Research & reports

Sally Brown, Ingrid Clausen, Mark A. Chappell, Kirk G. Scheckel, M. Newville, Ganga M. Hettiarachchi · Journal of Environmental Quality · Global

Against a background in which the safety of urban farming has been questioned because of possible contamination in urban soils, this study tested whether high-iron biosolids-based composts could reduce the bioaccessibility of soil lead (Pb) and arsenic (As), using two laboratory incubations and a field trial. Pb and As bioaccessibility were assessed with an in vitro assay, and changes in Pb, As, and Fe speciation were analyzed on select samples using micro-X-ray fluorescence mapping and micro-XANES. A compost with iron added to wastewater-treatment residuals (Fe WTR compost), applied to soil at 100 g/kg, decreased Pb bioaccessibility in both laboratory incubations, though results for As were mixed. In contrast, the composts tested in the field trial (with iron added as Fe powder or FeCl) did not reduce bioaccessible Pb and showed only limited reductions in bioaccessible As; these same composts also had no effect on Pb bioaccessibility in the second laboratory incubation. The study concludes that high-iron biosolids compost is effective at reducing Pb accessibility only for certain types of iron-rich materials.

André Viljoen, Katrin Bohn · Architectural Design · Global

This piece by André Viljoen and Katrin Bohn of Bohn&Viljoen Architects juxtaposes the organopónicos, or market gardens, of Cuba — which proliferated after the US trade blockade of the 1990s and the resulting fuel shortages — with more recent food-production experiments in North American cities that draw on the Cuban example. The authors argue that in urban agriculture there is a direct connection between scarcity and abundance, with the threat of food shortages repeatedly acting as an effective trigger for food-growing enterprises, and that produce can be grown even with few or limited resources.

R. Plant, Jeremy Walker, Scott Rayburg, J Gothe, Teresa Leung · Australian Geographer · Australia

A study of the Hawkesbury-Nepean River in Sydney, Australia, examines the effects of pesticide use by the small-scale horticulturalists supplying the city's fresh vegetable markets on aquatic biodiversity. Through interviews with actors across the institutions responsible for agriculture, water quality, and environmental protection, it assesses the effectiveness of pesticide governance in the Greater Sydney Basin. It finds that pesticide pollution is rarely measured or monitored and is not a priority for any particular agency, meaning the pollution remains effectively uncontrolled. The study concludes that although public health, the long-term viability of local farming, and the ecological health of the river are compatible goals, they currently exist under a system of "organised irresponsibility."

Leigh Whittinghill, D. Bradley Rowe · Renewable Agriculture and Food Systems · Global

Urban agriculture faces limitations including competition for space, lack of formalized land use rights, and health hazards from food contamination. Green roof technology is proposed as a method to alleviate these issues, potentially reducing the use of contaminated land and water at ground level. However, for large-scale implementation, installation costs must be reduced, roof weight limitations assessed, and appropriate management practices developed.

Simon Mariwah, Jan-Olof Drangert · Waste Management & Research The Journal for a Sustainable Circular Economy · Ghana

A study in a peri-urban agricultural community in Ghana explored attitudes towards sanitized human excreta as fertilizer, collecting data from 154 households. It found a general negative attitude towards fresh excreta and its handling. While residents accepted excreta could be used as fertilizer, they were unwilling to use it on their own crops or consume such fertilized crops.

Gerald Forkuor, Olufunke Cofie · International Journal of Remote Sensing · Sierra Leone (Freetown)

A land-use and land-cover (LULC) change mapping exercise in Freetown, Sierra Leone, used multi-temporal Landsat data from 1974, 1986, and 2000 to map nine LULC classes. Built-up areas increased by at least 140% between 1974 and 2000, and 882 ha (27%) of agricultural lands in 1986 were converted to residential purposes by 2000. These conversions indicate a strong link between urbanization, agriculture, and deforestation, negatively impacting agricultural land availability.

Zikrullah Safi, Martina Předotová, Eva Schlecht, Andreas Buerkert · Journal of Plant Nutrition and Soil Science · Afghanistan (Kabul)

A two-year study in Kabul, Afghanistan, measured horizontal flows of C, N, P, and K, and leaching losses of N and P in 21 vegetable gardens, 18 cereal fields, and vineyards. The findings suggest that soils in extensive cereal fields are at risk of N and K depletion, vegetable gardens face K depletion, and vineyards may be oversupplied with nutrients, potentially contributing to groundwater contamination. These results merit verification.

