The research team, led by Janet Tapkigen of Tampere University together with colleagues from the Kenya Medical Research Institute, King’s College London, and Tampere University, set out to map how the drivers of Nairobi’s food system interact and how different stakeholders experience them. Using the High Level Panel of Experts (HLPE) framework as an analytical scaffold, the researchers conducted focus group discussions, in-depth interviews, and key informant interviews with 42 participants drawn from Nairobi’s major markets, county government sectors, and research institutions. Through deductive and inductive content analysis of the transcripts, they identified fifteen distinct drivers shaping the city’s food system, ranging from climate change and infrastructure to globalisation, social media, and cooking fuel availability.

What makes the findings striking is that climate change did not appear as a single isolated pressure. It cut across nearly every other driver the researchers documented, acting as what the authors describe as a cross-cutting force that amplifies existing weaknesses throughout the supply chain. Heavy rains in food-producing regions such as Garissa cut off roads and destroyed crops, reducing the flow of produce into the city. Flooding disrupted planting cycles, forcing farmers to harvest prematurely and creating humid storage conditions favourable to aflatoxin growth, a hidden food safety threat that participants said often goes unnoticed until contaminated food reaches consumers. Damaged roads then forced traders onto longer alternate routes, hiring tractors at additional cost, expenses that were passed directly down the supply chain to shoppers in the form of higher prices.

The study’s systems mapping revealed that the largest number of drivers converge at the point of food retail and consumption, where their combined effects land hardest on food availability, affordability, and accessibility. This convergence helps explain a troubling cascade documented by participants: climate-driven shortages raise prices, rising prices push low-income households away from fresh produce toward cheaper, energy-dense processed foods, and that dietary shift in turn elevates the risk of diet-related noncommunicable diseases such as obesity and diabetes. One researcher interviewed for the study captured the substitution logic plainly, noting that when fruit and vegetables become inflated in cost, consumers choose bread over oranges, shifting toward processed options that carry long-term health consequences.

Equally revealing is how differently the various stakeholder groups perceived the same system. Retailers and young people working in the markets focused on climate impacts as disruptions to supply chains, prices, and the availability of goods. Experts and policymakers, by contrast, emphasised the effects of climate change on agricultural productivity. Community members highlighted food prices and economic constraints above all. Policymakers singled out land issues and inadequate policy frameworks, while experts flagged globalisation, urbanisation, and advertising as forces reshaping dietary habits. These divergent perceptions, the authors argue, are not noise to be averaged away but essential information, because they reflect each group’s position, power, and vulnerabilities within the food system itself.

That question of power runs through the paper’s most consequential argument. The researchers found that stakeholders’ roles and positioning within the city’s food system determine which impacts occur, which drivers are considered influential, and whose vulnerabilities persist. Youth and retailers, embedded in food retail and distribution, centred their concerns on access and affordability. Policymakers, oriented toward economic growth, prioritised productivity. Meanwhile, the informal food system that provides over 80 percent of Nairobi’s food distribution, retail, and purchases remains poorly integrated into formal regulatory frameworks, leaving it exposed to supply chain disruptions and limiting its capacity to deliver safe, nutritious diets. The study traces this structural stagnation to historical roots: Nairobi’s major markets, including Wakulima and City Market, have undergone minimal development since the 1960s, and planned expansions from 1970 were never implemented.

The technical details of the food supply chain illustrate how inefficiencies compound at every stage. Food travels from farms to primary markets on earth roads before continuing to Nairobi on tarmac, distributed informally by trucks, carts, private vans, passenger buses, and motorcycles. Packaging relies on sacks and crates, sometimes repurposed fertiliser sacks that can introduce harmful chemicals, and open vans expose produce to dust, exhaust fumes, and weather. Along this long chain of rural brokers, wholesalers, city intermediaries, and retailers, multiple taxation points drive up transaction costs, spoilage, and waste. One policymaker estimated that as much as 80 percent of what is produced never reaches a fork, ending up instead in landfills, roadsides, and dump sites, where it contributes to methane emissions.

Governance failures emerge as a decisive constraint on transformation. Although Kenya’s 2010 constitution devolved significant powers, resources, and functions such as agriculture and health to 47 counties, participants reported that the national government remains the primary lead and that sectoral policies often fail to address food systems because of limited awareness of how different sectors can contribute. Implementation of both sectoral and intersectoral policies is hampered by inadequate funding, limited capacity, transitioning governments, staff shortages, and resistance to change within departments. Kenya, like few other countries in the WHO Africa region, lacks food-based dietary guidelines, and although a food environment policy was drafted in 2018, participants described it as weak, with consumer awareness remarkably low. Unregulated television advertising was flagged as a particular concern, with one researcher reporting that roughly 40 percent of advertisements at peak viewing times promoted unhealthy foods.

