Research & reports

Evaristo Mwaba Kapungwe · Open Journal of Metal · Africa

Water, soil, and crop samples were analyzed by atomic absorption spectrometry for lead, copper, cobalt, nickel, and chromium at two peri-urban wastewater-irrigation farming sites in Zambia: New Farm Extension in Mufulira Town, Copperbelt Province, and Chilumba Gardens in Kafue Town, Lusaka Province. Heavy metal levels in wastewater, soil, and food crops exceeded acceptable limits at both sites, confirming contamination and a potential human health risk from consuming the crops grown there.

QI Airon · · China

A study of Xi'an, China, built indicators for urbanization and urban agriculture development and applied principal component analysis and correlation analysis to examine their interaction mechanism and quantitative coupling relationship. Urbanization was found to promote urban agriculture's commercialization and scale through market effects and information diffusion, but rapid urbanization's rising population and industrial land use also strained land and water resources and degraded soil and the urban ecological environment, constraining urban agricultural development.

G. N. Egwu, John O. Agbenin · Archives of Agronomy and Soil Science · Nigeria

A study in northern Nigeria assessed cadmium, lead, and zinc contamination in soils and leaf vegetables (amaranthus, lettuce) irrigated with untreated wastewater. Total cadmium and zinc concentrations in soils exceeded safe limits, and lead and cadmium in edible portions of amaranthus and lettuce exceeded safe limits for human consumption by 7–17 times. The permissible limit for lead established for agricultural lands may not be suitable to ensure produce safety in urban and peri-urban agriculture in Kano.

David Tijero · Aldiri: arkitektura eta abar · Spain (Bilbao)

This article criticizes the municipal administration's attitude towards informal allotments on the outskirts of Bilbao. It analyzes the consequences of green space reclamation plans executed in recent years and advocates for policies promoting both formal and informal urban agriculture.

Sylvestre Dasylva · Journal of environmental science & engineering · Senegal (Dakar)

This paper discusses rainwater management in the "niayes" zone of Dakar, Senegal. This area is characterized by agricultural depressions with typically high groundwater levels, but a recent drop has turned some into runoff-gathering sites, used for urban agriculture among other services. However, two acute problems are observed: hydrological drying due to insufficient rainwater refill and urbanization of these bottom-lands. Furthermore, decreasing pluviometry exacerbates nuisances like floods and malaria.

Coline Perrin · International Planning Studies · France, Italy

Case studies in Provence and Tuscany indicate that planning prescriptions and land-market control are insufficient for protecting farmland on the urban fringe. Farmland is not effectively protected if regulatory approaches are not integrated into a global strategy for agriculture and food based on community involvement. Farmland protection policies are more effective when combining top-down policies with bottom-up initiatives and recognizing the multifunctional character of urban agriculture.

Ana Carolina Paiva Rodrigues · VII CONNEPI - Congresso Norte Nordeste de Pesquisa e Inovação · Brazil (Natal)

In the Gramorezinho region of Natal-RN, Brazil, an exploratory study analyzed the socioeconomic and productive characteristics of urban and peri-urban agriculture. The methodology involved examining farmers' socioeconomic profiles, adopted production systems, and commercialization methods for key vegetable species. The study concluded that the legitimization of urban and peri-urban agriculture in Natal-RN is flawed, not only concerning municipal legislation but also regarding the guarantee of support and technical assistance for agricultural activities.

Evaristo Mwaba Kapungwe · Indonesian Journal of Biotechnology (Universitas Gadjah Mada) · Zambia

This study investigated farming practices related to heavy metal contaminated wastewater irrigated farming in two peri-urban areas of Zambia: New Farm in Mufulira and Chilumba Gardens in Kafue. Data was collected by observing crop cultivation activities at field plots along transects in stratified land zones. The results revealed that farming practices were characterized by traditional land management and multiple cropping systems, influenced by agro-ecological factors and the availability of heavy metal contaminated wastewater, which has the potential to contaminate soils and crops.

Nancy Karanja, Mary Njenga, G.K. Mutua, Carl Johan Lagerkvist, E. Kutto, JJ Okello · Journal of Agriculture Food Systems and Community Development · Kenya (Nairobi)

A study in three peri-urban sites in Nairobi, Kenya, assessed heavy metal, nitrate, and pesticide residue levels in wastewater-irrigated kale. Elevated levels of boron, cobalt, chromium, copper, lead, zinc, and nickel were found in vegetables at two sites, with high soil loadings of nickel, arsenic, lead, chromium, copper, and zinc attributed to chicken manure. Pesticide residues of diazinon, cypermethrin, biternol, and profenofos exceeded permissible limits in kale at one site, suggesting consumers may ingest significant amounts of contaminants.

Catherine Rwamba Githuku · Abstracts of postgraduate thesis · Kenya (Nairobi)

This study investigated soil and crop pollution levels resulting from untreated wastewater reuse for irrigation in Kibera and Mailisaba wastewater irrigation farms in Nairobi, Kenya. Analysis of irrigation water, soil, and crop samples (maize, kales, black nightshade, arrowroots) revealed that the Electrical Conductivity (EC) of irrigation water at Mailisaba exceeded recommended levels. Farmers reported adverse effects on crops due to wastewater quality, and despite awareness of health risks, many farmers confessed to not using protective clothing.

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.

