Research & reports

Shahida Mohd Sharif, Izyan Ayuni Mohamad Selamat, Norsidah Ujang · Springer Link (Chiba Institute of Technology) · Malaysia

This study used a hermeneutic phenomenological approach supported by field observations to examine the lived experiences of long-term gardeners at the PPR Intan Baiduri public housing estate in Kuala Lumpur, Malaysia, exploring how grassroots gardening supports resilience, health and informal governance. It found that gardening provides retirees and low-income residents with routine, emotional wellbeing and opportunities for informal economic participation, that community gardens function as micro-level bioresource systems by repurposing reserve land, composting household waste and drawing on institutional collaborations with agencies such as DBKL and TNB, and that participants collectively organize planting cycles and maintain shared infrastructure while navigating labor constraints and fluctuating participation.

Veronika Hansen, Franziska Häfner, Bianca Messmer, Luca Bragazza, Carsten Tilbæk Petersen, Jakob Magid · Agriculture Ecosystems & Environment · Europe

Using a long-term field trial (the CRUCIAL experiment) running for more than 20 years in Denmark, this study compared the long-term effects of bio-based fertilizers (BBFs) — compost, sewage sludge, cattle slurry, and human urine — against conventional mineral NPK fertilizer on soil physical, chemical, and biological properties. Mineral NPK fertilizer supported crop productivity and improved certain soil properties but did not deliver the broader soil health benefits of organic amendments; compost and sewage sludge notably increased soil organic carbon, cation exchange capacity, porosity, water content at field capacity, and microbial activity while reducing bulk density and clay dispersibility. Human urine produced a nitrogen fertilizer effect on crop yield comparable to NPK, but showed a higher sodium adsorption ratio than NPK and a negative trend in bulk density (though values stayed below critical thresholds), indicating a need for complementary organic matter input, and carbon-rich bio-based fertilizers reduced crop production per unit of nitrogen applied.

Bharti Gautam, Neha Negi, J. Mohan, Babita Bharti, Amit Kumar, Ridhima Arya · International Journal of Advanced Biochemistry Research · Global

A review paper surveying sustainable urban agriculture and gardening practices against a backdrop of rapid urbanization linked to climate change, biodiversity loss, and environmental degradation. It covers composting, rainwater harvesting, rooftop gardening, hydroponics, aquaponics, and vertical farming, and discusses the role of integrated pest management, smart irrigation systems, and urban agroforestry. The review states that integrating nature-based solutions — urban farms, vertical gardens, and green roofs — into the urban landscape can lessen environmental problems such as poor air quality, flooding, and the urban heat island effect, and that urban horticulture plays an important role in food security, biodiversity, and environmental sustainability.

Made Dwi Kanaka Sarahswati, Dew Ayu Trisna Adhiswari Wedagama · Penamas Journal of Community Service · Indonesia

A community service program in Dauh Puri Kaja Village, Denpasar, Indonesia (2025) combined urban farming with 3R-based waste management (reduce, reuse, recycle), providing hands-on training at the local Balai Banjar in waste sorting and composting organic waste for use in urban farming, followed by compost distribution at the village's waste management site. Reported outcomes were improved community understanding of using compost for household-scale farming and of proper waste segregation; the program's anticipated longer-term community impact was stated as an expectation, not a measured result.

ER Ramesh Chand, Ridhima Arya, Ravi Pratap Singh, Devi Singh, Vedant Singh · International Journal of Advanced Biochemistry Research · Global

A review article surveys evidence on rooftop vegetable farming's ability to absorb carbon and noise, lower air temperatures on and around roofs, and reduce urban heat-island effects, alongside using composted kitchen waste as a substitute for mineral fertilizers. It cites prior research showing compost can raise soil moisture content, decrease soil erosion, and help manage pests, weeds, and diseases, in place of mineral insecticides and fertilizers currently used in some urban rooftop gardens. The review notes rooftop gardening is a relatively new concept in Bangladesh and is intended to support further study of the practice there.

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.

Javier Bayo, Joaquín López-Castellanos, Marta Doval-Miñarro, Sonia Olmos · Scientific Reports · Spain

An ATR-FTIR analysis of 11 commercial compost products found microplastics in every sample, averaging 137.65 ± 6.01 items/kg dry weight and up to 631.14 mg/kg. Eco-labeled composts had significantly lower microplastic abundance, size, and concentration than non-eco products. Microplastic concentration correlated negatively with pH and nitrogen content and positively with organic matter content.

US Environmental Protection Agency (EPA) · US Environmental Protection Agency (EPA) · United States

An EPA summary of its 2024 survey of anaerobic digestion facilities processing food waste in the U.S., covering 313 identified facilities with 65 operating facilities responding (24% response rate). Excluding beverage-industry waste, processed tonnage rose from about 1.36 million tons in 2022 to about 1.43 million tons in 2023.

環境省 · 環境省 環境再生・資源循環局 廃棄物適正処理推進課 · Japan

Japan's Ministry of the Environment statistical compendium on FY2023 municipal solid waste management. The national waste-flow chart shows total waste generation of 38,974 thousand tonnes and total recycled volume of 7,633 thousand tonnes (recycling rate 19.5%). Of the 6,234 thousand tonnes recycled by municipalities, 119 thousand tonnes (1.9%) went to fertilizer and 6 thousand tonnes (0.1%) to animal feed.

