Climate change and biodiversity crises are rooted in the narrow set of utilitarian values that are prioritized in current policymaking processes. Therefore, recognizing the plurality of nature’s values is a key step to enable a transformative change towards sustainability. In this work, we aim to explore the diversity of nature’s values and ecosystem services (ES) perceptions expressed by the citizens of the Venice lagoon, Italy. The 965 complete responses obtained from our survey revealed a diversity of values, with almost half of the respondents mentioning a combination of two or more values of nature, including intrinsic, relational and instrumental ones. The perceptions expressed on ES allowed to divide the sample into four clusters, which recognize the importance of the lagoon’s ES to different extents. Interestingly, these distinct ES perceptions are associated with different priorities in terms of nature’s values, and can be positioned along a gradient ranging from high to low alignment with sustainability principles. These results convey two key messages. First, part of the local community already recognizes the high importance of the lagoon’s ecological structures, processes and ES, and holds values aligned with sustainability principles. These perspectives and values should thus be recognized and embedded in the local decision making processes. Second, the citizens that currently fail to recognize the importance of ES are those to which the greatest efforts should be directed, to promote a shift towards sustainability-aligned values and behaviours. Understanding how ES are perceived complements existing ES assessments providing insights on which ES categories are poorly recognized, and can help to envisage new ways to convey their importance to the public and decision makers. From a leverage points perspective, working in these directions means to act upon crucial value-centred leverage points that can enable a transformative change towards a sustainable use of natural resources.

The recently approved Nature Restoration Law (NRL) sets targets for urban green space and tree cover. Concurrently, the proposal for an amendment to the EU Regulation on Environmental Accounts includes accounts for ecosystem extent, condition, and services for urban ecosystems, aligning with the UN Statistical Standard for Ecosystem Accounting (SEEA-EA). The NRL anticipates increased urban green space and tree cover in each Member State until satisfactory levels are achieved. However, it remains unclear what defines a satisfactory level and how it will be evaluated, though it is expected to relate to optimal or good ecosystem condition as outlined in SEEA-EA. Here, we benchmark Italian urban ecosystems in terms of extent, condition, and services against European counterparts. Hopefully, initiating a discussion to better understand potential satisfactory levels. We conduct an overall comparison and a closer look at countries with similar climates and population size. We develop thematic urban ecosystem accounts for the latest year available in Copernicus data (2018). Specifically, we create accounts for ecosystem extent, four condition variables (green space, tree cover, imperviousness, and particulate matter (PM) concentration), and air filtration as an ecosystem service. Results show that Italian urban ecosystems have slightly more artificialized areas and fewer (peri)urban forests than the EU average. In general, condition variables and air filtration efficiency in Italian urban ecosystems are similar to European averages. However, PM_2.5 and PM₁₀ in Italian urban ecosystems exceed European averages by 3-7 μg/m³ (a 20% higher than the European average), varying seasonally. Italian medium-sized cities also show higher imperviousness per inhabitant and lower urban green per inhabitant than European counterparts, with regional variations within Italy. Overall, if satisfactory levels within NRL and related policies are defined as feasible general European values, Italy is unlikely to face major challenges, compared to most European counterparts, in meeting them.

Urbanization is a global mega-trend resulting from urban population growth, urban expansion and migration from rural to urban areas. Road and communication infrastructure have been improved across large parts of rural areas, and demographic projections show that upcoming urbanization will occur in peri-urban areas, as well as in small cities and interconnected towns. The distinction between rural and urban is becoming increasingly blurred; rather than two separate entities in their own right, rural and urban areas represent two ends of a spectrum, connected via numerous linkages across a rural–urban continuum. As urban forms expand into the rural realm, the extent and condition of natural and semi-natural ecosystems is increasingly threatened by human-induced pressures, while their capacity to maintain consistent supply of Ecosystem Services (ESs) is reduced, with cascading impacts on the quality of urban life. In this context, Green Infrastructures emerge as fundamental Nature-Based Solutions because they enable residents to experience multiple co-benefits through the ESs they provide, in line with a “One Health” vision.

