Urban potential in Bio-based Circular Economy

Circular Economy (CE) will accelerate the emerging shift in resource consumption from finite to renewable and plants are key in enabling the switch as industries would opt more and more for resources with a bio-based origin.\ua0 Cities have an important role in the process not only as the main consumers of the resources but also because vegetation provides numerous intangible ecosystem services essential for the wellbeing of urban dwellers. But the urban lands are heavily burdened with present activities and ongoing urbanization. Retrofitting the now obsolete and potentially contaminated brownfields provides an opportunity to engage bio-based land uses within the city periphery. At the same time, vegetation can be incorporated with Gentle Remediation Option (GRO), an alternative and more sustainable option over common ‘dig and dump’ remediation to eradicate the contamination concern and restore soil health. ‘Opportunities of bio-based production in urban brownfields’, a Ph.D. research project, concerns with such topics aiming to investigate the possibilities and preconditions for preparing urban brownfields urban bio-based production to foster a bio-based circular economy in the cities. This literature review is performed as part of the research effort to support and capture the wider scope of the project. The review work is focused on outlining the topics, ‘CE’, and ‘urban brownfields’; and establishing a common ground merging these topics from where the rest of the research work can be based on. The novel concept (i.e. CE) are explored in this literature review together with the well-established topic (i.e. brownfields) to set the backdrop and their common subsets (i.e. cities in CE, urban land potential in bio-based CE) are further investigated to guide the review in delivering information necessary for the future project work. Urban Greenspaces (UGSs) and the ecosystem services (ESs) that can be derived from them are discussed as consecutively the potential bio-based land uses and the bio-based products in an urban setting. 14 UGSs are additionally explored to better understand the scope of ESS in the cities

Repurposing brownfields as urban greenspace with gentle remediation options: A circular outlook

Circular Economy (CE) is regarded as an efficient strategy to address the challenges arising from the linear ‘take-make-use-dispose’ system of exploitation of resources. Urban land and soil are among the most exploited resources wherein brownfields, the potentially contaminated and currently obsolete land, can be considered the waste of the linear land use system. Recent CE policies and action plans acknowledge soil as a finite resource and set out clear directives for circular management of both soil and land. Brownfields pose possibility to integrate Urban Greenspaces (UGS) in increasingly denser cities to provide a range of Ecosystem Services (ES) and are instrumental in ensuring the liveability of cities. To manage risks posed by contaminants present at these brownfields, UGS can be combined with Gentle Remediation Options (GRO). Gentle remediation options are remediation strategies involving plants, fungi, bacteria, and soil amendments for managing contamination risks and simultaneously improve or at least maintain the soil quality. The overall aim of this PhD project is to develop adequate tools and methods to facilitate bringing brownfields back in use by combining UGS and GRO. This thesis presents four studies: i) a framework for identification of different UGS at a brownfield, ii) a framework for identification of potential GRO strategies for a site, iii) a working process for stakeholder analysis to explore their interests, resources, and challenges related to different UGS at a site, and finally iv) a framework to support the exploration of combining UGS and GRO on a brownfield and which integrates the tools and methods in the aforementioned studies.. The final framework is demonstrated in the case study site Polstj\ue4rnegatan in Gothenburg, Sweden, and challenged in a workshop with relevant stakeholders. The necessity of such an approach is validated as it can potentially increase the value derived from the depreciated brownfields progressively and it can support the formulation of long-term goals for sites. \ua0Some additional needs are also identified to support the practical application of the framework and they are: procedures to monetise the value generation over time, tools for estimating the time required for risk reduction with GRO (and thus the cost), and tools for selecting suitable plants, bacteria, fungi and soil amendments for more detailed site desig

An Assessment of the Potential for Bio-based Land Uses on Urban Brownfields

Circular Economy (CE) is expected to accelerate the emerging shift in resource consumption from finite to renewable, and plants are key in enabling the switch as industries would opt more and more for resources with a bio-based origin. Cities have an important role in the process not only as the main consumers of the resources but also because vegetation provides numerous tangible and intangible ecosystem services essential for the wellbeing of urban dwellers. But the urban lands are heavily burdened with present activities and ongoing urbanisation. Retrofitting obsolete and potentially contaminated brownfields within the urban periphery provides an opportunity to engage in bio-based land uses. At the same time, vegetation can be incorporated with Gentle Remediation Option (GRO), a possible alternative and more sustainable option over common ‘dig and dump’ remediation to manage risks due to contamination and restore soil health. The overall aim of this thesis is to identify bio-based land use opportunities on urban brownfields and to develop appropriate decision support to assess the potential for their realisation. This thesis presents a framework for assessing the bio-based land use potential on brownfields consisting of three practical tools: a conceptualisation of linkages between GROs and prospective Urban Green Space (UGS) uses, a scatter diagram for the realisation of 15 UGS opportunities on brownfields, and a decision matrix to analyse the requirements for UGS on brownfields. The decision matrix tool is applied to the case study site Polstj\ue4rnegatan in Gothenburg, Sweden, where six potential UGS uses are filtered out for the site. The assessment of bio-based land use potential on urban brownfields can be further improved by incorporating stakeholder planning and governance, decision support for the site-specific applicability of GRO and GRO selection, and land use specific risk management

