The circular economy concept has recently gained prominence in political debate and corporate discourse around the world as a pathway towards sustainability. The academic debate is characterised by several and sometimes very contrasting definitions of the concept. We claim here that the issue is not finding silver-bullet solutions that will simultaneously support population growth, increasing affluence and environmental resource regeneration. We argue that a clearer definition is needed for the circular economy concept, in terms of strategies, objectives, future states and stakeholders’ needs. Also, assessment methods need to be developed for keeping track of the transition towards a circular economy. Within this context, this paper establishes the need for a multi-stakeholder, multi-dimensional and multi-criteria approach for the evaluation of the transition towards a circular economy across different time and spatial scales, as well as multiple sustainability dimensions.

Green infrastructures deliver countless functions for counteracting climate change, air pollution, floods, and heat islands, contributing at the same time to water and carbon recycling as well as to renewable energies and feedstock provisioning. Properly addressing such environmental problems would require huge investments that could be decreased thanks to the further implementation of urban forests. Local administrations are designing participative projects to improve territories and their living conditions. The i-Tree Canopy modelling tool and the life cycle assessment method are jointly applied to evaluate the potential benefits of increasing tree coverage within the boundaries of the Metropolitan City of Naples, Southern Italy. Results highlighted that tree coverage could increase by about 2.4 million trees, thus generating 51% more benefits in pollutants removal, carbon sequestration and stormwater management. The benefits are also explored and confirmed by means of the life cycle assessment method. The potential tree cover is expected to provide a total annual economic benefit of USD 55 million, purchasing power parity value adjusted, representing USD 18 per citizen and USD 99,117 per square kilometre of implemented urban forest. These results can support a potential replication elsewhere and provide a reference for the sustainable improvement of cities by expanding urban green areas.

Renewable energy communities (RECs) are alternatives toward sustainable production and consumption pathways. In 2020, Italy implemented the EU Directive 2018/2001, defining a common framework for promoting energy from renewable sources. The “Famiglia di Maria”, a foundation dealing with social issues in San Giovanni a Teduccio, Napoli (Italy), in collaboration with “Legambiente” and “Con il Sud” Foundations, released the first Solidarity Oriented Renewable Energy Community project in Italy. Therefore, by applying social life cycle assessment (s-LCA) and life cycle assessment (LCA) methodologies, this study aims to: (i) promote the dissemination of RECs in the Italian and European contexts, (ii) suggest REC scenarios for the best social and environmental solutions, and (iii) support the policymakers for sustainable local development. Some key results show that the solidarity-oriented project has already produced mature outcomes about community cohesion. In contrast, technical skills and awareness about environmental issues still need to be further developed and shared among the stakeholders. Finally, social and environmental indicators converge on the self-consumption model as a feasible alternative for energy justice, community empowerment, and economic and market competition independence.

Water resource pollution has become a global concern in recent times due to the vital role of clean and high-quality water in the survival of living organisms. Wastewater from industrial processes is known to produce various pollutants, including heavy metals. The aim of this research was to develop an adsorbent derived from the chemical modification of peanut shells for the remediation of copper contamination in water samples. The experiments were conducted by evaluating the adsorption of the copper–phenanthroline complex by the biomass through spectrophotometric determination of molecular absorption (UV-Vis). According to the applied factorial design (2³), the best adsorption conditions achieved were a contact time of 8 hours, a metal concentration of 0.1 mg·L⁻¹, and 2 g of adsorbent biomass, resulting in an efficiency of 18.50%. From the analysis of variance (ANOVA), it was inferred that the concentration of Cu²⁺ (p = 0.00001) and the interaction between contact time and Cu²⁺ concentration (X1X2) (p = 7.34×10⁻⁵) had the greatest significance in the adsorption process. Therefore, the biomass used shows potential for the remediation of copper in water samples.