Journal of Industrial Ecology最新文献

This research addresses two critical problems facing communities today: the growing demand for housing and the need to reduce material consumption to mitigate the impacts of climate change. Material production and use accounts for more than 25% of annual global greenhouse gas (GHG) emissions and must be reduced to meet the Paris Climate Agreement's 2°C target. At the same time, increasing urban populations are accelerating the demand for housing and construction materials. Strategies for supplying more materially efficient housing are urgently needed. Here, we quantify the impact of residential form on embodied emissions. Specifically, we look at the reduction potential of missing middle (low-rise multi-unit) housing, compare missing middle to single-family and mid/high-rise buildings, and identify opportunities for optimizing efficiency within forms. Forty-two new material quantifications are calculated using an ontology based on MasterFormat and UniFormat. Minimum, maximum, and most likely GHG emissions factors are used to convert material mass to CO₂eq. We observe embodied GHG of missing middle buildings varying between 5540 and 39,600 kgCO₂eq/bedroom. On average, multi-unit missing middle buildings have significantly lower embodied GHG per bedroom than single-family and mid/high-rise buildings, but variability within forms is greater than between forms, indicating a large potential to reduce embodied GHG through building design. Best-in-class design strategies include reducing substructure size and indoor parking, limiting mid/high-rise slab thickness, and choosing low-GHG insulation products. Building missing middle homes in the 1st quartile of embodied GHG efficiency with minimum insulation emissions factors could reduce future embodied residential emissions in Ontario, Canada by 46.7%.

Tin is an important metal for society with a high risk of supply disruptions. It is, therefore, classified as a critical material in many parts of the world. An exception is the European Union, for which tin was classified as a non-critical material in 2023. However, there are many discrepancies in the literature regarding the definitions and values of the indicators used to determine tin criticality in general, and recycling indicators in particular. Values for end-of-life recycling rate (EoL RR) range between 20% and 75%, and values for end-of-life recycling input rate (EoL RIR) range between 11% and 32%. In this paper, we critically assess the circularity and criticality indicator values for tin and calculate new values using material flow analysis. The new values for tin recycling indicators are lower than those used in most previous research, with a global EoL RR of 16% and an EoL RIR of 11% in 2017. Based on the updated recycling values, combined with a highly concentrated supply, high import reliance, and difficult substitution, we argue that the European Union should classify tin as a critical material. This reclassification can lead to more policy attention for tin, which can help reduce the impact of future supply disruptions and increase the resilience of the European and global tin supply chains.

Simulation models of socio-economic metabolisms (SEM) are increasingly used to address questions regarding environmental issues. SEM studies often focus on target audiences such as researchers and decision-makers by means of scientific articles, reports, and oral presentations. In this contribution, we study the linkage of SEM models and simulation games (SGs) (i) to widen the audience of SEM research to include the general public, who, through their lifestyles, contribute to the studied environmental issues, and (ii) to address the different audiences by means of interaction tools. We illustrate the link through a case study, the postfossilCities SG. Based on the case study, existing SGs, and literature, we identified that linking SEM models with SGs can facilitate (1) the accessibility of SEM models to wider audiences, (2) the communication and understanding of systems with complex dynamics, such as nonlinear behavior, through tools that trigger experiences and emotions, (3) the consideration of actors' dimension of physical systems, and (4) the robustness of SGs by having mass- and energy-balance consistent representations of physical systems. Despite these benefits, linking SEM models and SGs is also bound to challenges, such as (1) the integration of approaches from different disciplines, (2) the high demand on time and financial resources, and (3) the balance between simplification and complexity. In order to facilitate the link between SEM models and SGs, and thus exploit the mentioned benefits, it is important to set-up connections to game-related communities and communities with long tradition of using SGs, and use existing game development methods.

The management of material flows in societies is complex yet crucial for the sustainable coexistence of humans and materials. While industrial ecology (IE) has long examined material flows, studies acknowledging their sociomaterial nature are scarce. Consequently, the existing IE research has not yet answered why materials flow in societies as they do. This study therefore examines human–material interaction (HMI) in material flows. We build on the IE and sociomateriality literature and empirical findings from a qualitative multiple-case study of two material flows (recycled concrete aggregate; biogas and recycled nutrients) where humans interact with materials to advance material flows in society more sustainably. We identify and conceptualize 11 HMI elements (adaptability, general acceptance, public interest, regulation, compatibility, consistency, degradability, availability and continuity, intensity, proximity, and re-utilizability) that further divide into three categories (human-driven, material-driven, and equally driven HMI elements) to explain in detail the manifestations of HMI in societal material flows. Together, these HMI elements explain material flows as the physical movement of materials motivated by goal-oriented humans who engage with materials, a process that leads to humans and materials becoming constitutively intertwined in spatiotemporal practice. To visualize our findings on this complex yet pivotal HMI phenomenon, we employ DNA as a conceptual metaphor. The study contributes to IE by uncovering the dynamic HMI in material flows and guiding practitioners on how to manage material flows in societies, acknowledging both human and material perspectives.