Luc Hippolyte Dossa, Andreas Buerkert, Eva Schlecht · Human Ecology · Sub-Saharan Africa

A study surveyed 700 randomly selected households across Kano (Nigeria), Bobo Dioulasso (Burkina Faso), and Sikasso (Mali) to explore the relationship between household socioeconomic status (SES) and participation in urban and peri-urban agriculture (UPA). The results showed no significant differences in UPA participation rates across socioeconomic groups. Instead, UPA participation was significantly and positively related to household size.

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.

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.

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.

Héctor Ávila-Sánchez · Norois · Mexico

This paper discusses socio-territorial changes in peri-urban food production spaces in Central Mexico, focusing on the impacts of urbanization on old rural areas. It highlights that peri-urban poor populations often face marginalization, degradation of their agricultural activities, and conflict over space with other social groups. The development of peri-urban agriculture has led to significant transformations in land use, production structures, and social and cultural aspects.

知弘 岡田, 大介 小山 · Institutional Repositories DataBase (IRDB) · Japan

This paper is part of a special issue on the "Possibility and problem of 'coexistence of agriculture and housing' in suburban agricultural region of big city," presenting an overview of the urbanization process and contemporary challenges of town planning in the Kuga-Hatsukashi area of Fushimi Ward, Kyoto City.

Haruna Haruna · · Africa

A study of soils irrigated with sewage water on Fadama floodplain land in northern Nigeria used sequential extraction to determine the mobility and availability of cadmium, copper, nickel, lead and zinc. The residual fraction held the largest pool of all five metals, but 2.7-70.2% was present in the potentially available, non-residual fraction. Contamination by cadmium and nickel was less severe than by lead, copper and zinc, and mobility/bioavailability ranked Pb > Zn > Cu > Ni > Cd.

Geoffrey Ross Owens · Africa · Tanzania (Dar es Salaam)

This article, using ethnographic and historical approaches, examines unplanned peri-urban settlements on Dar es Salaam's northern and western fringe, Tanzania, between 1975 and 2000. These districts were established by educated urban professionals who used urban farming as an economic diversification strategy. The study found that these settlements contributed to the reproduction of socio-economic inequality, attracting additional economically influential urban in-migrants after 1991.

Senthot Sudirman, Irham Irham, Slamet Hartono, Azwar Maas · · Indonesia (Yogyakarta)

This study analyzed agricultural land use changes in peri-urban Yogyakarta from 1996-2007, covering 922.17 ha in Sleman, 1,888.60 ha in Bantul, and 1,082.79 ha across 47 villages. Factors like agricultural production exchange value, irrigated land, built area percentage, population density, education, and land price significantly influenced land change rates, which negatively correlated with distance from the city. However, agricultural land percentage to village area, land tax, and dummy variables for Bantul and Kulon Progo did not significantly influence these rates, and the changes negatively impacted regional food loss, availability, and farming sustainability prospects.

Kohei Makita, Eric M. Fèvre, Charles Waiswa, Mark Bronsvoort, Mark C. Eisler, Susan C. Welburn · Land Use Policy · Uganda

This paper describes a spatial representation of the peri-urban interface (PUI) of Kampala, Uganda, and identifies socio-economic factors related to peri-urbanicity using rapid rural mapping. It notes that urban and peri-urban agriculture (UPA) in rapidly expanding cities carries public health risks, such as zoonotic disease transmission. The study provides a methodology for describing the PUI in developing countries.

Alec Thornton, Etienne Nel, Godfrey Hampwaye · Development Southern Africa · Zambia

A review of urban agriculture in Zambia's four largest cities revealed that despite attempts by the Kaunda government in the 1960s–1970s to create supportive policies, there is currently a near absence of institutional support, constraining farmers' activities. A survey of 400 farmers confirmed the value of urban agriculture as a survival strategy but also highlighted the lack of necessary support measures.

Kwasi Appeaning Addo · Remote Sensing · Ghana (Accra)

This paper discusses the need for sustainable management of urban and peri-urban agriculture in Accra, Ghana. A lack of reliable data on the extent of urban/peri-urban areas used for farming has hindered the development of sustainable policies to manage urban farming in Accra. Ground-based survey methods are problematic and prohibitively expensive, making accurate assessment of urban farming's future role difficult.

FU Li-hua · 自然资源学报 · China (Shanghai)

A study of Shanghai, China, building an evaluation index system reflecting the characteristics of sustainable urban agricultural development, using a combination of the analytic hierarchy process (AHP) and the information entropy method to determine index weights, and applying it to time-series data from 1993 onward to produce a quantitative, comprehensive appraisal. The results comprise three findings. First, the population subsystem progressively became a main obstructive factor for sustainable urban agricultural development, the economic subsystem gradually became a main contributing factor, and the social subsystem grew more important in raising development capability, while cultivated land resources became increasingly scarce and continued to decrease, constraining improvement, and the heavy burden of agricultural production's self-pollution had a negative effect on the overall upgrade of development capability. Second, the resource (R-D) composite index was not high and declined significantly, averaging 1.9090 over 1993-2006 and falling 6.00% per year from 2.5336 in 1993 to 0.5541 in 2006, indicating growing resource pressure; the environmental (E-D) composite index was smaller and changed little, remaining around 1.0000 in most years, with environmental pressure staying high but stable. Third, after earlier wave-like fluctuations, the overall composite evaluation index entered a sustained, steady climb, with a significant increasing trend in development capability.