Research & reports

Gustavo Henrique [UNESP] Pereira da Silva, Margarete Cristiane de [UNESP] Costa Trindade Amorim · LA Referencia (Red Federada de Repositorios Institucionales de Publicaciones Científicas) · Brazil

A study in Florianopolis, Santa Catarina, Brazil, analyzed the effect of urban agricultural areas on atmospheric heat island intensity. Data were collected in February 2019 at 12 fixed points spanning three urban agricultural areas, eight intra-urban areas, and one area without construction materials. During daytime (9 a.m., 3 p.m.), points located to the south of the island of Santa Catarina—including urban agriculture sites—recorded the highest air temperatures, while at night temperatures decreased overall, with the studied agricultural areas becoming 'islands of freshness' relative to surrounding areas on many days.

Cristiane Veeck, Renata Menasche, Carolina Borges · AntHropológicas Visual · Brazil

A photo essay documents the relationship between hibiscus (Hibiscus sabdariffa) and humans at the Horta Comunitaria da Lomba do Pinheiro, a collective agroecological urban agriculture project in the eastern zone of Porto Alegre, Rio Grande do Sul, Brazil, begun by community initiative in 2011. Following a growing cycle that begins with sowing around August and ends with harvest between February and May, the plants trace back roughly eight years to seeds obtained from an agroecological farmer nearby; the harvest season ends with jam-making workshops, and the informal sale of dried hibiscus provides funds for maintaining the garden.

Irina PANȚIRU, Erzsébet Buta, Dănuţ Maniutiu, Alexandru I. APAHIDEAN, N. Sima, Alex Dregan, Rodica Sima · Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca Horticulture · Global

A 2022 literature review assessed the overall role and benefits of urban allotments and home gardens for urban green infrastructure (GI) in Global North countries, drawing on published evidence from 2000 onward and using narrative synthesis to interpret the research on domestic gardens and identify areas needing further study. The review found key differences in both the nature and management of urban domestic gardens with major implications for their contribution to GI sustainability, alongside heterogeneous social, cultural, ecological and economic contexts shaping that impact. It also noted that domestic gardens act as a source of food security and provide additional ecosystem services. The review concludes that home and allotment gardens are important contributors to urban GI sustainability and should be incorporated into the planning, design and management of urban infrastructure.

Judy Orton · Digital Archive @ GSU · United States

Two studies examined ecology-centered experiences — experiences with living things — among children and adolescents in the United States. Study 1 was a yearlong ethnographic study at an urban community garden in a large city in the southeastern United States, finding through participant observation and informal interviews with staff and participants that children had opportunities to learn about ecology through such experiences. Study 2 found that ecological thought — a pattern of thinking that privileges relationships between living things — did not predict environmental attitudes and behaviors, and that while ecology-centered experiences alone did predict environmental attitudes and behaviors, this predictive relationship disappeared once environmental responsibility support was taken into account.

Monika Egerer · Renewable Agriculture and Food Systems · Germany

Researchers documented Lasioglossum limbellum, a bee species not previously recorded in the Berlin, Germany region, in a community garden built on concrete slabs and planted with annual and perennial vegetation. The species nests in cavities in soft rock cliffs, a habitat that does not functionally exist in urban areas, making its presence in the garden notable; the report presents the discovery as a basis for further research on wild-bee diversity and distribution changes in urban areas.

Christopher Young, Nicole Bauer · Urban forestry & urban greening · Europe

This mixed-methods study examined the experience and effects of allotment garden loss among gardeners in Zurich, Switzerland, using field conversations with gardeners from an area slated for clearance and a natural experiment surveying the same gardener population before (2018) and after (2019) the clearance to measure effects on social networks, social support, and general and mental health. Qualitative analysis showed the (imminent) loss of the garden was a distressing experience for most participants, corroborated by descriptive survey results; ANCOVA models of the quantitative data supported a negative effect of garden loss on the number of social contacts and on emotional well-being, but not on other factors measured.

