Urban Food Security and Informal Green Ecosystems in Secondary Cities: Negotiating Sustainability through the Green Optimum Economy

Urban Food Security and Informal Green Ecosystems in Secondary Cities: Negotiating Sustainability through the Green Optimum Economy | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Urban Food Security and Informal Green Ecosystems in Secondary Cities: Negotiating Sustainability through the Green Optimum Economy Sakkarin Sapu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8693626/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Urban food insecurity is an increasingly pressing challenge in secondary cities of the Global South, where fragile supply chains, rapid urbanisation, and uneven urban governance disproportionately affect low-income populations. This paper examines how Khon Kaen, a secondary city in Northeastern Thailand, developed an informal green food ecosystem that supports urban food security and ecological transition through peri-urban agriculture, informal markets, green logistics, and community-based initiatives. The study operationalises a Green Optimum Economy framework, emphasising negotiated balances between ecological integrity, economic viability, and social equity. Using a mixed-methods action research design that integrates food value-chain mapping, participatory action research, an Urban Lab approach, and tactical urbanism, the study analyzes upstream–midstream–downstream dynamics in Khon Kaen’s organic vegetable system. Empirical work involved collaboration with peri-urban producers, mobile vendors, green markets, local restaurants, school canteens, and vulnerable groups to prototype locally embedded mechanisms such as green logistics and small-scale green entrepreneurship. The findings demonstrate that informal and semi-formal food networks function as critical urban infrastructure, particularly during periods of disruption. During the COVID-19 pandemic, these networks enabled continued food access when conventional supply chains were destabilised, revealing both adaptive capacity and underlying precarity. The pandemic thus served as a stress test, exposing structural vulnerabilities and risk redistribution within urban food systems. The paper contributes by conceptualising the Informal Green Food Ecosystem in secondary cities, applying the Green Optimum Economy as a critical analytical lens beyond formal planning, and deriving insights for governing informal food systems as contested arenas of urban sustainability transitions. Earth and environmental sciences/Environmental social sciences/Sustainability Scientific community and society/Agriculture Urban food security informal urbanism green optimum economy peri-urban agriculture green logistics tactical urbanism secondary cities informal green ecosystem Figures Figure 1 Figure 2 Figure 3 Figure 4 1. Introduction Urban food insecurity is deepening across the Global South as climate shocks, accelerated urbanisation, and economic instability combine to put increasing strain on local food provisioning systems and more starkly reveal the governance failures and structural exclusions inscribed within contemporary urban food regimens (High Level Panel of Experts (HLPE), 2020, Food and Agriculture Organization (FAO), 2019). As these pressures deepen, food security can no longer be understood solely in terms of consumer access, but must also be examined through the governance of food production systems. Regulatory standards, certification regimes, and managerial requirements impose structural costs that systematically marginalise small-scale, informal, and semi-formal producers from dominant food supply chains. Second-order cities (intermediate, non-capital urban centres connecting rural areas to national and global economies) are especially disadvantaged not only for lacking the institutional capacity to deal with prolonged crisis situations (L. Riley, 2022, UN-Habitat, 2019), but also because they exist under uneven urban development trajectories that systematically exclude informal and small-scale actors through fragmented governance along extended supply chains. In these restricted urban spaces, food insecurity is less a question of total food supplies than one of access for many households, particularly vulnerable low-income communities that confront the challenge of obtaining affordable, safe, and nutritious foods in fragmented urban food systems (Crush and Frayne, 2011). In Thailand, the expansion of supermarket chains and long-distance logistics has reshaped food provisioning over recent decades; however, fresh markets, mobile vendors, and informal community networks continue to play a vital role in everyday food access (Turner and Schoenberger, 2012, Wiskerke, 2015, Jeaheng et al., 2023). The onset of COVID-19 and associated restrictions disrupted wholesale markets, transport, and retail operations, amplifying concerns about food safety, income loss, and affordability, particularly in urban areas with large populations of informal workers and peri-urban migrants (Laborde, 2020, Crush, 2020). Rather than constituting an exceptional crisis alone, the pandemic exposed structural vulnerabilities embedded in existing food systems, positioning cities such as Khon Kaen as salient sites for examining alternative modes of food provisioning. Moving beyond formal planning responses, this paper examines how Khon Kaen’s food system was supported—and partially reconfigured—through a constellation of informal and semi-formal practices that together constitute an informal green ecosystem. Over a 12-month period, the research team collaborated with farmers, vendors, local entrepreneurs, municipal actors, and community groups to document, prototype, and assess mechanisms for organic vegetable production, distribution, and consumption. This approach responds to a gap in urban food security scholarship, which has often documented informality descriptively without sufficiently interrogating its governance, power relations, or long-term implications This analysis is grounded in the construction and application of the Green Optimum Economy (GOE) as more of a critical rather than prescriptive problematic to ask how “optima” across ecological, economic, and social domains are being negotiated by informality, precarity and unequal power (S. Sapu, 2022). Rather than treating ecological initiatives as marginal or additive, the framework conceptualizes them as integral to the city’s economic and social fabric, seeking an “optimum” rather than a “maximum” balance among ecological integrity, economic viability, and social equity. In Khon Kaen, this framework was operationalized through five interrelated objectives: (1) mapping upstream, midstream, and downstream actors, (2) prototyping organic production systems, (3) supporting green entrepreneurship, (4) organizing knowledge exchange, and (5) designing governance mechanisms for an informal green economic ecosystem. While existing studies have richly documented the functions and contributions of informal food systems, much of this literature remains largely descriptive (Abu Hatab et al., 2019), offering limited engagement with the power relations, risk redistribution, and normative trade-offs that shape their operation (Crush and Frayne, 2011, J. Battersby, 2017). This paper moves beyond descriptive accounts by explicitly interrogating how informality is governed, who bears the costs of resilience, and how ecological, economic, and social “optimal” are negotiated within urban food systems (Feola, 2020, Soyinka and Siu, 2017). This paper explores how Khon Kaen’s food system was sustained—and, in part, reshaped—through unofficial and semi-official practices that may operate coolly as contested urban infrastructures through which compliance with or access to value and risk rather than as residual or temporary alternatives to formal planning (Lydon, 2015, J. Battersby, 2017, Soyinka and Siu, 2017). It asks: (1) How did peri-urban and urban communities in Khon Kaen build ecological production systems that contribute to city-scale food security? (2) What informal and semi-formal mechanisms—markets, logistics, data platforms, and entrepreneurship—link upstream producers to downstream consumers? and (3) How can the GOE framework help secondary cities conceptualise and govern informal green ecosystems as part of their broader urban transitions? By addressing these questions, the paper aims to speak not only to Thai urbanism but also to a wider audience concerned with the role of informal systems in urban sustainability transitions (A. Allen, 2017, Brenner., 2014). Figure 1 illustrates how urbanisation and urban sprawl restructure food systems through uneven spatial and economic processes that disrupt upstream, midstream, and downstream segments of the value chain. On the left, spatial expansion and logistical complexity lead to rising transport costs, intermediary mark-ups, and increased exposure to shocks such as floods, droughts, and pandemics. These dynamics are not neutral; they concentrate power and value capture among large-scale actors—such as supermarkets, wholesalers, and logistics firms—while systematically displacing risks onto small and informal actors, including SMEs, street vendors, consumers, and rural producers. The right-hand side introduces an alternative urban mechanism centred on social entrepreneurship and urban farming as a contested mode of governance and production. By reconnecting peri-urban organic farming, contract production, food possession, and urban consumption through locally embedded logistics and informal transport networks, this model seeks to reconfigure power relations within the food system by shortening supply chains, reducing dependence on intermediaries, and creating entry points for vulnerable groups. Urban farming is thus conceptualised not merely as a productive activity, but as a multifunctional urban infrastructure through which access to food, livelihoods, and ecological value are negotiated. Rather than resolving structural inequalities, the figure highlights how informal green interventions operate within—and partially contest—uneven urban development, revealing both their transformative potential and their limits under existing political-economic conditions. 2. Conceptual and theoretical framework 2.1 Conceptual Gap and Contribution Recent debates on urban food security in the Global South increasingly recognise the importance of informal and semi-formal food systems in sustaining access, livelihoods, and resilience under conditions of rapid urbanisation, climate disruption, and structural inequality (High Level Panel of Experts (HLPE), 2020, Food and Agriculture Organization (FAO), 2019, J. Battersby, 2017). Informal green practices—ranging from subsistence and smallholder organic farming to street vending, mobile markets, and community-based distribution—are often depicted as adaptable responses to exclusionary market conditions and fractured urban governance. Empirical investigations examine how these practices mediate poverty and marginality in relation to official systems of provision. (Crush and Frayne, 2011, Tacoli, 2017, Turner and Schoenberger, 2012). Within this body of work, the concept of the Informal Green Ecosystem (IGE) has emerged to capture the assemblage of actors, spaces, and practices through which food provisioning occurs beyond formal planning and regulatory frameworks. Despite its analytical value, this literature exhibits important limitations that constrain its critical and policy relevance. Yet a great deal of this literature is analytically impoverished, privileging empirical descriptions of how informal systems work while understudying the power dynamics, asymmetric regulatory capacities, and disproportionate distribution of risk that come to structure their operation over time. Informality is often venerated for its adaptability and resilience, but little is said about where value is captured, who bears the costs or risks, whether economic or ecological, and how informal actors remain structurally subordinate to dominant food regimes. First, much of the IGE literature offers rich empirical documentation but privileges description over critical analysis (Abu Hatab et al., 2019), documenting how informal systems function while offering limited engagement with the structural conditions under which they operate (Wiskerke, 2015, Jeaheng et al., 2023). Informality is frequently framed as a flexible and resilient alternative, yet this emphasis often sidelines questions of power, precarity, and uneven value capture along informal food chains (Crush, 2020). As a consequence, informality risks being romanticised, obscuring the ways in which such systems remain embedded within broader political-economic structures dominated by large-scale retailers, intermediaries, and logistics regimes. (Brenner., 2014, A. Allen, 2017). Second, the concept lacks a clear normative framework for evaluating outcomes at the urban scale. Although improvements in access and short-term livelihood gains are frequently emphasised, there is limited discussion of what constitutes a socially and ecologically desirable configuration of informal systems, or how trade-offs between sustainability, equity, and economic viability should be assessed. As a result, informal food systems are often evaluated in relative or instrumental terms, rather than through explicit normative criteria linked to urban justice and ecological limits (Antle and Valdivia, 2021, Cirone et al., 2023). In contrast, the GOE framework offers a normative and strategic lens that explicitly challenges growth-oriented and efficiency-driven models of urban development (S. Sapu, 2022). By advancing the idea of an “optimum” rather than a “maximum,” it underscores the need to balance ecological limits, economic reproduction, and social justice. This framework aligns closely with critical urban theory in its rejection of technocratic solutions and its emphasis on distributive outcomes and everyday economic practices (A. Allen, 2017). However, existing applications of the GOE remain largely abstract, offering limited insight into how such an optimum is produced through everyday practices—particularly in cities characterised by fragmented governance and high levels of informality. As a result, the framework risks privileging formal policy instruments while overlooking the informal mechanisms through which urban economies actually function—particularly in cities characterised by high levels of informality. Existing applications tend to privilege formal policy instruments and planned interventions, leaving open the question of how such an optimum can be produced in contexts where governance is fragmented, and market relations are deeply uneven (UN-Habitat, 2019, Hsu and Han, 2024). This paper argues that the separation between these two strands of scholarship constitutes a central conceptual gap. IGE research offers rich empirical insight but lacks a normative framework for assessing structural transformation, while the GOE provides such a framework but remains disconnected from the informal practices that shape urban food systems. Without integration, informality risks being treated either as a temporary coping mechanism or as an externality to be managed, rather than as a constitutive element of urban economic life and governance (Brenner., 2014, J. Battersby, 2017). The central contribution of this paper lies in bridging this gap through an empirically grounded analysis of Khon Kaen. It conceptualises informal green food systems as practical infrastructures through which a GOE is enacted, rather than as marginal or transitional arrangements. Empirically, the paper demonstrates how peri-urban organic farming, green markets, mobile logistics, and small-scale green entrepreneurship reconfigure upstream–midstream–downstream relations by shortening supply chains, redistributing value, and expanding access for vulnerable groups (Crush, 2020, Laborde, 2020). Analytically, it foregrounds informality as a contested terrain shaped by power relations, risk redistribution, and negotiated optimisation rather than as an inherently progressive alternative. By integrating the IGE with the GOE, this paper advances three contributions. First, it repositions informality as a constitutive terrain of urban governance and sustainability, rather than a residual or exceptional condition. Second, it operationalises the GOE through empirically grounded practices, showing how ecological integrity and social equity are negotiated in everyday urban contexts and intensified during moments of crisis. Third, it develops a transferable analytical framework for interpreting food-system transitions in secondary cities, where hybrid arrangements between formal institutions and informal actors are not anomalies but the prevailing mode of urban development (Tacoli, 2017, UN-Habitat, 2019). 