How cities can build stronger food systems through smarter urban agriculture policy

Urban food systems are under increasing pressure due to rising inequality, climate stress, and volatile supply chains, prompting cities to explore local production as a way to strengthen food security. While urban agriculture is often promoted through subsidies and support programs, evidence on which policies deliver lasting results remains limited.

That issue is addressed in new research, Agent-Based Modeling of Urban Agriculture: Decision-Making, Policy Incentives, and Sustainability in Food Systems, published in Complexities. Using a simulation-based approach, the study evaluates how education campaigns and financial incentives influence the growth and stability of urban agriculture markets.

The findings suggest that policy design, particularly the balance between financial incentives and behavioral change, plays a decisive role in shaping sustainable outcomes.

Modeling urban agriculture as a complex adaptive system

Urban food systems behave as complex adaptive systems. In such systems, outcomes are not determined by single actors or linear cause-and-effect relationships, but by the interaction of many agents whose decisions evolve over time. Traditional policy analysis tools, the authors argue, often struggle to capture these dynamics, leading to interventions that underperform once implemented in real-world settings.

To address this gap, the researchers use agent-based modeling, a simulation approach that allows individual actors to be represented as autonomous decision-makers. In the model, urban space is populated by two main types of agents: producers and consumers. Producers decide whether to enter or exit the urban agriculture market based on expected profitability, costs, and policy incentives. Consumers choose where to purchase food based on price sensitivity, preferences, income, and social influence.

These agents interact repeatedly over time, generating system-level patterns such as market share, income distribution, and resilience to shocks. By running the model under different policy scenarios, the authors are able to observe how small changes in incentives or behavior can produce large and sometimes unexpected effects at the market level.

The study is based on the Brazilian urban context, where rapid urbanization has intensified pressure on food systems while also creating opportunities for localized production. However, the authors emphasize that the modeling framework is adaptable and relevant to cities facing similar challenges globally.

Education campaigns outperform subsidies in building sustainable markets

The researchers test three main types of interventions: education-based campaigns aimed at shifting consumer preferences, subsidies for urban agriculture producers, and subsidies for consumers purchasing locally produced food.

Across multiple simulation runs, education campaigns consistently outperform subsidy-based approaches in expanding the market share of urban agriculture. By increasing consumer awareness and social acceptance of locally produced food, these campaigns drive demand without requiring ongoing public expenditure. As consumer preferences shift, producers respond by entering the market, creating a self-reinforcing cycle of growth.

Producer subsidies also generate positive outcomes, particularly in stabilizing participation among urban farmers and reducing income inequality within the producer population. However, these benefits come at a fiscal cost, raising questions about long-term sustainability. The study finds that while subsidies can accelerate market formation, they may also create dependency on public funding if not paired with demand-side interventions.

Consumption subsidies, by contrast, show weaker and less consistent effects. While they reduce prices for consumers in the short term, they do not significantly alter long-term purchasing behavior or market structure. Once subsidies are removed, demand tends to revert, limiting their effectiveness as a standalone policy tool.

Policies targeting behavior and social norms can be more impactful than purely financial incentives. By influencing how consumers value local food, education campaigns help embed urban agriculture into everyday purchasing decisions, making the market more resilient over time.

Equity and resilience shape the long-term impact of policy choices

The study strongly focuses on equity and resilience, two dimensions often overlooked in urban agriculture policy debates. The model tracks how income is distributed among producers and how the system responds to external shocks, such as sudden drops in production.

Education-based interventions emerge as particularly effective in promoting equitable outcomes. As demand grows organically, producers experience more stable income opportunities without the distortions associated with targeted subsidies. This reduces income inequality within the producer group and lowers barriers to entry for new participants.

Producer subsidies also contribute to equity by cushioning farmers against market volatility, but they risk concentrating benefits among those already positioned to access public support. The study highlights the importance of policy design in avoiding unintended exclusion or rent-seeking behavior.

Resilience analysis reveals another advantage of education-driven systems. When the model introduces production shocks, markets shaped by strong consumer preference for local food recover more quickly than those reliant on subsidies. This suggests that behavioral change enhances adaptive capacity, allowing the system to absorb and respond to disruption more effectively.

The authors interpret this finding as evidence that resilience in food systems is closely tied to social dynamics. Markets supported by shared values and norms are better equipped to adjust to stress than those sustained primarily through external financial support.

Implications for urban food policy and planning

While subsidies remain a common tool in agricultural policy, the research suggests that they may be less effective than often assumed when applied to urban contexts. Instead, interventions that shape consumer behavior and social perception may offer a more durable path to market development.

The authors warn, however, that education campaigns are not a quick fix. Their impact unfolds gradually, requiring sustained effort and coordination with producers, retailers, and community organizations. Yet once established, the resulting demand can support urban agriculture without continuous public spending.

The research also highlights the value of simulation-based policy analysis. By testing interventions in a virtual environment, policymakers can explore potential outcomes and trade-offs before committing resources. This approach is particularly valuable in complex systems where unintended consequences are difficult to predict.

Importantly, the study does not claim that urban agriculture alone can solve food insecurity or environmental challenges. Rather, it positions local food production as one component of a broader strategy that must account for social behavior, market dynamics, and institutional capacity.

The authors note that successful urban agriculture policy requires integration across domains, including education, urban planning, and social development. Policies designed in isolation are less likely to produce lasting change.