Research & reports

Gideon Baffoe, Philip Antwi‐Agyei · City and Environment Interactions · Ghana (Accra)

This mixed-methods study analyzed the role of urban agriculture (UA) in climate resilience in Accra, Ghana, from the perspective of policymakers. While UA contributes to food security, water use efficiency, and ecological protection, its integration into policy frameworks was found to be limited due to challenges such as weak institutional coordination, competing economic priorities, and governance inefficiencies.

Abdul Rahim Mohammed Sabtiu, Isaac Amankona Hinne, Isaac Kwame Sraku, Daniel Kodjo Halou, Richard Tettey Doe, Simon K. Attah, Fred Aboagye‐Antwi, Yaw A. Afrane · Malaria Journal · Ghana (Accra)

A study in Accra, Ghana, investigated mosquito larval habitats and their impact on Anopheles gambiae s.l. larvae density, conducting surveys at 15 locations during 2022's dry and rainy seasons. Of 727 potential habitats, 65.34% were positive for Anopheles larvae, with drainage ditches being the most common type. Irrigated urban farming sites showed the highest abundance of An. gambiae s.l. larvae, particularly during the rainy season, indicating that urban farming contributes to increased mosquito breeding habitats.

Emilie E. Ellis, S. Campbell, Jill L. Edmondson · Proceedings of the Royal Society B Biological Sciences · Global

A large-scale assessment across three cities found up to a 43% reduction in species richness of bees, hoverflies, and nocturnal moths in urban horticultural sites along urbanization gradients. These declines are driven by taxon-specific landscape changes like reduced tree canopy and semi-natural habitat. Moths and hoverflies were particularly sensitive to urbanization compared to bees, indicating a wide range of pollinators are under threat in urban landscapes.

Blessing Nyamasoka‐Magonziwa, Esther Simango, Hatirarami Nezomba · Frontiers in Agronomy · Zimbabwe (Chitungwiza)

This study evaluated climate-smart crop production practices by urban farmers in Chitungwiza District, Zimbabwe, and their effects on household diets. Mixed methods research, including focus group discussions with four farmer groups and interviews with 107 households in 2022, classified only 23% of farmers as climate-smart. While climate-smart crop production positively influenced household diets, with climate-smart households having a significantly higher Household Dietary Diversity Score (3.3 vs. 2.9; p=0.02), there were no significant differences in maize yield between climate-smart and non-climate-smart farmers (2.10 t/ha vs. 2.27 t/ha, respectively, in the 2020/2021 season).

Jelena Salmi, Anna Krzywoszynska · Environmental Science & Policy · Finland

A discourse analysis of 103 governance and grey literature documents in Finland examined the politics of soil biodiversity indicators. The study found that eDNA is the preferred scientific basis for soil biodiversity governance in Finland due to alignment between scientific and policy groups. However, land workers' organizations criticize eDNA methods, arguing they risk obscuring local specificity and creating environmental and social injustice, potentially alienating land management groups.

Cristian Granados Martínez, Meyer Guevara-Mora, Eugenia López‐López, José Rincón Ramírez · Water · Colombia

This study evaluated aquatic macroinvertebrate community structure in the Ranchería River, Colombia, across conserved, urban/agricultural, and mining zones during the dry season (January–March 2021). Urban/agricultural zones showed the lowest richness (35 genera) and were characterized by disturbance-tolerant species, particularly Melanoides. Land use types constituted the primary driver of community structure, with a 24.1% pure effect, exceeding physical, chemical, and land cover variables.

Magboul M.S. Siddig, Stephen Boahen Asabere, Abdullah S. Al-Farraj, Eric C. Brevik, Daniela Sauer · Journal of Hazardous Materials Advances · Sudan

This systematic review and meta-analysis examined 76 publications on soil heavy metals in Sudan published between 1996 and 2024, assessing concentrations of 10 heavy metals (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Zn) and potential ecological risk index (PERI) across 9 land-use types including urban agricultural, industrial, roadside, tannery, waste dump, rural agricultural, coastal sediment, gold mining, and river sediment areas. Average heavy metal levels across all land uses exceeded common soil ranges, with Cd, Cr, Cu, Hg, Ni, and Pb surpassing WHO/FAO limits. In urban agricultural soils, Cd averaged about 158 times and Hg about 340 times typical background ranges, while industrial, gold mining, and waste dump land uses exceeded a serious ecological risk threshold (PERI greater than 900). Cd and Hg together accounted for over 70% of PERI in waste dump and gold mining sites.