Eric J. Chapman, Gaston E. Small, Paliza Shrestha · Urban Ecosystems · Global

A study quantifying leachate and soil moisture from experimental urban garden plots receiving various soil amendments — high and low levels of manure and municipal compost, synthetic fertilizer, and no inputs — over three years. A simple mass-balance hydrologic model was parameterized for high-input municipal-compost and no-compost garden plots plus reference turfgrass plots, and run over three growing seasons under ambient precipitation and three elevated-precipitation scenarios. Soil moisture varied across treatments, with the highest mean levels in manure-compost plots and the lowest in synthetic-fertilizer plots. Soil amendment treatments explained little of the variation in weekly leachate volume, but high municipal compost and synthetic fertilizer had the lowest leachate volumes, while high and low manure compost had slightly higher volumes. Garden plots received 12-16% greater total water inputs than turfgrass plots due to irrigation, but total leachate was 20-30% lower for garden plots across climate scenarios because evapotranspiration was 50-60% higher in garden plots. Differences between high-municipal-compost and no-compost garden plots were small relative to the difference between garden plots and turfgrass overall. The study concludes that garden soil amendments influence water retention, and that the higher water retention, infiltration, and evapotranspiration potential of garden soils relative to turfgrass indicate hydrologic ecosystem services may be an underappreciated benefit of urban gardens.

Nitya Rao, Sheetal Patil, Maitreyi Koduganti, Chandni Singh, Ashwin Mahalingam, Prathijna Poonacha, Nishant Kumar Singh · · India

Despite growing interest in and recognition of urban and peri-urban agriculture (UPA) as a nature-based solution, empirical evidence on its role in reconfiguring environmental functions (biodiversity, waste management, water recycling, micro-climate regulation) and social wellbeing (food and nutrition security, gender relations, work burdens, land tenure, community ties) in India was limited. This compendium, produced by the project "Urban and peri-urban agriculture as green infrastructures" (UPAGrI), which began in 2019 to address that gap, collects 29 innovative UPA practices from cities across India, loosely grouped into four themes: environment and sustainability; food, nutrition, and livelihood; gender and subjective wellbeing; and urban policy and planning. Written mostly by practitioners themselves, the case studies document UPA innovations and serve as a repository of lessons for peer-to-peer learning among practitioners.

Emanuele Sommariva, Nicola Canessa, Giorgia Tucci · DOAJ (DOAJ: Directory of Open Access Journals) · Europe

An article links the role of ecosystem services to growing research and development funding attention to green infrastructure and urban greening strategies, positioning ecosystem services as a new parameter for assessing urban green infrastructure and re-naturalization processes that counteract climate-change effects such as flooding and heat islands while promoting conservation, resilience, and biodiversity of natural habitats. It identifies urban agriculture and community gardens as playing an important role in securing socio-ecological benefits at the local level and promoting access to healthy, "Zero Km" food sources. Drawing on the European project Creative Food Cycles, the article outlines ideas for circularity and recycling of waste across the food chain.

横浜市港北区 · 横浜市港北区 · Japan

The rooftop garden at Kohoku Ward Office in Yokohama reopened on April 1, 2022 after waterproofing and flowerbed renovation work. It is positioned as a measure against the heat island effect, for energy savings, CO2 reduction, and environmental education, with about 20 "green supporters" active Tuesdays 10am-12pm. The ward's green coverage ratio is reported to have fallen from 33.4% in fiscal 1992 to 24.1% in fiscal 2019.

