Research & reports

Loyane Ferreira da Matta, Monique Cleia de Pontes Bandeira CARVALHO, Josué Rodrigues Gomes, Juliana do Nascimento Chagas Pessanha, Érika Eberlline Pacheco dos Santos · LA Referencia (Red Federada de Repositorios Institucionales de Publicaciones Científicas) · Brazil (Campos dos Goytacazes)

A pedagogical garden project was implemented at Escola Municipal Santa Terezinha in Campos dos Goytacazes, Brazil, to teach the importance of agroecology, the environment, and healthy eating. The project involved weekly activities where students participated in workshops, courses, meetings, study groups, and garden construction, based on a bibliographic survey of pedagogical gardens, agroecology, and urban agriculture.

Nicolette Tamara Jonkman, Karsten Kalbitz, Huig Bergsma, Boris Jansen · Land · Africa

This case study investigates the relationship between prior land use, current management, and soil quality at six urban agriculture (UA) sites in Kisumu, Kenya, and Ouagadougou, Burkina Faso. A soil survey determined the soil macronutrient and mineral composition. Results indicate that three UA sites predate surrounding urban development, and soil nutrient data suggest these sites were likely chosen for their soil.

Inanpi Hidayati Sumiasih · Jurdimas (Jurnal Pengabdian Kepada Masyarakat) Royal · Indonesia (Jakarta)

In Jatinegara Baru Housing, East Jakarta, Indonesia, an urban farming program was conducted from March to December 2022 for residents and santri of the Al Jabar community. The program included cultivating vegetables in narrow yards, utilizing green spaces, and training in compost and POC production. Evaluation showed that participant understanding increased from an initial 10% to 100%, the activity was rated "very beneficial," and the combined theory and practice method was considered highly suitable for participants.

Govinda Prasad Devkota · Pragyaratna प्रज्ञारत्न · Nepal

This participatory action research in a public high school in Nepal explored the applicability of urine diversion toilets for organic vegetable production and sanitation improvement. It found that urine diversion toilets prevent surface water pollution and improve students' hygiene. Additionally, using human urine as fertilizer increased vegetable production by 40% compared to animal fertilizer in plots of the same area.

Isaac Asirifi, Korbinian Kaetzl, Steffen Werner, Stefanie Heinze, Felix K. Abagale, Marc Wichern, Manfred Lübken, Bernd Marschner · Journal of soil science and plant nutrition · Ghana

This study evaluated the agronomic and soil fertility effects of using municipal wastewater or anaerobically treated wastewater for irrigation and applying biochar to a soil from the Guinea savanna agroecological zone of Ghana. In a pot trial, lettuce and carrot were grown on soil mixed with raw biochar, water-washed biochar, or biochar used as wastewater filter material at 20 t ha−1, and irrigated with untreated municipal wastewater, anaerobically treated wastewater, or clean water. Results indicated higher crop growth and yields (up to 90% increase) with untreated and anaerobically treated wastewater than clean water, with anaerobically treated wastewater being more beneficial than untreated wastewater (up to 10% increase). Combining raw biochar with anaerobically treated wastewater increased pH, CEC, and P availability in the highly weathered acidic soil.

Maraike Probst, María Gómez‐Brandón, Cecilia Herbón, María Teresa Barral, Remigio Paradelo · Applied Soil Ecology · Spain

This study evaluated fungal and bacterial communities in 40 soil samples from 10 urban allotment gardens in Santiago de Compostela, Spain, using DNA sequencing. While microbial richness was comparable to less anthropogenically influenced urban soils, the deterministic effect of soil properties and geographical distances was negligible. Fungal and bacterial communities followed a random distribution and formed very small, often unconnected, microbial association modules, suggesting potential implications of anthropogenic activity for soil health and ecosystem functionality.