Evaluating contamination exposure rates in different Urban Agriculture (UA) practices

Introduction: Urban Agriculture (UA) is instrumental in instilling a degree of self-sufficiency in food production inevitable for a resilient and sustainable city. Nevertheless, urban soil can be a substantial source of contamination due to previous, ongoing or even adjacent land-use like heavy traffic, and consumption of fresh produce grown on such could be an added exposure pathway for the urban population. These concerns lead many countries to follow strict regulation for gardening in urban areas bracketing it with residential use accentuating the exposure risks. But there are many UA practices with varying degree of user involvement and management; the prevalent ones taking place well-out of the residential periphery. However, there exist neither a definitive soil screening guideline that refers to such variations of UA practices nor studies on UA scenarios to modify the existing risk models.Methods: This study identifies different UA scenario and compares the contamination exposure to highlight the difference of risk in them. An exposure risk model is created combining with UA scenario sensitive parameters to test on five different practices; house garden, allotment garden, neighbourhood greenspace, meadow orchard and arable land. The scenario exposure data is to be collected from surveying different UA practice group in Gothenburg, Sweden. \ua0Results: The preliminary result with elicited data shows that practices with residential or extensive use such as house garden, neighbourhood greenspace and arable land predictably have high risk.\ua0 More common UA uses such as allotment gardens are much less risky when exposed to the same concentration of contamination while dropping to almost none for meadow orchards.Conclusion: Retrofitting abandoned, and derelict lands allow UA to find a place in the competitive urban land market. More knowledge on the exposure from soil contamination from different UA practices would provide more options to bring back obsolete land in use

COLLECTIVE DECISION MAKING OF THE COMMUNITIES IN SELECTING A FARMING STRATEGY IN THE SOUTH WEST COASTAL ZONE OF BANGLADESH : ANALYSIS OF VARIOUS STATES OF A TRANSFORMING SOCIAL-ECOLOGICAL SYSTEM (SES)

University of Tokyo(東京大学

Transforming brownfields into urban greenspaces: A working process for stakeholder analysis

Urban greenspaces (UGS) provide a range of ecosystem services and are instrumental in ensuring the liveability of cities. Whilst incorporating UGS in increasingly denser cities is a challenge to planners, brownfields form a latent resource with the potential of being converted into UGS. Transformation of brownfields to greenspaces, however, requires engagement of a variety of stakeholders, from providers to users. The overall aim of this study was to support effective and realistic realisations of UGS in the context of urban brownfields’ regeneration and stakeholder engagement. A working process was developed to: 1) integrate methods relevant for UGS realisation for a) identification and categorising of relevant stakeholders, b) mapping their interests and resources, c) identifying various challenges, and d) matching those challenges with the mapped resources over the timeline of UGS development; and 2) apply these methods to assess relevance and shortcomings. The methods were applied to a study site in Sweden, and data was collected using a questionnaire survey. The survey received 31 responses and the respondents’ comments indicated that the combination of several uses, especially integrated with an urban park, is preferable. Visualisation was an important component for data analysis: stakeholder categorisation was effectively visualised using a Venn diagram, and the needed mobilisation of resources among stakeholders to manage identified challenges was visualised using a timeline. The analysis demonstrates the need for collaboration between stakeholders to achieve an effective realisation of UGS and how multiple methods can be used in concert to map stakeholders, preferences, challenges, and resources for a particular site. The application at a study site provided site-specific data but the developed stakeholder categorisation, and the method for matching identified challenges with the stakeholders’ resources using a timeline, can be generalised to applications at other sites

Enhancing ecosystem services at urban brownfield sites - What value does contaminated soil have in the built environment?