Christophe Antonio‐Nkondjio, Billy Tene‐Fossog, Cyrille Ndo, Benjamin Menze Djantio, Serge Zebaze Togouet, Parfait Awono‐Ambene, Carlo Costantini, Charles S. Wondji, Hilary Ranson · Malaria Journal · Cameroon

This study assessed the influence of urban pollution and agriculture on malaria vector distribution and insecticide susceptibility in Douala and Yaoundé, Cameroon, from October 2009 to December 2010. Researchers sampled 1,546 anopheline larval breeding sites and analyzed water parameters. Findings showed mosquitoes from cultivated urban areas exhibited the highest insecticide resistance levels, with urban agriculture, rather than pollution, suggested as the major factor driving resistance.

Hong‐Yi Chen · Nongye xiandaihua yanjiu · Global

This article discusses the vulnerability of urban agriculture, identifying its performance in human resources, land resources, capital flows, and the ecological environment. The primary reason for this vulnerability is the unreasonable flow of human, financial, and material production factors, driven by opportunity costs, amidst rapid urbanization. Strategies for healthy development include enhancing protection awareness, promoting orderly rural labor flow, improving investment, and strengthening land resource protection.

Rachel Carey, Fanny Krumholz, Kena Duignan, Kathy McConell, Jessica L. Browne, Catherine Burns, Mark Lawrence · Journal of Agriculture Food Systems and Community Development · Australia (Victoria)

This policy analysis examined fruit and vegetable production in peri-urban areas of Melbourne, Victoria, Australia. It highlights that environmental pressures, the loss and cost of peri-urban agricultural land, and a cost-price squeeze due to rising input costs and low farm-gate prices combine to threaten the viability of the Victorian fruit and vegetable industries. These pressures suggest that the availability and affordability of fruit and vegetable supplies cannot be taken for granted.

L Ndiaye M, Y Dieng, S. Niang, Rak H, Mauro Tonolla, Raffaele Peduzzi · African Journal of Microbiology Research · Senegal (Dakar)

A survey in Dakar, Senegal, assessed the effect of irrigation water quality on Salmonella spp. incidence in lettuce. Microbiological analysis revealed that 35% of irrigation water was contaminated by Salmonella spp., with no significant difference between groundwater and wastewater. Lettuce from Dalifort and Grand-Yoff markets showed significantly higher contamination rates than those from Sham and Zinc markets. The study concluded that irrigation water and manure are potential sources of contamination, and lettuce may serve as a vector for pathogen transmission to consumers.

Marie-Christine Zélem, Zelem, Marie-Christine · AgEcon Search (University of Minnesota, USA) · Senegal (Dakar)

This study identifies numerous constraints hindering the widespread adoption of organic waste utilization in agriculture in the peri-urban area of Dakar, Senegal. These constraints include the nature, availability, and accessibility of organic waste, poorly controlled urbanization, effects of seasonal variation, resistance to changes, and medical risks. The project, which combines agriculture with city waste management, faces these challenges.

Inge Wagemakers, Oracle Makangu Diki · Palgrave Macmillan UK eBooks · Congo (Kinshasa)

In rapidly growing African cities, particularly Kinshasa, urban agriculture is crucial for food provision, yet land available for agriculture decreases as cities expand. This study points out that in Kinshasa, population growth and a lack of empty land are pushing agriculture towards the city's periphery, threatening urban agricultural space. This situation highlights a conflict between the need to produce food and the need for living space.

José Luis Galdeano Tostado · Creatividad y sociedad: revista de la Asociación para la Creatividad · Global

This paper observes an increasing awareness of environmental issues and neighborhood action in city centers, with concepts like urban gardens and self-managed spaces becoming more familiar. It suggests that vacant lands and unused building sites in cities offer significant potential for citizens' creative initiatives. The abstract does not present any specific findings on governance challenges or critical interventions.

John James Okiror, Biryabaho Matsiko, Joseph Oonyu · Journal of Agricultural Education · Uganda

This study, conducted in eight primary schools in Uganda, compared the learning achievement of pupils taught using supervised home gardens and those taught using school gardens. Data were collected over four school terms using questionnaires, focus group discussions, interviews, observations, and a posttest examination, and analyzed with a t-test. Findings showed no significant difference in knowledge achievement between the two groups of pupils.

Ari Jokinen, Ville Viljanen, Krista Willman · Alue ja Ympäristö · Finland (Tampere)

This article analyzes the social and ecological significance of the Pispala allotment area in Tampere, Finland, where nearly 300 plots are used for urban farming, despite city plans for building purposes. A mixed-method analysis, using field observation, planning documents, biological surveys, and questionnaires, found that farming practices make the place visible, foster social interaction, and link the site ecologically to rare plant species. However, these crucial features of urban diversity are frequently disregarded by local administrative bodies in planning.