Álvaro Luis José Reyes Córdova · Horizontes Amazónicos · Ecuador

A bibliographic review of research on water quality in the Puyo River and its tributaries in Pastaza, Ecuador, compiled studies from scientific databases and institutional repositories reporting physicochemical, microbiological, and heavy metal parameters. The main sources of contamination were found to be wastewater discharges, fecal coliforms, and accumulation of heavy metals such as lead and mercury linked to urban, agricultural, and mining activities, with community perception aligning with technical findings as most of the population rated the water poor quality and associated it with health problems. Over the past twenty years, a progressive deterioration in water quality parameters has been documented, with increases in turbidity and pathogenic microorganisms despite some isolated recovery efforts, and the review concludes that lack of attention from the municipality and prefecture, together with the absence of continuous monitoring, is worsening the water crisis and demands comprehensive, participatory governance.

Sumit Vij, Vishal Narain · Wiley Interdisciplinary Reviews Water · Global

This review addresses a knowledge gap on how peri-urban residents in Asia and Africa adapt to the impacts of urbanization and climate change on water security. As rural-urban boundaries rapidly blur in the global South, peri-urban spaces are characterized by weakening access to water resources, depleting common property institutions and poor civic engagement, and the review presents the persistent marginalization of peri-urban residents from a water security perspective, while also showing that they do develop adaptation measures. Existing literature is found to focus primarily on (1) increased vulnerability of peri-urban agriculture and allied sectors, (2) barriers and enablers to water-security-related adaptation planning, and (3) justice in peri-urban areas, and the review calls for further study of emerging cooperation and collective action that could reduce conflicts between peri-urban and urban inhabitants and improve water security.

Abdul-Salam Ibrahim, Marney E. Isaac, Thembela Kepe · Land Use Policy · Ghana

Focusing on Ghana, where floods driven by urbanization and climate change are destabilizing urban systems in which land tenure is integral, this study drew on political ecology and land-tenure-security frameworks to examine how floods affect the land tenure security of flood victims. Based on semi-structured interviews with flood victims and planning officials, it found that flood-induced rezoning and new planning schemes, tenant insecurity, relocation, loss of land documents, and threats to urban agriculture all affect flood victims' land tenure security; possessing land documents was found to be important for tenure security but not an absolute condition for victims' perceived security. Post-flood land-use planning for flood risk management was found to have dual potential — it can enhance tenure security and bolster community resilience, but when carried out in an exclusionary way that overlooks the urban poor, it can instead perpetuate inequality and tenure insecurity. The study recommends tenure-responsive land-use planning that embeds contextual, procedural, and distributive equity principles into planning responses to urban floods.

Pierre‐Alexandre Deyris, Franck Pélissier, Claire M. Grison, Claude Grison · Journal of Hazardous Materials Advances · Global

Herbicide use worldwide has doubled over the past 30 years, and diuron contamination of tropical aquatic ecosystems — affecting food crops such as pineapple — has been reported across Southeast Asia, the Pacific, and Africa. This perspective article examines taro (Colocasia esculenta), a widely cultivated crop whose tubers are consumed locally, as a nature-based means of mitigating diuron impact on tropical aquatic ecosystems through rhizofiltration, i.e., phytoaccumulation of the herbicide by the roots. Analysis of treated tubers found that diuron levels in the tuber core were below recommended European standards, indicating the tubers could remain edible for the local population and confirming compatibility with existing food uses.

Ioana Florea · · Global

This chapter finds that while collective urban gardening projects represent forms of resistance against market-based food systems, the precarization of urban natures, and real-estate dominance, their everyday practices often fail to deliver on these ideals and intentions, generating incomplete, contradictory, or temporary results. It proposes a heuristic frame linking space, time, and class to review prior urban-gardening research from a political-ecology perspective, tracing how space's materiality, time embedded in plant growth, and class differences conditioning gardeners' access to space and time produce these contradictions.

