Reusing by-products is an important strategy to ensure the preservation of natural capital and climate change mitigation. This study aimed at evaluating the potential of cork granulates, a by-product of winery industry, as an organic carbon (OC) source for the treatment of hydroponic wastewaters. First, chemical characterization was performed and discussed. Secondly, batch studies were performed using synthetic hydroponic wastewater to understand the role of particle size (PS), pH and contact time (CT) on the release of OC. The suberin is the major compound, representing >50%. It was noticed that a variance on the content of suberin across species, within the same species and depending on the extraction part (belly, cork and back) could be expected. >60% of the sample is composed by carbon while <1% was nitrogen (high C:N ratio), indicating a low risk of releasing organic nitrogen. The statistical results suggested that the main effect of PS on the release of OC is greater than both, CT and pH. The chemical release of OC gets slower with time, being this effect greater as the PS increase. Moreover, estimations showed that using the 4 mm PS, the amount of water treated would be twice the amount if the 8 mm PS had been used. The PS seems to play an important role at design nature-based solutions (NBS) focused on denitrification. The surface response methodology indicates a significant negative interaction between CT and PS suggesting that the mathematical model could be used for further optimization studies. The reuse of organic by-products as filter media seems to be an economic and environmentally friendly alternative to enhance denitrification in NBS, while preserving natural capital. However, further real scale and long-term experiments are needed to validate cork's potential as an "internal" OC source for NBS.

In the context of historical districts becoming a key to the urban transformation and high-quality development of Chinese cities, this paper investigates the regeneration of historic environments in China, emphasizing the creation of public value through urban morphology. By analyzing five distinct case studies—Chengdu KuanZhai Alley, Shanghai TianZiFang Alley, Guangzhou EnNing Road, Taiyuan ZhongLou Street, and Beijing NanLuoGu Alley—this study explores the relationship between urban form and public value creation from 2000 to 2020. The research posits that the spatial attribute of “public nature” is central to the regeneration process, highlighting the importance of understanding how urban spaces can foster community engagement and social interaction. An evaluation system is constructed to assess the regeneration of historic areas based on spatial “publicness” and people’s perceptions, addressing the need for a more nuanced approach to urban planning. The findings reveal that effective urban regeneration not only preserves historical significance but also enhances the quality of public spaces, thereby contributing to social equity and cultural integrity. This study aims to provide valuable insights for urban planners and policymakers, advocating for a public value-oriented approach to the renewal of historic districts that balances economic development with the preservation of cultural heritage. The integration of public value concepts into heritage management is crucial for creating vibrant urban environments that resonate with community needs and aspirations.

This research presents a methodological process for selecting the most appropriate construction technique for the reconstruction of housing after a seismic disaster in a rural and heritage context. This process, which is applicable to a large part of the Andean region, incorporates sustainability criteria to guarantee the economic, social and environmental balance of the intervention. The methodology was developed on a case study: the Colca Valley in Arequipa, Peru. In 2016 an earthquake affected this zone, where traditional unreinforced earthen buildings suffered serious damage. The objective of this research focuses on comparing six traditional building techniques strongly related to self-building: four techniques for adobe housing—reinforced with cane (CRA), wire mesh (WMRA), geogrid (GRA) and halyard ropes (HRRA)—and two techniques for masonry buildings— confined (CM) and reinforced (RM). For this purpose the authors used the Integrated Value Model for Sustainable Assessment (MIVES), a Multiple Criteria Decision Analysis (MCDA) model used to compare alternatives by assigning a “sustainability index” to each evaluated construction technique. This research study includes two types of variables: quantitative, such as economy ($/m²) and environmental impact (kgCO₂/m²), among others, and qualitative, such as perception of safety, respect for the urban image and popular knowledge. The research results show that reinforced adobe techniques are a viable and competitive option, highlighting the cane reinforced adobe technique (CRA), with a value of 0.714 in relation to industrialized materials such as masonry. This technique has the same safety characteristics, but at almost half the price, with the additional advantage of using traditional materials and construction methods, having less environmental impact and showing better thermal performance in cold climates.

Phosphorus (P) is a limited resource and can promote eutrophication of water streams and acidification of oceans when discharged. Crushed autoclaved aerated concrete (CAAC), a by-product from demolition, has shown great potential for recovering P. The potential of CAAC to be used in nature-based solutions as a P-reactive filter medium was evaluated by performing preliminary batch essays. Here, we evaluated the interactions and main effects of the initial concentration of P (P_i; 5, 10 or 20 mg L⁻¹), particle size (PS; 4 or 5 mm) and contact time (CT; 60, 180, 360, 720 and 1440 min) upon the removal. We performed physical and chemical characterization to understand the removal processes. Data collected were fitted in adsorption kinetic models. The statistical analysis showed a significant interaction between CT and P_i, with the combination of its main effects stronger on P removal than each one separately. Intriguingly, we noticed that the higher the concentration of P_i, the faster and higher the removal of P. Contrary to expectations, PS 5 mm showed higher removal rates than PS 4 mm, indicating that besides adsorption, other unidentified chemical processes are in place. Further studies using columns/pilots with real wastewater are recommended for a future follow-up.

This study, grounded in the theory of public value, explores how spatial form, urban governance, and people’s experiences influence the realization of public value in the regeneration of historic environments (HER) in China. Addressing the current dilemma faced by historic districts between “destructive construction” and “frozen preservation”, this research proposes that integrating public value into the HER process is crucial for promoting sustainable urban development. This study reviews key theories of public value and critically evaluates their application in historic environment regeneration. From a public perception perspective, this study constructs a hexagon public value model encompassing intrinsic, instrumental, and institutional values, analyzed through the dimensions of spatial form, urban governance, and people’s experiences. Through an empirical analysis of five case studies in China (Chengdu Kuanzhai Alley, Shanghai Tianzifang Alley, Guangzhou Enning Road, Beijing Nanluogu Alley, and Taiyuan Zhonglou Street), this research employs structural equation modeling (SEM) to examine the interactions between these factors. The results reveal that spatial form has a significant positive impact on intrinsic value, while urban governance and people’s experiences have significant positive impacts on intrinsic, instrumental, and institutional values. The methodology combines bottom-up (based on grounded theory analysis of online user reviews) and top-down (literature review) approaches, ensuring the authenticity and theoretical depth of the questionnaire. The findings offer in-depth understanding and practical guidance for future HER work, contributing to bridging the knowledge gap in this field and providing a reference for urban managers and planners to balance preservation, development, and public interests in historic environment regeneration.