Research & reports

Never Assan, Justice Sibanda, Betty Mukuwapasi, Reason Rumbidzai Charachimwe, Edmore Masama · Journal of Frontiers in Multidisciplinary Research · Sub-Saharan Africa

Urban animal agriculture (UAA) in Sub-Saharan Africa is presented as a solution for food security but faces challenges including gender inequality, climate change, inadequate legislation, and environmental degradation. While UAA aims to enhance household food security and alleviate poverty, it also encounters environmental issues such as resource competition, water resource strain, improper manure management, greenhouse gas emissions, noise, and nuisance. Sustainable UAA requires semi-intensive silvopastoral and mixed crop and livestock systems to reduce environmental impact and enhance local food production.

Mahacla Odongo, Caleb Mireri, Peter Mwangi · Environmental Technology and Science Journal · Kenya (Nairobi)

The Nairobi River riparian reserve in Kenya has undergone immense land use and land cover changes over the past 20 years due to urban development. A survey of 650 respondents revealed that urban agricultural activities dominated the upper segment at 69%, commercial ventures constituted 79% of the middle segment, and residential usage comprised 89% in the lower segment. These activities caused significant degradation from crop cultivation of river slopes, pollution infiltration, and loss of biodiversity, indicating a severe depletion of the riparian space's functions.

Fuchaka Waswa, Duncan Gichabe, Ruth Kahuthıa-Gathu · Journal of the Kenya National Commission for UNESCO · Kenya (Ruiru)

This study investigated land use changes in Ruiru Sub-County, Kenya, from 1988 to 2024 using GIS. By 2024, agricultural land had decreased by 45.62%, while urban land use increased by 509%, and bare/rocky areas rose by 133% due to abandoned stone mining. The decline in agricultural land leads to reduced industrial crop areas and a shift to leafy vegetables, with an expected increase in agro-chemical use in intensive peri-urban farming.

Olivier Grünberger, Radhouane Hamdi, Manon Lagacherie, Hanène Chaâbane · Journal of Environmental Science and Health Part B · Africa

Two years of monthly water sampling and hydrological monitoring at the outlet of the Wadi Guenniche watershed (86 km², with rainfed cereal, legume and orchard cultivation and irrigated market gardening) in northern Tunisia, a tributary of the Bizerte coastal lagoon, tested for 469 pesticide active ingredients and metabolites. Twenty-nine pesticide active ingredients and 2 metabolites were detected in the water, 24 of which are authorized for use in Tunisia; 14 of the authorized substances had never before been mentioned in farmer surveys. The five most frequently detected herbicides and metabolites were AMPA (100%), glyphosate (94%), simazine (94%), 2,4-D (70%) and deisopropylatrazine (DIA, 47%). The detection frequency and concentration range suggest phytosanitary pressure and water contamination comparable to the northern Mediterranean shore, indicating a need for further study of pesticide use and fate on the southern shore, particularly in Tunisia.

Abigail Benson, NICHOLAS O EHISIENMHEN, EUNICE T ADEWALE, R ANIMASAHUN-OLADIMEJI, TOBA R ARIBILOLA, RAZAQ A AFIZ, Augustine Okeke, Oliver P. John, Idris Ahmad Isa, BADRAT O IMRAN, KELVIN D DIRISU, OMOTOYE O OMISORE · Greener Journal of Agricultural Sciences · Nigeria (Ondo State)

This study assessed the impact of urbanization on agricultural land in Akure South Local Government Area, Ondo State, Nigeria, using populated figures and land use data from satellite images for 2002, 2012, and 2022. GIS analysis revealed an increase in settlement and a decrease in agricultural land from 2002 to 2022. Urbanization significantly decreased agricultural land, farming activities, and farm size, driven by increasing settlement and built-up areas.

