incommensurability with existing decision-making and accounting practices, and limited staffing, financial and technical capacity - even within large cities. Results suggest that successful NBS interventions may portray economic impacts, but NBS propositions should not depend upon monetary valuations alone; social and ecological criteria remain centrally important. Participatory impact assessment methods may support improved business cases and monetary valuations for urban NBS.

The last decade has seen a profound increase in the development of assessment frameworks for ecosystem services, green infrastructure and nature-based solutions (NBS). This has improved understanding of NBS impact assessment, including processual aspects related to participatory planning and governance. We argue that, although representing a move in the right direction, NBS assessment frameworks would benefit from a broader framing of governance, including the role of government-led laws, policies and regulations along with community-led and collaborative multi-stakeholder initiatives. The consideration of marginalised communities and environmental justice should also be strengthened. To ensure a feasible and comprehensive approach to NBS governance assessment, we carried out a systematic literature review on the topic of urban NBS governance. Using thematic analysis, we developed a framework of five themes encompassing nine governance dimensions, of which some are further broken down into sub-dimensions. To assess the different NBS governance dimensions, we developed a tool in the format of a survey for urban decision-makers and other stakeholders, encompassing nine urban NBS governance indicators corresponding with the identified dimensions. Further to complementing NBS governance assessment approaches in important ways, we were able to highlight knowledge gaps around integrating features of the planning process and community-based or traditional knowledge. Our tool for monitoring urban NBS governance is simple to use and provides cities with a low-cost and comprehensive approach for monitoring and evaluating their readiness for mainstreaming NBS.

Impact assessment is a key step in mainstreaming urban nature-based solutions (NBS). Yet, it remains unclear if and how assessment frameworks influence urban planning, design and management. We contend that the potential of current NBS assessment frameworks is not fully exploited due to: (1) limited contextualisation of monitoring and assessment to place-specific contexts and (2) the depoliticisation of co-production. To address this, we present a practical five-step action framework to guide inclusive participation across different stages of monitoring and assessment of urban NBS, including indicator selection. Unlike previous approaches, applying selection criteria at the level of individual indicators, we also use criteria at the aggregate level of the indicator set. We conclude that participatory assessment contributes to mainstreaming urban NBS for sustainable and just cities, provided data is contextualised to local decision-making contexts and the process is designed to amplify marginalised voices.

Urbanization is a major driver of environmental change, which calls for multifunctional and comprehensive actions such as Nature-based Solutions (NbS). They are "inspired and supported by nature... and must benefit biodiversity and support the delivery of a range of ecosystem services". But what nature should one aim for? We tested the hypothesis that local vegetation may not always be the best source of inspiration, as environmental changes impact both extant con-ditions and species suitability for restored ecosystems. We analyzed the megacity of Sa tilde o Paulo, where laws promote the use of species from the local Atlantic Forest biome. We trained a Linear Discriminant Analysis to classify the Brazilian biomes and predicted the biomes' correspondence considering city's vegetation cover and climate. With 80% accuracy, the model predicted cor-respondence with the Atlantic Forest in 57% of the city, while 43% is better represented by the Cerrado, a dense Tropical Savanna biome. Cerrado species are naturally adapted to higher insolation, temperature and more seasonal precipitation, and they can parallel the ecosystem services of the Atlantic Forest. To help guide NbS implementation, we consider four "urban bi-omes": Atlantic Forest, Seasonally Flooded Atlantic Forest, Cerrado, and the Seasonally Flooded Cerrado, whose dynamics seem to depend mainly on changes in the proportion of dense vege-tation cover. We then discuss possible examples of NbS in the city.Results: According to the PCA (Tables S3-S6), the main difference between the classification of the green spaces classified is the higher proportion of forest cover in those classified as Mata Atlantica, with almost any influence from other vegetation cover types (Fig. 5E). This pattern is still consistent when vegetation cover is evaluated outside the largest green spaces where the presence of even small forest patches across the urban fabric results in the Mata Atla circumflex accent ntica categoryDiscussion: The urban ecosystem restoration could benefit from such natural and dynamic pro-cesses in which the Cerrado could act as a transient urban biome in the way of restoring the urban forests through soil horizon development and species succession followed by the densification of the vegetation whenever this planting scheme is possible.