Tirto Wahyu Widodo, Damanhuri Damanhuri, Ilham Muhklisin, Sonia Budiarti, Dian Agustina · Jurnal Ilmu Pertanian Indonesia · Indonesia

An experiment examining the response of rice plants to non-soil planting media based on alternate wetting-drying irrigation, aimed at soilless rice cultivation as an urban farming method for subsistence food production. Conducted at a screen house in Sumberjeruk Village, Jember Regency, Indonesia, from January to May 2022, the study used a two-factor, fully randomized factorial design with three replications: husk-to-water ratio (0:1, 1:4, 1:6, and 1:8, total media volume 25 L) as the first factor, and rice variety (Inpari 46 and IR 64) as the second. The combination of a 1:6 husk:water ratio with the Inpari 46 variety had a significant effect on the number of productive tillers (25.17 stems) and grain weight per hill (34.07 g); the 1:6 ratio showed no significant difference from 1:4 in total grain number (124.21) or full grain number (83.52). The Inpari 46 variety showed the highest values for total grain number (133.07), full grain number (84.88), and 1000-seed weight (22.43 g). The study concludes that husk-and-water media at the right ratio is an ideal medium for landless rice cultivation because it can supply oxygen to the media.

Alpana Kusum · · Global

This chapter reviews composting, the conversion of organic waste into nutrient-rich compost, distinguishing between municipal solid waste, agricultural residues, and industrial organic waste as source materials, and describing aerobic composting, anaerobic composting, and vermicomposting methods. It states that managing the carbon-to-nitrogen ratio, moisture, temperature, and aeration is important for effective composting, and lists benefits including improved soil fertility, nutrient recycling, water-holding capacity, erosion control, and reduced greenhouse gas emissions through carbon sequestration. It covers applications in agriculture, horticulture, landscaping, urban gardening, land reclamation, and bioenergy production, while also noting challenges such as managing contaminants, odor control, monitoring, and regulatory compliance.

Suman Kumar Sourav, C. T. Subbarayappa, D. C. Hanumanthappa, Mudalagiriyappa, Prem José Vazhacharickal, Andrea Mock, Mariko Ingold, Andreas Buerkert · Nutrient Cycling in Agroecosystems · India

This study investigated how three rates of mineral nitrogen addition combined with rainfed versus irrigated conditions affected CO2 emissions from typical crops during the wet (Kharif) and dry (Rabi) seasons on a Nitisol in Bengaluru, South India. Two two-factorial split-plot experiments were conducted under rainfed and irrigated conditions from 2017 to 2021, using maize, finger millet, and lablab, and the vegetables cabbage, eggplant, and tomato or chili. CO2 emissions were measured with a Los Gatos Research multi-gas analyzer from 7:00-11:30 a.m. and 12:30-6:00 p.m., with CH4, NH3, and N2O found negligible. Regardless of irrigation, season, crop, or nitrogen level, afternoon CO2 emission rates were 2-128% higher than morning rates. Diurnal differences ranged from 0.04-1.61 kg CO2-C/ha/h in the irrigated field and 0.20-1.78 kg CO2-C/ha/h in the rainfed field. In the rainfed field, high-nitrogen plots emitted 56.4% more CO2 than low-nitrogen plots, versus only 12.1% more in the irrigated field. A linear mixed model showed nitrogen fertilization enhanced CO2 emissions, most strongly in rainfed crops; soil moisture enhanced emissions in rainfed crops but decreased them under irrigation, while soil temperature at 5 cm depth enhanced emissions in both fields.

Borja Ferrández-Gómez, Juana D. Jordá, Antonio Sánchez‐Sánchez, Mar Cerdán · Sustainability · Europe

A study of nine soils (Technosols) developed over construction debris in Alicante, southeast Spain, analyzing mineralogy, elemental composition and metal availability over two consecutive years, 2019 and 2020. The soils were similar to forest soils in the same area, with no evidence of asbestos clays or excess harmful elements, though DTPA extraction revealed high levels of Mn and Zn in some soils. Organic carbon and DTPA-extracted metal content differed between the two years with no clear relationship observed between them; organic matter content was higher and DTPA-extracted elements were lower in 2019, which the authors attribute to above-average rainfall that year possibly washing away dissolved materials and fine soil particles while promoting natural vegetation growth that increased organic matter and immobilized elements. The study concludes that because metal mobility varies with weather and soil characteristics, and because urban soils develop on materials that require attention despite the benefits of green space, annual monitoring plans for heavy-metal availability are needed, particularly where plants are grown for human consumption, along with controls on vegetables grown in these soils and restricted garden use if problems are found.