Shabu Terwase · International Journal of African and Asian Studies · Nigeria

This study assessed the impact of urbanization on agricultural land in Makurdi Local Government Area, Benue State, Nigeria, using population figures and land use data from 1997, 2007, and 2017. GIS analysis revealed an increase in settlement and a decrease in agricultural land, with 99.51 hectares of agricultural land converted to settlement between 1997 and 2017. Urbanization significantly decreased agricultural land, activities, and farm size in the study area.

Mekonnen Amberber Degefu, Mekuria Argaw, Gudina Legese Feyisa, Sileshi Degefa · ENVIRONMENTAL SYSTEMS RESEARCH · Ethiopia

This study characterized and compared the Spatio-temporal responses of ecological land to urban landscape dynamics in Bahir Dar, Addis Ababa, Adama, and Hawassa cities in Ethiopia for the last three decades (1990–2020). Three sets of Landsat satellite images, field observations, and urban land indexes were used to produce landscape maps and geo-spatial data analysis. Results showed that in all cities, ecological land had changed intensely regarding its quantity and spatial pattern, and the substantial expansion of built-up ecosystems was manifested at the cost of ecological land.

Bereket Geberselassie Assa · Civil and environmental research · Ethiopia

A study of Wolayta Zone Sodo Zuria Woreda in southern Ethiopia used GIS and remote sensing to analyze how human intervention affects the agricultural system. It found that urbanization driven by demand for residential land, a 2.66% increase over nine years, has produced food insecurity and raised crop production costs in local markets. Forestland declined at a rate of 0.295% per year, of which 0.09% was converted to residential land. Land use classification from 30 m Landsat 7 imagery was evaluated using the Analytic Hierarchy Process with a consistency ratio of 0.016%, and the study notes that the impact of deforestation on urban agriculture and livelihoods in this part of southern Ethiopia's highlands had not previously been scientifically studied.

Joshua Jonah Kunda, Ahmed Abubakar Jajere, E. A. Otabe, Chindo Musa Muhammed, Umar Muhammed Bibi, Yusuf Maina-Bukar · Environment and Pollution · Nigeria

This study in Makurdi, Benue State, Nigeria, used geospatial technology to assess agricultural land vulnerability to flooding, deriving factor weights (rainfall 25%, elevation 22%, slope 20%, drainage density 13%, land use/cover 12%, soil type 8%) through pairwise Analytical Hierarchy Process comparison (consistency ratio 0.078) and a weighted overlay model in ArcGIS 10.4. Farmland along the floodplains of the River Benue fell within the very highly vulnerable category, with elements at risk totaling 537.6 units of farmland (66.1%), 40.5 units of irrigation land (5.0%), and 125.8 units of built-up land (15.5%).

Achamyeleh Gashu Adam · IntechOpen eBooks · Ethiopia

A case-study and desk-review analysis of how new urban built-up properties form in the transitional peri-urban areas of Ethiopia. These areas are described as sites of intense competition between agricultural and non-agricultural land use, where rural agricultural land rights are vanishing. The study finds that both formal and informal actors play a significant role in converting peri-urban agricultural land into non-agricultural urban built-up property, and that these properties result from land-use conversion through both formal and informal channels.

Erik Engel, Karin Fiege, Anja Kühn · · Africa

The UFISAMO project analyzed urban agriculture (UA) in Maputo and Cape Town. In Maputo, UA is the main income source for about 5% of the population, though it often does not cover monthly food costs, and a major challenge is the uncontrolled application of pesticides due to mono-cropping. In Cape Town's townships, UA plays a negligible role in income and food security due to small plots, sandy soils, water stress, and weak market links.

Shailesh Deshpande, Priyanka Verma, Piyush Yadav, Jay Gubbi, P Balamurali · Asian Journal of Geoinformatics · South Africa (Johannesburg)

Land Use Land Cover (LULC) changes in Johannesburg City, South Africa, were analyzed using Landsat imagery from 2000 to 2016. The analysis revealed that impervious surface increased by 57.03% during this period, leading to a 47.8% loss of urban vegetation (grass, tree cover) and urban agricultural land. Additionally, soil and water loss amounted to 16.75%.

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.

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.