Suites of concepts and approaches have been launched during recent years to promote urban nature and greener cities. However, it is doubtable whether tinkering within the current economic and political system can provide adequate solutions. Nature-based Solutions can be seen as a new conceptual approach to the human-ecological connection, and as an outcome of an evolutionary development of socio-ecological concepts. In this Communication, we argue for drawing up inspiration by nature as an outset for the development of more sustainable and inclusive cities, balancing anthropocentric and ecocentric values and acknowledging the importance of the social and governance dimensions in a more balanced socio-ecological perspective. We call this approach Nature-based Thinking.

Much has been written about the potential contribution of citizen-science approaches to further urban environmental sustainability, and associated interventions such as nature-based solutions (NBS). Engagements between researchers and stakeholders relying on bottom-up information provision, for instance community mapping, are often purported to play a vital role in developing shared knowledge, achieving greater impact and stimulating innovation. However, relatively few studies within the realm of NBS have reported on experiences in using volunteered information, or their results. This reflects an important gap, not least because of the proliferation of proposals and bids that rely upon or integrate such methods into their approach. We report on experiences with gathering information using a ‘bottom-up’ map-based wiki tool, which effectively sought to crowd-source data, contributed by members of the public and professional stakeholders. As we approach the milestone of ‘10 years on’ from the inception of the website www.daylighting.org.uk, we reflect on our approach, the opportunities presented, constraints encountered, progress made and results delivered. This is contrasted with other resources and data-gathering projects having similar aims for different urban NBS. Findings are presented on the substantive issue of the uptake of deculverting as a particular form of NBS, including land-use contexts, scheme costs and achievement of stated objectives. Reflections are given on potential contributions of such methods in relation to other, more established approaches and new techniques in urban knowledge co-production.

The valuation of urban water management practices and associated nature-based solutions (NBS) is highly contested, and is becoming increasingly important to cities seeking to increase their resilience to climate change whilst at the same time facing budgetary pressures. Different conceptions of 'values' exist, each being accompanied by a set of potential measures ranging from calculative practices (closely linked to established market valuation techniques) - through to holistic assessments that seek to address wider concerns of sustainability. Each has the potential to offer important insights that often go well beyond questions of balancing the costs and benefits of the schemes concerned. However, the need to address - and go beyond - economic considerations presents policy-makers, practitioners and researchers with difficult methodological, ethical and practical challenges, especially when considered without the benefit of a broader theoretical framework or in the absence of well-established tools (as might apply within more traditional infrastructural planning contexts, such as the analysis of transport interventions). Drawing on empirical studies undertaken in Sheffield over a period of 10 years, and delivered in partnership with several other European cities and regions, we compare and examine different attempts to evaluate the benefits of urban greening options and future development scenarios. Comparing these different approaches to the valuation of nature-based solutions alongside other, more conventional forms of infrastructure - and indeed integrating both 'green and grey' interventions within a broader framework of infrastructures - throws up some surprising results and conclusions, as well as providing important sign-posts for future research in this rapidly emerging field.

We review published references on ‘deculverting’ (also known as ‘daylighting’) projects in the United Kingdom and internationally. The aim of the review was to assess the objectives of implemented projects and to establish where evidence exists for the purported social, economic and environmental benefits of deculverting. The outcomes highlight the need for collaboration to collate detailed information on such projects, to support the further development of evidence‐based policy. It is clear that deculverting schemes can indeed exert considerable positive impacts, including ecological benefits, reduced flood risks, recreation for local communities and a stimulus for regeneration, but that the evidence for these impacts is sparse. We conclude that improvements in policy will help to maximise these opportunities, by encouraging the implementation of good practices.

There are many approaches and tools available for `sustainability assessment'. These share a common foundation in that they take a number of base pillars, invariably including: social, economic and environmental considerations or some variant thereof. The difficulties lie in how these can be combined to make a sustainability assessment (i.e. integrating non-commensurate factors). The current consensus for this is that the information collected in the form of attributes, indicators and criteria, should be used to support discourse amongst the stakeholders in deciding on interventions that are more sustainable. A project is described that is looking at portfolios of interventions in a river corridor with the objective of improving liveability in Sheffield and how the sustainability assessment framework for this has been set up and is being applied.