Jan Grossarth · Discover Cities · Global

This paper critically examines the dominance of quantification—certification scores, KPIs, life-cycle assessment—in sustainability practice for cities and buildings (including urban agriculture), arguing that data-driven metrics strip out the emotional and narrative meaning of sustainability. The authors label the shift from a culturally rich orientation to a purely technical, quantitative practice a "tragedy of sustainability," and argue that narrative-focused interviews and real-life storytelling in architecture and urban planning should not just accompany KPIs and ratings but be prioritized over them. The paper is a conceptual argument, not an empirical study with data or case findings.

Augustin Tshilumba Ilunga, Michel Mbumba Bandi, Albert Tshinyama Ntumba, Damien-Joseph Muteba Kalala · Revue Africaine d’Environnement et d’Agriculture · Democratic Republic of Congo

A study of urban agriculture in Kinshasa, Democratic Republic of Congo—a sector described as vital for food security and employment amid rapid urbanization, food insecurity, and unemployment, where farms face significant challenges including land pressure, restricted access to credit, and lack of institutional support. The study aimed to (i) examine the motivations of agri-entrepreneurs, (ii) assess their impact on farm viability, and (iii) identify the economic and non-economic factors influencing business sustainability, using a qualitative and quantitative survey combining 20 semi-structured interviews across three peripheral zones (via snowball sampling) with documentary analysis. Three categories of entrepreneurs were identified: civil servants farming as a supplementary activity, private-sector employees investing in farming, and traders farming to secure their survival. Non-pecuniary motivations such as social engagement and passion strengthened resilience, but land insecurity, a financing deficit, and lack of training were identified as the major obstacles farms face; observed adaptive strategies included diversification and informal partnerships. The study concludes by calling for integrated strategies to secure land tenure, facilitate access to credit, and professionalize the sector while integrating peri-urban agriculture into urban planning processes.

Edwin Javier Ortega Zúñiga · Ediciones Comunicación Científica eBooks · Colombia

A study of Palmira, Colombia — a city with a long tradition as the country's agricultural capital — finds that it nonetheless faces significant food insecurity. Prior research reviewed in the study attributes this to an aging rural population and young people's declining interest in farming (which has shrunk the available labor force and limited adoption of new technology), gender inequality that restricts women's access to agricultural resources and decisions, climate change impacts such as droughts and floods on production, and accelerated urbanization that has reduced cropland and fragmented the agricultural landscape. As a potential response, the study describes a pilot project at four sites in the city that installed small-space vegetable production systems, which it reports functioned as a viable source of fresh food in dense urban settings. The authors call for a multidisciplinary approach combining social, economic and environmental factors to address food insecurity in Palmira.

Parisi A., Walthall B., Clerino P., Firmbach P., Onyszkiewicz M., Vicente Vicente J. L. · Environmental Evidence · Global

A protocol for a systematic map of the scholarly literature on the relationship between urban agriculture (UA) and gentrification. The authors note that existing accounts variously present gentrification as a possible outcome of UA activities, as a risk that UA initiatives themselves face, and as other kinds of relationship, and argue that these divergent accounts are partly explained by different theoretical engagements with gentrification and by the breadth of activities gathered under 'urban agriculture'. It sets out the search and review strategy and aims to expose gaps in dominant academic discourses. Being a protocol, it reports no findings yet.

Jennifer Newell, Siobhan Cox, Rory Doherty · Urban Agriculture & Regional Food Systems · Global

A systematic review synthesized literature on the oral bioaccessible fraction (BAF) of arsenic, cadmium, chromium, nickel, and lead in vegetables grown on contaminated soils, drawing values from multiple online databases across potentially toxic elements (PTEs), in vitro test methods, and vegetable types. The review starts from the premise that many urban and peri-urban brownfield sites carry a legacy of soil metal and metalloid contamination, so crops grown there may pose human health risks. Median PTE BAFs ranked Cd > Ni > Cr > As > Pb; among in vitro methods, the unified BARGE method (UBM) produced the highest median BAFs (63.0% gastric, 59.6% gastrointestinal); and by crop type, BAFs ranked non-vegetables (e.g., rice, fungi) > legumes > root vegetables > bulb vegetables > leafy vegetables.

Kelley AT, Boger R · EcoHealth · 米国・ニューヨーク市ブルックリン

A survey of mosquito larval abundance and genera across 22 community gardens in Brooklyn, New York. The authors frame these gardens as social spaces providing food sovereignty to many New Yorkers, while the arrival of Aedes albopictus and the longtime presence of Culex pipiens make socialising in them more dangerous — Ae. albopictus is associated with dengue, Zika and chikungunya, and Cx. pipiens is a longstanding West Nile virus vector. Because both breed in human-made plastic containers, knowing their preferred container types and locations can inform gardeners' best management practices. Non-purposeful container types and lower total volumes of water were significant predictors of higher mosquito densities, though these variables did not predict egg-laying preference.