Urban environments are challenged with a plethora of wicked problems in the face of rapid urbanization and land use change, not least natural capital degradation and widespread land and water contamination. Brownfields, under-used sites with real or perceived contamination, are significant urban and peri-urban land resources which, with well-designed remediation and management strategies can address these concerns. Gentle remediation options (GRO) are scalable nature-based techniques which provide significant opportunities for multi-functionality: managing risks posed by contaminants and at the same time enhance ecosystem services (ES) by improving the soil ecosystem in a low-impact, cost-effective manner. GRO align with an increasing interest in taking a holistic view on soil and land management to protect and improve the soil ecosystem for direct human benefit in the form of ES as well as for its indirect, intrinsic value as a haven for biodiversity. This short review aims to present a synthesis of ideas to raise awareness for urban planners about GRO techniques as nature-based solutions which can promote green infrastructure in the urban environment

A risk management framework for Gentle Remediation Options (GRO)

Gentle Remediation Options (GRO) are remediation measures involving plants, fungi, bacteria, and soil amendments that can be applied to manage risks at contaminated sites. Several studies and decision-support tools promote the wider range of benefits provided by GRO, but there is still skepticism regarding GRO implementation. Key issues that need to be better communicated are the various risk mitigation mechanisms, the required risk reduction for an envisioned land use, and the time perspective associated with the risk mitigation mechanisms. To increase the viability and acceptance of GRO, the phytomanagement approach implies the combination of GRO with beneficial green land use, gradually reducing risks and restoring ecosystem services. To strengthen the decision basis for GRO implementation in practice, this paper proposes a framework for risk management and communication of GRO applications to support phytomanagement strategies at contaminated sites. The mapping of the risk mitigation mechanisms is done by an extensive literature review and the Swedish national soil guideline value model is used to derive the most relevant human health exposure pathways and ecological risks for generic green land use scenarios. Results indicate that most of the expected risk mitigation mechanisms are supported by literature, but that knowledge gaps still exist. The framework is demonstrated to support the identification of GRO options for the case study site given two envisioned land uses: biofuel park and allotment garden. A more easily understandable risk management framework, as proposed here, is expected to act as a communication tool to educate decision-makers, regulatory bodies and other stakeholders for better understanding of risk mitigation mechanisms and preliminary timeframes of various GRO, particularly in the early stages of a brownfield redevelopment project

Session summary - The accelerating need for Urban Green Spaces (UGS) in cities and how to best accommodate it

Urban Green Spaces (UGS) are vegetated open spaces that provide a multitude of ecological functions that are essential for the physical and mental well-being of the citizens as well as for the urban environment. However, land is an extremely competitive resource in cities that are struggling to sustain the ever-growing urban population and UGS are constantly under threat of urban encroachment. Even the well spread out cities are pressured to densify by the more commonplace ‘sustainable dense urban neighbourhood’ approach that in turn, increases the pressure on open spaces such as UGS. But UGS are lacking both by quantity and quality in most cities to support the need of the citizen. Their shortage and inadequacy of UGS were made obvious during the Covid-19 pandemic when the quarantine restricted the mobility of the urban populace and made UGS an essential, and often time, the only outdoor element in everyday city life. As well as lacking in quality and quantity, the pandemic and the resulting extended quarantine also pushed forward the inherent social issues with UGS; such as their unequal distribution, access, ongoing privatisation, ‘green gentrification, etc. The session focus was on the multifaceted challenge for UGS management and governance and how to accommodate the growing necessity of UGS in cities that are heightened in a world with Covid-19

Circular urban land-use: Bringing brownfields back in use as Urban Greenspaces (UGS) by integrating Nature-Based Solutions (NBS)

Circular Economy (CE) takes place in a loop where non-renewable resources are in circular movements within a system of production and consumption while shifting promoting resources from a bio-based origin. Soil and land can be considered a non-renewable resource due to its extremely slow formation and recovery processes as well as providing the surface for sourcing bio-based resource input in the CE systems. A ‘Circular Urban Land-use’ concept (Chowdhury, 2020, p. 9) is proposed where brownfields i.e., contaminated and potentially contaminated land, can be considered as a resource in transition from abandonment to redevelopment and reuse. Brownfields can be transformed into Urban Greenspaces (UGS) to foster a bio-based circular economy in urban areas. UGS can also be potentially combined with Nature-based solutions (NBS) to manage the contamination risk and ensure a more sustainable transition of the brownfields. \ua0Gentle remediation methods are such NBS for low-cost, long-term methods without negative secondary impacts with potential to manage risks and improve soil ecology.\ua0 This contribution intends to present recent research outputs to assess the feasibility of UGS opportunities on brownfields across different time frames and we discuss the scope of interpreting the numerous ecosystem services provided by the UGS as bio-based products in an urban context (Chowdhury et al., 2020). Possibilities of combining GRO with UGS to support phytomanagement strategies at brownfields are also explored (Drenning et al., 2022). The contribution also intends to outline ongoing work on stakeholder engagement and development of a comprehensive work procedure for facilitating brownfield to greenspace transformation