Muhammad Fawwaz, Muhammad Fikri Akbar, Madziatul Churiyah, Sholikhan · PRIMA PORTAL RISET DAN INOVASI PENGABDIAN MASYARAKAT · Indonesia

A community-engagement report on establishing a "Waste Bank Gallery" in Kampung Mergosono, led by PKK (Family Welfare Movement) mothers, to address urban waste management. The program provided counseling on waste issues, management solutions, the Waste Bank Gallery scheme, handling procedures, task delegation, schedules, and stakeholders, and taught practical recycling of valuable waste plus using organic waste as fertilizer for urban farming. The outcome was described as effective dissemination of the Waste Bank Gallery program, contributing to improved waste management in the area.

Julio César García-Colin, Carlos Díaz-Delgado, Humberto Salinas-Tapia, Carlos Roberto Fonseca, María Vicenta Esteller Alberich, Khalidou M. Bâ, Daury García-Pulido · Water · Spain

Using lysimeter data from a golf course in Spain, researchers designed and validated a sustainable urban agriculture drainage system with water reuse (SUADS-WR) based on a daily water balance, estimating reference evapotranspiration via the Penman-Monteith or Hargreaves-Samani methods. Compared with experimental data, estimated irrigation depths were lower than the water actually supplied, and estimated percolation matched measured field drainage. Implementing SUADS-WR allowed harvested water to cover more than 38% of the crop's annual water demand.

Reginawanti Hindersah, A. Marthin Kalay, Rion Suaib Salman, Wilhelmina Paays, Saon Banerjee · Current Research in Agricultural Sciences · Indonesia

A study of leafy vegetable cultivation (cabbage, water spinach, spinach) in urban farming areas along Ambon Bay in Ambon City, Indonesia, used 11 years of weather data verification combined with qualitative interviews with farmers to examine adaptation to disease and yield loss caused by excess wet-season rainfall. Annual rainfall varied, ranging from 3,950-5,264 mm in 2010-2013 and 2017-2020 versus 2,017-2,995 mm in 2014-2016; farmers adapted by installing plastic rain shelters, shortening planting distance from 20 cm to 10 cm, and changing their planting calendar.

Samir A. Haddad, Hossam Abdelmageed, Abdelaziz Saleh, Samia Ahmed, M. M. Abd El-Azeim, Joanna Lemanowicz, Gaber E. Eldesoky, Omar Saad · Sustainability · Egypt

Incubation and pot experiments under controlled greenhouse conditions used clay and sandy soils collected from peri-urban agricultural areas near El-Minia, Egypt, to test how different biochar application rates affected faba bean growth, cellulose decomposition, nodulation, and carbon-cycling enzyme activities. Biochar at 3 kg/sq·m was the most effective treatment, followed by 2 kg/sq·m; counts of cellulose-decomposing microorganisms rose to a high level in both soil types by 60 days of incubation and then declined by 90 days regardless of biochar rate, while clay soil showed significantly greater fresh and dry weight than sandy soil, and biochar overall improved soil health, microbial communities, and faba bean nodulation and growth.

Poonam Bewtra · Current Agriculture Research Journal · India

Food forests involve planned agroforestry. The abstract states that, like a real forest, a food forest requires no pesticides, herbicides, weeding, crop rotation, mowing, or digging, and ensures the sustainability of flora, fauna, birds, animals, and particularly bees. This is a case study of one such food forest, Vanya Organic, realized by one of its owners, Mr. Patanjali Jha, who grew native trees, creepers, and shrubs in combination with symbiotic vegetation to maximize carbon sequestration, forest cover, and usable by-products. A key component is Vetiver grass, and Jha argues that food forests and vetiver plantations should be planned and established together, terming the combination a "Regenerative Food Forest." The abstract states that Compressed Bio Gas (CBG) or Renewable Natural Gas (RNG), described as a "green fuel," can be derived from the agricultural waste and other biomass that regenerative food forests produce in abundance; a CBG plant produces sulphur-stripped, automotive-grade methane along with a high-quality organic fertilizer by-product approved for regular use by the Ministry of Agriculture, and the abstract argues for linking CBG plants with regenerative food forests to provide jobs, increase farm incomes, and bring sustainable changes to air, water, and soil quality over time. The case study is stated to have been prepared with the owner's consent and approval.

