Tous les articles par Eric Duchemin

Small-scale urban agriculture results in high yields but requires judicious management of inputs to achieve sustainability

Growing food in cities for human consumption could be one means of increasing global food supply in the face of rising population growth and global food security concerns. While previous studies have shown that urban agricultural systems are productive, few studies provide yield figures that incorporate data on the inputs used to achieve the outputs. Across 13 urban community gardens, we show that yields were nearly twice the yield of typical Australian commercial vegetable farms. However, economic and emergy (embodied energy) analyses indicated they were relatively inefficient in their use of material and labor resources. Balancing the sustainability of urban food production with the cost of inputs is important to determine the trade-offs required to achieve high yields.

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Cartographie des jardins individuels dans l’arrondissement Rivière-des-Prairies-Pointe-aux-Trembles à Montréal (Québec, Canada)

En collaboration avec plusieurs partenaires, le Laboratoire sur l’agriculture urbaine (AULAB) travaille sur un projet d’évaluation de l’agriculture urbaine comme infrastructure verte de résilience individuelle et collective face aux changements climatiques et sociaux. Planifié sur trois ans (20176-2020), ce projet de recherche servira à outiller les acteurs sociaux québécois d’un guide d’évaluation sur les bénéfices de l’agriculture urbaine quant à l’insécurité alimentaire, la justice alimentaire et la résilience individuelle et collective pour l’alimentation, le tout dans un contexte de changements climatiques.

Le travail de d’identification des jardins potagers présenté dans le cadre de ce billet a été réalisé par Maylis Blanc de Sciences Po Bordeaux (France), qui était en stage à AULAB à l’été 2018, Le stage  a été réalisé sous la supervision de Eric Duchemin, Directeur scientifique et formation de AU/LAB. Les analyses spatiales et la cartographie SIG ont été réalisées par Hien Pham, professeure à l’UQAM et collaboratrice à AULAB.

Résumé : Dans le cadre d’une recherche l’équipe du Laboratoire sur l’agriculture urbaine (AU/LAB) a cartographié par Image satellite la présence de jardins individuels sur zone de 42,3 km² du territoire dans l’arrondissement Rivière-des-Prairies-Pointe-aux-Trembles à Montréal, dont une zone d’environ 10,6 km2 de zone d’emplois. Cet arrondissement situé à l’est de la ville de Montréal est séparé en deux par une importante zone industrielle.

Sur le territoire étudié Sur le territoire Rivière-des-Prairies-Pointe-aux-Trembles 1328 jardins ont été identifiés par image satellite (2012). Ces derniers sont essentiellement des jardins individuels sur des terrains privés.

Figure 1. Répartition du nombre de jardins et de la superficie des jardins sur le territoire de l’arrondissement Rivière-des-Prairies par rapport à Pointe-aux-Trembles.

Les jardins représentent une superficie totale de 44 538 m2, soit 4,4 ha avec une superficie moyenne de 22,5m2 et une superficie médiane de 26,3m2. Le potager identifié le plus grand fait 426 m2 et le plus petit 3,2 m2.

Si on examine uniquement le nombre de lots résidentiels ayant un potager par rapport au nombre de lot total on observe que pour RDD-PAT le pourcentage est de 6%, tandis que sur les autres territoires ce pourcentage est de 11% pour Chomedey, 8% pour Montréal-Nord, 7% pour Terrebonne et 5% pour Longueuil.

Figure 2. RDP-PAT – Déviation standard du Location quotient (LQ) (gauche)) et LQ hotspot (droite) sur le territoire de l’arrondissement Rivière-des-Prairies-Pointe-aux-Trembles.

Figure 3. Images de la zone avec la plus forte conventration de potagers dans l’arrondissement Rivière-des-Prairies-Pointe-aux-Trembles.

Dans la zone d’étude, la densité des jardins donne une moyenne de 42 jardins au km2 pour l’ensemble du territoire (hors de la zone d’emplois de 10,6km2). Toutefois comme pour les autres territoires, cartographiés  dans le cadre de cette recherche, cette distribution est très variable d’un quartier à l’autre de la zone d’étude, la densité étant plus forte dans Rivière-des-Prairies par rapport à Pointe-aux-Trembles. La densité est aussi plus forte dans le secteur est de Rivière-des-Prairies, le long des boulevards Maurice-Duplessis Boulevard and Perras Boulevard. Un secteur qui regroupe une zone résidentielle avec des maisons unifamiliales sur des lots importants. C’est aussi une zone dont la densité résidentielle est plus forte qu’à l’ouest de RDP.

