Research & reports

Martin Dyer, Richard M. Mills, Beatrice Conradie, Jenifer Piesse · Open University of Cape Town (University of Cape Town) · South Africa (Cape Town)

This paper investigates the efficiency relationships between inputs and outputs of urban micro-farms in two Cape Town townships, Nyanga and Khayelitsha. Data Envelopment Analysis (DEA) applied to 33 producers supplying a social enterprise box scheme revealed an average overall efficiency of 72.4%. Overall efficiency was negatively correlated with land holdings and the use of compost and seedlings, indicating efficiency losses with greater input quantities. Furthermore, it was not shown that mulching or operator experience increases profitability.

Achamyeleh Gashu Adam · · Ethiopia

A study assessed the process of built-up property formation in Ethiopia's peri-urban areas. Through analysis of survey results and a review of relevant literature, the study elucidated the processes of peri-urbanization and new property development. It demonstrated that both formal (legal) and informal methods are equally important in converting peri-urban agricultural lands into urban built-up non-agricultural properties. This process creates intense competition for land between agriculture and non-agriculture, leading to the emergence of new property rights and the dissolution of existing traditional rights.

M. G. Dahiru, Onaiwu Idahosa Enabulele · · Nigeria (Kano)

Microbiological and physicochemical parameters of urban wastewater from the Jakara Canal in Kano were analyzed to assess its potential for irrigation. Mean fecal coliform counts ranged from 64.43 ± 63.20 MPN 100/ml to 216.85 ± 350.16 MPN 100/ml, increasing along the canal. All physicochemical parameters were within FEPA and WHO/FAO acceptable limits, but conductivity needed monitoring to avoid salinity.

Nyasha Chaminuka, Peter Makaye · Global Journal of Human-Social Science · Africa

This paper analyzes urban agriculture in Mkoba, Gweru, as a survival strategy for residents facing food insecurity and poverty, despite opposition from city authorities. It argues that urban agriculture is a resilient practice that has become a significant feature of urban livelihoods, often increasing the burden on women. The paper suggests that city authorities are losing the contest over urban spaces and should reform legislation to accommodate urban agriculture.

West Africa, Olufunke Cofie · · West Africa

An examination of urban agriculture (UA) development in West Africa reveals that despite its known benefits for food supply and livelihoods, UA is not fully recognized as an important component of urban development. This is due to high land demand from other sectors and perceived health risks by authorities. Policy makers need to address issues to institutionalize UA and integrate it into urban development plans.

Vide Adedayo · Journal of Research in National Development · Nigeria (Lagos)

This study investigated poultry waste management in urban vegetable farms in Metropolitan Lagos from an ecosystem to human health perspective. Using a transdisciplinary approach, community participation, and socio-cultural, physiochemical, microbiological, and clinical information, the research revealed negative impacts and health problems associated with poultry waste management due to poor storage, composting, and packaging techniques. Consequently, adverse effects on users were identified.

Baltazar M.L. Namwata, Idris S. Kikula, Peter A. Kopoka · Journal of African studies · Africa

A study examined urban farmers' access to land, water and inputs for urban agriculture toward household food security, employment creation and income generation in Dodoma municipality, Tanzania. A cross-sectional survey of 300 urban farmers from both squatter and non-squatter settlements used structured questionnaires, focus group discussions, key informant interviews, observations and documentary review. The analysis found urban farmers constrained by land tenure insecurity, erratic water access, inadequate inputs for optimizing plot productivity, and ambivalent application of urban legislative frameworks, with no support given to enable urban farmers to access land, water and inputs. The apparent lack of political will necessary to promote such access is reflected in weak or absent policy frameworks, resulting in an enormous capacity deficit.