Dieudonné E. Musibono, E.M. Biey, M. Kisangala, Camille Ipey Nsimanda, B.A. Munzundu, V. Kekolemba, J.J Palus · VertigO · Democratic Republic of Congo (Kinshasa)

Urban agriculture in Kinshasa, Democratic Republic of Congo, serves as a palliative solution for social survival constraints such as a lack of remunerative salaries and sustainable jobs. However, poorly supervised urban farmers cultivate along busy roads, exposing vegetables to various contaminations, including lead. This practice highlights issues with site selection and supervision.

Hillary Anne Doerfler · D-Scholarship@Pitt (University of Pittsburgh) · Global

A literature review examined the use of school garden programs for health promotion among elementary school youth. The review found that school gardens successfully improved academic achievement, increased fruit and vegetable consumption, and enhanced social skills. However, significant barriers to implementation were identified, particularly in low socioeconomic status schools, including a lack of funding, insufficient gardening knowledge among teachers, and limited community and parent involvement.

I Kibona, SL Mkoma, IC Mjemah · International Journal of Biological and Chemical Sciences · Tanzania (Morogoro)

Groundwater samples were collected from 20 wells in six wards of Morogoro municipality, Tanzania, during March-April 2010, and nitrate concentrations were measured. Nitrate levels ranged from 1.4 mg/L to 32.5 mg/L, with an average of 7.76 mg/L. These concentrations were below the upper limits set by the Tanzania Bureau of Standards and the World Health Organization.

Masao Makiyama, Mami Inoue · JOURNAL OF RURAL PLANNING ASSOCIATION · Global

This study examined kleingartens (stay-type allotment gardens) established by private organizations, finding an increasing number of such gardens. Case studies revealed that privately established kleingartens tend to have higher use fees compared to government-established ones. Furthermore, problems identified include the reduction of administrative and maintenance expenses, location conditions, and the succession of managers.

Nyumbaiza Tambwe, Michael Rudolph, Ran Greenstein · Africa · Democratic Republic of Congo (Lubumbashi)

A study was conducted in Lubumbashi, Democratic Republic of Congo, from November 2004 to March 2005, on 100 farming households that adopted urban agriculture as an alternative livelihood after the collapse of a mining company. Data collected through semi-structured interviews, in-depth questions, and observation revealed that despite practicing urban agriculture, the living conditions of 75% of households declined, and 20% stabilized their living conditions but could not completely alleviate poverty. Only 5% of farmers achieved food security.

Sinan Koont · University Press of Florida eBooks · Cuba

An assessment of Cuban urban agriculture's production and distribution outcomes finds that the most successful subprogram is fresh vegetable production, which has grown rapidly island-wide, while other subprograms remain active but less developed. Distribution occurs through thousands of points-of-sale, MALs, self-provisioning, and MAEs, with social consumption at workplaces, hospitals, and schools. Urban agriculture plays a significant role in improving Cuban diets but has not led to food sovereignty; other outcomes cited include employment generation, environmental benefits, and community building.

Luke M. Brander, Mark J. Koetse · Journal of Environmental Management 92(10): 2763-2773 · Global (meta-analysis)

Runs separate meta-analyses of the contingent-valuation and hedonic-pricing literatures to examine which physical, socio-economic and study-design characteristics drive the value of urban open space. Finds a positive, significant relationship between population density and open-space value, and that urban parks are valued more highly than forest, farmland or undeveloped land - but flags that methodological differences across studies have a large effect on estimates and that regional preference differences may limit how transferable any single value estimate is.

Barbara Matthys, Benjamin G. Koudou, Eliézer K. N’Goran, Penelope Vounatsou, Laura Gosoniu, Moussa Koné, G. Gissé, Jürg Utzinger · Annals of Tropical Medicine and Parasitology · Côte d'Ivoire (Abidjan)

Two surveys were conducted in market gardens of Abidjan, Côte d'Ivoire, during the rainy and dry seasons to identify mosquito breeding habitats. The study found that urban agriculture areas may lead to higher densities of mosquito breeding sites, with "agricultural trenches" between seedbeds being the most likely sites to be positive for Anopheles larvae and mosquito pupae.

Charles French, Mimi Larsen Becker, Bruce E. Lindsay · Journal of Agriculture Food Systems and Community Development · Cuba (Havana)

This study examined urban agriculture in Havana, Cuba, using secondary data and interviews with 11 urban gardeners. It found that while agrarian reforms after 1991 led to the growth of private urban gardens and cooperatives, Cuba's integration with the global economy and adoption of free-market principles have since forced dramatic adjustments in the urban agriculture sector. This shift presents challenges to the sector's original role in food security.