Research & reports

D. Z. Phillips, Heather I. Sullivan · ISLE Interdisciplinary Studies in Literature and Environment · United States

This collection of essays for ISLE assesses the material aspects of healthy economies, environments, and bodies, arguing that the traditional economic-ecological "health" dichotomy is insufficient. It finds that the determination of "healthy" is complex, as artificial environments can be benign, and even a flourishing community garden can have neglected produce going to waste. The essays explore how a large number of healthy human bodies can be detrimental to healthy environments.

Y. Niang, S. Niang, Saliou Niassy, Y Dieng, Mohamed Gaye, K. Diarra · International Journal of Biological and Chemical Sciences · Senegal

This study assessed the effect of wastewater on the agronomical performance and hygienic quality of tomato and lettuce in Senegal, comparing it to tap water, irrigation modes, and fertilizers. While tomato showed no pathogenic germs with wastewater, lettuce watered with wastewater via aspersion contained significantly more pathogenic germs than those watered in draining mode. Significant differences in yield and fruit size were observed between lettuce treated with tap water and wastewater.

Sebastian U. Ugbaje, John O. Agbenin · International Journal of Environmental Studies · Nigeria

A pot experiment in Zaria, northern Nigeria, evaluated the chemical forms and phytoavailability of Cr, Ni, and Pb in savannah soil amended with two urban wastes and planted with sorghum. While urban waste application increased total metal concentrations in the soil, only Pb uptake by sorghum increased, with no corresponding increases for Cr and Ni. A single application of urban wastes significantly increased Pb uptake by sorghum, raising concerns about the long-term consequences of such applications in urban and peri-urban agriculture, especially regarding children's exposure to Pb.

Vide Adedayo · · Nigeria

A study of poultry waste management and utilization techniques in urban vegetable farms in metropolitan Lagos revealed that poultry waste is poorly collected, packaged, and transported. Proper knowledge on treatment is lacking due to insufficient skill, space, time, and capital. Furthermore, a significant difference was found between poultry waste utilization, crop yield, and revenue in the study area.

Mirelys Rodríguez Alfaro, Olegário Muñiz Ugarte, Bernardo Calero Martín, A. Álvarez, Francisco Martínez Rodríguez, Teudys Limeres Jiménez, Mercedes Orphee Montoya, Adriana M. de Aguilar Accioly · DOAJ (DOAJ: Directory of Open Access Journals) · Cuba

This study evaluated the heavy metal content of Cadmium, Lead, and Nickel in organic fertilizers (composts from urban solid waste) and substrates, and their effect on vegetables grown in organoponics in Havana and Guantánamo, Cuba. Composts obtained from unsorted urban solid waste and the substrates prepared from them were found to contain heavy metals, especially Cadmium and Lead, above maximum permissible limits. It was concluded that these products should not be used for food production, as these metals translocate to the edible parts of the cultivated vegetables.

Chinedu Agbakoba, Funmilayo Olayiwala · Zenodo (CERN European Organization for Nuclear Research) · Nigeria

A paper framed as addressing a research gap on eco-friendly pesticide use strategies among urban farmers in Lagos State, Nigeria, health impacts, and environmental protection (2012) states that it conducted a structured literature review with thematic synthesis of key findings. However, the abstract's actual content is limited to generic mathematical-formalism language — establishing "bounded error under perturbation," a "convergent estimation process under stated assumptions," a "stable link between the proposed metric and observed outcomes," and an empirical specification described as a linear regression form (Y expressed as a linear function of X plus an error term) — and does not report specific data or results on actual pesticide practices, measured health impacts, or environmental protection outcomes among Lagos urban farmers. It closes by calling on stakeholders to prioritize inclusive, locally grounded strategies and improve data transparency.

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.

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.

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.

幸治 江口 · Institutional Repositories DataBase (IRDB) · Japan

The Santome Area in Saitama Prefecture has practiced circular urban agriculture utilizing plain woods for 300 years, but urbanization, particularly in Kawagoe City and Tokorozawa City, is causing a significant decline in farmland and plain woods. While the Ministry of Agriculture, Forestry and Fisheries and Saitama Prefecture promote urban agriculture and plain wood preservation, the plain-wood-utilizing circular urban agriculture in Santome Area faces specific problems. This paper identifies land systems, including taxation, as a central issue among these problems and examines the possibility of integrated preservation for farmland and plain woods.

Hyuck-Soo Kim, Young‐Nam Kim, Jin‐Won Kim, Kye-Hoon Kim · 한국토양비료학회지 · South Korea (Seoul)

This study investigated the properties and total and phytoavailable contents of heavy metals (Cd, Pb, Cu, Zn) in 21 urban agricultural soils in Seoul, South Korea. The total heavy metal concentrations in the examined urban agricultural soils were found to be lower than the warning levels for area 1 according to the Soil Environmental Conservation Act of Korea. Phytoavailable-Cu, -Pb, and -Zn concentrations were also reported as 0.02-0.28, N.D-0.09, and 0.01-0.43 mg/kg, respectively.