H.W. Kamwele, George Mark Onyango, George G. Wagah, Maria Nyström · Chalmers Publication Library (Chalmers University of Technology) · Kenya

This paper examines the legal and policy framework affecting urban agriculture development in Eldoret Municipality, Kenya, through a case study involving interviews with government officials and review of various acts and bylaws. It found that while national legislation allows for urban agriculture, there is no specific policy for it, and Eldoret Municipality tolerates the practice despite its illegality. The study concludes that the awareness of urban farming's importance has not translated into formal recognition in bylaws and ordinances.

Taibat Lawanson, Olabode Orelaja, Michael Simire · African Journal of Science Technology Innovation and Development · Nigeria (Lagos)

This case study investigated the effects of climate change on agricultural activities in the Igbe Farming Community, Lagos, Nigeria, by surveying 161 farmers. The study found that most migrant farmers leased plots annually or biennially and made marginal profits of $200 to $350 per farming cycle. Erratic weather patterns and aggressive urban growth were major challenges, leading 48% of respondents to engage in informal enterprises.

Joseph Agossou, Léonard Afouda, Julien Didier Adédémy, Alphonse Noudamadjo, Catherine N’da Tido, Emanliikpon Sylvain Ahohoui, Pierre G. Tovihoudji, Farouk Mazou, Benjami Fayomi, Simon Akpona, Sikiratou Adéothy-Koumakpaï, B Ayivi · Environnement Risques & Sante · Benin (Parakou)

This study analyzed the bacteriological and parasitic load in wastewater and market garden products from five major production sites in Parakou, Benin, where farmers use wastewater for irrigation. High concentrations of fecal coliforms, Escherichia coli, Salmonella enterica, Shigella spp., Entamoeba coli, Giardia intestinalis cysts, and helminth eggs were found in irrigation water, vegetables, and farmers' stools. The use of wastewater resulted in high contamination of vegetables, particularly cabbage, large lettuce, and carrot leaves, by fecal coliforms, Salmonella enterica, and Escherichia coli.

UM Dawaki, A. U. Dikko, SS Noma, U. Aliyu · Nigerian Journal of Basic and Applied Sciences · Nigeria

A study investigated the total, exchangeable, and soluble concentrations of heavy metals (Cu, Cr, Ni, Zn, Pb, Cd) in urban agricultural soils along three rivers (Challawa, Jakara, and Watari) in Kano, Nigeria. Cadmium concentrations at Jakara and Challawa exceeded maximum allowable concentrations in soils. Heavy metal concentrations were found to be significantly higher in areas irrigated with industrial and domestic sewage (Challawa and Jakara) compared to the control site (Watari).

Ekaete Francis Asuquo · · Nigeria (Calabar)

The impact of urban expansion on agricultural land in Calabar and its environs, Nigeria, was investigated. A survey of 150 questionnaires and comparative assessment revealed a decrease in agricultural land in the fringes as urban expansion persists and increases. Before 2013, more farmers owned larger plots, but much of this agricultural land has been converted to housing estates, roads, leisure resorts, and schools, indicating that urban expansion has negatively impacted agricultural land, reducing food productivity and leading to farmer unemployment.

A. N. Mutune, M. A. Makobe, Mary Abukutsa‐Onyango · African Journal of Environmental Science and Technology · Kenya (Nairobi)

This study analyzed heavy metal content in 10 common African leafy vegetables and their rhizosphere soils from 25 sites along Nairobi Rivers, Kenya. While soil metal concentrations were generally within WHO/FAO permissible levels, except for some cadmium instances, all metals except copper in vegetables exceeded recommended limits at a few sites. This indicates potential heavy metal absorption from industrial and domestic effluent.

H. C. Agada, E. A. Obienusi, Emma E. Ezenwaji · Journal of environment and earth science · Nigeria

This study evaluated urban forestry and housing patterns in Awka metropolis, Anambra State, Nigeria, over a ten-year period (2001-2010). Analysis of land use data using linear regression and correlation coefficients confirmed a significant correlation between housing patterns (urbanization) and the distribution of trees (forestry). The least square regression results indicated that the rate of forest displacement is a direct consequence of increasing structural development in the study area.