Edgar Hiller, Zuzana Pilková, Lenka Filová, Martin Mihaljevič, Veronika Špirová, Ľubomír Jurkovič · Chemosphere · Slovakia (Bratislava)

A 2022 study of urban community gardens in Bratislava, Slovakia, measuring total metal(loid) concentrations in soils and in two commonly grown vegetables (tomato and lettuce), gastrointestinal bioaccessibility using a modified physiologically based extraction test (PBET), and stable lead isotopes. Although some soils would count as contaminated against Slovak agricultural-soil legislation, bioaccessibility in the intestinal phase did not exceed 20% except for cadmium, and tomatoes and lettuce contained low total and bioaccessible metal(loid) concentrations, making them safe for people eating their own produce. Lead isotope composition differed between bulk soils, vegetables and the bioaccessible fraction, with less radiogenic lead preferentially mobilised, and enrichment factors separated naturally derived elements (As, Co, Cr, Fe, Mn, Ni, V) from those with anthropogenic contributions. The result is a counterweight to blanket alarm about urban soil metals: exceeding a total-concentration threshold is not the same as a dose that reaches the human body.

Daria Ponstingel · Socio-Ecological Practice Research · United States (Austin)

A 2022 study of community gardens in Austin, Texas, USA, examining the approaches used to govern them and the socio-ecological outcomes associated with each model. Using Ostrom's socio-ecological systems framework, the author combined key-informant interviews with garden managers (yielding both qualitative and quantitative data) with remote-sensing estimates of net primary productivity — a proxy for carbon sequestration — derived from ECOSTRESS imagery on the International Space Station and Planet Inc. data. Social outcomes were measured as gardeners' satisfaction and perceived success; ecological outcomes as green-space ecosystem services. The highest social and ecological performance was found in gardens with 'bottom-up' governance structures, where community members hold decision-making and management authority. The author argues the two kinds of outcome are codependent and that the governance approach determines the form that codependence takes. The study covers gardens in a single city, so generalisation elsewhere remains to be tested.

Isabelle Anguelovski, James J. T. Connolly, Helen Cole, Melissa Garcia-Lamarca, Margarita Triguero-Mas, Francesc Baró, Nicholas Martin, David Conesa, Galia Shokry, Carmen Pérez del Pulgar, Lucia Argüelles Ramos, Austin Matheney, Elsa Gallez, Emilia Oscilowicz, Jésua López Máñez, Blanca Sarzo, Miguel Angel Beltrán, Joaquin Martinez Minaya · Nature Communications · Europe and North America (28 cities)

A 2022 test of the green gentrification hypothesis across 28 cities in 9 countries in North America and Europe, using a spatially weighted Bayesian model, in response to the limited quantitative evidence on the temporal relationship between new greenspaces and gentrification across whole cities. The study found a strong positive and relevant relationship lasting at least a decade between greening in the 1990s–2000s and gentrification occurring between 2000 and 2016 in 17 of the 28 cities — which also means no such relationship was established in the remaining 11, so greening does not invariably produce gentrification. The analysis further determines whether greening played a 'lead', 'integrated' or 'subsidiary' role in explaining gentrification. It supplies cross-city quantitative backing for the argument that new green infrastructure, including greenspace and community gardens, can create social and racial inequalities in access to the benefits of greenspace; the sample is confined to North America and Europe.

Cheng C., Aviso K.B., Tan R.R., Aviso K. · Sustainability (MDPI), 13(16):9042 · Asia

A study developing a system-dynamics model of a rooftop farm in Taipei City to analyze the socio-environmental benefits of rooftop agriculture (improved food access, community ties, energy savings, reduced flood risk). It frames rooftop farming as a practical solution for strengthening water-energy-food nexus synergies in greener cities.

Begum M.S., Bala S.K., Islam A.K.M.S., Roy D. · Sustainability (MDPI), 13(16):9053 · Asia

Compares an experimental agricultural rooftop with bare roofs, measuring microclimate parameters including air, surface, and indoor temperature, humidity, and carbon dioxide. It shows that rooftop agriculture can mitigate urban microclimate change and supply fresh vegetables while delivering environmental and socioeconomic benefits to city dwellers.

