Research & reports

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.

Getachew Demissie Desta, Zeleke Gonfa Wordofa · International Review for Spatial Planning and Sustainable Development · Ethiopia

A study of the rate and direction of spatial expansion of Robe Town, Ethiopia, into surrounding rural kebeles, and its effect on the tenure security of peri-urban landholders. It combined socioeconomic data from 202 sampled household heads with spatial data from Landsat images taken in 1987, 2002, and 2020. The town grew annually by 18.6% (1984–1994), 11.3% (1994–2007), and 9.3% (2007–2020), with its total area rising from 5.1 km² in 1984 to 80.2 km², a 40.9% overall increase. Over the 33-year period, built-up area expanded fastest southward, reaching 9.91 km from the town's mean center, and grew from 4.38 km² in 1987 to 27.9 km² in 2020; about 10.2 km² of farmland was converted to built-up land between 1987 and 2020. In peri-urban areas of Robe town, 48.9% of landowners lost around half of their farmland, leaving peri-urban landowners feeling insecure about their tenure due to fear of eviction and expropriation at minimal compensation.

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.

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.

Ricard Segura, Johannes Langemeyer, Alba Badía, Sergi Ventura, Jaime Vila-Traver, Gara Villalba · The Science of The Total Environment · Spain (Barcelona)

A study in the Metropolitan Area of Barcelona, Spain, investigated the impacts of peri-urban agricultural expansion on the food-water-climate nexus using urban metabolism and atmospheric-biosphere models across four land-use scenarios. While expansion increased food production and irrigation water requirements, replacing natural non-forested and forest areas for peri-urban agriculture was predicted to reduce net ecosystem productivity by up to 18.5% and total carbon stocks by 3.3%. Irrigated peri-urban agriculture potentially reduced near-surface temperatures by 0.7°C, though reductions in the densest urban areas were minimal.

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.

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.

Laura S. Tuominen, Heikki Helanterä, Patrik Karell, Lauri Rapeli, Timo Vuorisalo, Jon E. Brommer · npj Urban Sustainability · Finland (Turku)

This before-after study in Turku, Finland, examined the influence of the COVID-19 pandemic on urban box gardening from 2019 to 2021. While box gardening's importance for resilience increased and gardeners remained motivated, participants reported receiving fewer benefits from gardening during the pandemic. This suggests a negative influence of the pandemic on well-being, extending to urban gardening outcomes.

Pierric Calenge, Maie Gérardot · Métropolitiques · United States (Cleveland)

The work by Max Rousseau and Vincent Béal illuminates the ambiguities of a policy that organizes urban decline and racial segregation in Cleveland. This policy promotes urban degrowth and racial segregation, balancing algorithmic management and urban greening. The study focuses on the Rust Belt region, which experiences de-urbanization marked by the subprime crisis, racism, and segregation.

Alexandre Chausson, Alison Smith, Ryne Zen-Zhi Reger, Brian O’Callaghan, Yadira Mori-Clement, Florencia Zapata, Nathalie Seddon · PLOS Climate · Global

This systematic review analyzed 66 reviews on the economic impact of nature-based solutions (NbS). Most reviews showed positive outcomes for income and employment, but those with critical appraisal of underlying studies reported more mixed outcomes. These results were influenced by factors such as the balance between short-term and long-term gains, market conditions, regional effects, reliance on subsidies, and discrepancies between expected and actual economic benefits. NbS delivered equal or better economic outcomes compared to alternatives and provided broader benefits like food security and flood protection, but improved monitoring of economic, social, and ecological outcomes and the development of comprehensive accounting systems are needed.

Cecil C. Konijnendijk · Edward Elgar Publishing eBooks · Global

This chapter examines the diverse uses of urban green spaces, encompassing recreation, biodiversity conservation, public health, and regulatory ecosystem services, with food production also re-emerging. Changing urban populations, including cultural diversity and ageing, have altered demands and uses. The study identifies a critical need to manage potential conflicts and trade-offs among these varied demands, despite many uses being able to coexist.

Nolwazi Z. Khumalo, Melusi Sibanda, Lelethu Mdoda · Sustainability · Sub-Saharan Africa

A systematic review and bibliometric analysis examined the implications of climate-smart agriculture (CSA) practices and climate adaptation strategies for food and income security in urban Sub-Saharan Africa. The review found that CSA practices boost urban food production and income, but also recognized critical challenges and trade-offs requiring urban agriculture transformation.

Laura E. Balis, Emily Shaw, Whitney Fung Uy, Katie Nelson, Maryan Isack, Laura Flournoy, Daniele Vest, Jessie Deelo, Amy L. Yaroch · Agriculture & Food Security · United States

This scoping review examined the environmental and health impacts of locally distributed specialty crops in the Midwestern United States, analyzing 9 grey and 19 peer-reviewed sources. While specialty crops positively impacted nutritional intake for diverse populations, the effectiveness of production practices on soil and plant quality and greenhouse gas emissions was mixed. The review concluded that more rigorous study designs with long-term follow-up are needed.