Despite these entrenched problems, the study does not conclude that transformation is impossible, only that it remains limited under current conditions. The authors identify potential pathways including investment in cold-chain infrastructure, regulatory frameworks for the informal food sector, shortened supply chains, and strengthened intersectoral coordination across county boundaries, which is essential given Nairobi’s dependence on food from a broad geographic hinterland. They also extend the HLPE framework itself, arguing that while it offers a valuable systems-based approach, it requires local adaptation: it does not sufficiently unpack how political processes shape the entire system, nor does it capture the specific mechanisms and conditions under which drivers interact. The researchers recommend that future analyses explicitly map who holds power and how that power shapes priorities in practice.

The broader lesson extends well beyond Nairobi. Because food system drivers interact rather than operate in isolation, the authors argue that interventions must target combinations of active drivers within a specific context, demanding multisectoral collaboration and a genuine systems perspective. Siloed policies, they warn, are likely to prove ineffective unless the connections between climate, infrastructure, economy, and governance are addressed together, an approach consistent with frameworks such as Health in All Policies. For the millions of rapidly urbanising cities across sub-Saharan Africa, where over half the region’s population is projected to live in urban areas, the message is clear: global food system trends provide the backdrop, but it is local perceptions, local power dynamics, and local realities that determine whether transformation actually happens, and for whom.

Subject of Research: Stakeholder perceptions of the drivers and interactions shaping Nairobi's informal urban food system

Article Title: Do global food system trends reflect local realities? Perceptions of stakeholders

Article References: Tapkigen, J., Kaduka, L., Mbuka, S., Pulkki, J., Harding, S., & Koivusalo, M. (2026). Do global food system trends reflect local realities? Perceptions of stakeholders. PLOS Sustainability and Transformation, 5(10), e0000287. https://doi.org/10.1371/journal.pstr.0000287

Image Credits: AI Generated

DOI: 10.1371/journal.pstr.0000287

Keywords: urban food systems, Nairobi, climate change, food security, informal food sector, HLPE framework, food governance, stakeholder perceptions, sub-Saharan Africa, diet-related noncommunicable diseases, food supply chains, intersectoral policy

Urban areas facing siege present a unique and often overlooked nexus of vulnerabilities. Unlike rural regions, where agriculture can depend on expansive lands and relatively stable access to natural resources, cities under duress are constrained by limited space, fractured infrastructure, and disrupted supply chains. These limitations complicate traditional food production techniques and demand innovative solutions tailored to dense urban landscapes. The integration of specialized seed varieties, optimized land use strategies, and innovative water management promises a paradigm shift in humanitarian intervention.

Central to this transformation is the refinement of seed technology specific to siege conditions. Seeds are not merely carriers of genetic material; they embody resilience against environmental stresses such as soil salinity, erratic water availability, and elevated pollutant levels often present in war-torn urban soils. The development and deployment of seed variants capable of thriving in compact, damaged plots with minimal resource input enable local populations to produce food where conventional agriculture would be unfeasible. These seeds incorporate traits such as drought tolerance, rapid maturation cycles, and resistance to urban contaminants—elements crucial for survival under siege.

Land management in urban conflict zones requires a nuanced understanding of landscape fragmentation and soil degradation processes exacerbated by warfare. Bombardments, construction ruin, and mass displacement disrupt the soil’s physical and chemical properties, reducing fertility and water retention capabilities. Advanced soil remediation techniques, including biochar application, phytoremediation, and micro-mulching, are essential to restore productivity in these degraded soils. Furthermore, strategic land allocation plans focus on maximizing micro-farming plots, rooftop gardens, and reclaimed vacant lots to optimize food production without exacerbating overcrowding or triggering additional conflict.

Water management represents perhaps the most formidable challenge in besieged urban contexts. Traditional irrigation infrastructures often fall victim to destruction or neglect, leaving urban farmers reliant on scarce and unpredictable water sources. Innovative interventions, therefore, emphasize water harvesting, recycling, and conservation technologies that integrate with limited urban spaces. For instance, greywater recycling systems recycle household wastewater for irrigation, reducing dependence on municipal supplies. Meanwhile, rainwater harvesting installations capitalize on sporadic precipitation, storing vital water reserves during dry spells. Collectively, these strategies address water scarcity and quality issues, thereby sustaining agricultural productivity.

The convergence of seed, land, and water management technologies further extends into integrated urban food production systems. Hydroponics and aquaponics have emerged as viable alternatives that circumvent traditional soil dependence, leveraging nutrient-rich water solutions to grow crops vertically in confined spaces. Coupled with seed varieties bred for hydroponic systems, these methods offer scalable, resource-efficient options for food production in areas where soil contamination or space limitations preclude conventional agriculture. Such systems have an added benefit of being less visible targets during conflict, thus maintaining a measure of protection for food sources.

