Research & reports

Matteo Clementi, Valentina Dessì, Mariana Pereira Guimarães · TERRITORIO · Global

The bize_UrFarm research explores urban agriculture's potential to integrate into urban and building metabolism by utilizing water, soil, and waste, and to strengthen urban green infrastructure. This research introduces building surfaces as a resource for urban agriculture, challenging the previous view of them as impediments in urbanized contexts.

Na Wei, Madelynn Nakaji-Conley, Jiaqi Tan · Microbial Ecology · Global

In urban farming fields of different ages and multiple genotypes, the relative abundance, richness, and microbial networks of putative plant pathogenic, mycorrhizal, and saprotrophic fungi in the rhizosphere were tracked over two years. Pathogenic fungal abundance was higher in older fields than younger fields, consistent with pathogen accumulation over time, while mycorrhizal fungal abundance decreased in older fields and saprotrophic abundance remained similar between younger and older fields. Mycorrhizal fungal richness declined in older fields and over the two years, with a corresponding decrease in network links, whereas saprotrophic fungi showed increased network links in older fields and pathogenic fungal networks remained similar across fields.

Robert C. Brears · Cambridge University Press eBooks · Global

A book chapter on circular urban agriculture, discussing strategies for sustainable food production in rapidly growing cities. It surveys urban farming methods including rooftop gardens, vertical farming, hydroponics and community gardens, framing resource efficiency — using waste streams, conserving water, and minimizing inputs like soil and fertilizer — as the core of the circular approach, and describes water conservation and recycling (drip irrigation, greywater reuse, rainwater harvesting) and nutrient recycling through biosolids as key components for improving soil quality and productivity.

Rattan Lal · CABI eBooks · Global

A chapter discussing soil scientist Rattan Lal's synthesis of spirituality and philosophy, drawn from Sanskrit/Vedic teachings passed down by his grandmother, with soil science. It traces the historical development of soil and plant science disciplines and states that more change may occur between 2020 and 2050 than in the preceding 10 millennia, listing carbon farming, nutrition-sensitive agriculture, soil-less urban farming and sky farming as future agricultural practices, and noting that the UN Agenda 2030 Sustainable Development Goals depend on soil protection, restoration and management.

Florence Rezende Leite, Maria Lúcia Pereira Antunes, Diogo Aparecido Lopes Silva · Sustainable Production and Consumption · Global

A life cycle assessment (LCA) comparing the environmental performance of a conventional ceramic roof (CR) and a modular green roof (GR) planted with the edible species Pereskia aculeata. Primary data came from experimental GR prototypes monitored for one year, including irrigation volumes, plant development and rainwater retention across 50 rainfall events; secondary data were modeled from the ecoinvent database and literature. The analysis had three stages: comparing CR and GR construction and first-year use, sensitivity/uncertainty analysis of alternative GR materials, and a 30-year projection of use-phase impacts. In stage one, GR outperformed CR in 11 of 14 impact categories, with total normalized impacts 13% lower; 80% of CR's impact came from ceramic tile production, while in GR polymer components dominated, with polypropylene accounting for 82% of fossil depletion and polyester for 95% of ozone depletion. Substituting alternative polymers for the module and filter layers cut marine and freshwater ecotoxicity by over 70%. The optimized GR scenario had 71% lower normalized impacts than CR and outperformed it in 13 of 14 categories, with the 30-year projection confirming GR's continued advantage.

Isabelle van der Zanden, Gelieke G.T. Steeghs, Lieke Moereels, G. F. Veen · Agroforestry Systems · Global

This study examined litter decomposition dynamics in food forests, perennial multi-layered food production systems gaining popularity as alternatives to intensive, input-dependent agriculture that rely on nutrient recycling via litter decomposition. Litter from Alnus glutinosa (black alder), Corylus avellana (common hazel), and Castanea sativa (sweet chestnut), ranging from high to low litter quality, was decomposed in food forests planted on former grasslands and compared with neighboring grasslands. Litter bags of varying mesh size were used to assess the relative contribution of microbes and micro-, meso-, and macrofauna to short-term litter mass loss, and abundance and biomass of key decomposer groups were quantified. Decomposer communities differed between land use types: food forests harbored a higher abundance of oribatid mites but a lower abundance and biomass of earthworms and lower arbuscular mycorrhizal fungi biomass than grasslands. Overall litter mass loss differed little between the systems, except that high-quality litter accessible to the full decomposer community lost more mass in grasslands. The lowest-quality litter (sweet chestnut) decomposed slowest, with its rate unaffected by mesh size or land use. High-quality leaf litter generally decomposed faster in grasslands than in food forests, and the distinct decomposer communities in young food forests did not favor breakdown of recalcitrant litter.