Reducing food waste could lower pressures on land resources and thereby contribute to the mitigation of global biodiversity loss. The reduction of food waste and biodiversity loss are also specified in the Sustainable Development Goals 12.3 and 15 of the United Nations. However, which supply chain stages and food products to target with policy measures is hardly known. Especially, a differentiation of the impact after sub-stages and taxa is still missing and is therefore quantified in the present study. The food waste mass at five supply chain stages and seven sub-stages in Germany was calculated and differentiated after 204 food products. All products were traced back to their countries of origin, in which their land use impact on mammals, birds, amphibians, reptiles, and plants was quantified. A new approach was developed to calculate the detailed feed demand for animal products. Germany's avoidable food waste (food that was edible before its disposal) leads to 0.3 vertebrate and 1.5 plant species being potentially lost globally. Household-level waste is responsible for 47% of this species loss, while food services show the largest impact per mass, with individual catering being as influential as one-person households. The most influential products are obtained from pigs and cattle. Among vertebrate taxa, mainly amphibians are affected, occurring in the mainly affected country Brazil. The results can be used to formulate policies that target, for example, individual catering or display the impact of animal products and their feed demand.

The concept of circular economy (CE) is proposed to lead humanity toward a sustainable future. Public authorities increasingly build on CE narratives. The progress of private sector actors is key to enable more circular resource flows. Still, the world falls far short from becoming circular and large-scale implementation of CE in actual problem–solution spaces is scarce. This study sheds light into the external strategies of circular start-ups (CSUs) in building an adequate socio-institutional embedding for circular business models (CBMs) and puts the findings in the context of CE and sustainability transformations research. CSUs are a distinct group of CE-oriented actors that build and implement CBMs wholistically and from scratch. Thereby, they can directly and indirectly contribute to the creation of circular innovation systems. This study defines the common CE mission of CSUs, sets it in context of respective socio-political CE missions, and scrutinizes the roles that CSUs adopt to drive systemic CE implementation. We observe that CSUs’ strategic interventions go further than only novelty creation. This article proposes and elaborates on four roles that CSUs adopt: conveners, reinforcers, pioneers, and champions. The roles differ according to the CSU business models, stakeholders, the institutional elements that are addressed, as well as the directionalities that CSUs set. The findings are discussed considering the governance, policies, and strategic management of various directionalities in which CE innovation develops. It sheds light on inadequacies and limitations for bottom-up CE innovation in existing norms and cognition, policy, and network governance.

Returnable packaging systems (RPS) related to consumer products help to reduce problematic plastic and glass waste in supply chains. The purpose of this paper is to investigate distribution and return processes and the related cost drivers and benefits of returnable packaging with a deposit refund system in retail stores. Through the lens of the actor–network theory and based on 30 interviews with store managers, including on-site observations, we develop a research model that structures key processes of RPS and their input and output factors. By subsequently applying system dynamics modeling, we find that: (1) customers’ process satisfaction, (2) price elasticity of demand, and (3) time between repeat purchases are key variables that impact RPS’ attractiveness and performance. This research contributes to an in-depth understanding of processes within RPS as well as interdependencies between cost drivers and benefits for retailers. From a managerial perspective, these insights can enable retailers to take action based on the influencing factors for efficient operations related to RPS. Finally, this research has policy implications as it provides argumentation for the commercial benefits of RPS for retailers aside from the overemphasized cost perspectives.

The circular economy (CE) field has moved from purely conceptual research into empirical studies. However, the literature does not provide generalized conclusions regarding the overall state of CE transition in manufacturing companies. Existing studies lack a perspective in explaining differences among companies planning or already transitioning to the CE because most empirical research so far is based on single or few case studies, generally assuming that the transition to CE, once undertaken as a purpose, moves along a continuum from a linear model to a circular one. This paper identifies differences among manufacturing companies planning and transitioning to CE and conceptualizes readiness profiles along eight dimensions of change identified in the literature as essential to CE implementation in organizations. A cluster analysis of a sample of manufacturing companies from different sectors, sizes, and locations identified five readiness profiles: the laggards, the explorers, the frontrunners, the strategizers, and the information oriented. The results show that companies may follow different approaches when exploring the potential of CE in their businesses. While some companies decide to explore and experiment across all dimensions of change, others follow a more strategic or operational approach, suggesting different states in which companies find themselves. The findings offer evidence of the change happening across the manufacturing industry and how CE transition unfolds in practice, extending existing literature by providing more overall conclusions on how the transition might unfold in manufacturing companies and different states that companies might be regarding the multiple dimensions of change that should be considered.