2.2 The Green Optimum Economy framework The notion of a GOE was developed through an earlier strand of work on ecological urban futures in Khon Kaen (S. Sapu, 2022). It can be summarised as a triple bottom framework comprising: (1) Ecological optimum: enhancing ecological functions through organic agriculture, soil regeneration, biodiversity, water management, and reduced chemical use; (2) Economic optimum: ensuring the economic viability of green practices by supporting local entrepreneurship, green markets, value-added processing, and fair prices for producers; and (3) Social optimum: promoting social inclusion, equity, and well-being by integrating vulnerable groups, ensuring access to safe food, creating learning spaces, and nurturing community solidarity. Unlike mainstream “green growth” rhetoric, the GOE explicitly acknowledges ecological limits and socio-economic ceilings (Feola, 2020). It does not treat sustainability as a function of scale or efficiency, but rather as an outcome negotiated through competing demands, limitations, and power relations. In this paper, we integrate the GOE with an IGE Model (Luo and Patuano, 2023) developed from empirical work in Khon Kaen. Together, these concepts offer a systemic lens for understanding how food, ecology, economy, and social justice intersect in a secondary city. But the current articulations of GOE have, for the most part, remained conceptual, leaving too many questions unanswered about how this optimum is achieved in practice, especially in cities that are highly informalised, with governance often fragmented and markets marked by unevenness. The work of Alexander van der Jagt (2023, 2019) has been influential in reframing urban greening as a socially embedded, co-produced process, challenging technocratic, top-down approaches to green infrastructure. This literature emphasises informal practices, civic stewardship, and everyday governance as central to urban ecological transitions, rather than treating green space as a purely planned or managerial outcome. While analytically productive, this focus has largely remained within the domain of green spaces and stewardship. Building on this perspective, the present study extends the analysis to urban food systems, where green practices are directly intertwined with livelihoods, value chains, and access to basic needs. The Khon Kaen case illustrates that informal green food systems—such as peri-urban organic farming, green markets, and mobile vendors—function as everyday governance infrastructures that both facilitate resilience and reveal underlying power relations and uneven risk distribution. In doing so, the paper advances van der Jagt’s framework by foregrounding how informality functions not only as a mode of co-production, but also as a contested terrain through which urban sustainability and food system transitions are negotiated under conditions of structural inequality. 2.3 Integrating Green Optimum Economy and Informal Green Ecosystem Model This paper presents an integrated conceptual framework that combines the GOE and the IGE Model (Ta et al., 2025), treating them as mutually constitutive rather than separate analytical lenses. The GOE provides the normative and strategic grounding, challenging growth-maximising logics by foregrounding an optimal balance among ecological limits, economic viability, and social equity. It establishes a macro-level rationale for evaluating urban food systems not solely in terms of scale or efficiency, but in relation to sustainability thresholds and distributive justice. Building on this foundation, the IGE Model operationalizes the GOE at the urban scale by revealing how optimality is negotiated and enacted through everyday practices within informal and semi-formal green food networks. These networks—comprising smallholder producers, street vendors, community markets, and urban consumers (Choi et al., 2020, Martin, 2014) —function as adaptive socio-ecological infrastructures that shorten supply chains, reduce transaction costs, and redistribute access to green food beyond middle-class consumption niches. In this sense, informality becomes a mechanism of optimization , translating abstract sustainability principles into context-sensitive, place-based arrangements. The integrated framework conceptualizes urban food systems as dynamic optimization processes , in which ecological limits, economic constraints, and social needs are continuously balanced through spatial practices and informal governance. Rather than treating informality as a deviation from formal planning ideals, the framework reframes it as a productive interface where Green Optimum principles are tested, adjusted, and materialized on the ground. This synthesis thus bridges macro-level economic reasoning with meso- and micro-level urban food dynamics, offering a scalable yet grounded model for understanding and guiding sustainable, inclusive urban food transitions in cities of the Global South. 3. Methodology 3.1 Research design and epistemological approach This study adopted a mixed-methods, action-oriented research design grounded in a critical–interpretive epistemology. Rather than treating urban food systems as neutral technical arrangements, the research approached them as socio-spatial assemblages shaped by power relations, governance structures, and everyday practices. Knowledge was therefore produced not only through observation and measurement, but also through engagement, experimentation, and reflexive learning with actors embedded in informal and semi-formal food systems. Methodologically, the research combined value-chain analysis, participatory action research (PAR), Urban Lab prototyping, and tactical urbanism experiments. Value-chain analysis was used to map upstream–midstream–downstream relations and identify structural bottlenecks and asymmetries. PAR and the Urban Lab approach enabled co-production of situated knowledge with farmers, vendors, entrepreneurs, and municipal actors, while tactical urbanism functioned as an experimental method to test low-cost, temporary interventions—such as pop-up markets, community gardens, and pilot logistics routes—and to observe their socio-economic and spatial effects in real-world conditions. The project was conducted over a 12-month period and structured around five objectives: mapping and linking value-chain actors, prototyping organic production systems, supporting green entrepreneurship, facilitating knowledge exchange, and developing a management mechanism for an informal green food ecosystem. 3.2 Study area and data collection The study was conducted in Khon Kaen and its surrounding peri-urban districts in Northeastern Thailand. As a secondary city, Khon Kaen occupies an intermediary position between rural production zones and urban markets, while exhibiting high levels of informality in food provisioning and employment. Upstream sites included peri-urban organic farming communities in Nam Phong and Sam Sung districts (approximately 30 km from the city), while midstream and downstream activities focused on the Khon Kaen Green Market, mobile vegetable trucks, local organic restaurants, school canteens, and low-income urban communities. Data collection combined qualitative and quantitative methods: value-chain mapping of producers, vendors, logistics routes, and institutional consumers; semi-structured interviews with farmers, hawkers, market managers, municipal officials, restaurant owners, school administrators, and representatives of vulnerable groups; consumer surveys at green markets and community gardens; participant observation during Urban Lab events and tactical interventions; and document analysis of relevant policy documents, municipal strategies, NGO reports, and the project’s final research report. 3.3. Data collection Data were collected through: • Value-chain mapping of farmers, vendors, distribution routes, restaurants, and institutional consumers; • Semi-structured interviews with organic farmers, hawkers, market managers, municipal officials, school administrators, restaurant owners, and representatives of vulnerable groups; • Surveys of consumers at green markets and community gardens regarding their preferences, willingness to pay, and perceptions of food safety; • Participant observation during Urban Lab events, training workshops, and tactical interventions such as community garden set-ups, pop-up markets, and mobile truck routes; • Document analysis of relevant policy documents, municipal strategies, NGO reports, and the final research report itself. 3.4. Data analysis Qualitative data were analysed thematically, with codes related to informality, governance, resilience, entrepreneurship, logistics, and social inclusion (J. Battersby, 2017, Soyinka and Siu, 2017). Quantitative data from surveys and production records were analysed descriptively to quantify changes in supply volumes, income levels, and access patterns. Findings were synthesised into an IGE Model that captures the key components and relationships uncovered in the field. This model, in turn, was interpreted through the GOE framework to derive conceptual insights and policy implications (S. Sapu, 2022, Feola, 2020). 4. Context: Khon Kaen’s food system and green initiatives. Khon Kaen is a regional economic hub in Northeastern Thailand. The city has experienced rapid growth through education, logistics, healthcare, and services, while remaining closely connected to an agricultural hinterland where rice, vegetables, and livestock are produced. Organic agriculture has gained momentum in Khon Kaen city over the past decade, driven by health concerns, niche market opportunities, and the spread of participatory guarantee systems (PGS)(IFOAM, 2016, Mougeot, 2005). The Khon Kaen Green Market has become a focal point for organic and safe food, providing a weekly platform where certified farmers, safe-vegetable producers, and food processors sell directly to consumers under the oversight of municipal and public health authorities. The municipality supported the green market by allocating part of a public park for Friday evening trading and permitting the renovation of a vacant building into a daily green grocery shop. The onset of COVID-19 introduced principal stresses. Lockdowns and restrictions limited movement, reduced restaurant demand, and disrupted wholesale channels. Yet the crisis also created openings for innovation. The Khon Kaen City Development Company and local actors launched mobile “pum-puang” trucks that brought fresh food into neighbourhoods, while community groups established or revived vacant lands, small gardens, and sharing farms to support those who lost income, including informal workers and unhoused individuals. Formal market mechanisms predominantly organize production and distribution through capital-intensive supply chains, where commodity flows are structured around large-scale investments and centralized market logics. By contrast, the Informal Green Economy reconnects small-scale urban resource bases and localized cost structures, linking vulnerable populations as both producers and consumers through shorter, socially embedded circuits of exchange. This mode of economic organization challenges dominant market hierarchies by foregrounding accessibility, inclusivity, and ecological sustainability, thereby offering an alternative pathway for urban development that aligns with concerns of social equity and environmental stewardship. These overlapping initiatives formed the practical foundation upon which the project built, using research funding and design methods to connect disparate efforts into a more coherent city-wide ecosystem (L. Riley, 2022). 5. Findings 5.1 Reconfiguring the Urban Food Value Chain through Informal Green Practices (Upstream: peri-urban organic production) The study identified significant structural inefficiencies in the food distribution system. Vegetables consumed in Khon Kaen were frequently transported to Bangkok—covering a round-trip distance of more than 950 kilometres—before being redistributed back to the city. This circuitous logistics pattern substantially increased transportation costs, reduced returns for upstream farmers, and enabled intermediaries to capture a disproportionate share of value. At the same time, the findings revealed strong and growing consumer demand for organic vegetables that consistently exceeded local production capacity. This persistent supply–demand gap indicates a “blue ocean” market with considerable potential for future expansion. Empirical evidence suggests that food insecurity in Khon Kaen is more closely shaped by weak coordination across the urban food value chain than by insufficient production. Interviews with peri-urban organic farmers (comprising 86 stalls), including 33 certified organic producers, 23 safe-agriculture producers, and 30 processed-food vendors, revealed that, prior to the intervention, most producers sold their products through intermediaries or distant wholesale markets, often receiving payment 30–45 days after delivery. This delayed cash flow constrained reinvestment and increased production risk, particularly for small-scale households cultivating fewer than 5–7 plots. Meantime, consumer surveys conducted at green markets showed sustained unmet demand for organic vegetables, especially among urban households concerned with health and food safety. The emergence of informal and semi-formal green practices altered these dynamics by creating direct and semi-direct linkages between producers and urban consumers. Peri-urban farms supplying the green market and mobile distribution routes typically operate within a 30-kilometre radius, with average transport times of approximately 30–35 minutes. This spatial proximity reduced logistics costs and enabled same-day or next-day transactions, improving income predictability for producers while stabilising prices for consumers. Table 1 outlines the characteristics of the 18 producers and vendors supplying the Khon Kaen Green Market. The system is dominated by peri-urban actors, with most producers located outside the urban core, yet transport distances remain relatively short, averaging 26.9 km with a mean travel time of approximately 32 minutes. The majority of participants operate under organic standards, while others follow safe food or GAP practices. Farm sizes are generally small, ranging from home gardens to plots of up to 6 rai (9,600 square meters), with a few larger community-managed sites. Organisationally, the market comprises individual households and community enterprises, with actors occupying multiple positions along the value chain as producers, producer–vendors, and informal traders, reflecting the green market ecosystem's flexible, hybrid structure. Table 1: Characteristics of Khon Kaen Green Market Members Category Key Characteristics Number of members 18 producers/vendors Spatial location 4 urban (≤2 km); 14 peri-urban/rural Average distance 26.9 km (median 28.4 km) Transport time Avg. ~32 minutes Production standards 12 organic; 6 safe food / GAP Farm scale Small plots (home gardens to 6 rai or 9,600 Square Metter); few large community plots Organisation Individual households and community enterprises Role in value chain Direct producers, mixed producers–vendors, informal traders Source: author (2022) From a grounded perspective, these practices did not eliminate intermediaries altogether but selectively reconfigured their role. Market managers, mobile vendors, and small processors acted as relational brokers rather than price-setting middlemen. This shift redistributed value along the chain, allowing informal actors to capture economic benefits that were previously absorbed by upstream actors. Conceptually, these findings support the interpretation of informal food systems as adaptive infrastructures that reorganize value-chain relations under conditions of market exclusion, aligning with the GOE’s emphasis on optimization rather than maximization. Interviews with organic farmers reveal that “ production expansion is constrained mainly by climatic variability and recurrent hazards such as floods and drought. Limited capital prevents farmers from absorbing these risks, rendering scale-up economically precarious. Designing and planning agricultural practices that are calibrated to farmers’ livelihood costs and economic capacities may therefore offer a more viable pathway, aligning organic production with their everyday socio-economic realities. ” The project identified and engaged a network of organic and “safe” vegetable producers in the peri-urban zones around Khon Kaen. Many of these farms were family-run, combining small plots of land with labour from household members. Some were long-term organic producers, while others were conventional farmers who experimented with organic methods on part of their land. Interview findings reveal that “organic” is understood by producers not merely as the absence of chemical inputs, but as a holistic livelihood practice encompassing improved health, reduced economic risk, and strengthened social relations. Organic farming is thus framed as a relational and socio-economic strategy that integrates well-being, livelihood security, and mutual support, rather than solely a technical mode of agricultural production. It can be understood as a mode of production that aligns with the organic integrity of the household itself—reflecting producers’ aspirations for health, livelihood security, and social coherence, rather than merely compliance with technical standards. Vacant or under-utilised land, including low-lying areas, roadside verges and abandoned plots, was transformed into productive agricultural spaces. Through training and demonstration, farmers improved soil quality, reduced