Robert C. Brears · Cambridge University Press eBooks · Global

This book chapter outlines best practices and strategies for cities transitioning toward becoming circular and liveable. It covers applying circular economy principles across urban sectors including waste management, energy efficiency, transportation and urban agriculture, using a 5R approach — reduce, reuse, recycle, restore and recover. It presents strategies such as energy-efficient financing for building retrofits, grant programmes for water reuse, and e-waste collection and disposal systems, and discusses public participation and stakeholder collaboration through a Quadruple Helix model involving academia, industry, government and civil society. Case studies from Amsterdam, Paris and Copenhagen illustrate circular business models and governance frameworks, and the chapter sets out a roadmap centered on education, policy innovation and community engagement.

Pierre‐Alexandre Deyris, Franck Pélissier, Claire M. Grison, Claude Grison · Journal of Hazardous Materials Advances · Global

Herbicide use worldwide has doubled over the past 30 years, and diuron contamination of tropical aquatic ecosystems — affecting food crops such as pineapple — has been reported across Southeast Asia, the Pacific, and Africa. This perspective article examines taro (Colocasia esculenta), a widely cultivated crop whose tubers are consumed locally, as a nature-based means of mitigating diuron impact on tropical aquatic ecosystems through rhizofiltration, i.e., phytoaccumulation of the herbicide by the roots. Analysis of treated tubers found that diuron levels in the tuber core were below recommended European standards, indicating the tubers could remain edible for the local population and confirming compatibility with existing food uses.

Pires M. J. F. C. D. S., Ribeiro S. A., Ferreira L. S., Antunes L. F. S., Uzeda M. C., Correia M. E. F. · Environmental Monitoring and Assessment · ブラジル・リオデジャネイロ市

A survey testing whether agroecological urban agriculture plots — described as remnants of biodiversity that also provide ecosystem services, food security and income — can shelter soil fauna in an urban setting. Fifteen areas forming a gradient from different plantations to forest were selected in the Campo Grande and Vargem Grande neighbourhoods of western Rio de Janeiro. At each area a transect of three sampling points 5 m apart was established; soil mesofauna was sampled with a specific auger from the litter layer down to 10 cm, and earthworms by the TSBF method at 0–10 cm. Soil fertility and texture were analysed at each point, landscape features were measured within buffers around each site, and multivariate techniques including principal component analysis were used to identify which soil attributes and landscape features most affect the occurrence and abundance of soil invertebrates.

Sarah Kakadellis, Herman D. Delgado, Russell Teall, R. Gándara León, Christopher W. Simmons, Edward S. Spang · Journal of Agriculture and Food Research · Global

This greenhouse experiment tested liquid food waste-derived digestate (FWDD) as a biofertilizer for community learning gardens, growing tomatoes (Solanum lycopersicum) under four treatments: potting medium alone, medium with synthetic mineral fertilizer, medium with compost, and medium with a compost-FWDD blend. The mineral-fertilizer control produced the highest total fruit yield, but total edible fruit yield and total fruit weight were similar between the control and the compost-FWDD blend, which produced the largest average fruit weight; compost and compost-FWDD treatments produced lighter, tarter—though not more acidic—tomatoes, and no detrimental soil effects from FWDD were observed, though the authors note further research is needed to assess social perceptions and life cycle impacts.

FAO · FAO (FAOSTAT Analytical Brief) · Global

According to a FAOSTAT analytical brief, global agricultural use of inorganic fertilizers rose 34 percent, from 142 million tonnes in 2002 to 190 million tonnes in 2023. Per-hectare application rates of nitrogen, phosphorus and potassium all increased over the period, and world production reached 208 million tonnes in 2023, up 40 percent since 2002.

U.S. Geological Survey (USGS) · U.S. Geological Survey (USGS) · Global

This is the Phosphate Rock entry of USGS's annual Mineral Commodity Summaries 2025. U.S. 2024 marketable production was 20,000 thousand metric tons (about 20 million tons, valued at $2 billion), with net import reliance at 13% of apparent consumption and import sources (2020-23) at Peru 98%, Morocco 2%. World mine production was estimated at 240,000 thousand metric tons in 2024 (China, Morocco, the U.S., and Russia leading), world reserves at 74,000,000 thousand metric tons, with Morocco alone holding 50,000,000 thousand metric tons. World P2O5 consumption in fertilizers was 47.5 million tons in 2024, projected to rise to 51.8 million tons by 2028.

Chimwemwe Chiutula, Andrew G. Mtewa, Amon Abraham, Richard Lizwe Steven Mvula, Alfred Maluwa, Fasil Ejigu Eregno, John Njalam'mano · International Journal of Environmental Research and Public Health · Malawi (Blantyre)

At the Soche Wastewater Treatment Plant in Blantyre, Malawi (built in the 1950s, current design flow 4,100 m³/day), whose effluent irrigates nearby gardens, researchers measured heavy metals by atomic absorption spectrophotometry in effluent, soil and six vegetables (three exotic Brassica varieties plus indigenous pumpkin, sweet-potato and amaranth leaves). Soil zinc reached 56.4 ± 0.5 mg/kg against a WHO limit of 36 mg/kg; vegetable stems reached 4.65 mg/kg chromium (limit 2.3) and 4.09 mg/kg lead (limit 0.3), and leaves 0.31 mg/kg cadmium (limit 0.2). Health risk indices peaked at 92.28, far above the safe threshold of 1. Limitations: sampling at a single time point (November) with no seasonal variation, and total-element rather than speciation analysis.