Jean Pascal · Biodiversity online journal. · Global

Noting that insects constitute most of the biodiversity on Earth and provide a wide range of services to society while being threatened by human activities such as habitat destruction and urbanization, this article assesses advances in understanding the impact of insects on sustainable food production in low-income countries. It focuses on two research topics that have emerged in recent years: entomophagy combined with the creation of small household farms rearing insects for sale (the Thai example), and the use of insects to improve soil fertility and nutrient availability (the Zai example). The article advocates considering the diversity of solutions and adaptations found in nature, arguing that the ways local communities and ethnic groups use natural resources are vast and should be seen as a source of inspiration for scientists developing sustainable food systems.

Aikaterini N. Martini, Μ. Papafotiou, Ioannis Massas, Nikoleta Chorianopoulou · Plants · Greece

Origanum dictamnus, a perennial herb endemic to Crete, Greece, was grown at two cultivation sites in Athens — an extensive green roof and ground level next to a moderate-traffic road — in two substrate types at 10 cm depth, to examine growth along with nutrient content (N, P, K, Na) and heavy metal accumulation (Cu, Pb, Ni, Mn, Zn, Fe) in its tissues. Plant growth was favored by the soil substrate but was also satisfactory in the soilless substrate. Cultivation site affected heavy metal accumulation, with higher concentrations found in leaves and flowers at street level, though no differences appeared in roots. Washing reduced heavy metal concentrations only in leaves grown at street level. Substrate type significantly affected manganese concentration in all tissues and iron concentration in roots, with the highest values in the soil substrate. The species could be cultivated on sustainable green roofs, preferably on a soilless substrate to reduce structural weight, but careful selection of the cultivation site was identified as necessary to minimize contamination with environmental pollutants when human consumption is intended.

Susana Moreira Padrão · Interagir pensando a extensão · Brazil

An essay reflecting on the potential of agroecological agriculture in Brazil within the context of the health crisis caused by the COVID-19 pandemic and its likely economic and social consequences. It presents economic and social indicators of rising unemployment and poverty, arguing that social inequality is likely to worsen in this scenario, with an immediate impact on rising food insecurity and hunger. Examples such as the Agroecological Fair at the State University of Rio de Janeiro (UERJ), collective and community gardens in favelas, and productive backyards are cited as showing that actions reaching the most vulnerable population are possible to implement. The essay argues that agroecology and urban agriculture contribute effectively to promoting food and nutritional security and health, aiming at the human right to adequate food and population involvement in agroecology-based food cultivation, in pursuit of food autonomy.

Nimas Sekarlangit, Prasasto Satwiko · MODUL · Indonesia

This paper addresses how the COVID-19 pandemic forced people worldwide, including in Indonesia, into new living habits. It notes that experts link recurring zoonotic pandemics closely to human consumption of wild animals and livestock, and states that plant-based food sources have already been shown to meet humans' complete nutritional needs. The "arsitektur nabati" (plant-based architecture) discussed here combines human activity spaces with food plants within a local context, and is presented as an integrated solution to the challenges of preventing recurring zoonotic pandemics, nutritional sufficiency, biodiversity, and urban living-environment quality. Using recent COVID-19-related information, the paper discusses the connection between the pandemic and plant-based architectural design, studying student and professional architects' works that respond to the idea of urban agriculture. It concludes that plant-based architecture can serve as an early mitigation effort against pandemic disasters by providing good air quality and lighting for spaces, promoting occupant health, and providing food security under conditions of limited land.

Mahsa Tarashkar, Mansour Matloobi, Salman Qureshi, Akbar Rahimi · Ecological Indicators · Global

This study investigated the effects of tea waste compost on the growth traits of radish (Raphanus sativus L.) and explored whether a clean carbon dioxide source from urban households could contribute to sustainable production. Tea waste gathered from urban households was decomposed for four months and mixed at 0–75% by volume with loamy garden soil; using a split-plot design, one greenhouse was enriched to an elevated CO2 concentration of 1500±100 ppm while a second was kept at the ambient level of 500±20 ppm. Results showed that elevated CO2 negatively affected radish yield, biomass accumulation, and vegetative growth parameters, while increasing volumes of tea waste compost, up to 75%, improved growth traits. At 75% tea waste compost, elevated CO2 had the same effect on growth traits as the normal level, showing a positive effect on total fresh weight but negative effects on total dry weight, leaf dry weight, and total leaf area. The study attributes the strongest support for radish growth at the highest compost volume (75%) to its high nitrogen content.