chemical inputs, and experimented with crop diversification, including leafy greens, herbs, mushrooms, and indigenous vegetables (Tacoli, 2017, Mougeot, 2005). Two empirically grounded case studies are particularly illustrative of the adaptive reuse of vacant urban land in Khon Kaen: (1) the transformation of residual inner-city space beneath the elevated railway into sites for vegetable cultivation, and (2) the repurposing of an abandoned suburban school campus as a source of pesticide-free food supplying the city. 5.2 Midstream Mechanisms: Green Markets and Informal Logistics as Governance Devices 5.2.1 The Green Market as a Hybrid Governance Space Field observations and interviews indicate that the Khon Kaen Green Market functioned as a central coordination node, linking approximately 80–90 vendors, including certified organic producers, safe vegetable growers, food processors, and prepared food sellers. Market access was governed through a hybrid arrangement combining participatory farm inspections, municipal food-safety testing, and peer-based accountability, rather than relying solely on formal certification. While these mechanisms lowered entry barriers for small-scale and informal producers, they also shifted responsibility for food safety and quality assurance onto producers and community networks. In organic food systems, trust is therefore an institutional outcome shaped by local governance rather than an inherent market attribute. Trust-based inspection systems, when supported by municipal recognition, can reduce certification costs and expand access to safe food, but they also raise questions about how regulatory labour and risk are unevenly distributed within hybrid food governance regimes. Consumer interviews (146 samplings) further revealed that repeated face-to-face interactions played a critical role in shaping trust. Many consumers reported learning about cultivation methods, seasonal variability, and price fluctuations directly from farmers, which in turn influenced their purchasing decisions over time. This relational process stabilised demand, particularly for small producers who lacked branding or formal certification. As one market manager noted during participant observation, “trust accumulates through presence rather than labels.” Consumers’ decisions to purchase organic products were shaped by negotiated trade-offs between certification standards and price affordability. While doubts persisted about the rigour and consistency of inspection mechanisms, the involvement of local authorities in market governance helped legitimise these arrangements. Rather than resolving regulatory gaps, these locally embedded governance structures produced forms of contingent trust that enabled consumers to accept informal standards as credible substitutes for formal certification, thereby mediating tensions among affordability, safety, and institutional oversight. Analytically, the green market functioned as a hybrid governance space, where informal rules and formal oversight intersected. Governance emerged through negotiated practices rather than fixed regulations, illustrating how informal institutions can compensate for gaps in formal food governance while remaining embedded within municipal frameworks. It can therefore be argued that local municipalities play a pivotal role in shaping locally embedded mechanisms and standards that intervene in dominant organic food market logics in everyday urban life. Through such interventions, municipal actors do not merely facilitate market functioning but actively reconfigure governance arrangements to safeguard urban residents’ access to safe food, particularly in contexts where formal certification systems remain inaccessible or exclusionary. 5.2.2 Informal Green Logistics and Mobile Distribution The project introduced and strengthened innovations in green logistics, under the label “GREEN DEE = GOOD GREEN”. Mobile distribution systems—particularly organic trucks and “pum-puang” vendors—extended the reach of the green ecosystem beyond fixed market sites. Mapping of distribution routes showed that these trucks connected peri-urban farms, green markets, residential neighbourhoods, offices, and school canteens along flexible, demand-responsive circuits. Pilot data indicated that unsold produce from weekly Green Markets could be redistributed through mobile routes, generating additional margins of approximately 20–25 percent while reducing food waste. In the initial phase of the study, an Urban Lab approach was used as an experimental platform for iterative trial-and-error. These early experiments generated empirical insights into demand patterns, constraints, and stakeholder needs, which were subsequently used as key inputs and materials for a series of participatory workshops. Then, Co-design workshops with farmers, vendors, and researchers revealed that product formats were strategically differentiated according to urban contexts. Fresh produce was prioritised for households, restaurants, and school canteens; ready-to-cook packages targeted office districts with family households; and prepared foods served single-person households and lunchtime consumers. These distinctions were not imposed top-down but emerged through iterative experimentation and feedback from vendors and consumers. These findings foreground logistics as a socially negotiated practice rather than a purely technical function. Informal logistics redistributed not only food but also risk, information, and value across the chain, reinforcing the GOE’s emphasis on balancing ecological sustainability, economic viability, and social inclusion. A two-month pilot of the Green Dee service across diverse urban settings—including low-income communities, hospitals, government offices, public parks, and schools—highlighted the distributive role of informal logistics in addressing food access inequalities. The service was particularly significant for elderly adults with limited mobility, whose everyday access to fresh, safe food is constrained by inadequate public transport systems in secondary cities. By bringing organic and safe produce directly to households, the mobile pum-puang truck effectively bypassed spatial and infrastructural barriers embedded in the formal food system. These findings suggest that mobile vendors operate not merely as market actors, but as forms of informal urban infrastructure that actively redistribute access to food, mitigate mobility-based exclusion, and contribute to food justice by extending the reach of green food systems to populations otherwise marginalised in urban planning and retail geographies. 5.2.3 Green Start-up Incubator: Entrepreneurialisation and the Neoliberalisation of Sustainability To advance the economic dimension of the Green Optimum Economy (GOE), the project established a green start-up incubator to support small-scale actors across the organic food chain, including young farmers, micro-processors, informal vendors, and community-based restaurants. Evidence from the Green Hackathon 2022, as documented in the project report, suggests that the incubator operated more as a space for exchange and experimentation than as a conventional business accelerator. Rather than fast-tracking start-ups, it enabled interaction among farmers, traders, processors, technology developers, and public agencies, allowing participants to test ideas and build networks. Of the 32 start-ups involved, 20 (62.5% of the total) operated primarily at the upstream production level, while 8 and 4 were concentrated in midstream and downstream activities, respectively. Interviews indicate that most upstream entrepreneurs worked on land inherited from their parents, but were actively experimenting with new technologies and management practices to improve productivity, resilience, and responsiveness to market demand. Among midstream and downstream actors, five also controlled land-based production assets, allowing them to combine processing, distribution, or retail activities with farming. This overlap points to an emerging form of vertically integrated green entrepreneurship, shaped less by start-up capital alone than by access to land, intergenerational assets, and the capacity to adapt innovation to local conditions. Training activities—including organic production, branding, digital marketing, and basic business planning—enabled participants to experiment with new product formats such as ready-to-cook vegetable kits and small-scale processed foods. Yet the outcomes were uneven. Only a small number of participants were able to sustain their ventures beyond the pilot phase, with many constrained by limited access to capital, labour shortages, and fluctuating market demand. Under these conditions, green entrepreneurship functioned primarily as a livelihood strategy rather than a pathway to scalable or stable growth. From a critical perspective, the incubator reflects wider processes of the neoliberalisation of sustainability, in which responsibility for ecological transition is devolved to individual entrepreneurs and communities. Rather than addressing structural constraints within food systems, such initiatives often require informal actors to absorb market risks, certification costs, and demand uncertainty. The findings suggest that green start-ups contribute meaningfully to food system transitions only when embedded within supportive configurations of markets, logistics, and public institutions; in their absence, entrepreneurial pathways risk reproducing precarity rather than advancing a durable economic optimum. In secondary cities, policies that support green entrepreneurial incubation can play a strategic role in strengthening urban food systems. Many cities in the Global South face a “missing middle” demographic pattern, as working-age populations migrate to metropolitan centres, weakening local food economies and accelerating population ageing. Supporting locally embedded green and food-related enterprises can encourage younger generations to remain in or return to their hometowns, thereby stabilising livelihoods, reinforcing food value chains, and enhancing the long-term resilience and inclusiveness of urban food systems. Interviews with young entrepreneurs who returned to their hometowns or secondary cities point to a set of overlapping, often pragmatic motivations rather than straightforward opportunity-seeking. For some, relocation followed parental illness or death, creating pressure to take over family land or businesses in the absence of successors. Others described returning after financial setbacks linked to failed investments or unstable employment in large metropolitan areas. Concerns about physical and mental health associated with urban living also featured prominently in these decisions. Taken together, these accounts indicate that return migration is frequently necessity-driven and shaped by broader conditions of labour precarity, family obligation, and uneven urban development. In this context, public policy should move beyond metropolitan-centric innovation strategies and place greater emphasis on supporting start-up incubation and small-scale entrepreneurship in secondary cities, as a means of creating viable livelihoods, redistributing investment, and expanding employment opportunities outside major urban centres. 5.3 Downstream Dynamics: Consumption, Trust, and Value Construction Downstream actors were not passive recipients but actively shaped the IGE. Survey data and interviews show that consumers prioritized affordability and trust alongside, and sometimes over, formal organic certification. Many were willing to purchase produce described as “safe” or “organic-in-practice” when relational trust with producers had been established through repeated interaction and local verification mechanisms. This form of trust-based valuation was particularly important for low- and middle-income households, for whom certified organic products sold through supermarkets remained economically inaccessible. Small restaurants sourcing green materials and mobile vendors reported increased flexibility and differentiation, enabling them to adjust menus according to seasonal availability while reducing dependence on volatile wholesale supply chains. These practices reinforced local circulation of value and strengthened producer–consumer relations beyond one-off transactions. However, interviews with midstream restaurant owners reveal a key limitation of the IGM: demand consistently exceeds supply. While the GOE prioritises sufficiency and balance over volume expansion, this orientation constrains the system’s ability to respond to sustained market demand. As a result, restaurants—particularly those with high vegetable consumption—face supply instability despite strong consumer interest. From a policy perspective, this tension underscores the need for targeted state support to expand the upstream base of small-scale producers and strengthen collective aggregation mechanisms to secure minimum production volumes. In secondary cities across Northeastern Thailand, where local restaurants form a dense and culturally embedded food economy with high vegetable consumption, such interventions are critical to aligning the principles of optimisation with the material requirements of urban food provisioning. Grounded in everyday interactions, these dynamics reveal that value in informal food systems is socially constructed and continuously negotiated. Access, affordability, and food safety emerged not solely from price mechanisms or regulation, but from relational infrastructures that link production and consumption. This underscores the limits of market-centric approaches to urban food security and highlights the importance of informal systems in mediating sustainable and equitable food provisioning. Figure 3 illustrates the IGE in Khon Kaen as a relational urban infrastructure operating across social, virtual, and physical spaces. Rather than a linear supply chain, the diagram depicts dense interconnections through which food, information, trust, and social support circulate among peri-urban producers, markets, intermediaries, and consumers. The Khon Kaen Green Market emerges as a central coordinating hub, linking upstream production with downstream consumption while facilitating feedback, learning, and redistribution. Actors such as community organisations, food banks, and local enterprises bridge physical food spaces—markets, restaurants, school canteens, and learning venues—with social mechanisms that support vulnerable groups and urban poor communities. The overlapping flows highlight how informal systems enhance access and adaptability, particularly during disruptions, while simultaneously revealing the uneven distribution of risk borne by informal actors. The figure thus reinforces the finding that food security in Khon Kaen is produced through negotiated, hybrid arrangements rather than formal planning alone. 6. Discussion: Informality, Power, and Urban Food Transitions This paper examined how informal and semi-formal green food systems contribute to urban food security in a secondary city context, and how these practices can be interpreted through the GOE framework. Drawing on empirical evidence from interviews, value-chain mapping, pilot interventions, and consumer surveys conducted in Khon Kaen, the findings demonstrate that informal green food ecosystems can enhance food access, stabilise livelihoods, and reconfigure value chains in ways that formal market systems often fail to achieve. At the same time, the evidence also reveals that informality is not an unambiguous solution, but a contested terrain shaped by power relations, uneven risk distribution, and institutional constraints. 6.1 Informal Green Ecosystems: Infrastructure and Precarity The results demonstrate that informal food systems in Khon Kaen function as critical urban infrastructure, mediating food access, trust, and coordination across upstream, midstream, and downstream actors. Green markets, mobile vendors, and peri-urban farms collectively filled gaps in formal food provisioning, particularly during disruptions such as the COVID-19 pandemic. These systems enabled small producers and informal vendors to capture greater value, while improving affordability and accessibility for urban consumers. However, these benefits coexist with forms of precarity that are often underplayed in celebratory accounts of informality. Informal actors continue to bear disproportionate risks related to income instability, labour conditions, regulatory uncertainty, and dependence on relational trust rather than enforceable rights. Resilience, in this sense, is frequently achieved through households and individuals absorbing risk rather than through structural protections. Recognising informality as infrastructure, therefore, requires acknowledging its dual character: as a source of flexibility and innovation, but also as a site where vulnerability is reproduced. 