Estimating stormwater runoff for community gardens in New York City

Community gardens are critical ecological infrastructure in cities providing an important link between people and urban nature. The documented benefits of community gardens include food production, recreational opportunities, and a wide number of social benefits such as improving community stability, reducing crime, and physical and mental health benefits. While much of the literature cites community gardens as providing environmental benefits for cities, there is little empirical evidence of these benefits. Here we examine the stormwater runoff benefits of community gardens by comparing two methods to estimate absorption rates of stormwater runoff in urban community gardens of New York City. The first method uses general land cover classes as determined by a land cover dataset; the second methods adds a land cover specific to community gardens — raised beds, typically used for food production. We find that in addition to the stormwater mitigation performed by pervious surfaces within a garden site, community gardens in New York City may be retaining an additional 12 million gallons (~45 million liters) of stormwater annually due to the widespread use of raised beds with compost as a soil amendment.     

Local and landscape drivers of arthropod abundance,richness, and trophic composition in urban habitats

Urban green spaces, such as forest fragments, vacant lots, and community gardens, are increasingly highlighted as biodiversity refuges and are of growing interest to conservation. At the same time, the burgeoning urban garden movement partially seeks to ameliorate problems of food security. Arthropods link these two issues (conservation and food security) given their abundance, diversity, and role as providers of ecosystem services like pollination and pest control. Many previous studies of urban arthropods focused on a single taxon (e.g. order or family), and examined either local habitat drivers or effects of landscape characteristics. In contrast, we examined both local and landscape drivers of community patterns, and examined differences in abundance, richness, and trophic structure of arthropod communities in urban forest fragments, vacant lots, and community gardens. We sampled ground-foraging arthropods, collected data on 24 local habitat features (e.g., vegetation, ground cover, concrete), and examined land-cover types within 2 km of 12 study sites in Toledo, Ohio. We found that abundance and richness of urban arthropods differed by habitat type and that richness of ants and spiders, in particular, varied among lots, gardens, and forests. Several local and landscape factors correlated with changes in abundance, richness, and trophic composition of arthropods, and different factors were important for specific arthropod groups. Overwhelmingly, local factors were the predominant (80 % of interactions) driver of arthropods in this urban environment. These results indicate that park managers and gardeners alike may be able to manage forests and gardens to promote biodiversity of desired organisms and potentially improve ecosystem services within the urban landscape.     

Herbivores and natural enemies of brassica crops in urban agriculture

Urban agriculture has been growing in popularity around the globe. As more land is allocated to urban agriculture, there is a greater need to understand arthropod herbivores and natural enemies in these sites. The area and production type of urban agriculture could influence the risk of pest outbreaks, since larger food production areas are hypothesized to host more abundant herbivore populations. To determine the potential for pest outbreaks, we sampled for pests and above-ground natural enemies at three types of sites with variable amounts of cultivated areas: residential gardens, community gardens, and urban farms. We focused on pests of brassica, a widely cultivated crop family attacked by cabbageworms and aphids. We investigated the relationships of garden characteristics and surrounding land cover on natural enemies and herbivores of brassica. More herbivores and plant damage were expected in larger community gardens and urban farms. However, herbivore populations were low across sites and not explained by garden characteristics or area of production. Herbivory on brassica averaged less than 15% at all sites. Limited plant damage and low herbivore numbers may be attributed to the positive effects of garden flowers on parasitoids and high numbers of parasitoids and generalist predators across sites. Garden area and floral resources had positive relationships with natural enemy abundance, although community composition was similar across sites. Since arthropod natural enemies were abundant across all types of food production, this suggests that urban agriculture is a beneficial habitat that could support regulating ecosystem services such as biological control.     