Julian S. Yates, Jutta Gutberlet · Environment and Planning A Economy and Space · Brazil (Diadema)

This paper analyzes food waste flows in Diadema, Brazil, through an urban political ecology lens, focusing on integrated organic waste management for composting and urban food production. While presented as a means for positive socioecological change, the process is characterized by conflict and potential exploitation. Broader structural conditions also constrain the system's ability to offer an alternative to existing waste-management models.

S. A. Materechera · African Journal of Agricultural Research · Africa

A study of soil salinity in irrigated fields used for urban agriculture in a semi-arid region of South Africa. It compares sodium levels (19.3 vs. 9.8), pH (7.13 vs. 6.3) and electrical conductivity ECe (22.1 vs. 7.9 dS/m) between topsoil and subsoil layers, finding that calcium, magnesium and potassium (unlike sodium) were higher in the top than the subsoil layer, while pH and ECe did not differ significantly by depth overall. By irrigation method, basin irrigation produced the highest accumulation of calcium, magnesium, potassium and sodium, followed by drip and then sprinkler irrigation, with the same ranking (basin > drip > sprinkler > control) for pH and ECe; sprinkler irrigation was the only method showing higher pH and ECe at 10-20 cm depth than at 0-10 cm. The study concludes that irrigation is increasing soil salinity and points to the need for sound irrigation water management, particularly appropriate irrigation scheduling.

Saad El‐Din Hassan, Eva Boon, Marc St‐Arnaud, Mohamed Hijri · Molecular Ecology · Canada

A study assessing indigenous arbuscular mycorrhizal fungi (AMF) community structure in roots and soil of Plantago major (plantain) growing on trace-metal (TM)-contaminated versus uncontaminated sites, selected based on a survey of TM concentrations (As, Cd, Cu, Pb, Sn, Zn) in community garden soils in Montreal, Canada. AMF community structure was analyzed using PCR-DGGE, cloning and sequencing, and direct sequencing. Native AMF diversity, measured by the number of AMF ribotypes, was decreased in TM-polluted soils and plant roots compared with unpolluted sites, and community structure was altered by TM contamination. Various Glomus species along with Scutellospora aurigloba and S. calospora were the most abundant ribotypes in unpolluted soil, while G. etunicatum, G. irregulare/G. intraradices and G. viscosum occurred in both polluted and unpolluted soils, and G. mosseae together with unidentified Glomus ribotypes (B9, B13) dominated in TM-polluted sites. The predominance of G. mosseae at metal-polluted sites is interpreted as suggesting tolerance to TM stress and potential use for phytoremediation.

Zhou Pei · · China (Shanghai)

A study conducted in Orchard Village, Nanhui District, Shanghai, from July to September 2009, investigated the effects of phosphorus non-point source pollution on groundwater in an urban agricultural region. Total phosphorus concentrations averaged 1.31 mg/L and phosphate concentrations averaged 0.42 mg/L, with phosphate significantly exceeding the V class surface water standard (0.4 mg/L), rendering the water unsuitable for drinking. Phosphorus non-point source transport was linked to land-use types, with phosphorus content near orchards changing with increased rainfall, and farmland phosphorus loss accelerating with runoff, fertilization, and water leach.

Mamadou Ndiaye, H.‐R. Pfeifer, S. Niang, Y Dieng, Mauro Tonolla, Raffaele Peduzzi · VertigO · Senegal (Dakar)

In Dakar's urban agriculture, untreated wastewater is used for irrigation due to shallow groundwater salinization. A study conducted at Pikine and Patte d'Oie sites evaluated the chemical and microbiological quality of irrigation water. Findings showed that total nitrogen in irrigation water exceeded WHO guideline values, Salmonella spp. was isolated from 35% of irrigation water, and a wastewater sample tested positive for Vibrio cholerae. This research indicates that irrigation with polluted water and the use of organic fertilizers can degrade groundwater quality and pose health risks.

Zhou Pei · · China (Shanghai)

A study from July to September 2009 in an orchard village, Nanhui District, Shanghai, investigated the characteristics of non-point source nitrogen pollution in groundwater. Total nitrogen and its three forms (NO3-N, NH4-N, NO2-N) were monitored, revealing NO3-N as the main form (average 1.43-13.71 mg/L). Nitrogen pollution in groundwater depended on land use, with NH4-N pollution most serious under residential areas (average 0.074-0.457 mg/L). Total nitrogen pollution near the river and orchard (average 33.67-62.57 mg/L and 33.05-65.04 mg/L) was more severe than under residential areas.