6.2 The Green Optimum Economy as a Negotiated Process The Green Optimum Economy framework offers a valuable lens for interpreting these dynamics by shifting attention away from growth maximization toward balanced outcomes across ecological, economic, and social dimensions. In Khon Kaen, optimisation did not emerge as a stable or predefined condition, but as a negotiated process shaped by everyday practices, trade-offs, and compromises. Ecological goals—such as organic cultivation and reduced chemical use—were continually balanced against the needs of livelihoods, market demand, and logistical constraints. Importantly, what counted as “optimum” varied across actors and contexts. For small farmers, optimisation often meant income predictability rather than maximisation; for vendors, it involved flexibility and reduced waste; for consumers, affordability and trust frequently outweighed formal certification. These findings suggest that the Green Optimum Economy should be understood not as a blueprint or policy endpoint, but as a heuristic device that exposes tensions between competing priorities and makes visible the politics of sustainability transitions. However, the key difference of the Green Optimum Economy lies in analytical scale and orientation. While Górska-Warsewicz’s work (2021) primarily examines structural constraints and systemic challenges within existing institutional and market frameworks—such as regulation, certification, and supply-chain stability—the Green Optimum Economy reframes these dynamics as part of a multidimensional transition pathway. It places stronger emphasis on bottom-up experimentation, spatial interventions, and the integration of informal and semi-formal practices into urban food systems. Moreover, the social dimension is more explicitly foregrounded in the Green Optimum Economy, which conceptualizes food systems as social infrastructures that integrate vulnerable groups, foster collective learning, and strengthen networks capable of responding to crises. Together, these differences position the Green Optimum Economy not as a competing explanation, but as a complementary framework that translates structural insights from the literature into an operational, place-based model for sustainable urban food transitions. These optimums are not automatically aligned. For example, organic production can raise prices, potentially excluding low-income consumers; or entrepreneurship might increase competition for small vendors. The Green Optimum Economy framework helps identify such tensions and asks how ecological, economic, and social goals can be balanced in a way that is locally acceptable and sustainable. Figure 4 conceptualises the Green Optimum Economy as an integrative paradigm that positions the household economy at the core of urban economic transformation, mediating between neighbourhood and local economies through sharing, circular, and creative economic practices. At the upper level, the household economy serves as a connective node, translating everyday practices into broader local economic circuits and enabling value creation embedded in place-based social relations. At the urban scale, the Green Optimum Economy provides a framework for advancing a green and inclusive city by aligning local economic activities with ecological and social objectives. This is operationalised through the integration of green infrastructure and nature-based solutions, which form the material and ecological foundations of urban sustainability. The paradigm emphasises locally appropriate and trust-based value chains, content-driven green products, and context-sensitive logistics tailored to specific consumer groups. Together, these elements support both passive and active income generation while reinforcing local trust, resilience, and inclusivity. By linking household practices to green infrastructure and nature-based solutions, the Green Optimum Economy paradigm articulates a transition pathway in which economic viability, ecological integrity, and social equity are pursued as mutually reinforcing rather than competing goals. 6.3 Hybrid Governance and Uneven Power Relations The Khon Kaen case highlights the emergence of hybrid governance arrangements in which municipal authorities, civil society organisations, market committees, and informal actors jointly shape food provisioning. Municipal support—through permissions, access to public land, food safety testing, and recognition of green markets—played an enabling role without fully formalising informal systems. This hybrid approach created institutional space for experimentation and inclusion. Yet hybrid governance is not inherently equitable. Decisions about market access, standards, and participation remain unevenly distributed, and informal actors often lack bargaining power when rules change or support is withdrawn. Inclusion within governance arrangements may therefore be conditional and reversible, reinforcing dependence rather than autonomy. A critical reading of hybrid governance thus cautions against treating collaboration as inherently progressive, and calls for closer attention to how authority, responsibility, and risk are allocated . 6.4 Crisis as Stress Test: Lessons from COVID-19 The COVID-19 pandemic served as a stress test, revealing both the strengths and limitations of informal green food systems. While informal networks proved more adaptable than formal supply chains in the short term, their capacity to scale and sustain support under prolonged crisis remains uncertain. In many cases, continuity depended on intensified labour, unpaid care work, and informal reciprocity, raising questions about who ultimately bears the costs of resilience. This observation challenges narratives that position informality as a permanent solution to systemic food insecurity. Instead, the findings suggest that informal systems are most effective when recognised and supported as part of a broader food governance landscape, rather than as substitutes for structural reform. 6.5 Implications for Urban Food Transitions Taken together, the findings indicate that informal green food ecosystems can play a significant role in advancing more just and sustainable urban food systems, particularly in secondary cities characterised by limited planning capacity and high informality. However, their contribution depends on how they are governed, supported, and integrated. Treating informality as a central component of urban infrastructure necessitates policies that mitigate precarity, safeguard livelihoods, and ensure that the benefits of green transitions are not achieved at the expense of vulnerable groups. By integrating the Informal Green Ecosystem perspective with the Green Optimum Economy framework, this paper presents a critically grounded approach to understanding urban food transitions—one that foregrounds negotiation, power, and everyday practices rather than idealized models of sustainability. 7. Conclusion This paper examines how informal and semi-formal green food systems function as critical components of urban food security in a secondary city of the Global South. Using Khon Kaen as an empirical case, the study demonstrates that food insecurity is shaped less by absolute scarcity than by the organisation, governance, and accessibility of urban food systems. Informal green practices—including peri-urban organic farming, green markets, mobile distribution, and small-scale green entrepreneurship—were shown to play a significant role in reconfiguring upstream–midstream–downstream relations, particularly under conditions of disruption. The findings contribute to urban food scholarship by conceptualising informal green food systems not as residual or transitional arrangements, but as relational infrastructures through which food access, value, and governance are produced in practice. At the same time, the analysis cautions against romanticising informality. While informal systems enhance flexibility and responsiveness, they also reproduce precarity by redistributing risk onto households and informal workers. Resilience, in this sense, is not cost-free, but often achieved through uneven labour burdens and fragile institutional arrangements. By integrating the Informal Green Ecosystem perspective with the Green Optimum Economy framework, the paper advances a conceptual contribution that bridges empirical groundedness with normative inquiry. The Green Optimum Economy is operationalised not as a policy blueprint, but as a heuristic for understanding how ecological integrity, economic viability, and social equity are continually negotiated within uneven urban contexts. This integration foregrounds trade-offs, power relations, and contestation as central features of urban sustainability transitions, rather than anomalies to be resolved through technical optimisation. Rather than offering a policy blueprint, the Green Optimum Economy provides secondary cities with a critical lens for interpreting and governing informal green ecosystems under conditions of uneven power and limited institutional capacity. The Khon Kaen case also underscores the importance of hybrid governance in shaping the outcomes of informal food systems. Municipal support created space for experimentation without full formalisation, yet inclusion within governance arrangements remained conditional and uneven. These dynamics highlight the need for urban policy approaches that recognise informal systems as part of core urban infrastructure while addressing structural vulnerabilities and power asymmetries, rather than treating informality as either a problem to be eliminated or a solution to be celebrated. While the findings are grounded in a single case study, their relevance extends beyond Khon Kaen. Many secondary cities across the Global South share similar characteristics: limited planning capacity, fragmented food supply chains, and high levels of informality. The analytical framework developed in this paper offers a way to interpret these conditions and identify leverage points for more equitable and sustainable urban food transitions, without assuming universal models or best practices. Future research could build on this work by examining the long-term trajectories of informal green food ecosystems, particularly their capacity to endure beyond moments of crisis and their interaction with evolving regulatory regimes. Comparative studies across secondary cities would further illuminate how different political, institutional, and cultural contexts shape the possibilities and limits of informal food governance. In conclusion, this paper argues that advancing urban food security in the Global South requires taking informality seriously—not as an exception to be managed, but as a constitutive element of urban life. Recognising informal green food systems as critical urban infrastructure, while confronting their embedded inequalities, is essential for navigating the contested terrain of urban sustainability transitions. Declarations Declaration of competing interest The author declares no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Declaration of Generative AI Use The author used generative AI tools to support language refinement, structural organisation, and editorial clarity during manuscript preparation. All AI-assisted outputs were carefully reviewed and substantively edited by the author. The author takes full responsibility for the originality, accuracy, and scholarly integrity of the manuscript. Acknowledgements This research was financially supported by the Program Management Unit on Area-Based Development (PMU A) [A15F640034] and by King Mongkut's Institute of Technology Ladkrabang [KREF206606]. References A. ALLEN, L. G., AND C. JOHNSON. (ed.) 2017. Environmental Justice and Urban Resilience in the Global South., New York, NY, USA.: Palgrave Macmillan. ABU HATAB, A., CAVINATO, M. E. 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Urban Forestry & Urban Greening, 87 , 128067. VAN DER JAGT, A. P. N., SMITH, M., AMBROSE-OJI, B., KONIJNENDIJK, C. C., GIANNICO, V., HAASE, D., LAFORTEZZA, R., NASTRAN, M., PINTAR, M., ŽELEZNIKAR, Š. & CVEJIĆ, R. 2019. Co-creating urban green infrastructure connecting people and nature: A guiding framework and approach. Journal of Environmental Management, 233 , 757-767. WISKERKE, J. S. C. (ed.) 2015. Urban food systems : Routledge. Additional Declarations There is NO Competing Interest. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8693626","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":581030692,"identity":"60a152bb-69db-44e5-b839-782f6f520403","order_by":0,"name":"Sakkarin Sapu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA9UlEQVRIiWNgGAWjYFACNmYgIQHlVAAxM3MDKVrOgLQwEqUFChjbwCR+LfLtx5INfu6xyGPgP/zsMe+82mj+dqCWHxXbcGoxOJN2OLHnmUQxg0SauTHvtuO5Mw4zNjD2nLmNWwtDevMBngMSiQ0SDGbSvNuO5TYAtTAztuHWIt//vPngH5AW/uPfpHnnHMudT0gLw420w8lgWxhygLY01ORuIKTF4MazZGMZoJY2iZxywznHDuRuBGo5iM8v8v1pxpJvDtQl9vMf3/bgTU1d7rzzhw8++FGBx2EwwAZGDIfBnAOE1cN1MdQRq3gUjIJRMApGEAAAWThYqYEHnMcAAAAASUVORK5CYII=","orcid":"","institution":"King Mongkut's Institute of Technology Ladkrabang","correspondingAuthor":true,"prefix":"","firstName":"Sakkarin","middleName":"","lastName":"Sapu","suffix":""}],"badges":[],"createdAt":"2026-01-25 16:00:29","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8693626/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8693626/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":101923448,"identity":"599dbf08-30e6-47a0-84af-434277c16f90","added_by":"auto","created_at":"2026-02-05 05:32:44","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":121595,"visible":true,"origin":"","legend":"\u003cp\u003eStructural problems of the conventional urban food system and the emergence of social-entrepreneurship-based informal mechanisms reconnecting upstream, midstream, and downstream food chains in Khon Kaen.\u003c/p\u003e","description":"","filename":"Picture1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8693626/v1/bccfd5dbe06080784a3df213.jpg"},{"id":101923449,"identity":"80cfa6a8-e715-4159-90bf-9835220c51e2","added_by":"auto","created_at":"2026-02-05 05:32:44","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":99685,"visible":true,"origin":"","legend":"\u003cp\u003eConceptual framework for the research design, organized around four key mechanisms—data layer, local logistics, small and informal entrepreneurship, and space—designed to connect peri-urban production with urban consumption demand.\u003c/p\u003e","description":"","filename":"Picture2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8693626/v1/8c72b14469192f70d3f36411.jpg"},{"id":101923450,"identity":"b5adf52f-4156-461c-b32b-97e037e2ab56","added_by":"auto","created_at":"2026-02-05 05:32:44","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":92366,"visible":true,"origin":"","legend":"\u003cp\u003eThe Informal Green Food Ecosystem in Khon Kaen: relational infrastructures linking green markets, community actors, and urban food access\u003c/p\u003e","description":"","filename":"Picture3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8693626/v1/3e4a30c9664e75a99f924009.jpg"},{"id":101923447,"identity":"45c475dd-9e7b-45a5-afcb-a50d6e5efb92","added_by":"auto","created_at":"2026-02-05 05:32:44","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":29201,"visible":true,"origin":"","legend":"\u003cp\u003eThe Green Optimum Economy paradigm and its urban economic linkages.\u003c/p\u003e","description":"","filename":"Picture4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8693626/v1/bcef5cc56b572b0b847a2289.jpg"},{"id":103506367,"identity":"8f4367bf-0434-48c7-a6a5-50706a572b7b","added_by":"auto","created_at":"2026-02-26 13:35:40","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1405083,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8693626/v1/a4751f57-0837-4347-86de-4ddda26443e5.pdf"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Urban Food Security and Informal Green Ecosystems in Secondary Cities:\r\nNegotiating Sustainability through the Green Optimum Economy","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eUrban food insecurity is deepening across the Global South as climate shocks, accelerated urbanisation, and economic instability combine to put increasing strain on local food provisioning systems and more starkly reveal the governance failures and structural exclusions inscribed within contemporary urban food regimens (High Level Panel of Experts (HLPE), 2020, Food and Agriculture Organization (FAO), 2019). As these pressures deepen, food security can no longer be understood solely in terms of consumer access, but must also be examined through the governance of food production systems. Regulatory standards, certification regimes, and managerial requirements impose structural costs that systematically marginalise small-scale, informal, and semi-formal producers from dominant food supply chains.\u003c/p\u003e\n\u003cp\u003eSecond-order cities (intermediate, non-capital urban centres connecting rural areas to national and global economies) are especially disadvantaged not only for lacking the institutional capacity to deal with prolonged crisis situations\u0026nbsp;(L. Riley, 2022, UN-Habitat, 2019),\u0026nbsp;but also because they exist under uneven urban development trajectories that systematically exclude informal and small-scale actors through fragmented governance along extended supply chains.\u0026nbsp;In these restricted urban spaces, food insecurity is less a question of total food supplies than one of access for many households, particularly vulnerable low-income communities that confront the challenge of obtaining affordable, safe, and nutritious foods in fragmented urban food systems\u0026nbsp;(Crush and Frayne, 2011).