Equally critical to these technical advancements is the socio-political framework supporting humanitarian interventions. Effective deployment hinges on coordination among local communities, NGOs, and international agencies to ensure that innovations align with cultural practices, security considerations, and logistical realities. Empowering local populations through training and participatory planning enhances resilience and fosters a sense of ownership, which is vital in sustaining food production when external aid becomes intermittent or ceases. This bottom-up approach helps bridge the gap between cutting-edge science and on-the-ground practicality.

Digital technologies bolster these efforts by providing real-time data analytics and geospatial mapping to optimize resource allocation and monitor environmental conditions. Satellite imagery, combined with ground-level sensors, enables precise assessment of land degradation, water availability, and crop health, informing adaptive management strategies. These tools also facilitate transparency and accountability, allowing humanitarian agencies to evaluate intervention efficacy dynamically and adjust tactics swiftly as conflict conditions evolve.

The environmental implications of urban siege extend beyond immediate human concerns, touching on broader ecosystem dynamics. The pollution arising from urban conflict—chemical residues, heavy metals, and particulate matter—compounds risks to soil, water, and human health. Addressing these toxic legacies through integrated remediation techniques contributes to long-term sustainability, ensuring that urban agriculture post-conflict can thrive rather than perpetuate cycles of contamination and disease. This acknowledgment repositions humanitarian interventions not just as emergency responses but as crucial contributors to urban ecological restoration.

Interdisciplinary research plays a pivotal role in synthesizing knowledge across agronomy, urban planning, hydrology, and social sciences to shape holistic solutions. Recent studies employ scenario modeling to forecast how various seed, land, and water management combinations can perform under different siege intensities and durations. These predictive models guide decision-makers in prioritizing interventions with the highest likelihood of success and identifying potential unintended consequences. By embedding scientific rigor into humanitarian planning, interventions become more strategic, efficient, and resilient.

Challenges persist, notably around access constraints in siege zones where active hostilities impede movement and resource transport. Innovative logistical frameworks leveraging drones, local networks, and decentralized supply chains are under exploration to circumvent blockades and maintain the flow of essential agricultural inputs. The imperative to navigate these complex terrains underscores the need for flexible, context-specific solutions over one-size-fits-all models, embracing adaptive management as a core principle.

The holistic approach to food security in besieged urban environments, centered on enhancing seed, land, and water management, aligns closely with global imperatives such as the United Nations Sustainable Development Goals. It advances targets around zero hunger, clean water and sanitation, sustainable cities, and climate action. In this sense, the endeavor transcends immediate crisis response, contributing to resilient urban futures capable of withstanding conflict shocks and environmental uncertainties.

Ethical considerations also arise regarding the prioritization of urban agriculture under siege. Allocating limited resources to seed and water management must balance immediate humanitarian relief—such as medical aid and shelter—and long-term sustainability efforts. Integrating ethical frameworks into planning processes ensures that interventions respect human rights and equitable access, mitigating the risk of exacerbating inequalities within already vulnerable populations.

Testimonials from field operations reveal that communities engaging in enhanced seed, land, and water management report not only improved food availability but also positive psychosocial outcomes. The ability to cultivate crops amidst adversity rekindles hope, autonomy, and social cohesion. These intangible benefits serve as powerful incentives for sustaining agricultural initiatives beyond conflict phases, reinforcing the transformative potential of these scientific and technical advancements.

Looking ahead, advancing research on seed genetics tailored to urban conflict zones continues to evolve, with emerging gene-editing technologies offering prospects for even greater adaptability and yield. Coupling these innovations with smart irrigation systems powered by renewable energy can create localized, self-sufficient urban farms resilient to siege-induced disruptions. Cross-sector partnerships between academia, governments, and private sectors will be essential to accelerate these developments from laboratory to field implementation.

In conclusion, the integration of enhanced seed, land, and water management within humanitarian interventions embodies a revolutionary stride toward addressing urban food insecurity under siege. By tackling the multifaceted challenges imposed by conflict and urban density, these approaches provide scalable, sustainable pathways for survival and regeneration. This paradigm shift not only redefines humanitarian aid but also charts a hopeful trajectory for cities caught in the crossfire, transforming them from barren battlegrounds into bastions of resilience and life.

Subject of Research: Enhancing seed, land, and water management techniques to improve humanitarian food security interventions in urban areas under siege.

Article Title: Enhancing seed, land and water management in humanitarian interventions for urban areas under siege.

Article References:
Adam-Bradford, A. Enhancing seed, land and water management in humanitarian interventions for urban areas under siege. Nat Water (2025). https://doi.org/10.1038/s44221-025-00556-y

Image Credits: AI Generated