Ministry of Sustainability and the Environment, Singapore · Ministry of Sustainability and the Environment, Singapore · Singapore

On 26 September 2025, Minister Grace Fu replied to a parliamentary question on progress toward the "30 by 30" goal, stating that less than 10% of Singapore's food consumption is currently produced domestically. She called the goal "aspirational," set before COVID-19 under more favourable conditions, while noting locally produced hen eggs exceed 30% and beansprouts exceed 50% of local consumption, and that the alternative protein industry faces high energy costs and insufficient consumer acceptance.

Bauer W., Titz A. · Nature-Based Solutions · Malawi (Lilongwe)

Urban Nature-based Solutions (NbS) are promoted globally as multifunctional and cost-effective, and municipal interest is growing in cities of the so-called Global South. Yet research remains clearly biased toward the Global North, with particularly few studies on cities in Sub-Saharan Africa — leaving a high risk that maladapted NbS, modelled on examples from elsewhere that do not meet local requirements, get adopted. This article examines the barriers to adopting urban NbS in Malawi's cities and the opportunities for successful implementation, drawing on qualitative data (workshops, narrative expert interviews, group discussions) gathered over five research stays in Lilongwe between 2022 and 2024, and analysing in detail the strategies used by those implementing the Lilongwe Ecological Corridor Initiative (LECI), a large-scale NbS in the capital.

Abdulhakeem Al-Qubati, Lulu Zhang, Matthias Forkel · Sustainable Cities and Society · Global

This 2024 global review examined 96 studies focusing on methods for estimating carbon sequestration (CS) and emissions in urban and peri-urban agriculture (UPA). The review found significant research gaps: most studies were in the global north, research in the global south is lacking, and there are fewer studies on CS compared to GHG emissions. Additionally, few studies jointly assessed water and carbon cycles, and spatiotemporal analysis, modeling, and remote sensing for GHG emissions are underutilized.

Aikaterini Kouloumprouka Zacharaki, James Monaghan, Jennifer R. Bromley, Laura H. Vickers · Plants People Planet · Global

This review identifies challenges for strawberry cultivation in urban production systems, noting that new urban farmers often lack the specialist knowledge of commercial growers. Common bottlenecks include plant physiology, pathogen management, choice of propagation material, fertigation, pollination, and environmental requirements. This knowledge gap appears to result in the abandonment of strawberries as a crop of choice in urban systems.

José Luis Chaves, Alexandre Boleira Lopo, G. M. OLIVEIRA, J. F. ARAÚJO, Luciano Sérgio Ventin Bomfim, J. A. CASTRO · Editora Científica Digital eBooks · Global

This systematic review investigated the viability of animal production in urban and peri-urban agriculture as a tool for food security, using the PRISMA methodology. The review found that while this practice offers benefits like domestic food security and income generation, it also presents negative aspects such as odors, noise, and the transmission of zoonoses. Public policies are needed to regulate the activity and minimize health risks.

Mascha Gugganig · Science Technology & Human Values · Global

This paper explores the arguments and internal disagreements among experts popularizing vertical farming (VF), an emerging urban food production system. While VF is promoted for its space efficiency and independence from weather, it faces debates regarding its unsustainability and high energy costs for producing a limited range of perishable foods. Findings indicate that disagreements among vanguards reveal that VF is seen as one of many solutions, not the sole answer.

Prajal Pradhan, Daya Raj Subedi, Kshitij Dahal, Yuanchao Hu, Prakriti Gurung, Sijal Pokharel, Sagar Kafle, Biplav Khatri, Sudeeksha Basyal, Monika Gurung, Aruna Joshi · Cell Reports Sustainability · Global

This systematic analysis of 1,450 urban agriculture publications examined its impacts on Sustainable Development Goals (SDGs). It found urban agriculture is linked to all SDGs, with 142 targets showing positive sentiments and 136 showing negative sentiments, with positive sentiments roughly double the negative. The study concludes that urban agriculture does not inherently contribute to sustainability, as its impacts depend on specific practices and require tackling identified hurdles.