\u003c/p\u003e\n\u003cp\u003eIn Thailand, the expansion of supermarket chains and long-distance logistics has reshaped food provisioning over recent decades; however, fresh markets, mobile vendors, and informal community networks continue to play a vital role in everyday food access (Turner and Schoenberger, 2012, Wiskerke, 2015, Jeaheng et al., 2023). The onset of COVID-19 and associated restrictions disrupted wholesale markets, transport,\u0026nbsp;and retail operations, amplifying concerns about food safety, income loss, and affordability, particularly in urban areas with large populations of informal workers and peri-urban migrants (Laborde, 2020, Crush, 2020). Rather than constituting an exceptional crisis alone, the pandemic exposed structural vulnerabilities embedded in existing food systems, positioning cities such as Khon Kaen as salient sites for examining alternative modes of food provisioning.\u003c/p\u003e\n\u003cp\u003eMoving beyond formal planning responses, this paper examines how Khon Kaen’s food system was supported—and partially reconfigured—through a constellation of informal and semi-formal practices that together constitute an informal green ecosystem. Over a 12-month period, the research team collaborated with farmers, vendors, local entrepreneurs, municipal actors, and community groups to document, prototype, and assess mechanisms for organic vegetable production, distribution, and consumption. This approach responds to a gap in urban food security scholarship, which has often documented informality descriptively without sufficiently interrogating its governance, power relations, or long-term implications\u003c/p\u003e\n\u003cp\u003eThis analysis is grounded in the construction and application of the \u003cstrong\u003eGreen Optimum Economy (GOE)\u003c/strong\u003e as more of a critical rather than prescriptive problematic to ask how \u003cem\u003e“optima”\u003c/em\u003e across ecological, economic, and social domains are being negotiated by informality, precarity and unequal power (S. Sapu, 2022). Rather than treating ecological initiatives as marginal or additive, the framework conceptualizes them as integral to the city’s economic and social fabric, seeking an \u003cem\u003e“optimum”\u003c/em\u003e rather than a \u003cem\u003e“maximum”\u003c/em\u003e balance among ecological integrity, economic viability, and social equity. In Khon Kaen, this framework was operationalized through five interrelated objectives: (1) mapping upstream, midstream, and downstream actors, (2) prototyping organic production systems, (3) supporting green entrepreneurship, (4) organizing knowledge exchange, and (5) designing governance mechanisms for an informal green economic ecosystem.\u003c/p\u003e\n\u003cp\u003eWhile existing studies have richly documented the functions and contributions of informal food systems, much of this literature remains largely descriptive (Abu Hatab et al., 2019), offering limited engagement with the power relations, risk redistribution, and normative trade-offs that shape their operation (Crush and Frayne, 2011, J. Battersby, 2017). This paper moves beyond descriptive accounts by explicitly interrogating how informality is governed, who bears the costs of resilience, and how ecological, economic, and social “optimal” are negotiated within urban food systems (Feola, 2020, Soyinka and Siu, 2017).\u003c/p\u003e\n\u003cp\u003eThis paper explores how Khon Kaen’s food system was sustained—and, in part, reshaped—through unofficial and semi-official practices that may operate coolly as contested urban infrastructures through which compliance with or access to value and risk rather than as residual or temporary alternatives to formal planning (Lydon, 2015, J. Battersby, 2017, Soyinka and Siu, 2017). It asks: (1) How did peri-urban and urban communities in Khon Kaen build ecological production systems that contribute to city-scale food security? (2) What informal and semi-formal mechanisms—markets, logistics, data platforms, and entrepreneurship—link upstream producers to downstream consumers? and (3) How can the GOE framework help secondary cities conceptualise and govern informal green ecosystems as part of their broader urban transitions? By addressing these questions, the paper aims to speak not only to Thai urbanism but also to a wider audience concerned with the role of informal systems in urban sustainability transitions (A. Allen, 2017, Brenner., 2014).\u003c/p\u003e\n\u003cp\u003eFigure 1 illustrates how urbanisation and urban sprawl restructure food systems through uneven spatial and economic processes that disrupt upstream, midstream, and downstream segments of the value chain. On the left, spatial expansion and logistical complexity lead to rising transport costs, intermediary mark-ups, and increased exposure to shocks such as floods, droughts, and pandemics. These dynamics are not neutral; they concentrate power and value capture among large-scale actors—such as supermarkets, wholesalers, and logistics firms—while systematically displacing risks onto small and informal actors, including SMEs, street vendors, consumers, and rural producers.\u003c/p\u003e\n\u003cp\u003eThe right-hand side introduces an alternative urban mechanism centred on social entrepreneurship and urban farming as a contested mode of governance and production. By reconnecting peri-urban organic farming, contract production, food possession, and urban consumption through locally embedded logistics and informal transport networks, this model seeks to reconfigure power relations within the food system by shortening supply chains, reducing dependence on intermediaries, and creating entry points for vulnerable groups. Urban farming is thus conceptualised not merely as a productive activity, but as a multifunctional urban infrastructure through which access to food, livelihoods, and ecological value are negotiated. Rather than resolving structural inequalities, the figure highlights how informal green interventions operate within—and partially contest—uneven urban development, revealing both their transformative potential and their limits under existing political-economic conditions.\u003c/p\u003e"},{"header":"2. Conceptual and theoretical framework","content":"\u003ch2\u003e\u003cstrong\u003e2.1 Conceptual Gap and Contribution\u003c/strong\u003e\u003c/h2\u003e\n\u003cp\u003eRecent debates on urban food security in the Global South increasingly recognise the importance of informal and semi-formal food systems in sustaining access, livelihoods, and resilience under conditions of rapid urbanisation, climate disruption, and structural inequality (High Level Panel of Experts (HLPE), 2020, Food and Agriculture Organization (FAO), 2019, J. Battersby, 2017). Informal green practices—ranging from subsistence and smallholder organic farming to street vending, mobile markets, and community-based distribution—are often depicted as adaptable responses to exclusionary market conditions and fractured urban governance. Empirical investigations examine how these practices mediate poverty and marginality in relation to official systems of provision. (Crush and Frayne, 2011, Tacoli, 2017, Turner and Schoenberger, 2012). Within this body of work, the concept of the \u003cstrong\u003eInformal Green Ecosystem (IGE)\u003c/strong\u003e has emerged to capture the assemblage of actors, spaces, and practices through which food provisioning occurs beyond formal planning and regulatory frameworks. Despite its analytical value, this literature exhibits important limitations that constrain its critical and policy relevance. Yet a great deal of this literature is analytically impoverished, privileging empirical descriptions of how informal systems work while understudying the power dynamics, asymmetric regulatory capacities, and disproportionate distribution of risk that come to structure their operation over time. Informality is often venerated for its adaptability and resilience, but little is said about where value is captured, who bears the costs or risks, whether economic or ecological, and how informal actors remain structurally subordinate to dominant food regimes.\u003c/p\u003e\n\u003cp\u003eFirst, much of the \u003cstrong\u003eIGE\u003c/strong\u003e literature offers rich empirical documentation but privileges description over critical analysis (Abu Hatab et al., 2019), documenting how informal systems function while offering limited engagement with the structural conditions under which they operate\u0026nbsp;(Wiskerke, 2015, Jeaheng et al., 2023).\u0026nbsp;Informality is frequently framed as a flexible and resilient alternative, yet this emphasis often sidelines questions of power, precarity, and uneven value capture along informal food chains\u0026nbsp;(Crush, 2020).\u0026nbsp;As a consequence, informality risks being romanticised, obscuring the ways in which such systems remain embedded within broader political-economic structures dominated by large-scale retailers, intermediaries, and logistics regimes. (Brenner., 2014, A. Allen, 2017).\u003c/p\u003e\n\u003cp\u003eSecond, the concept lacks a clear normative framework for evaluating outcomes at the urban scale. Although improvements in access and short-term livelihood gains are frequently emphasised, there is limited discussion of what constitutes a socially and ecologically desirable configuration of informal systems, or how trade-offs between sustainability, equity, and economic viability should be assessed. As a result, informal food systems are often evaluated in relative or instrumental terms, rather than through explicit normative criteria linked to urban justice and ecological limits (Antle and Valdivia, 2021, Cirone et al., 2023).\u003c/p\u003e\n\u003cp\u003eIn contrast, the \u003cstrong\u003eGOE\u003c/strong\u003e framework offers a normative and strategic lens that explicitly challenges growth-oriented and efficiency-driven models of urban development (S. Sapu, 2022). By advancing the idea of an “optimum” rather than a “maximum,” it underscores the need to balance ecological limits, economic reproduction, and social justice. This framework aligns closely with critical urban theory in its rejection of technocratic solutions and its emphasis on distributive outcomes and everyday economic practices (A. Allen, 2017). However, existing applications of the GOE remain largely abstract, offering limited insight into how such an optimum is produced through everyday practices—particularly in cities characterised by fragmented governance and high levels of informality. As a result, the framework risks privileging formal policy instruments while overlooking the informal mechanisms through which urban economies actually function—particularly in cities characterised by high levels of informality. Existing applications tend to privilege formal policy instruments and planned interventions, leaving open the question of how such an optimum can be produced in contexts where governance is fragmented, and market relations are deeply uneven (UN-Habitat, 2019, Hsu and Han, 2024).\u003c/p\u003e\n\u003cp\u003eThis paper argues that the separation between these two strands of scholarship constitutes a central conceptual gap. IGE research offers rich empirical insight but lacks a normative framework for assessing structural transformation, while the GOE provides such a framework but remains disconnected from the informal practices that shape urban food systems. Without integration, informality risks being treated either as a temporary coping mechanism or as an externality to be managed, rather than as a constitutive element of urban economic life and governance (Brenner., 2014, J. Battersby, 2017).\u003c/p\u003e\n\u003cp\u003eThe central contribution of this paper lies in bridging this gap through an empirically grounded analysis of Khon Kaen. It conceptualises informal green food systems as practical infrastructures through which a GOE is enacted, rather than as marginal or transitional arrangements. Empirically, the paper demonstrates how peri-urban organic farming, green markets, mobile logistics, and small-scale green entrepreneurship reconfigure upstream–midstream–downstream relations by shortening supply chains, redistributing value, and expanding access for vulnerable groups (Crush, 2020, Laborde, 2020). Analytically, it foregrounds informality as a contested terrain shaped by power relations, risk redistribution, and negotiated optimisation rather than as an inherently progressive alternative.\u003c/p\u003e\n\u003cp\u003eBy integrating the IGE with the GOE, this paper advances three contributions. First, it repositions informality as a constitutive terrain of urban governance and sustainability, rather than a residual or exceptional condition. Second, it operationalises the GOE through empirically grounded practices, showing how ecological integrity and social equity are negotiated in everyday urban contexts and intensified during moments of crisis. Third, it develops a transferable analytical framework for interpreting food-system transitions in secondary cities, where hybrid arrangements between formal institutions and informal actors are not anomalies but the prevailing mode of urban development (Tacoli, 2017, UN-Habitat, 2019).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2 The Green Optimum Economy framework\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe notion of a GOE was developed through an earlier strand of work on ecological urban futures in Khon Kaen (S. Sapu, 2022). It can be summarised as a triple bottom framework comprising: (1)\u0026nbsp;Ecological optimum: enhancing ecological functions through organic agriculture, soil regeneration, biodiversity, water management, and reduced chemical use; (2) Economic optimum: ensuring the economic viability of green practices by supporting local entrepreneurship, green markets, value-added processing, and fair prices for producers; and (3) Social optimum: promoting social inclusion, equity, and well-being by integrating vulnerable groups, ensuring access to safe food, creating learning spaces, and nurturing community solidarity.\u003c/p\u003e\n\u003cp\u003eUnlike mainstream \u003cem\u003e“green growth”\u003c/em\u003e rhetoric, the GOE explicitly acknowledges ecological limits and socio-economic ceilings (Feola, 2020). It does not treat sustainability as a function of scale or efficiency, but rather as an outcome negotiated through competing demands, limitations, and power relations. In this paper, we integrate the GOE with an IGE Model (Luo and Patuano, 2023) developed from empirical work in Khon Kaen. Together, these concepts offer a systemic lens for understanding how food, ecology, economy, and social justice intersect in a secondary city. But the current articulations of GOE have, for the most part, remained conceptual, leaving too many questions unanswered about how this optimum is achieved in practice, especially in cities that are highly informalised, with governance often fragmented and markets marked by unevenness.\u003c/p\u003e\n\u003cp\u003eThe work of Alexander van der Jagt (2023, 2019) has been influential in reframing urban greening as a socially embedded, co-produced process, challenging technocratic, top-down approaches to green infrastructure. This literature emphasises informal practices, civic stewardship, and everyday governance as central to urban ecological transitions, rather than treating green space as a purely planned or managerial outcome. While analytically productive, this focus has largely remained within the domain of green spaces and stewardship. Building on this perspective, the present study extends the analysis to urban food systems, where green practices are directly intertwined with livelihoods, value chains, and access to basic needs. The Khon Kaen case illustrates that informal green food systems—such as peri-urban organic farming, green markets, and mobile vendors—function as everyday governance infrastructures that both facilitate resilience and reveal underlying power relations and uneven risk distribution. In doing so, the paper advances van der Jagt’s framework by foregrounding how informality functions not only as a mode of co-production, but also as a contested terrain through which urban sustainability and food system transitions are negotiated under conditions of structural inequality.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.3 Integrating Green Optimum Economy and Informal Green Ecosystem Model\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis paper presents an integrated conceptual framework that combines the \u003cstrong\u003eGOE\u0026nbsp;\u003c/strong\u003eand the \u003cstrong\u003eIGE Model\u003c/strong\u003e (Ta et al., 2025), treating them as mutually constitutive rather than separate analytical lenses. The GOE provides the normative and strategic grounding, challenging growth-maximising logics by foregrounding an optimal balance among ecological limits, economic viability, and social equity. It establishes a macro-level rationale for evaluating urban food systems not solely in terms of scale or efficiency, but in relation to sustainability thresholds and distributive justice.