Hygin Faust Kakai, Alban Gilles Kakai, Armelle Grey Tohouegnon · VertigO · Benin (Cotonou)

This study in Benin examined urban agriculture and waste valorization in Cotonou, Abomey, and Abomey-Calavi. In Cotonou, overexploitation of sandy, organic-poor soil in market gardening led to soil impoverishment, forcing gardeners to use chemical fertilizers with negative environmental impacts. However, some market gardeners adopted compost use, transitioning to organized organic urban agriculture after a waste management project supported waste valorization. This dynamic was not observed in Abomey, where urban agriculture is practiced in family spaces and public areas, unlike Cotonou's developed sites. Abomey-Calavi, despite rapid demographic growth, was almost devoid of urban agriculture practices.

Xiaona Li · Nongye huanjing kexue xuebao · China

A study measuring dioxin-like compound (PCDD/Fs) concentrations in 23 surface soil samples collected from different areas of Baiyin City, China, using HRGC/HRMS (high-resolution gas chromatography/high-resolution mass spectrometry). The concentration range of 2,3,7,8-PCDD/Fs was 0.42-8.56 pg I-TEQ/g, averaging 2.28 pg I-TEQ/g. By land-use type, concentrations averaged 3.37 pg I-TEQ/g in industrial areas, 1.31 in urban areas, 1.01 in agricultural areas, and 0.85 in background areas, following the order industrial > urban > agricultural > background. Higher-chlorinated isomers were the dominant contributors to total toxic equivalency (TEQ) in most samples.

O. Muñiz, M. Ternero, Álvarez Montero, F. Martínez, T. Limeres, O. Jouber, M. Orphee, Julia Vidan Estevez, B. Calero, F. A. de Alcantara, Adriana María de Aguiar Accioly · Portuguese National Funding Agency for Science, Research and Technology (RCAAP Project by FCT) · Global

This paper situates its topic within the urban agriculture movement, which it describes as having successfully enabled low-input food production in cities, noting that organoponicos — plots focused on producing leafy vegetables and condiment crops in organic substrates — have driven up demand for organic material sources. The title indicates the study addresses the effect of using heavy-metal-contaminated compost on vegetable production, but the available abstract provides only this background context, with no results on contamination or crop impact stated.

Emma Schroeder, Julie Schneider · · United States (Eagle Heights)

Julie Schneider's 2009 interview discusses her five years at the Eagle Heights Community Garden. She described vegetables grown, organic gardening, rules and restrictions, and tensions with the university, as well as changes in the community gardens since the early 1990s. This interview was conducted for a Master's thesis on the Eagle Heights Community Gardens.

Rodrigue V.C. Diogo, Andreas Buerkert, Eva Schlecht · Nutrient Cycling in Agroecosystems · Niger (Niamey)

This 24-month study investigated nutrient efficiency and food safety in urban and peri-urban agriculture in Niamey, Niger. Nutrient inputs and offtakes were quantified for 10 vegetable gardens and 9 millet fields, and contamination of irrigation water and selected vegetables with fecal pathogens and heavy metals was determined. Above-threshold levels of Salmonella spp. and Escherichia coli were detected in lettuce irrigated with river water and fertilized with animal manure, and in lettuce irrigated with wastewater, indicating food safety concerns.

Crispen Dirwai, P.M. Makonese, N. Mboto · Figshare · Zimbabwe (Harare)

This study investigated how urban poor (Mabvuku-Tafara) and urban rich (Mabelreign, Marlborough, Westgate) communities in Harare, Zimbabwe, addressed the food crisis between 2005 and 2008. Using a mainly qualitative methodology to compare urban agricultural activities, findings showed that the urban poor engaged in seasonal, often inorganic, less paying off-yard farming, exposed to nature's vagaries. In contrast, the urban rich practiced on-plot perennial, often organic, researched (including soil testing) farming with greenhouses, which yielded better returns.

Andreas Buerkert, Eva Schlecht, Martina Předotová, Rodrigue V.C. Diogo, Katja Kehlenbeck, Jens Gebauer · eScholarship (California Digital Library) · Sub-Saharan Africa

This study analyzed urban and peri-urban agriculture (UPA) systems in major Sub-Saharan African cities, measuring carbon, nitrogen, phosphorus, and potassium fluxes and conducting biodiversity studies. In Niamey, low-input gardens showed annual gaseous carbon emissions of 20-25 t ha-1, predominantly CO2, and high-input gardens irrigated with wastewater had annual CO2-C emissions of 27 t ha-1, with N2O as a major nitrogen loss contributor. Animal manure stored in the open was subject to large carbon and nitrogen losses, indicating environmental tradeoffs. However, UPA gardens in Niamey maintained a large variety of fruit and vegetable species, with richness increasing with garden and household size and commercialization.