Native plants are the bee’s knees: local and landscape predictors of bee richness and abundance in backyard gardens

Urban gardens may support bees by providing resources in otherwise resource-poor environments. However, it is unclear whether urban, backyard gardens with native plants will support more bees than gardens without native plants. We examined backyard gardens in northwestern Ohio to ask: 1) Does bee diversity, abundance, and community composition differ in backyard gardens with and without native plants? 2) What characteristics of backyard gardens and land cover in the surrounding landscape correlate with changes in the bee community? 3) Do bees in backyard gardens respond more strongly to local or landscape factors? We sampled bees with pan trapping, netting, and direct observation. We examined vegetation characteristics and land cover in 500 m, 1 km, and 2 km buffers surrounding each garden. Abundance of all bees, native bees, and cavity-nesting bees (but not ground-nesting bees) was greater in native plant gardens but only richness of cavity-nesting bees differed in gardens with and without native plants. Bee community composition differed in gardens with and without native plants. Overall, bee richness and abundance were positively correlated with local characteristics of backyard gardens, such as increased floral abundance, taller vegetation, more cover by woody plants, less cover by grass, and larger vegetable gardens. Differences in the amount of forest, open space, and wetlands surrounding gardens influenced abundance of cavity- and ground-nesting bees, but at different spatial scales. Thus, presence of native plants, and local and landscape characteristics might play important roles in maintaining bee diversity within urban areas.     

Determinates of inner city butterfly and bee species richness

Although urbanization is increasing worldwide, relatively few studies have investigated patterns of urban biodiversity outside of city parks and reserves, in urban neighborhoods where people live and work. We evaluated models including local and landscape factors that might influence the bee and butterfly richness of community gardens located within densely populated neighborhoods of the Bronx and East Harlem in New York City (>10,000 people/km²). The gardens were surrounded by buildings and limited amounts of green space (3,600–17,400 building units and 10–32% green space within a 500 m radius). Contrary to our initial prediction that landscape green space might be especially influential in this heavily urbanized setting, the most highly supported models for both bee and butterfly richness (based on Akaike Information Criterion) included just the local, within-garden variables of garden floral area and sunlight availability. There was marginal support for models of bee richness including the number of building units surrounding gardens within a 500 m radius (which exhibited a negative association with bee richness). In addition, perhaps because bees are central place foragers that may nest within or near gardens, supported models of bee species richness also included total garden area, canopy cover, and the presence of wild/unmanaged area in the garden. Generally, our findings indicate that sunlight and floral abundance are the major factors limiting local pollinator diversity in this setting. This suggests that rooftop and other “open” urban habitats might be managed to increase local pollinator diversity, even if seemingly “isolated” within heavily developed neighborhoods.     

A three-city comparison of drug use and drug use before sex among young men who have sex with men in the United States

High rates of drug use have been documented among young men who have sex with men (YMSM). However, updated prevalence data are needed to understand current trends, especially for drug use before sex. We used baseline data from an HIV prevention trial to examine demographic differences in drug use and drug use before sex among YMSM in Atlanta, Chicago, and New York City. Marijuana was the most commonly used drug, but alkyl nitrites (“poppers”), cocaine, and Ecstasy were also commonly used. Drug use was more prevalent among older and White YMSM, and it was similar across cities, although use of poppers and polydrug use were more common in New York City. Our data generally support national prevention efforts.     

Floral biodiversity of allotment gardens and its contribution to urban green infrastructure

Allotment gardens are a key feature of the urban landscape, providing numerous benefits beyond those of food production. These include ecosystem services such as local climate modification, pollination, and providing a pleasant location for socialising. The biodiversity of flora underpins many of these ecosystem services. The aims of this study are to assess the spontaneous vascular flora of urban allotment gardens and derive estimates of the species richness and diversity. In doing so, the specific position of allotment gardens within urban green infrastructure will be revealed and the role of allotment users in shaping local biodiversity determined. 358 species of spontaneous flora were recorded in 11 representative allotment garden estates (total area 150 ha) in Poznań, Poland. Fourteen biodiversity features were taken into account. The investigated areas exhibited high plant species richness, high diversity, low synanthropisation level, and contained valuable geobotanical elements, including plants of key importance for the European Community. For these reasons, allotment gardens should be considered as biodiversity hotspots for native species within urban green infrastructure. Based on an analysis of the spatial and functional organization of 110 individual plots, four types of usage, and corresponding plant diversity have been distinguished. The composition of the flora depends mostly on spatial and functional organization of allotment gardens and, to a much lesser extent, on the habitat conditions, which on individual plots varied very little. The high species richness and diversity in allotment gardens has important consequences for urban planning.     

Mammal conservation in a changing world: can urban gardens play a role?