\u003c/p\u003e\n\u003cp\u003eBuilding on this foundation, the IGE Model operationalizes the GOE at the urban scale by revealing how optimality is negotiated and enacted through everyday practices within informal and semi-formal green food networks. These networks—comprising smallholder producers, street vendors, community markets, and urban consumers (Choi et al., 2020, Martin, 2014) —function as adaptive socio-ecological infrastructures that shorten supply chains, reduce transaction costs, and redistribute access to green food beyond middle-class consumption niches. In this sense, informality becomes a \u003cem\u003emechanism of optimization\u003c/em\u003e, translating abstract sustainability principles into context-sensitive, place-based arrangements.\u003c/p\u003e\n\u003cp\u003eThe integrated framework conceptualizes urban food systems as \u003cstrong\u003edynamic optimization processes\u003c/strong\u003e, in which ecological limits, economic constraints, and social needs are continuously balanced through spatial practices and informal governance. Rather than treating informality as a deviation from formal planning ideals, the framework reframes it as a productive interface where Green Optimum principles are tested, adjusted, and materialized on the ground. This synthesis thus bridges macro-level economic reasoning with meso- and micro-level urban food dynamics, offering a scalable yet grounded model for understanding and guiding sustainable, inclusive urban food transitions in cities of the Global South.\u003c/p\u003e"},{"header":"3. Methodology","content":"\u003cp\u003e\u003cstrong\u003e3.1 Research design and epistemological approach\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study adopted a mixed-methods, action-oriented research design grounded in a critical–interpretive epistemology. Rather than treating urban food systems as neutral technical arrangements, the research approached them as socio-spatial assemblages shaped by power relations, governance structures, and everyday practices. Knowledge was therefore produced not only through observation and measurement, but also through engagement, experimentation, and reflexive learning with actors embedded in informal and semi-formal food systems.\u003c/p\u003e\n\u003cp\u003eMethodologically, the research combined value-chain analysis, participatory action research (PAR), Urban Lab prototyping, and tactical urbanism experiments. Value-chain analysis was used to map upstream–midstream–downstream relations and identify structural bottlenecks and asymmetries. PAR and the Urban Lab approach enabled co-production of situated knowledge with farmers, vendors, entrepreneurs, and municipal actors, while tactical urbanism functioned as an experimental method to test low-cost, temporary interventions—such as pop-up markets, community gardens, and pilot logistics routes—and to observe their socio-economic and spatial effects in real-world conditions.\u003c/p\u003e\n\u003cp\u003eThe project was conducted over a 12-month period and structured around five objectives: mapping and linking value-chain actors, prototyping organic production systems, supporting green entrepreneurship, facilitating knowledge exchange, and developing a management mechanism for an informal green food ecosystem.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.2 Study area and data collection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study was conducted in Khon Kaen and its surrounding peri-urban districts in Northeastern Thailand. As a secondary city, Khon Kaen occupies an intermediary position between rural production zones and urban markets, while exhibiting high levels of informality in food provisioning and employment. Upstream sites included peri-urban organic farming communities in Nam Phong and Sam Sung districts (approximately 30 km from the city), while midstream and downstream activities focused on the Khon Kaen Green Market, mobile vegetable trucks, local organic restaurants, school canteens, and low-income urban communities.\u003c/p\u003e\n\u003cp\u003eData collection combined qualitative and quantitative methods: value-chain mapping of producers, vendors, logistics routes, and institutional consumers; semi-structured interviews with farmers, hawkers, market managers, municipal officials, restaurant owners, school administrators, and representatives of vulnerable groups; consumer surveys at green markets and community gardens; participant observation during Urban Lab events and tactical interventions; and document analysis of relevant policy documents, municipal strategies, NGO reports, and the project’s final research report.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.3. Data collection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData were collected through:\u003c/p\u003e\n\u003cp\u003e• Value-chain mapping of farmers, vendors, distribution routes, restaurants, and institutional consumers;\u003c/p\u003e\n\u003cp\u003e• Semi-structured interviews with organic farmers, hawkers, market managers, municipal officials, school administrators, restaurant owners, and representatives of vulnerable groups;\u003c/p\u003e\n\u003cp\u003e• Surveys of consumers at green markets and community gardens regarding their preferences, willingness to pay, and perceptions of food safety;\u003c/p\u003e\n\u003cp\u003e• Participant observation during Urban Lab events, training workshops, and tactical interventions such as community garden set-ups, pop-up markets, and mobile truck routes;\u003c/p\u003e\n\u003cp\u003e• Document analysis of relevant policy documents, municipal strategies, NGO reports, and the final research report itself.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.4. Data analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eQualitative data were analysed thematically, with codes related to informality, governance, resilience, entrepreneurship, logistics, and social inclusion (J. Battersby, 2017, Soyinka and Siu, 2017). Quantitative data from surveys and production records were analysed descriptively to quantify changes in supply volumes, income levels, and access patterns. Findings were synthesised into an IGE Model that captures the key components and relationships uncovered in the field. This model, in turn, was interpreted through the GOE framework to derive conceptual insights and policy implications (S. Sapu, 2022, Feola, 2020).\u003c/p\u003e"},{"header":"4. Context: Khon Kaen’s food system and green initiatives.","content":"\u003cp\u003eKhon Kaen is a regional economic hub in Northeastern Thailand. The city has experienced rapid growth through education, logistics, healthcare,\u0026nbsp;and services, while remaining closely connected to an agricultural hinterland where rice, vegetables, and livestock are produced. Organic agriculture has gained momentum in Khon Kaen city over the past decade, driven by health concerns, niche market opportunities, and the spread of participatory guarantee systems (PGS)(IFOAM, 2016, Mougeot, 2005). The Khon Kaen Green Market has become a focal point for organic and safe food, providing a weekly platform where certified farmers, safe-vegetable producers, and food processors sell directly to consumers under the oversight of municipal and public health authorities. The municipality supported the green market by allocating part of a public park for Friday evening trading and permitting the renovation of a vacant building into a daily green grocery shop.\u003c/p\u003e\n\u003cp\u003eThe onset of COVID-19 introduced principal stresses. Lockdowns and restrictions limited movement, reduced restaurant demand, and disrupted wholesale channels. Yet the crisis also created openings for innovation. The Khon Kaen City Development Company and local actors launched mobile “pum-puang” trucks that brought fresh food into neighbourhoods, while community groups established or revived vacant lands, small gardens, and sharing farms to support those who lost income, including informal workers and unhoused individuals.\u003c/p\u003e\n\u003cp\u003eFormal market mechanisms predominantly organize production and distribution through capital-intensive supply chains, where commodity flows are structured around large-scale investments and centralized market logics. By contrast, the Informal Green Economy reconnects small-scale urban resource bases and localized cost structures, linking vulnerable populations as both producers and consumers through shorter, socially embedded circuits of exchange. This mode of economic organization challenges dominant market hierarchies by foregrounding accessibility, inclusivity, and ecological sustainability, thereby offering an alternative pathway for urban development that aligns with concerns of social equity and environmental stewardship. These overlapping initiatives formed the practical foundation upon which the project built, using research funding and design methods to connect disparate efforts into a more coherent city-wide ecosystem (L. Riley, 2022).\u0026nbsp;\u003c/p\u003e"},{"header":"5. Findings ","content":"\u003cp\u003e\u003cstrong\u003e5.1 Reconfiguring the Urban Food Value Chain through Informal Green Practices\u0026nbsp;(Upstream: peri-urban organic production)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study identified significant structural inefficiencies in the food distribution system. Vegetables consumed in Khon Kaen were frequently transported to Bangkok\u0026mdash;covering a round-trip distance of more than 950 kilometres\u0026mdash;before being redistributed back to the city. This circuitous logistics pattern substantially increased transportation costs, reduced returns for upstream farmers, and enabled intermediaries to capture a disproportionate share of value. At the same time, the findings revealed strong and growing consumer demand for organic vegetables that consistently exceeded local production capacity. This persistent supply\u0026ndash;demand gap indicates a \u0026ldquo;blue ocean\u0026rdquo; market with considerable potential for future expansion.\u003c/p\u003e\n\u003cp\u003eEmpirical evidence suggests that food insecurity in Khon Kaen is more closely shaped by weak coordination across the urban food value chain than by insufficient production. Interviews with peri-urban organic farmers (comprising 86 stalls), including 33 certified organic producers, 23 safe-agriculture producers, and 30 processed-food vendors,\u0026nbsp;revealed that, prior to the intervention, most producers sold their products through intermediaries or distant wholesale markets, often receiving payment 30\u0026ndash;45 days after delivery. This delayed cash flow constrained reinvestment and increased production risk, particularly for small-scale households cultivating fewer than 5\u0026ndash;7 plots. Meantime, consumer surveys conducted at green markets showed sustained unmet demand for organic vegetables, especially among urban households concerned with health and food safety.\u003c/p\u003e\n\u003cp\u003eThe emergence of informal and semi-formal green practices altered these dynamics by creating direct and semi-direct linkages between producers and urban consumers. Peri-urban farms supplying the green market and mobile distribution routes typically operate within a 30-kilometre radius, with average transport times of approximately 30\u0026ndash;35 minutes. This spatial proximity reduced logistics costs and enabled same-day or next-day transactions, improving income predictability for producers while stabilising prices for consumers.\u003c/p\u003e\n\u003cp\u003eTable 1\u0026nbsp;outlines the characteristics of the 18\u0026nbsp;producers and vendors supplying the Khon Kaen Green Market. The system is dominated by peri-urban actors, with most producers located outside the urban core, yet transport distances remain relatively short, averaging 26.9\u0026nbsp;km with a mean travel time of approximately 32\u0026nbsp;minutes. The majority of participants operate under organic standards, while others follow safe food or GAP practices. Farm sizes are generally small, ranging from home gardens to plots of up to 6\u0026nbsp;rai (9,600\u0026nbsp;square meters), with a few larger community-managed sites. Organisationally, the market comprises individual households and community enterprises, with actors occupying multiple positions along the value chain as producers, producer\u0026ndash;vendors, and informal traders, reflecting the green market ecosystem\u0026apos;s flexible, hybrid structure.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e1:\u003c/strong\u003e Characteristics of Khon Kaen Green Market Members\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eCategory\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eKey Characteristics\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eNumber of members\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e18 producers/vendors\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eSpatial location\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4 urban (\u0026le;2 km); 14 peri-urban/rural\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eAverage distance\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e26.9 km (median 28.4 km)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eTransport time\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eAvg. ~32 minutes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eProduction standards\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e12 organic; 6 safe food / GAP\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eFarm scale\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eSmall plots (home gardens to 6 rai or 9,600 Square Metter); few large community plots\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eOrganisation\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eIndividual households and community enterprises\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eRole in value chain\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eDirect producers, mixed producers\u0026ndash;vendors, informal traders\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eSource: author (2022)\u003c/p\u003e\n\u003cp\u003eFrom a grounded perspective, these practices did not eliminate intermediaries altogether but selectively reconfigured their role. Market managers, mobile vendors, and small processors acted as relational brokers rather than price-setting middlemen. This shift redistributed value along the chain, allowing informal actors to capture economic benefits that were previously absorbed by upstream actors. Conceptually, these findings support the interpretation of informal food systems as adaptive infrastructures that reorganize value-chain relations under conditions of market exclusion, aligning with the GOE\u0026rsquo;s emphasis on optimization rather than maximization.\u003c/p\u003e\n\u003cp\u003eInterviews with organic farmers reveal that\u0026nbsp;\u003cem\u003e\u0026ldquo;\u003c/em\u003e\u003cem\u003eproduction expansion is constrained mainly by climatic variability and recurrent hazards such as floods and drought. Limited capital prevents farmers from absorbing these risks, rendering scale-up economically precarious.\u003c/em\u003e \u003cem\u003eDesigning and planning agricultural practices that are calibrated to farmers\u0026rsquo; livelihood costs and economic capacities may therefore offer a more viable pathway, aligning organic production with their everyday socio-economic realities.\u003c/em\u003e\u003cem\u003e\u0026rdquo;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe project identified and engaged a network of organic and \u003cem\u003e\u0026ldquo;safe\u0026rdquo;\u003c/em\u003e vegetable producers in the peri-urban zones around Khon Kaen. Many of these farms were family-run, combining small plots of land with labour from household members. Some were long-term organic producers, while others were conventional farmers who experimented with organic methods on part of their land. Interview findings reveal that \u003cem\u003e\u0026ldquo;organic\u0026rdquo;\u003c/em\u003e is understood by producers not merely as the absence of chemical inputs, but as a holistic livelihood practice encompassing improved health, reduced economic risk, and strengthened social relations. Organic farming is thus framed as a relational and socio-economic strategy that integrates well-being, livelihood security, and mutual support, rather than solely a technical mode of agricultural production. It can be understood as a mode of production that aligns with the organic integrity of the household itself\u0026mdash;reflecting producers\u0026rsquo; aspirations for health, livelihood security, and social coherence, rather than merely compliance with technical standards.\u003c/p\u003e\n\u003cp\u003eVacant or under-utilised land, including low-lying areas, roadside verges and abandoned plots, was transformed into productive agricultural spaces. Through training and demonstration, farmers improved soil quality, reduced chemical inputs, and experimented with crop diversification, including leafy greens, herbs, mushrooms, and indigenous vegetables (Tacoli,\u0026nbsp;2017, Mougeot,\u0026nbsp;2005).\u0026nbsp;Two empirically grounded case studies are particularly illustrative of the adaptive reuse of vacant urban land in Khon Kaen: (1)\u0026nbsp;the transformation of residual inner-city space beneath the elevated railway into sites for vegetable cultivation, and (2)\u0026nbsp;the repurposing of an abandoned suburban school campus as a source of pesticide-free food supplying the city.