Artmann M., Sartison K. · Making Green Cities: Concepts, Challenges and Practice (Springer, Cities and Nature series), 173-194 · Global

A case study analyzing the 'Edible City' of Andernach, Germany, as a multifunctional productive green space where citizens can harvest freely in public areas. Drawing on interviews with key initiators, it shows that the project generates multifunctional social, ecological and economic benefits addressing urban challenges such as food security, biodiversity and social cohesion, and examines its potential for upscaling local food supply.

Scarano A., Semeraro T., Chieppa M., Santino A. · Horticulturae · Italy

Review of neglected and underutilized plant species from the Apulia region of southern Italy, highlighting their adaptive, nutritional, and economic potential and the case for re-including them in the daily diet.

Ferrer Valverde M.A., Sánchez-Palomo E., Osorio Alises M., Chaya Romero C., González-Viñas M.A. · Foods 10(8):1683 · Spain

Characterized the traditional Trujillo melon from La Mancha, Spain, over three harvests, identifying 55 volatile compounds. Sensory profile featured jam, cucumber, sweet, and honey aromas, documenting quality of a regional heirloom melon.

Rosa-Martínez E., Adalid A.M., Alvarado L.E., Burguet R., García-Martínez M.D., Pereira-Dias L., Casanova C., Soler E., Figàs M.R., Plazas M., Prohens J., Soler S. · Frontiers in Plant Science 12:633957 · Spain

Evaluated 44 Mediterranean 'de penjar' long shelf-life tomato varieties under two nitrogen levels. Local varieties exceeded commercial ones in sweetness-to-acidity ratio and vitamin C, with lycopene varying over four-fold, supporting low-input breeding.

Martínez-Ispizua E., Martínez-Cuenca M.-R., Marsal J.I., Díez M.J., Soler S., Valcárcel J.V., Calatayud Á. · Molecules 26(4):1031 · Spain

Evaluated bioactive compounds and antioxidant capacity of Valencian pepper landraces relative to commercial types. Landraces displayed rich diversity in nutritional and functional compounds, reinforcing the value of regional Capsicum genetic resources.

Shao H., Hill R., Xue D., Yang J. · Journal of Ethnobiology and Ethnomedicine 17: Article 56 · China

Documents how Wa ethnic homegardens in Yunnan harbor traditional vegetable germplasm diversity through local culture, traditional knowledge, and seed conservation and sharing systems that maintain in situ agrobiodiversity.

Guzzon F., Arandia Rios L.W., Caviedes Cepeda G.M., Céspedes Polo M., Chavez Cabrera A., Muriel Figueroa J., Medina Hoyos A.E., Jara Calvo T.W., Molnar T.L., Narro León L.A. · Agronomy 11(1):172 · Latin America

Reviews the fundamental role of Latin American maize landraces for food security, livelihoods and culture, the threat of genetic erosion, and the current state of their conservation and use.

中川 睦司, 高橋 秀和, 上田 健治, 渡辺 明夫, 赤木 宏守, 櫻井 健二 · 園芸学研究（Hort. Res. (Japan)）, 20(4): 379-385 · Japan

Using SSR markers on four Akita native eggplant varieties and 46 domestic landraces, phylogenetic and population structure analyses inferred the genetic relationships and likely introduction routes of traditional Akita eggplant cultivars.

Ludwig B. · Sustainability (MDPI) · Germany

Analyzes the significance of green-space design in early modernist housing estates (1919–1927) in then-German Lower Silesia, addressing urban layout, public/private greenery systems including gardens, and protection of valued trees from natural, landscape, and social perspectives.

Dorr, E., Goldstein, B., Horvath, A., Aubry, C., Gabrielle, B. · Environmental Research Letters 16, 093002 · Global

A systematic review and meta-analysis (53 studies) of urban agriculture's environmental impacts and resource use, quantitatively showing that effects vary widely by farm form, scale and technology, and evaluating life-cycle assessment against rural farming.