Research & reports

Lawrence D. Harder, Ronald M. Miksha · Oecologia · Germany (Munich)

A re-analysis of the observations behind Renner et al. (2021), which had concluded that an increase in managed honey bee hives between 2019 and 2020 intensified competition with non-Apis bees in the Munich Botanic Garden, Germany. The comment shows that the change in hive numbers did not statistically alter honey bee visitation to 29 plant species either within or between years, so the shift in the proportion of non-Apis bees among visitors is better explained as a response to reduced overall floral resource availability in 2020. The claim that urban beekeeping suppresses native pollinators is therefore supported by some observational studies and contested by re-analyses that find the statistical basis insufficient.

Jonathan Stubberfield, Mads Troldborg, E. Louise Ander, N.M.J. Crout, Scott D. Young, Rupert Hough · Agronomy · United Kingdom

This study investigated the influence of gardening routines on health benefits and risks among 120 urban gardeners in the UK. Participants showed a correlation between autumn/winter gardening activity and fruit/vegetable consumption, with higher physical activity levels and lower BMI than average. However, while gardening offers health benefits, the health risks from gardening on soils mildly contaminated with cadmium and lead may outweigh these benefits, requiring formal consideration within a risk management framework.

Jorge Godoy Román · Materia Arquitectura · Germany (Berlin)

This interview with Erika Mayr, an entomologist, horticulturist, ecologist, beekeeper, gardener, writer, and caretaker, explores her over 25-year dedication to understanding the importance of bees for other species. It highlights her personal relationship with bees, particularly in Berlin's urban environment, which involved various urban spaces and communities. Now based in Rome, Mayr shares her experiences and current projects in the city.

Julia Wójcik-Madej, Barbara Sowińska-Świerkosz · Sustainability · Poland (Lublin)

A case study in Lublin city, Poland, applied objective criteria referring to seven societal challenges to 24 types of pre-existing interventions. All analyzed interventions met at least two challenges, with protecting wetlands, public parks, and allotment gardens showing the greatest challenge-orientation potential, while nesting boxes for bats and insect hotels showed the lowest. Interventions responded most to human health, climate change, and ecosystem degradation, and least to food security and socioeconomic development. The study concluded that the scale of intervention type is too general for challenge-orientation assessment.

H. Piekarska-Boniecka, Marta Rzańska-Wieczorek, Idzi Siatkowski, Tadeusz Barczak · Plant Protection Science · Poland (Poznań)

This study investigated the parasitisation of Yponomeuta malinellus feeding on Crataegus monogyna in the allotment gardens in the city of Poznań, Poland.

Demet Ülkü Gülpınar Sekban, Duygu Akyol · Journal of Urban Planning and Development · Turkey (Trabzon)

This study examined the contribution of residential gardens to ecosystem services in Trabzon City, Turkey. It was determined that both spatial needs and ecosystem benefits can be met with the same Green Infrastructure (GI) elements, and landscape value is supported by GI elements such as edible gardens, pollinator gardens, rain gardens, biological ponds, and green roofs. GI elements combining vegetation and water landscape elements have a higher potential for ecosystem services. The study concluded that green areas of residential gardens should be planned and designed through a holistic GI-oriented approach based on the total building parcel.

Grzegorz Kopij · Acta Musei Silesiae. Scientiae Naturales · Poland (Wrocław)

In 2017, a study in Wrocław, SW Poland, recorded 50 breeding bird species in an urban environment (589 ha) dominated by green habitats, including allotment gardens (41.2%). Population densities were estimated for 41 species, with high densities observed for Phoenicurus phoenicurus (9.2 pairs/100 ha) and Sylvia atricapilla (7.3). Allotment gardens showed higher densities for Pica pica (14.5) compared to Corvus cornix (6.5), and for Columba palumbus (2.8) compared to Streptopelia decaocto (1.2).

Friederike Well, Ferdinand Ludwig · Land · Germany (Munich)

A design strategy for blue-green architecture (BGA) was applied and evaluated in a practical project at a school garden in Munich, Germany. Architecture and landscape architecture students designed and implemented a BGA, building a nature-based system where school garden greywater is treated in a constructed wetland and combined with rainwater to feed a redesigned pond. This increased biodiversity, contributed to the environmental education of pupils, and demonstrated high learning success for the students.