Urbanisation threatens biodiversity globally, yet some animal populations persist within urban landscapes. Conservation of urban wildlife has prioritised parks and remnant bushland as critical habitat and neglected the role that residential gardens offer for conservation. We explored the potential for residential gardens to assist the conservation of mammals using an online questionnaire administered to residents of two case study cities in Australia to identify how widespread mammals in cities can be, which garden features promote mammal presence, and if the features varied among species with different habitat requirements. From 649 responses we found that three mammal species with different habitat requirements occurred in residential gardens throughout the city landscape. Garden features promoting mammal presence were consistent with broad ecological and habitat requirements of each species, but differed among both species and regions. Our study demonstrates that residential gardens offer a valuable habitat for mammals, and that garden features could be manipulated to promote use of gardens by these species. By considering gardens in urban planning and management actions aimed at conserving urban wildlife, residential gardens offer additional habitat to parks, roadside vegetation and urban bushland, and can play a significant role in biodiversity conservation.

     

Visions of Public Space: Reproducing and Resisting Social Hierarchies in a Community Garden

Urban public spaces are sites of struggles over gentrification. In increasingly diverse cities, these public spaces also host interactions among people of different class, race, ethnicity, and immigration status. How do people share public spaces in contexts of diversity and gentrification? I analyze the conflicting ways of imagining shared spaces by drawing on an ethnographic study of a community garden in a diverse and gentrifying neighborhood in New York City, conducted between 2011 and 2013. I examine how conflicts among gardeners about the aesthetics of the garden and norms of conduct reproduce larger gentrification struggles over culture and resources. Those who wanted the garden to be a lush and orderly space drew on their privilege and resources to leverage support from institutional actors and push through a vision that resonated with aesthetic preferences of affluent residents and developers. At the same time, I found that the diversity, combined with several other characteristics, created openings for cultural disruption. Utilizing relationships built across dramatic lines of class, race, and immigration difference, less privileged gardeners were able to destabilize hierarchies and defend their visions of this public space. Conflict and messy deliberation—rather than harmonious community—facilitated engagement with difference.     

An assessment of soil nematode food webs and nutrient pools in community gardens and vacant lots in two post-industrial American cities

In the midst of the current economic crisis, there is renewed interest in transforming vacant lots into food-producing gardens. This study analyzed whether vacant lots are suitable for food production, by comparing the soil nematode food webs and nutrient pools of vacant lots and community gardens in two post-industrial U.S. cities, Akron and Cleveland, Ohio. Twelve vacant lots and 12 community gardens were examined in the two cities. All six Akron community gardens were established just prior to the initiation of this study, whereas the six in Cleveland were 15–30 years old. Soil pH, texture, moisture, organic matter, mineral nitrogen content, microbial biomass, and nematode communities were measured in both cities. Soil decomposition rate was also measured in Cleveland. Results show that the soils of vacant lots surpassed those of the newly-established Akron gardens and were equal to the soils of the well-established Cleveland gardens in the amount of ammonium-nitrogen, total nematode population, genus diversity, and maturity and structure indices. The soils of the vacant lots were lower than the community gardens in the amounts of soil moisture, organic matter, and nitrate-nitrogen, which we associate with the addition of water, compost, fertilizer, and tilling in the gardens. No significant difference was found between community gardens and vacant lots in microbial biomass, decomposition rate, or nematode enrichment index, which seems to indicate that vacant lots are equal to community gardens in nutrient availability and nutrient cycling. We conclude that barring any contamination, the soil in vacant lots maybe suitable for the establishment of food gardens, which can provide many desirable ecosystem services and enhance human well-being. We also find that the disturbance associated with tillage and conversion of a vacant lot into a community garden has short-term ramifications for both nematode food webs and mineral-nitrogen content.     