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e5.2 Midstream Mechanisms: Green Markets and Informal Logistics as Governance Devices\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e5.2.1 The Green Market as a Hybrid Governance Space\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eField observations and interviews indicate that the Khon Kaen Green Market functioned as a central coordination node, linking approximately 80\u0026ndash;90 vendors, including certified organic producers, safe vegetable growers, food processors, and prepared food sellers. Market access was governed through a hybrid arrangement combining participatory farm inspections, municipal food-safety testing, and peer-based accountability, rather than relying solely on formal certification. While these mechanisms lowered entry barriers for small-scale and informal producers, they also shifted responsibility for food safety and quality assurance onto producers and community networks. In organic food systems, trust is therefore an institutional outcome shaped by local governance rather than an inherent market attribute. Trust-based inspection systems, when supported by municipal recognition, can reduce certification costs and expand access to safe food, but they also raise questions about how regulatory labour and risk are unevenly distributed within hybrid food governance regimes.\u003c/p\u003e\n\u003cp\u003eConsumer interviews (146 samplings) further revealed that repeated face-to-face interactions played a critical role in shaping trust. Many consumers reported learning about cultivation methods, seasonal variability, and price fluctuations directly from farmers, which in turn influenced their purchasing decisions over time. This relational process stabilised demand, particularly for small producers who lacked branding or formal certification. As one market manager noted during participant observation, \u003cem\u003e\u0026ldquo;trust accumulates through presence rather than labels.\u0026rdquo;\u003c/em\u003e Consumers\u0026rsquo; decisions to purchase organic products were shaped by negotiated trade-offs between certification standards and price affordability. While doubts persisted about the rigour and consistency of inspection mechanisms, the involvement of local authorities in market governance helped legitimise\u0026nbsp;these arrangements. Rather than resolving regulatory gaps, these locally embedded governance structures produced forms of contingent trust that enabled consumers to accept informal standards as credible substitutes for formal certification, thereby mediating tensions among affordability, safety, and institutional oversight.\u003c/p\u003e\n\u003cp\u003eAnalytically, the green market functioned as a hybrid governance space, where informal rules and formal oversight intersected. Governance emerged through negotiated practices rather than fixed regulations, illustrating how informal institutions can compensate for gaps in formal food governance while remaining embedded within municipal frameworks. It can therefore be argued that local municipalities play a pivotal role in shaping locally embedded mechanisms and standards that intervene in dominant organic food market logics in everyday urban life. Through such interventions, municipal actors do not merely facilitate market functioning but actively reconfigure governance arrangements to safeguard urban residents\u0026rsquo; access to safe food, particularly in contexts where formal certification systems remain inaccessible or exclusionary.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e5.2.2 Informal Green Logistics and Mobile Distribution\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe project introduced and strengthened innovations in green logistics, under the label \u0026ldquo;GREEN DEE = GOOD GREEN\u0026rdquo;. Mobile distribution systems\u0026mdash;particularly organic trucks and \u0026ldquo;pum-puang\u0026rdquo; vendors\u0026mdash;extended the reach of the green ecosystem beyond fixed market sites. Mapping of distribution routes showed that these trucks connected peri-urban farms, green markets, residential neighbourhoods, offices, and school canteens along flexible, demand-responsive circuits. Pilot data indicated that unsold produce from weekly Green\u0026nbsp;Markets could be redistributed through mobile routes, generating additional margins of approximately 20\u0026ndash;25 percent while reducing food waste.\u003c/p\u003e\n\u003cp\u003eIn the initial phase of the study, an Urban Lab approach was used as an experimental platform for iterative trial-and-error. These early experiments generated empirical insights into demand patterns, constraints, and stakeholder needs, which were subsequently used as key inputs and materials for a series of participatory workshops. Then, Co-design workshops with farmers, vendors, and researchers revealed that product formats were strategically differentiated according to urban contexts. Fresh produce was prioritised for households, restaurants, and school canteens; ready-to-cook packages targeted office districts with family households; and prepared foods served single-person households and lunchtime consumers. These distinctions were not imposed top-down but emerged through iterative experimentation and feedback from vendors and consumers.\u003c/p\u003e\n\u003cp\u003eThese findings foreground logistics as a socially negotiated practice rather than a purely technical function. Informal logistics redistributed not only food but also risk, information, and value across the chain, reinforcing the GOE\u0026rsquo;s emphasis on balancing ecological sustainability, economic viability, and social inclusion. A two-month pilot of the Green Dee service across diverse urban settings\u0026mdash;including low-income communities, hospitals, government offices, public parks, and schools\u0026mdash;highlighted the distributive role of informal logistics in addressing food access inequalities. The service was particularly significant for elderly adults with limited mobility, whose everyday access to fresh,\u0026nbsp;safe food is constrained by inadequate public transport systems in secondary cities. By bringing organic and safe produce directly to households, the mobile pum-puang truck effectively bypassed spatial and infrastructural barriers embedded in the formal food system. These findings suggest that mobile vendors operate not merely as market actors, but as forms of informal urban infrastructure that actively redistribute access to food, mitigate mobility-based exclusion, and contribute to food justice by extending the reach of green food systems to populations otherwise marginalised in urban planning and retail geographies.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e5.2.3 Green Start-up Incubator: Entrepreneurialisation and the Neoliberalisation of Sustainability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo advance the economic dimension of the Green Optimum Economy (GOE), the project established a green start-up incubator to support small-scale actors across the organic food chain, including young farmers, micro-processors, informal vendors, and community-based restaurants. Evidence from the Green Hackathon 2022, as documented in the project report, suggests that the incubator operated more as a space for exchange and experimentation than as a conventional business accelerator. Rather than fast-tracking start-ups, it enabled interaction among farmers, traders, processors, technology developers, and public agencies, allowing participants to test ideas and build networks.\u003c/p\u003e\n\u003cp\u003eOf the 32 start-ups involved, 20 (62.5% of the total) operated primarily at the upstream production level, while 8 and 4 were concentrated in midstream and downstream activities, respectively. Interviews indicate that most upstream entrepreneurs worked on land inherited from their parents, but were actively experimenting with new technologies and management practices to improve productivity, resilience, and responsiveness to market demand. Among midstream and downstream actors, five also controlled land-based production assets, allowing them to combine processing, distribution, or retail activities with farming. This overlap points to an emerging form of vertically integrated green entrepreneurship, shaped less by start-up capital alone than by access to land, intergenerational assets, and the capacity to adapt innovation to local conditions.\u003c/p\u003e\n\u003cp\u003eTraining activities\u0026mdash;including organic production, branding, digital marketing, and basic business planning\u0026mdash;enabled participants to experiment with new product formats such as ready-to-cook vegetable kits and small-scale processed foods. Yet the outcomes were uneven. Only a small number of participants were able to sustain their ventures beyond the pilot phase, with many constrained by limited access to capital, labour shortages, and fluctuating market demand. Under these conditions, green entrepreneurship functioned primarily as a livelihood strategy rather than a pathway to scalable or stable growth.\u003c/p\u003e\n\u003cp\u003eFrom a critical perspective, the incubator reflects wider processes of the neoliberalisation of sustainability, in which responsibility for ecological transition is devolved to individual entrepreneurs and communities. Rather than addressing structural constraints within food systems, such initiatives often require informal actors to absorb market risks, certification costs, and demand uncertainty. The findings suggest that green start-ups contribute meaningfully to food system transitions only when embedded within supportive configurations of markets, logistics, and public institutions; in their absence, entrepreneurial pathways risk reproducing precarity rather than advancing a durable economic optimum.\u003c/p\u003e\n\u003cp\u003eIn secondary cities, policies that support green entrepreneurial incubation can play a strategic role in strengthening urban food systems. Many cities in the Global South face a \u003cem\u003e\u0026ldquo;missing middle\u0026rdquo;\u003c/em\u003e demographic pattern, as working-age populations migrate to metropolitan centres, weakening local food economies and accelerating population ageing. Supporting locally embedded green and food-related enterprises can encourage younger generations to remain in or return to their hometowns, thereby stabilising livelihoods, reinforcing food value chains, and enhancing the long-term resilience and inclusiveness of urban food systems.\u003c/p\u003e\n\u003cp\u003eInterviews with young entrepreneurs who returned to their hometowns or secondary cities point to a set of overlapping, often pragmatic motivations rather than straightforward opportunity-seeking. For some, relocation followed parental illness or death, creating pressure to take over family land or businesses in the absence of successors. Others described returning after financial setbacks linked to failed investments or unstable employment in large metropolitan areas. Concerns about physical and mental health associated with urban living also featured prominently in these decisions. Taken together, these accounts indicate that return migration is frequently necessity-driven and shaped by broader conditions of labour precarity, family obligation, and uneven urban development. In this context, public policy should move beyond metropolitan-centric innovation strategies and place greater emphasis on supporting start-up incubation and small-scale entrepreneurship in secondary cities, as a means of creating viable livelihoods, redistributing investment, and expanding employment opportunities outside major urban centres.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e5.3 Downstream Dynamics: Consumption, Trust, and Value Construction\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDownstream actors were not passive recipients but actively shaped the IGE. Survey data and interviews show that consumers prioritized affordability and trust alongside, and sometimes over, formal organic certification. Many were willing to purchase produce described as \u003cem\u003e\u0026ldquo;safe\u0026rdquo;\u003c/em\u003e or \u003cem\u003e\u0026ldquo;organic-in-practice\u0026rdquo;\u003c/em\u003e when relational trust with producers had been established through repeated interaction and local verification mechanisms. This form of trust-based valuation was particularly important for low- and middle-income households, for whom certified organic products sold through supermarkets remained economically inaccessible.\u003c/p\u003e\n\u003cp\u003eSmall restaurants sourcing green materials and mobile vendors reported increased flexibility and differentiation, enabling them to adjust menus according to seasonal availability while reducing dependence on volatile wholesale supply chains. These practices reinforced local circulation of value and strengthened producer\u0026ndash;consumer relations beyond one-off transactions.\u003c/p\u003e\n\u003cp\u003eHowever, interviews with midstream restaurant owners reveal a key limitation of the IGM: demand consistently exceeds supply. While the GOE prioritises sufficiency and balance over volume expansion, this orientation constrains the system\u0026rsquo;s ability to respond to sustained market demand. As a result, restaurants\u0026mdash;particularly those with high vegetable consumption\u0026mdash;face supply instability despite strong consumer interest.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFrom a policy perspective, this tension underscores the need for targeted state support to expand the upstream base of small-scale producers and strengthen collective aggregation mechanisms to\u0026nbsp;secure minimum production volumes. In secondary cities across Northeastern Thailand, where local restaurants form a dense and culturally embedded food economy with high vegetable consumption, such interventions are critical to aligning the principles of optimisation with the material requirements of urban food provisioning.\u003c/p\u003e\n\u003cp\u003eGrounded in everyday interactions, these dynamics reveal that value in informal food systems is socially constructed and continuously negotiated. Access, affordability, and food safety emerged not solely from price mechanisms or regulation, but from relational infrastructures that link production and consumption. This underscores the limits of market-centric approaches to urban food security and highlights the importance of informal systems in mediating sustainable and equitable food provisioning.\u003c/p\u003e\n\u003cp\u003eFigure 3 illustrates the IGE in Khon Kaen as a relational urban infrastructure operating across social, virtual, and physical spaces. Rather than a linear supply chain, the diagram depicts dense interconnections through which food, information, trust, and social support circulate among peri-urban producers, markets, intermediaries, and consumers. The Khon Kaen Green Market emerges as a central coordinating hub, linking upstream production with downstream consumption while facilitating feedback, learning, and redistribution.\u003c/p\u003e\n\u003cp\u003eActors such as community organisations, food banks, and local enterprises bridge physical food spaces\u0026mdash;markets, restaurants, school canteens, and learning venues\u0026mdash;with social mechanisms that support vulnerable groups and urban poor communities. The overlapping flows highlight how informal systems enhance access and adaptability, particularly during disruptions, while simultaneously revealing the uneven distribution of risk borne by informal actors. The figure thus reinforces the finding that food security in Khon Kaen is produced through negotiated, hybrid arrangements rather than formal planning alone.\u003c/p\u003e"},{"header":"6. Discussion: Informality, Power, and Urban Food Transitions","content":"\u003cp\u003eThis paper examined how informal and semi-formal green food systems contribute to urban food security in a secondary city context, and how these practices can be interpreted through the GOE framework. Drawing on empirical evidence from interviews, value-chain mapping, pilot interventions, and consumer surveys conducted in Khon Kaen, the findings demonstrate that informal green food ecosystems can enhance food access, stabilise livelihoods, and reconfigure value chains in ways that formal market systems often fail to achieve. At the same time, the evidence also reveals that informality is not an unambiguous solution, but a contested terrain shaped by power relations, uneven risk distribution, and institutional constraints.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e6.1 Informal Green Ecosystems: Infrastructure and Precarity\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe results demonstrate that informal food systems in Khon Kaen function as critical urban infrastructure, mediating food access, trust, and coordination across upstream, midstream, and downstream actors. Green markets, mobile vendors, and peri-urban farms collectively filled gaps in formal food provisioning, particularly during disruptions such as the COVID-19 pandemic. These systems enabled small producers and informal vendors to capture greater value, while improving affordability and accessibility for urban consumers.