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.

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.

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.

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.

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.

Renner S., Graf M., Hentschel Z., Krause H., Fleischmann A. · Oecologia · Germany (Munich)

Observed flower visitation on 29 plant species in a large Munich urban garden, finding that higher honeybee densities correlated with a significant shift from wild-bee to honeybee visits.

Hester Buck · Question Journal · United Kingdom (London)

This paper explores how different understandings of "community" converged during the participatory design of a moss wall at the R-urban community garden in London. The project addressed poor air quality, bringing together residents, activists, academics, and volunteers who formed a community of inquiry through meetings and workshops. The paper reflects on the successes and failures of engagement strategies, including challenges like apathy and misunderstanding.

S Black · Archaeology Data Service · United Kingdom

An archaeological evaluation was conducted for the Kalewater Community Council at Morebattle Recreation Ground, Scottish Borders, from May 24-28, 2021. This work was related to land purchased to provide community facilities, including a community garden. Five trenches, totaling 166.5 sq.m, were excavated, targeting anomalies from a September 2019 geophysics survey, but very shallow linear ditches and a possible wall/drain were found that did not appear to relate to the geophysics anomalies.

Mateusz Jackowiak, Jakub Gryz, Karolina Jasińska, Dagny Krauze‐Gryz · · Poland (Warsaw)

Density changes of red foxes and martens were investigated in the urban area of Warsaw from 2015-2021 using winter snow tracking. Results were compared with data from 1976-1978 and 2005-2008, showing a gradual increase in the average density of both mesocarnivores across all habitat types since the 1970s. A decrease in density for both species was observed in the 2017/2018 winter season, with the reasons for this decline remaining unclear.

Erik van den Elsen, P.F.A.M. Römkens, S.J.E. Verzandvoort, G.W. Korthals, Dorothee Leenders -van Tol, J. Bloem · · Netherlands (Amsterdam)

This report selects relevant soil quality indicators for assessing soil quality in the Amsterdam metropolitan region, specifically for 'urban agriculture' and 'urban green' applications. It notes that while agricultural soil quality indicators exist, specific ones for urban environments were lacking. A case study in Amsterdam's 'Fruittuinen van West' area develops an example for using these indicators in urban agriculture.

Ulrike Sturm, Tanja M. Straka, Alexandra Moormann, Monika Egerer · Insects · Germany (Berlin)

This study surveyed 111 community gardeners in Berlin and Munich, Germany, to understand the socio-psychological factors predicting pro-pollinator behavior. Using generalized linear models, the analysis revealed that gardeners who were fascinated by pollinators, held positive attitudes, and felt joy about seeing them reported intentions to protect or support pollinators. This suggests that fascination and joy can be harnessed for pollinator research and conservation efforts.

Marta Crispo, Miriam C. Dobson, Roscoe S. Blevins, William Meredith, Janice A. Lake, Jill L. Edmondson · Environmental Pollution · United Kingdom

Heavy metal (HM) and metalloid concentrations were assessed in 200 urban horticultural soils across ten UK cities. HM were found to be widespread, with most concentrations below UK soil screening values (C4SLs). However, 83% of lead (Pb) concentrations exceeded C4SLs, which is a significant concern. Bioavailable HM concentrations represented a small fraction (0.01–1.8%) of total concentrations, and black carbon (BC) and organic carbon (OC) were suggested to contribute to HM immobilization.

Emmanuelle Virey, Tolga Coskun · Cahiers ESPI2R · Europe

Green infrastructure refers to an interconnected network of natural or semi-natural areas whose proper functioning generates benefits for human societies and strengthens their resilience. It can simultaneously produce multiple benefits such as improved stormwater management, creation of cool islands and species habitats, job creation in urban agriculture, economic valuation of real estate, and new nature experiences. Green infrastructure allows for the reinvention of urban landscapes and a reconsideration of our intimate relationship with living things.