ADEME · ADEME Infos · France

One year after France's January 2024 mandate for source-separated food waste, ADEME reports that about 50% of residents (32.1 million people) now have access to municipal sorting services, 56% sort their food waste, and 9 million tonnes of biowaste per year have been diverted from incineration and landfill, backed by €100 million in green-fund investment since 2023.

Anne Lenormand · Banque des Territoires (Localtis) · France

Reporting that France's source-separation infrastructure for biowaste has tripled in three years since the January 2024 legal mandate, giving 32.1 million French residents (about 50%) access to sorting solutions (municipal collection, individual and shared composting). The rollout had a difficult start but is now accelerating, with 20 million more residents expected to gain access.

Jacob Wallace · Waste Dive · United States

NYC's Department of Sanitation began enforcing mandatory curbside organics separation on April 1, 2025, issuing nearly 2,000 summonses in the first week, but Mayor Adams paused broad enforcement through 2025 on April 18, limiting fines to persistent violators. The city had distributed about 190,000 free bins and sold 63,000 more, and organics diversion had risen 65% from FY2022 to FY2024.

US Environmental Protection Agency · U.S. Environmental Protection Agency (EPA) · United States

U.S. municipal solid waste (MSW) generation reached 292.4 million tons in 2018. The landfilling rate fell from 94 percent in 1960 to 50 percent in 2018, while the combined recycling and composting rate rose from just over 6 percent in 1960 to 32.1 percent in 2018, including 25 million tons composted and 69 million tons recycled.

U.S. Environmental Protection Agency · US EPA Landfill Methane Outreach Program (LMOP) · United States

According to US EPA's LMOP page, landfill gas is roughly 50% methane and 50% CO2, and methane is at least 28 times more effective than CO2 at trapping heat over 100 years. Municipal solid waste landfills are the third-largest source of human-related methane emissions in the US, accounting for about 14.4%. There are 542 operational LFG energy projects nationwide, about 63% generating electricity and about 20% producing renewable natural gas.

· Wikipedia (italiano) · Italy

An Italian Wikipedia article on marcite, a traditional Lombard irrigated-meadow technique combining supply and drainage channels on gently and evenly sloped land to keep grass growing through winter under a thin flowing water layer. While ordinary meadows are cut 4-5 times a year, marcite could be harvested 7 or more times, often 9, with the third cutting in late May (maggengo) alone accounting for roughly 25% of annual yield. Origins are uncertain, though Cistercian monks from France are credited with spreading the technique in northern Italy; it was largely replaced by maize cultivation in the 20th century, and today 41 marcite are protected within Parco Agricolo Sud Milano.

Amato-Lourenço L.F., Franca G.C., Seckler M.M., Mauad T. · Environmental Challenges, 14:100864 · Brazil

An analysis of a resident-led, decentralized community composting initiative begun in 2018 in São Paulo, using thermophilic decomposition (the UFSC method) in public squares. It presents a civil-society-driven waste-management model with positive environmental and social outcomes.

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.

Maeve Malone, Kabindra M. Shakya · Sustainability · United States

This paper reviews the state of heavy metal contamination (such as lead, arsenic, and cadmium) in community garden soils across the United States, noting that gardeners are exposed through pathways such as inhalation and ingestion. It states that contamination hot spots are higher in city areas with greater minority populations and lower incomes. The review outlines mitigation approaches including applying biochar and compost, using raised beds, and maintaining a natural pH.

Carolyn A. Zeiner, Maria N. Kisch, Ethan D. Lynch, Paliza Shrestha, Gaston E. Small · Urban Agriculture & Regional Food Systems · United States (Minnesota)

This study characterized soil microbial activity profiles—microbial abundance, soil respiration, extracellular enzyme activity, and crop yield—in an urban agriculture system in Minnesota, USA, using recycled organic compost (manure or municipal) at high or low rates. A high application rate of manure compost supported 6–10× higher basal respiration, and microbial biochemical function predicted 50% of the variability in bell pepper yield while community size alone was a poor predictor, indicating that "more is better" does not necessarily hold for soil microbial health.

· Agronomy · Global

Assesses the reproducibility of the composting process and the quality of composts obtained under a decentralized municipal solid waste composting scenario.

· Discover Animals · Global

Selects and evaluates the optimal medium for the earthworm Eisenia fetida in sustainable waste recycling.

· Frontiers in Sustainable Food Systems · South America

Study examining the use of urban food waste compost in urban agriculture in Rosario, Argentina. Analyzes waste-to-resource conversion and organic cycling potential.

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.

Yang et al. · GeoHealth · United States (Massachusetts)

Decadal study of Boston's municipal composting program. Lead concentrations consistently exceeded EPA soil benchmarks. Program halted in 2012. Highlights importance of compost safety for urban agriculture.

Boston University School of Public Health · Boston University School of Public Health · United States

Examines historical inequities in urban organic waste and composting access. Highlights disparities in low-income and communities of color. Advocates for equitable policy design and implementation.