Gerald Quarcoo, Samuel Armoo, Augustina Angelina Sylverken, Matthew Glover Addo · PLOS ONE · Ghana

A study of 179 urban vegetable farmers in Accra (n=125) and Tamale (n=54), Ghana, with stool samples from 168 of them. Tamale recorded 0% soil-transmitted helminth infection, while Accra recorded Ascaris lumbricoides 5.1%, Ancylostoma duodenale 2.5% and Strongyloides stercoralis 0.8%. Not using personal protective equipment was strongly associated with infection (odds ratio 4.3, 95% CI 1.03–18.00, p=0.04); PPE use was 72% in Tamale versus 41% in Accra. The results indicate that occupational health risk in urban farming varies sharply by site and working practice. Limitations include farmers declining to give samples for superstitious reasons and the near-absence of prior studies on this population.

Edwards F., Mercer H. · Local Environment (Taylor & Francis), 29(10) · Global

An ethnographic study of ShareWaste, an online community-composting platform in Sydney and Canberra that connects food-waste donors directly with households hosting compost heaps to divert waste from landfill. Drawing on environmental humanities and discard studies, it explores the relationships among people, soil, compost, and food waste and the community-building these practices foster.

Alessio Russo · Land Use Policy, 149, 107410 · Global

A conceptual paper extending the ecological-restoration paradigm of rewilding into urban and food contexts, arguing that multispecies-based 'urban rewilding' can simultaneously enhance climate resilience, biodiversity recovery, food-system robustness, water sensitivity and community participation. It also flags trade-offs such as green gentrification and land availability, opening new debate within productive green infrastructure.

· Sustainability · Global

Evaluates crushed brick and crushed concrete of varying particle sizes as extensive green roof substrates through simulated drought and rooftop experiments, turning low-value construction waste into a growing resource.

· Recycling · Global

A scoping review of 68 open-access articles from 24 countries (2012–2022) mapping the reuse and recycling of alternative materials in green roof structures within a circular economy framework.

· Journal of Scientific Research and Reports · Global

Comprehensive analysis of urban agriculture's potential, challenges, and socio-economic impacts. Examines successful citizen-driven models and barriers to scaling.

Terrile R., Martinez N., Brunotto F., Rizzi M., Scarpeci T., Tornaghi C. · Frontiers in Sustainable Food Systems · Rosario, Argentina

Analyses and characterises urban waste-based composts used on two city farms in Rosario, evaluating their use for soil fertility management in agroecological horticultural production.

Urban Agriculture Research Group · ResearchGate · Global

Investigates how rooftop gardening practices utilize small and unconventional spaces to increase cities' self-reliance in food production

Lima, P., Mwangi, E., Sousa, H., Park, J. · Nature Climate Change · Global

Global analysis of 250 agroforestry systems showing 4-8 tons CO2/ha/year sequestration compared to 0.5-1 ton for monoculture. Scaling could sequester 3-4 gigatons CO2 annually.

Sun Yeong Lee, H. S. Lee, Yong-Han Yoon, Jin-Hee Ju · Journal of people, plants, and environment · Global

This study analyzed the growth and quality of cherry tomatoes (CTs) and nasturtiums planted at different ratios (CTs only, 2:1, 1:1, 1:2, nasturtiums only) on rooftops and walls in building-integrated urban agriculture. Cherry tomatoes planted alone showed significant growth compared to companion planting. The 2:1 ratio of CTs to nasturtiums (C2N1) resulted in the highest plant weight and sugar concentrations for CTs on rooftops and walls, and nasturtiums also had larger leaves and flowers in this ratio. CTs generally grew better on walls than rooftops when companion planted with nasturtiums.

Weonjung Sohn, Ibrahim El Saliby, Andrea Merenda, Sherub Phuntsho, Stefano Freguia, Jing Guan, Li Gao, Sungyun Lee, Ho Kyong Shon · Desalination and Water Treatment · Global

This study investigated the efficiency of urine-derived fertilizer compared to commercial fertilizers using three growing systems: nutrient film technique, pot-drench, and deep-water culture. The research found comparable growth responses in parsley, rhipsalis, coriander, and basil across various parameters like biomass and nutritional composition. Urine-derived fertilizers showed potential as a sustainable alternative to synthetic fertilizers.

Brittany R. Kruger, Joshua Sackett · PLoS ONE · Global

This study assessed abiotic and biotic factors affecting sweet corn production in six arid urban agricultural plots with varying shade levels (n=18 plots). Corn successfully matured in 50% of the plots. Microbial richness and diversity were high and not a hindrance. Corn success metrics positively correlated with average daytime light intensity (r=0.74-0.84) and soil organic matter (r=0.77-0.89), but negatively correlated with soil calcium, magnesium, sodium, and sulfate (r=-0.71 to -0.90).