Agroecological and social characteristics of New York city community gardens: contributions to urban food security,ecosystem services,and environmental education

There is growing public interest and participation in food-producing urban community gardens in North America, yet little research has examined agricultural production and ecological processes in these spaces. We describe the agroecological and social characteristics of 61 food-producing gardens in New York City, drawing on gardener interviews, land-use maps, plant species inventories, arthropod scouting, and soil sampling and analysis. Gardens contained agricultural crops, food production infrastructure, ornamental plants, and recreational areas in varying proportions, indicating that gardens serve multiple and distinct purposes depending on community needs and interests. On average, gardeners devoted the greatest proportion of garden area (44 %) to food production, and supplied a large share of their households’ produce needs from their community gardens. Solanaceae, Brassicaceae, and Cucurbitaceae crops dominated food crop areas, hindering effective crop rotation to prevent disease and pest problems. Most gardeners grew crops in raised beds constructed with clean fill and compost. These soils generally had sandy textures, low water-holding capacity, high organic matter levels (with a large proportion from recent inputs) and excessive nutrient levels. Soil water content at field capacity increased exponentially with total soil carbon, suggesting that organic matter enhances water-holding capacity. Insect pest densities greatly exceeded action thresholds in nearly all gardens for aphids and whiteflies on Brassica crops, aphids on Cucurbit crops, and two-spotted spider mites on tomatoes. Predator and parasitoid densities were generally low (less than one per plant on average), perhaps partially due to low floral and woody perennial cover in most gardens (12 % and 9 % on average, respectively). Dominant groups of natural enemies were minute pirate bugs, spiders, and parasitoid wasps. A wide variety of people of differing experience levels, incomes, and ethnicities participate in community gardening in NYC, and most gardens host multiple languages. Promising directions for urban gardening research, education, and practice include: 1) Cover cropping to improve soil quality and nutrient management, and diversify crop rotations; 2) Improving access to soil testing and guidance on appropriate use of soil amendments, 3) Enhancing habitat for arthropod natural enemies that provide biological control of insect pests with floral and woody perennial plantings; and 4) Incorporating ecological knowledge and inquiry-based approaches into gardening workshops, educational materials, and technical support, and offering these resources in multiple languages.     

Drivers of plant biodiversity and ecosystem service production in home gardens across the Beijing Municipality of China

Home gardens have been recognized as repositories of agricultural biodiversity across the world. The influence of socioeconomics and location-specific factors on urban gardening patterns merits continued study. Using Beijing Municipal Province in China, a rapidly urbanizing region, as a case study, we address two questions: 1) How do biodiversity patterns change between different urbanized regions in Beijing? 2) How do ecosystem services provided by Beijing home gardens change with socioeconomic status and location-based preferences of gardeners? We surveyed 104 home gardens in Beijing Municipal Province for plant biodiversity, abundance, and species ecosystem services (ES) (provisioning or cultural uses). The gardens were distributed across three urbanized regions (suburban, peri-urban, and exurban). We found that species biodiversity and abundance shift according to a hierarchy of need from ornamentals (cultural ES) to edibles (provisioning ES) with increasing distance from Beijing. These trends are related to reduced income, lowered food security, and lack of urban markets in exurban regions. Rarefaction curves indicate ornamental species drive β diversity. Ordination also showed a shift in species composition with increasing isolation from the city; Suburban and exurban gardens were the most different, while peri-urban gardens were similar to both others. Only exurban gardens had a positive relationship between species and area. High edible cover and high species density indicates that demand for edibles in exurban regions may be higher than space constraints allows. Our study better quantifies species biodiversity patterns in Beijing, and can inform urban planners about the value and usefulness of home garden space.     

Visions of resilience: lessons from applying a digital democracy tool in New York’s Jamaica Bay watershed

Resilience to extreme weather events and other sudden changes is an issue facing many communities in the early twenty-first century. Planning to respond to disasters is particularly complicated in densely inhabited, multi-jurisdictional urban social-ecological systems like the watershed of Jamaica Bay, a large urbanized estuary on the south side of New York City. This area contains parklands managed by New York City, the National Park Service, and other agencies, four sewage treatment plants, three former landfills, and urban and suburban communities, all of which were heavily impacted by Hurricane Sandy in 2012. Here successful resilience planning and response requires participation from a wide variety of government and civil society players each with different types of knowledge, value systems, and expectations about what resilience means. To investigate how “visions” of future resilience differed among several communities living in or concerned with Jamaica Bay, New York, we deployed a free, Internet-based modeling framework called Visionmaker that enabled interactive scenario creation and testing. Through a series of standardized workshops, we recruited participants from a variety of different communities of practice (i.e. researchers, land managers, educators, non-governmental organization staff, and community board members) to design “visions of resilience”. Visions spanned terrestrial and marine environments and contained natural and built ecosystems. Most users favored increasing resilience through expanding salt marsh and green infrastructure while, for the most part, keeping the built city landscape of streets and buildings intact. We compare and contrast these visions and discuss the implications for future resilience planning in coastal cities.