Pour consulter la cartographie sur le territoire de l’arrondissement Montréal-Nord
Pour consulter la cartographie sur le territoire de l’arrondissement Chomedey à Laval
Pour consulter la cartographie sur le territoire de l’arrondissement à Longueuil
Pour consulter la cartographie sur le territoire de l’arrondissement à Terrebonne

Pour consulter la recherche complète de ce territoire :

Cécile Renaud (2018), Portrait de l’agriculture urbaine à Terrebonne : étude sur les jardins potagers individuels et l’implication des acteurs

Le projet de recherche Évaluation de l’agriculture urbaine comme infrastructure verte de résilience individuelle et collective face aux changements climatiques et sociaux est soutenu financièrement par :

Cartographie des jardins individuels à Terrebonne (Québec, Canada)

En collaboration avec plusieurs partenaires, le Laboratoire sur l’agriculture urbaine (AULAB) travaille sur un projet d’évaluation de l’agriculture urbaine comme infrastructure verte de résilience individuelle et collective face aux changements climatiques et sociaux. Planifié sur trois ans (20176-2020), ce projet de recherche servira à outiller les acteurs sociaux québécois d’un guide d’évaluation sur les bénéfices de l’agriculture urbaine quant à l’insécurité alimentaire, la justice alimentaire et la résilience individuelle et collective pour l’alimentation, le tout dans un contexte de changements climatiques.

Le travail présenté dans le cadre de ce billet a été réalisé par Cécile Renaud de l’École Nationale des Travaux Publics de l’Etat, qui était en stage à AULAB à l’été 2018. Le stage  a été réalisé sous la supervision de Eric Duchemin, Directeur scientifique et formation de AU/LAB, avec la participation de Hien Pham, professeure à l’UQAM et Collaboratrice à AULAB.

Résumé : Dans le cadre d’une recherche l’équipe du Laboratoire sur l’agriculture urbaine (AU/LAB) a cartographié par Image satellite la présence de jardins individuels sur zone de 93,3 Km2 du territoire de la ville de Terrebonne, dont une zone de 27,2 km2 de zone résidentielle (29% de la surface urbanisée).Le territoire totale de la ville de Terrebonne est de 154,1 km2, avec 40% en territoire agricole.

Figure 1. Délimitation du Territoire de la ville de Terrebonne.

Sur le territoire étudié Sur le territoire de Terrebonne 2317 jardins ont été identifiés par image satellite (2012). Ces derniers sont essentiellement des jardins individuels ou des serres sur des terrains privés.

Les jardins représentent une superficie totale de 53 723 m2, soit 5,4 ha avec une superficie moyenne de 23m2 et une superficie médiane de 12,5m2. Le potager identifié le plus grand fait 644 m2 et le plus petit 1,61 m2. La surface que l’on retrouve le plus fréquemment est de 5 m2.

Si l’on considère la surface totale de Terrebonne, qui vaut 15 412 ha, les jardins identifiés représentent 0,05% du territoire urbanisé. Ce qui nettement en dessous du ratio de 0,2% et 0,4% observé, respectivement, à Longueuil et Chomedey et à Montréal Nord. Toutefois, si on examine uniquement le nombre de lots résidentiels ayant un potager par rapport au nombre de lot total on observe que pour Terrebonne le pourcentage est de 7%, tandis que sur les autres territoires ce pourcentage est de 11% pour Chomedey, 8% pour Montréal-Nord et 5% pour Longueuil. Ainsi ce premier écart observé est particulièrement la résultante de la forme urbaine de Terrebonne et la présence de grands terrains résidentiels.

Dans la zone d’étude, la densité des jardins donne une moyenne de 85 jardins au km2 en zone résidentielle, mais cette distribution est très variable d’un quartier à l’autre de la zone d’étude, la densité étant plus forte dans la région centrale et à l’ouest du territoire.