\u003c/p\u003e\n\u003cp\u003eHowever, these benefits coexist with forms of precarity that are often underplayed in celebratory accounts of informality. Informal actors continue to bear disproportionate risks related to income instability, labour conditions, regulatory uncertainty, and dependence on relational trust rather than enforceable rights. Resilience, in this sense, is frequently achieved through households and individuals absorbing risk rather than through structural protections. Recognising informality as infrastructure, therefore, requires acknowledging its dual character: as a source of flexibility and innovation, but also as a site where vulnerability is reproduced.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e6.2 The Green Optimum Economy as a Negotiated Process\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Green Optimum Economy framework offers a valuable lens for interpreting these dynamics by shifting attention away from growth maximization toward balanced outcomes across ecological, economic, and social dimensions. In Khon Kaen, optimisation did not emerge as a stable or predefined condition, but as a negotiated process shaped by everyday practices, trade-offs, and compromises. Ecological goals—such as organic cultivation and reduced chemical use—were continually balanced against the needs of livelihoods, market demand, and logistical constraints.\u003c/p\u003e\n\u003cp\u003eImportantly, what counted as \u003cem\u003e“optimum”\u003c/em\u003e varied across actors and contexts. For small farmers, optimisation often meant income predictability rather than maximisation; for vendors, it involved flexibility and reduced waste; for consumers, affordability and trust frequently outweighed formal certification. These findings suggest that the Green Optimum Economy should be understood not as a blueprint or policy endpoint, but as a heuristic device that exposes tensions between competing priorities and makes visible the politics of sustainability transitions.\u003c/p\u003e\n\u003cp\u003eHowever, the key difference of\u0026nbsp;the Green Optimum Economy lies in analytical scale and orientation. While Górska-Warsewicz’s work (2021) primarily examines structural constraints and systemic challenges within existing institutional and market frameworks—such as regulation, certification, and supply-chain stability—the Green Optimum Economy reframes these dynamics as part of a multidimensional transition pathway. It places stronger emphasis on bottom-up experimentation, spatial interventions, and the integration of informal and semi-formal practices into urban food systems. Moreover, the social dimension is more explicitly foregrounded in the Green Optimum Economy, which conceptualizes food systems as social infrastructures that integrate vulnerable groups, foster collective learning, and strengthen networks capable of responding to crises. Together, these differences position the Green Optimum Economy not as a competing explanation, but as a complementary framework that translates structural insights from the literature into an operational, place-based model for sustainable urban food transitions.\u003c/p\u003e\n\u003cp\u003eThese optimums are not automatically aligned. For example, organic production can raise prices, potentially excluding low-income consumers; or entrepreneurship might increase competition for small vendors. The Green Optimum Economy framework helps identify such tensions and asks how ecological, economic, and social goals can be balanced in a way that is locally acceptable and sustainable.\u003c/p\u003e\n\u003cp\u003eFigure 4\u0026nbsp;conceptualises the Green Optimum Economy as an integrative paradigm that positions the household economy at the core of urban economic transformation, mediating between neighbourhood and local economies through sharing, circular, and creative economic practices. At the upper level, the household economy serves as a connective node, translating everyday practices into broader local economic circuits and enabling value creation embedded in place-based social relations.\u003c/p\u003e\n\u003cp\u003eAt the urban scale, the Green Optimum Economy provides a framework for advancing a green and inclusive city by aligning local economic activities with ecological and social objectives. This is operationalised through the integration of green infrastructure and nature-based solutions, which form the material and ecological foundations of urban sustainability. The paradigm emphasises locally appropriate and trust-based value chains, content-driven green products, and context-sensitive logistics tailored to specific consumer groups. Together, these elements support both passive and active income generation while reinforcing local trust, resilience, and inclusivity. By linking household practices to green infrastructure and nature-based solutions, the Green Optimum Economy paradigm articulates a transition pathway in which economic viability, ecological integrity, and social equity are pursued as mutually reinforcing rather than competing goals.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e6.3 Hybrid Governance and Uneven Power Relations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Khon Kaen case highlights the emergence of hybrid governance arrangements in which municipal authorities, civil society organisations, market committees, and informal actors jointly shape food provisioning. Municipal support—through permissions, access to public land, food safety testing, and recognition of green markets—played an enabling role without fully formalising informal systems. This hybrid approach created institutional space for experimentation and inclusion.\u003c/p\u003e\n\u003cp\u003eYet hybrid governance is not inherently equitable. Decisions about market access, standards, and participation remain unevenly distributed, and informal actors often lack bargaining power when rules change or support is withdrawn. Inclusion within governance arrangements may therefore be conditional and reversible, reinforcing dependence rather than autonomy. A critical reading of hybrid governance thus cautions against treating collaboration as inherently progressive, and calls for closer attention to how authority, responsibility, and risk are allocated\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e6.4 Crisis as Stress Test: Lessons from COVID-19\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe COVID-19 pandemic served as a stress test, revealing both the strengths and limitations of informal green food systems. While informal networks proved more adaptable than formal supply chains in the short term, their capacity to scale and sustain support under prolonged crisis remains uncertain. In many cases, continuity depended on intensified labour, unpaid care work, and informal reciprocity, raising questions about who ultimately bears the costs of resilience.\u003c/p\u003e\n\u003cp\u003eThis observation challenges narratives that position informality as a permanent solution to systemic food insecurity. Instead, the findings suggest that informal systems are most effective when recognised and supported as part of a broader food governance landscape, rather than as substitutes for structural reform.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e6.5 Implications for Urban Food Transitions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTaken together, the findings indicate that informal green food ecosystems can play a significant role in advancing more just and sustainable urban food systems, particularly in secondary cities characterised by limited planning capacity and high informality. However, their contribution depends on how they are governed, supported, and integrated. Treating informality as a central component of urban infrastructure necessitates policies that mitigate precarity, safeguard livelihoods, and ensure that the benefits of green transitions are not achieved at the expense of vulnerable groups.\u003c/p\u003e\n\u003cp\u003eBy integrating the Informal Green Ecosystem perspective with the Green Optimum Economy framework, this paper presents a critically grounded approach to understanding urban food transitions—one that foregrounds negotiation, power, and everyday practices rather than idealized models of sustainability.\u003c/p\u003e"},{"header":"7. Conclusion","content":"\u003cp\u003eThis paper examines how informal and semi-formal green food systems function as critical components of urban food security in a secondary city of the Global South. Using Khon Kaen as an empirical case, the study demonstrates that food insecurity is shaped less by absolute scarcity than by the organisation, governance, and accessibility of urban food systems. Informal green practices—including peri-urban organic farming, green markets, mobile distribution, and small-scale green entrepreneurship—were shown to play a significant role in reconfiguring upstream–midstream–downstream relations, particularly under conditions of disruption.\u003c/p\u003e\n\u003cp\u003eThe findings contribute to urban food scholarship by conceptualising informal green food systems not as residual or transitional arrangements, but as relational infrastructures through which food access, value, and governance are produced in practice. At the same time, the analysis cautions against romanticising informality. While informal systems enhance flexibility and responsiveness, they also reproduce precarity by redistributing risk onto households and informal workers. Resilience, in this sense, is not cost-free, but often achieved through uneven labour burdens and fragile institutional arrangements.\u003c/p\u003e\n\u003cp\u003eBy integrating the Informal Green Ecosystem perspective with the Green Optimum Economy framework, the paper advances a conceptual contribution that bridges empirical groundedness with normative inquiry. The Green Optimum Economy is operationalised not as a policy blueprint, but as a heuristic for understanding how ecological integrity, economic viability, and social equity are continually negotiated within uneven urban contexts. This integration foregrounds trade-offs, power relations, and contestation as central features of urban sustainability transitions, rather than anomalies to be resolved through technical optimisation. Rather than offering a policy blueprint, the Green Optimum Economy provides secondary cities with a critical lens for interpreting and governing informal green ecosystems under conditions of uneven power and limited institutional capacity.\u003c/p\u003e\n\u003cp\u003eThe Khon Kaen case also underscores the importance of hybrid governance in shaping the outcomes of informal food systems. Municipal support created space for experimentation without full formalisation, yet inclusion within governance arrangements remained conditional and uneven. These dynamics highlight the need for urban policy approaches that recognise informal systems as part of core urban infrastructure while addressing structural vulnerabilities and power asymmetries, rather than treating informality as either a problem to be eliminated or a solution to be celebrated.\u003c/p\u003e\n\u003cp\u003eWhile the findings are grounded in a single case study, their relevance extends beyond Khon Kaen. Many secondary cities across the Global South share similar characteristics: limited planning capacity, fragmented food supply chains, and high levels of informality. The analytical framework developed in this paper offers a way to interpret these conditions and identify leverage points for more equitable and sustainable urban food transitions, without assuming universal models or best practices.\u003c/p\u003e\n\u003cp\u003eFuture research could build on this work by examining the long-term trajectories of informal green food ecosystems, particularly their capacity to endure beyond moments of crisis and their interaction with evolving regulatory regimes. Comparative studies across secondary cities would further illuminate how different political, institutional, and cultural contexts shape the possibilities and limits of informal food governance.\u003c/p\u003e\n\u003cp\u003eIn conclusion, this paper argues that advancing urban food security in the Global South requires taking informality seriously—not as an exception to be managed, but as a constitutive element of urban life. Recognising informal green food systems as critical urban infrastructure, while confronting their embedded inequalities, is essential for navigating the contested terrain of urban sustainability transitions.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eDeclaration of competing interest\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe author declares no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDeclaration of Generative AI Use\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe author used generative AI tools to support language refinement, structural organisation, and editorial clarity during manuscript preparation. All AI-assisted outputs were carefully reviewed and substantively edited by the author. The author takes full responsibility for the originality, accuracy, and scholarly integrity of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research was financially supported by the Program Management Unit on Area-Based Development (PMU A) [A15F640034] and by King Mongkut's Institute of Technology Ladkrabang [KREF206606].\u003c/p\u003e"},{"header":"References","content":"\u003cp\u003eA. ALLEN, L. G., AND C. JOHNSON. (ed.) 2017. \u003cem\u003eEnvironmental Justice and Urban Resilience in the Global South.,\u003c/em\u003e New York, NY, USA.: Palgrave Macmillan.\u003c/p\u003e\n\u003cp\u003eABU HATAB, A., CAVINATO, M. E. R., LINDEMER, A. \u0026amp; LAGERKVIST, C.-J. 2019. 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(ed.) 2015. \u003cem\u003eUrban food systems\u003c/em\u003e: Routledge.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Urban food security, informal urbanism, green optimum economy, peri-urban agriculture, green logistics, tactical urbanism, secondary cities, informal green ecosystem","lastPublishedDoi":"10.21203/rs.3.rs-8693626/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8693626/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eUrban food insecurity is an increasingly pressing challenge in secondary cities of the Global South, where fragile supply chains, rapid urbanisation, and uneven urban governance disproportionately affect low-income populations. This paper examines how Khon Kaen, a secondary city in Northeastern Thailand, developed an informal green food ecosystem that supports urban food security and ecological transition through peri-urban agriculture, informal markets, green logistics, and community-based initiatives. The study operationalises a Green Optimum Economy framework, emphasising negotiated balances between ecological integrity, economic viability, and social equity.\u003c/p\u003e\n\u003cp\u003eUsing a mixed-methods action research design that integrates food value-chain mapping, participatory action research, an Urban Lab approach, and tactical urbanism, the study analyzes upstream–midstream–downstream dynamics in Khon Kaen’s organic vegetable system. Empirical work involved collaboration with peri-urban producers, mobile vendors, green markets, local restaurants, school canteens, and vulnerable groups to prototype locally embedded mechanisms such as green logistics and small-scale green entrepreneurship.\u003c/p\u003e\n\u003cp\u003eThe findings demonstrate that informal and semi-formal food networks function as critical urban infrastructure, particularly during periods of disruption. During the COVID-19 pandemic, these networks enabled continued food access when conventional supply chains were destabilised, revealing both adaptive capacity and underlying precarity. The pandemic thus served as a stress test, exposing structural vulnerabilities and risk redistribution within urban food systems.\u003c/p\u003e\n\u003cp\u003eThe paper contributes by conceptualising the Informal Green Food Ecosystem in secondary cities, applying the Green Optimum Economy as a critical analytical lens beyond formal planning, and deriving insights for governing informal food systems as contested arenas of urban sustainability transitions.\u003c/p\u003e","manuscriptTitle":"Urban Food Security and Informal Green Ecosystems in Secondary Cities:\nNegotiating Sustainability through the Green Optimum Economy","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-05 05:32:35","doi":"10.21203/rs.3.rs-8693626/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"9a43e8e9-0bf7-4b50-b142-21a9d61dce62","owner":[],"postedDate":"February 5th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":61807273,"name":"Earth and environmental sciences/Environmental social sciences/Sustainability"},{"id":61807274,"name":"Scientific community and society/Agriculture"}],"tags":[],"updatedAt":"2026-02-24T16:41:31+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-05 05:32:35","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8693626","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8693626","identity":"rs-8693626","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}