     

Spatial configurations of urban forest in different landscape and socio-political contexts: identifying patterns for green infrastructure planning

Rapid urbanisation and climate change have motivated the development of urban green infrastructure (UGI) as a planning strategy to support the wellbeing of urban people and ecosystems while parallel adapting cities to climate change. Forest (tree-covered areas >0.5 ha) is a key UGI component that afford a wider range of ecosystem services and mitigate urban heat islands more effectively than non-wooded green spaces. However, understanding of spatial configurations (variation in patch size and frequency) of forests across the gradient of urbanisation and between cities is limited to case studies. This represents a considerable knowledge gap for identification of general patterns that can inform integration of forest resources in UGI planning that have value beyond the individual city level. In this study we used Geographic Information Systems to explore the spatial configuration of forests across cities located within landscapes characterised by different levels of anthropogenic modification (degree of forest cover) and socio-political contexts, i.e. all Danish and Swedish cities >10,000 inhabitants (n = 176). We applied general linear modelling to investigate the relationship between forest cover, patch size and frequency with 1) regional landscape type, 2) demographic trends 1960–2010, and 3) the gradient of urbanisation (measured in three zones: urban core (0.2 km from city boundary), urban fringe (0.2–2 km), and urban periphery (2–5 km)). Regardless of demographic trends, forest cover was lowest in cities settled in large-scale agricultural regions, higher in regions with mosaics of forest and farming, and highest in forest-dominated regions. However, in all cities forest cover was lowest in the urban zone and peaked on the urban fringe rather than on the urban periphery. Furthermore, pocket woods (0.5–2 ha) accounted for over 50 % of patches in all three urban zones, irrespective of regional landscape type. We conclude by discussing how these general patterns could inform strategies for integration of urban forests in UGI planning.     

City dwelling wild bees: how communal gardens promote species richness

Urban areas consist of wide expanses of impervious surfaces which are known to negatively affect insect biodiversity in general, but green spaces within cities have the potential to provide necessary habitat and foraging resources. Although, communal gardens were primarily intended to provide fresh, regional food to denizens, these green islands also host a surprisingly high number of wild bee species.

The gardens were characterized based on structural elements such as flower frequency, the relative percentage of lawn, trees, shrubs, planted crops and infrastructure (e.g. seating possibilities or garden houses). Further, the effects of different landscape structures surrounding the gardens and distance to the city center were analyzed on the total wild bee species richness and functional traits. Focusing on these putative influencing factors, statistical analyses calculating random decision forests along with generalized linear mixed models were applied. With 113 observed wild bee species, communal gardens provide habitat for a quarter of all known species in Vienna. In conclusion, results revealed that only elements within the gardens had an effect on species richness, with flower frequency as the major positive driver. The examined communal gardens promote and conserve wild bees independent from the location within the city or garden size. Furthermore, these green patches are important sanctuaries, hosting rare and threatened species as well as remarkably special wild bee communities.

     

Ecosystem services in managing residential landscapes: priorities,value dimensions,and cross-regional patterns

Although ecosystem services have been intensively examined in certain domains (e.g., forests and wetlands), little research has assessed ecosystem services for the most dominant landscape type in urban ecosystems—namely, residential yards. In this paper, we report findings of a cross-site survey of homeowners in six U.S. cities to 1) examine how residents subjectively value various ecosystem services, 2) explore distinctive dimensions of those values, and 3) test the urban homogenization hypothesis. This hypothesis posits that urbanization leads to similarities in the social-ecological dynamics across cities in diverse biomes. By extension, the thesis suggests that residents’ ecosystem service priorities for residential landscapes will be similar regardless of whether residents live in the humid East or the arid West, or the warm South or the cold North. Results underscored that cultural services were of utmost importance, particularly anthropocentric values including aesthetics, low-maintenance, and personal enjoyment. Using factor analyses, distinctive dimensions of residents’ values were found to partially align with the Millennium Ecosystem Assessment’s categories (provisioning, regulating, supporting, and cultural). Finally, residents’ ecosystem service priorities exhibited significant homogenization across regions. In particular, the traditional lawn aesthetic (neat, green, weed-free yards) was similarly important across residents of diverse U.S. cities. Only a few exceptions were found across different environmental and social contexts; for example, cooling effects were more important in the warm South, where residents also valued aesthetics more than those in the North, where low-maintenance yards were a greater priority.     