Yevheniia Varyvoda, Taylor Ann Foerster, Joona Mikkola, Matthew M. Mars · Sustainability · United States (Arizona)

This multi-method study in Southern Arizona, USA, explored the adoption of nature-based solutions (NbS) by local food entrepreneurs (LFEs) for climate adaptation. The findings revealed that existing NbS were primarily introduced through learning-by-doing practices, which were constrained by economic and technological resource limitations. Priority adaptation pathways identified for NbS included funding, financing, and knowledge co-creation, with LFEs likely to adopt NbS based on their ability to address climate issues and generate revenue.

Aashna Sinha, Kailash Bisht, Digvijay Singh · · Global

This article explores vertical hydroponic farming, noting its benefits like reduced space and water use, and enhanced robustness with Plant Growth-Promoting Microorganisms (PGPMs). However, it also demonstrated that the system's ecological impact is significantly affected by growing media, pots, electricity use, and transportation. The study suggests potential for reducing greenhouse gas emissions and abiotic resource decline by using fiber as growing medium and paper containers.

Miles P.A. Bate-Weldon, Jill L. Edmondson, Katie J. Field · iScience · Global

This study investigated the effect of urban environmentally relevant concentrations of zinc in soils on nutrient exchange between arbuscular mycorrhizal fungi and pea plants using radio-isotope tracing. It found that at higher zinc concentrations, the transfer of phosphorus from fungi to plants and carbon from plants to fungi dramatically decreased. The results suggest that while urban horticulture has potential for food production, the unchecked presence of contaminants like zinc in urban soils may critically hinder its realization.

Jeffrey Chiwuikem Chiaka, Gengyuan Liu, Hui Li, Wen Zhang, Mingwan Wu, Zhaoman Huo, F. Gonella · Environmental and Sustainability Indicators · Sub-Saharan Africa

This study evaluated land cover change and its drivers using spatial and statistical analysis in 22 designated protected areas (PAs) across the tropical coastal regions of sub-Saharan Africa. Results indicated that food production is prevalent in these protected areas regardless of their designation, and forest loss occurred in most PAs, suggesting weak conservation. Population density was the most significant driver of land cover change, and only 15 out of 22 protected areas showed an increase in their total ecosystem service value.

Holger Braun, Dorothee Apfel, Benedikt Rilling, Carsten Herbes · Cleaner and Responsible Consumption · Germany

A study with 44 hobby gardeners in Germany found that substrates are not a major part of gardeners' social interactions, and price is the dominant purchase criterion for substrates, with sustainability not playing an important role. Although basic knowledge about peat is widespread, purchasing substrates is a utility-driven process with mostly passive information behavior.

Mitchell McLarnon · · Global

This chapter describes the practice, processes, and ethical tensions of using cell phones for visual data collection, representation, and analysis in school/community garden research projects. The findings suggest that while gardens and cell phones have the potential for enhancing experiential learning, increased well-being, and ecological awareness, their use needs to be highly contextualized within critical discussions related to settler colonialism, consumerism, neoliberalism, and (green) gentrification.

Dongxiang Chen, Yuanming Wang, Haijun Bao · Habitat International · Global

This research extended the land sharing and sparing framework to urban land use, quantifying the impact of urban services, food production, and ecosystem services. The results showed that land-sparing scenarios had a 23.6% lower overall value loss than sharing scenarios on average. However, while land-sparing mitigates losses in food production and ecosystem services, it increases the cost of urban services, creating a trade-off that challenges achieving an optimal win-win situation.

László Csambalik, Izóra Gál, Krisztina Madaras, Andrea Tóbiás, Péter Pusztai · Urban Science · Global

This review examines soil-based urban agriculture and high-tech plant factories for urban food resilience. It finds that while vertical farms produce high yields, inhabitant involvement is minimal, offering no social advantages. Automated plant factories require few highly qualified personnel and are unlikely to contribute to urban social well-being in the future.

Nur Dinie Syahirah Sanusi, Fadhlina Che Ros, Siti Zulaikha Ngah Demon, Ismayadi Ismail, Imad Hamadneh · Journal of Advanced Research Design · Malaysia

This mini-review discusses the extensive use of AB mix nutrients in Malaysian urban farming, noting their role in high yields but also their contribution to significant environmental pollution when overused. Although a survey of local entrepreneurs showed most complied with guidelines for chili plants, intensive use of fertilizers leads to nutrient leaching into the soil, causing environmental pollution and affecting humans, livestock, and microbial life. The review emphasizes the need for controlled nutrient application to prevent soil degradation and groundwater contamination.

Waseem Ahmed Khattak · International Assulta of Research and Engagement (IARE) · Pakistan

"Go Green communities" in Pakistan were studied as grassroots movements promoting environmental awareness and sustainable practices. Using a Participatory Action Research (PAR) approach, activities included waste management, urban gardening, and policy advocacy. The initiative demonstrated increased community involvement in eco-friendly efforts, leading to tangible outcomes such as waste segregation systems and enhanced green spaces. However, challenges including financial limitations, resistance from industries, and restricted access to green technologies highlighted the need for stronger institutional support.