We present a spatial analysis of ES provision and synergies/trade-offs along the urban–rural gradient for the metropolitan city of Rome. We focus our attention on two macro classes of human-induced environmental pressures that are particularly critical to the quality of life in urban contexts, namely air pollution and the Urban Heat Island effect. We found that all the selected ESs, besides a few exceptions, are provided as a bundle, which means they appear together repeatedly. On average, ES provision grows at comparable paces moving from the inner urban core towards peri-urban and rural areas. As a consequence, most densely urbanized areas were found to be ESs coldspots, that is low ES-supply areas, compared to peri-urban and rural areas. These findings may support the implementation of the recent European Nature Restoration Law in urban areas.

Urban trees play a fundamental role in enhancing the liveability of our cities by providing several ecosystem services, including stormwater retention, air and water quality improvement, and heat island mitigation. However, the complex interplay between green systems and urban environments poses challenges in accurately quantifying their contributions. To estimate these interactions and forecast their effects, several highly specialized modelling tools are available. Indeed, the lack of a comprehensive and user-friendly tool that could fully characterize and describe the interactions has been noticed.

This study aims to assess the performance of three models, the drainage model SWMM, the water-stress model URbanTRee and micro-meteorological model PALM, in reproducing green systems and urban environment interactions, particularly in terms of runoff, infiltration, evapotranspiration, soil moisture, and thermal conditions.
We used a comparative analysis by parameterising the three models to the same case study, two well-monitored trees in TU-Campus, Berlin, with the same input data. The SWMM model, Storm Water Management Model, provided a high-resolution assessment of runoff and infiltration dynamics. The URbanTRee model focuses on runoff, infiltration, evapotranspiration and soil moisture dynamics. Finally, the PALM, an advanced model for atmospheric and oceanic boundary layer flow, stands out for simulating evapotranspiration, soil moisture and thermal conditions.

The model intercomparison showed the difficulties that arise due to different model interoperabilities, such as different parameterisation required, the different data formats, and the different space and time resolutions used. However, once normalized, it was possible, to determine which model best described each aspect of rainfall separation and which information got lost while applying different model scales and structures.

In conclusion, it was shown that comparative analyses among environmental models facilitate the choice, the implementation and thus the performance of these tools, resulting in a positive impact on urban planning, environmental management, and ecosystem service assessment.

In recent decades, mesophilic anaerobic digestion (AD) has been widely applied on an industrial scale for the energy valorisation of organic waste according to a sustainable Waste-to-Energy approach. Despite the numerous advantages of AD treatment, mainly the disposal of organic waste and the production of CH₄, the performance of the bioprocess can still be improved by optimising biotic and abiotic process parameters. This study evaluated the AD treatment of a mixture of two problematic wastes of predominantly urban origin, namely the organic fraction of municipal solid waste (OFMSW) and sludge from wastewater treatment plants (70% and 30%, respectively). To improve CH₄ production and yield and make the AD process more sustainable, two different strategies were compared, based on a non-conventional operating temperature (42°C) and the bioaugmentation of the microbial community in mesophilic condition (37°C), respectively. Two batch-configured experiments were conducted on a bench scale with acclimatized microbial communities monitoring CH₄ production and yield, fibre composition and microbial community characteristics. The results showed that a 5°C increase in operating temperature increased cumulative CH₄ production by 43.9%. However, bioaugmentation provided the best yields in terms of mL CH₄ production compared to the added volatile solid (VS). Furthermore, as bioaugmentation was performed at day 12 with the aim of reactivating the CH₄ process, it increased production by a further 19.2% and almost doubled the yields compared to the unaugmented condition (611.3 ± 3.2 vs 373.7 ± 28.1 mL CH₄ gVS^-1, respectively). The latter result is of particular interest for future research developments aimed at identifying strategies for recovering and enhancing the AD process in real plants, which are often subject to episodes of critical process conditions and inhibitory effects.