Suarau Odutola Oshunsanya, Tolafe Olayinka Adeniran · Agricultura tropica et subtropica · Nigeria (Ibadan)

A field experiment in Ibadan investigated the quality of irrigation water used for dry season vegetable cultivation along Ona-stream. Water samples from five isolated ponds and one locally dug well were analyzed for heavy metal status. Results showed high concentrations of Pb, Cr, and Co in soil from five farms (A-E) near the stream, and isolated pond water also contained Cr, Co, and Pb exceeding safe consumption thresholds. All vegetables irrigated with untreated isolated ponds contained Cd, Pb, and Ni concentrations above maximum permissible standards, posing potential risks to human health.

Achamyeleh Gashu Adam · African review of economics and finance · Ethiopia

In Ethiopia, all land is state-owned and granted to residents only as a holding right, with separate systems for rural and urban areas. Focusing on peri-urban agricultural land under growing pressure from urbanisation, this desk-review study analyzed existing survey research together with property-rights literature, theory, and current land-rights laws and policies. It found that new recipients of peri-urban land under the urban land-lease system obtain better and more extensive bundles of land rights than the indigenous, local peri-urban landholders who previously held that land.

Y. Saleh, Amul M. Badr, F. El Banna, A. Shahata · Science World Journal · Nigeria

Using a combination of remote sensing and GIS, this study assessed the rate of agricultural land-use change in the Kaduna metropolis, Nigeria, between 1980 and 2012, classifying and comparing four satellite images (Landsat MSS 1980, Landsat TM 1990, Landsat ETM+ 2005, and Nigeria Sat X 2012). The study found a significant reduction in agricultural land and continued disappearance of farmland over the period, which it links to loss of livelihoods, reduced food supply, and increased poverty. It states that this has raised concerns about the sustainability of urban and peri-urban agriculture (UPA) production in the study area, with small-scale farmers the most affected.

Ande O.T, Adetunji A. M, Akinpelu M. E, Senjobi B.A · Journals & Books Hosting (International Knowledge Sharing Platform) · Nigeria

Ibadan metropolis, Nigeria, home to about 6 million people, has raised growing concern over lowland soils in its periurban area, where much of the industrial waste transported by the River Ona is deposited; these soils are used for dry-season farming and contribute to food security. This study aimed to characterize periurban lowland soils around Ibadan and determine their vulnerability to industrial pollution, using a 50m x 50m grid with surface samples taken at 50m intervals, plus representative profile pits described using the USDA method, and particle-size and chemical analyses (phosphorus, nitrogen, exchangeable cations Ca/Mg/Na/K, manganese, and heavy metals including lead, copper, zinc, chromium, iron, and cadmium). Results showed the floodplain's surface soil was fertile, with high nitrogen (0.35 cmol/kg), phosphorus (51.25 cmol/kg), and potassium (0.61 cmol/kg), and phosphorus levels ranging from very high to toxic, between 28.99 and 87.70 ppm. Average heavy metal concentrations were lead 34.30 mg/kg, zinc 171.20 mg/kg, iron 83.97 mg/kg, copper 19.11 mg/kg, manganese 31.10 mg/kg, chromium 0.69 mg/kg, and cadmium 0.3 mg/kg. Predicted soil-to-plant heavy metal transfer coefficients (Pb 35-343; Cr 0.46-4.6; Zn 171-1712; Cu 19-191; Fe 83-840; Mn 31-281; Cd 0.1-10) indicated crops grown in the area could contain toxic levels of these metals; however, high yields and healthy plant condition observed in the field, together with farmer interviews, suggested that the high phosphorus level (28.99-87 ppm) may have inhibited uptake of some metals such as lead, zinc, and copper.