B. BOLOU-BI Emile, Philippe GUETY Thierry, TRAORE Adama, KONE Brahima · African Journal of Agricultural Research · Global

To evaluate the effect of biochar on tomato production in acidic soil, a complete randomized block design with 5 replications tested four treatments: 0% (T0, control), 8% (T1), 12% (T2) and 16% (T3) biochar application, measuring plant height, stem diameter, leaf number, fruit number and biomass. Plants receiving biochar (T1, T2, T3) were taller than the unamended control (T0); T1 plants averaged 12±2 fruits per plant, while T0 control plants produced no fruit at all, and T2/T3 fruit counts fell between the control and T1. Soil chemical analysis showed exchangeable cations, cation exchange capacity, pH, soil organic matter, total nitrogen and C/N ratio all higher than the initial soil, though treatments had no significant effect on soil enzymic activity. The study recommends recovering waste as an organic material source in urban horticulture and open-field cultivation to restore soil fertility.

Verónica Arcas‐Pilz, Xavier Gabarrell, Francesco Orsini, Gara Villalba · The Science of The Total Environment · Europe

A literature review mapped technologies for recovering nitrogen (N) and phosphorus (P) from urban waste sources for use in urban agriculture (UA), distinguishing (1) food, organic and biowaste sources, for which 7 recovery strategies were identified, from (2) wastewater, for which 11 were identified, and assessed the potential for the metropolitan area of Barcelona. Recovering nutrients through composting and anaerobic digestion of organic waste, composting of wastewater sludge, struvite precipitation and ion exchange in wastewater effluent could, depending on the strategy, meet current and prospective UA phosphorus demand 2.7 to 380.2 times over and nitrogen demand 1.7 to 117.5 times over. Despite this technical potential, the review concludes that current perceptions, legislation and implementation and production costs relative to existing markets do not facilitate the actual application of these nutrient recovery strategies.

Ministère de la Transition écologique · Ministère de la Transition écologique (France) · France

France's Ministry of Ecological Transition's official page on the mandatory source-sorting of biowaste (food and garden waste). Per EU law and France's 2020 anti-waste law, source-sorting became mandatory nationwide for all professionals and households from January 1, 2024. Biowaste is described as making up one-third of unsorted household waste; the government's 'Fonds vert' has supported local authorities' sorting infrastructure since 2023.

Jiajia Zhang, Zishuang Li, XiaoLin Zhou, Wencheng Ding, Xuexia Wang, Meng Zhao, Hongjie Li, Guoyuan Zou, Yanhua Chen · Science of the Total Environment · China

A 2023 study using an 11-year wheat–maize rotation field trial in China to test how long-term application of pig- and cow-manure compost affects soil microplastics (MPs). The composts themselves contained 3,547 and 4,520 items/kg respectively; soils under long-term application held 144–287 and 140–316 items/kg, significantly more than unamended soil, and abundance rose with application rate. Compost-derived accumulation reached 1.73 × 10⁸ to 7.22 × 10⁸ items per hectare, accounting for 43.0–75.9% of total soil MPs, with the contribution doubling when the application rate doubled. Particles under 1 mm made up 31.0% of MPs in the composts but 43.8% in amended soils, size and abundance fell with depth, and particle surfaces showed complex weathering with attached soil mineral colloids — evidence, the authors conclude, that compost-derived MPs are progressively fragmented and degraded in soil after application. Polyethylene and polypropylene fragments and polyethylene terephthalate fibres dominated.

Eugenio-Gozalbo M., Ramos-Truchero G., Suárez-López R., Romanillos M.S.A., Rees S. · Education Sciences (MDPI), 12(3):168 · Europe

A study assessing a garden-based teaching unit on 'Food and Nutrition' against a traditional textbook-based unit. The garden-based sequence produced more comprehensive student understanding and better preparation for real-life dietary decisions, representing an educational improvement over traditional teaching.