Attack of the Butterfly Spirits: The Impact of Movement Framing by Community Garden Preservation Activists

This study of the community garden preservation movement on the Lower East Side of New York examines the role of movement framing by activists in their struggle to save hundreds of gardens from destruction. In repeated confrontations with the Giuliani administration, gardeners successfully de-routinized the process of urban redevelopment by portraying the loss of a garden as an unimaginable violation against themselves, and the city. This process of re-framing urban development helped activists to compensate for their disempowered political status, and was instrumental in forcing the Giuliani administration to negotiate to save the gardens. Focusing on framing by movement activists demonstrates the purposive and strategic character of neighborhood identity. Emphasizing the strategy of neighborhood identities is a useful corrective to the many studies of community movements that emphasize their emergence from a relational, presumably non-strategic, local reality.     

The Children's Aid Society community schools: a full-service partnership model

In 1989, the Children's Aid Society (CAS) created an unprecedented partnership with the New York City Board of Education by developing a comprehensive response to the pressing needs of children and families in the northern Manhattan neighborhood of Washington Heights. After three years of careful planning, CAS and the New York City public schools opened the first community school at Intermediate School 218, offering a full array of supports, services, and learning opportunities. Adding, on average, one partnership school per year and remaining very flexible in adapting its model to the individual needs of each community, CAS now has thirteen community schools around New York City. The model's flexibility is seen also in the success of its national and international adaptation-an intentional part of CAS's work.     

Exploring racial and ethnic differences in recreational drug use among gay and bisexual men in New York city and Los Angeles

Reported rates of recreational drug use among gay and bisexual men are currently rising. Although there has been much empirical research documenting current trends in drug use among gay and bisexual men, little research has empirically contrasted differential rates across urban epicenters, while even less has addressed racial or ethnic variation (between and within cities). This knowledge is essential both for the development of effective culturally-sensitive health education prevention/services and for understanding drug use prevalence among urban epicenters. Using the men's data gathered from large-scale gay, lesbian, and bisexual (GLB) community events in New York and Los Angeles in the fall of 2003 and spring of 2004 (N = 2,335), this study explored racial and ethnic variance in the use of methamphetamine, cocaine, MDMA/ecstasy (methylenedioxy-methamphetamine), ketamine, GHB (gamma-hydroxy-butyrate), marijuana, and nitrate inhalants (poppers) among gay and bisexual men both between and within cities (NYC and LA). Levels of recent drug use were fairly consistent between New York City and Los Angeles; however there was some between and within city racial and ethnic variance. In particular, Asian/Pacific Islander men were among those least likely to report use of some drugs. Findings suggest substance use in the gay community permeates geographic boundaries in addition to some racial and ethnic boundaries such that interventions targeting drug-using gay and bisexual men should appropriately attend to racial and ethnic diversity within communities.     

Black Gotham: African Americans in New York City, 1900–2000

For almost four centuries, African Americans in New York City have engaged in ethnic “dream-work,” shaping the city and being shaped by the city in return. The longstanding practice of racism forced a heterogeneous community of Blacks—originating in different parts of the country and the world, speaking many languages, and comprised of different economic classes— to coalesce as a community in order to challenge their subjugation. This article explores the issues, conditions, and experiences that frame the coalescence of the African American community in New York City during the twentieth century, highlighting how racial identities have been produced in the city. In the first part of this article, I reflect on the presence of Blacks in New York City to illuminate some of the common themes that have emerged from the African American experience in Gotham. The second section is a historical exploration of the black experience in New York City, illuminating the conditions, expectations, events, and spaces that have shaped its formation.