C.F.A. van Wesenbeeck, Valentijn Venus, M.A. Keyzer, B. Wesselman, D. Asare Kye · · Africa

This study examined two tomato production areas in Burkina Faso with potential for counter-seasonal production aimed at Ghanaian urban markets, identifying the main obstacles to developing a horticultural supply chain: the monopsony power of Ghanaian traders and insufficient road quality causing high mechanical-damage losses in transport. Using a spatial-temporal simulation model to assess transport effects on tomato quality, the study found refrigerated transport is not a necessary condition for successful trade, since climate conditions alone do not severely harm quality, and concluded that regional diversification of exports offers Burkina Faso producers the best opportunities for improving their position in the chain, given the persistent trader monopsony and infrastructure constraints.

N E Etim, J J Dukiya · International Journal of Advanced Remote Sensing and GIS · Nigeria (Abuja)

A study in the Kuje area council of Abuja, Nigeria, used questionnaires and multi-temporal satellite images from 1975–2010 to assess urban encroachment on agricultural lands. It found that urban encroachment into agricultural lands is occurring at an alarming rate of 15.7 km² annually, resulting in a total loss of 509 km² of agricultural land to urbanization over 35 years.

AN Asadu, EM Igbokwe, JM Chah, IA Enwelu · Journal of Agricultural Extension · Nigeria (Enugu)

This study investigated farmers' perceptions of health and environmental hazards from urban livestock keeping in Enugu Urban, Nigeria, interviewing 75 heads of households. While all respondents were aware of general health and environmental implications, only 4.0% knew livestock could cause climate change. Identified environmental issues included crop destruction (89.3%), urban filth (89.3%), and noise (88.0%), while health issues included disease spread (50.7%), accidents (46.7%), and bad smell (86.7%).

Phil. Caleb Mireri · African Journal of Agricultural Research · Kenya (Kisumu)

This study surveyed 194 urban farmers in Kisumu municipality, Kenya, to assess urban agriculture's role in income, employment, and food supply. It found that most urban farmers and their employees receive very low income, with a mean monthly income of US$135 (US$0.64 per person per day), which is below the acceptable one dollar a day per person. Urban agriculture primarily supplements food requirements for the urban poor and provides income for a few commercial farmers.

Mansur Usman Dawaki, Abubakar U. Dikko, S. S. Noma, Umar Aliyu · Food and Energy Security · Nigeria

This study evaluated pollution risks to food security from urban agriculture in Kano, Nigeria, by sampling soil, water, and lettuce from two wastewater-irrigated sites (Challawa, Jakara) and a control site (Watari). Results showed all sites were contaminated with Cu, and the domestic wastewater site was slightly polluted with Pb and excessively polluted with Cd and Cr. Metal levels in irrigation waters exceeded recommended thresholds, and plants at the domestic wastewater site accumulated metal concentrations (Pb=26.21 mg/kg, Cd=1.03 mg/kg, Cr=28.63 mg/kg, Cu=2.66 mg/kg) that exceeded allowable limits in vegetables, indicating a human ingestion risk.

Teferi Daba Lemma, M. S. A. Rao, M Prasada Rao · Zenith international journal of business economics and management research · Ethiopia

This study assessed the economic sustainability of urban agriculture in central Ethiopia, collecting primary data from 280 urban and peri-urban vegetable farmers. Findings indicated that urban agriculture is a viable livelihood strategy from a financial perspective. However, city administrations and policymakers pay little attention to supporting this sub-sector, suggesting that legal recognition and support would make it a more reliable strategy.

Mekonnen Getahun, Yihenew G. Selassie · Journal of Agricultural Science · Ethiopia

A study investigated the extent of contamination of soil, water, and vegetables from wastewater used for irrigation in urban agriculture in Bahir Dar and Kombolcha, Ethiopia. Soil, water, and vegetable samples were collected and analyzed. While heavy metal concentrations in soil were within permissible levels, wastewater samples showed high nitrate and phosphate levels, and boron concentrations in Borkena River and Lake Tana exceeded permissible limits for irrigation. Wastewater drained to Lake Tana exhibited high turbidity and very high BOD, and lettuce and Swiss chard accumulated higher levels of iron, manganese, and zinc.