Par ailleurs, on constate une très grande variation spatiale dans la superficie des potagers. Les zones avec une forte densité accueillent généralement de plus petits potager, tandis que la localisation des jardins potagers de grande superficie est souvent aux bords des zones urbanisées et non en leur centre.

Pour consulter la cartographie sur le territoire de l’arrondissement Montréal-Nord
Pour consulter la cartographie sur le territoire de l’arrondissement Chomedey à Laval
Pour consulter la cartographie sur le territoire de l’arrondissement à Longueuil
Pour consulter la cartographie des jardins individuels dans l’arrondissement Rivière-des-Prairies-Pointe-aux-Trembles à Montréal 

Le projet de recherche Évaluation de l’agriculture urbaine comme infrastructure verte de résilience individuelle et collective face aux changements climatiques et sociaux est soutenu financièrement par :

The economic performance of urban gardening in three European cities – examples from Ljubljana, Milan and London

Urban gardening is not a new phenomenon but it has received considerably more practical and academic interest in recent years. Studies on economic aspects such as crop yields, inputs and outputs of production, productivity, gross margins and the contribution to home economics are rare, especially in Europe. While urban gardening plays an important role in the Global South, its role in Western Europe for food productivity and home economics is currently under-researched. The aim of this study is to analyse European urban gardeners’ economic performance and self-sufficiency on a household level, as well as to reach a better understanding of their contribution to food self-provision and food security in the metropolitan areas. In a study carried out in 2014 with on-site personal and with online questionnaires participated 180 urban gardeners from three case study cities (Ljubljana, Milan, and London). Results from the economic analysis showed that although for most urban gardeners, profit is not their main motivation, the economic calculation shows that productivity in small urban plots can be comparable to market garden production. Urban gardeners are saving money, especially when, compared to retail prices for regular produce or organic produce, their input is included in the gross margin calculation. We conclude that, in the case-study cities, the self-provisional potential of urban gardeners’ households to adequately cover the annual vegetable need of five-a-day servings can be met under three conditions: (1) sufficient garden size; (2) increased area productivity, and (3) sufficient labour-hour inputs.

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Considerations for reducing food system energy demand while scaling up urban agriculture

There is an increasing global interest in scaling up urban agriculture (UA) in its various forms, from private gardens to sophisticated commercial operations. Much of this interest is in the spirit of environmental protection, with reduced waste and transportation energy highlighted as some of the proposed benefits of UA; however, explicit consideration of energy and resource requirements needs to be made in order to realize these anticipated environmental benefits. A literature review is undertaken here to provide new insight into the energy implications of scaling up UA in cities in high-income countries, considering UA classification, direct/indirect energy pressures, and interactions with other components of the food–energy–water nexus. This is followed by an exploration of ways in which these cities can plan for the exploitation of waste flows for resource-efficient UA. Given that it is estimated that the food system contributes nearly 15% of total US energy demand, optimization of resource use in food production, distribution, consumption, and waste systems may have a significant energy impact. There are limited data available that quantify resource demand implications directly associated with UA systems, highlighting that the literature is not yet sufficiently robust to make universal claims on benefits. This letter explores energy demand from conventional resource inputs, various production systems, water/energy trade-offs, alternative irrigation, packaging materials, and transportation/supply chains to shed light on UA-focused research needs. By analyzing data and cases from the existing literature, we propose that gains in energy efficiency could be realized through the co-location of UA operations with waste streams (e.g. heat, CO2, greywater, wastewater, compost), potentially increasing yields and offsetting life cycle energy demands relative to conventional approaches. This begs a number of energy-focused UA research questions that explore the opportunities for integrating the variety of UA structures and technologies, so that they are better able to exploit these urban waste flows and achieve whole-system reductions in energy demand. Any planning approach to implement these must, as always, assess how context will influence the viability and value added from the promotion of UA.

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Assessing Current Local Capacity for Agrifood Production To Meet Household Demand: Analyzing Select Food Commodities across 377 U.S. Metropolitan Areas – Environmental Science & Technology (ACS Publications)

Increasing food production in local urban and peri-urban areas is articulated as a potential way for local governments to achieve multiple sustainability outcomes (environmental, social, and human health). However, scientific judgements on localization are difficult to make because the degree of current food localization has not been systematically measured or defined across large numbers of cities. We develop new methods to quantify current local capacity for food production to meet total household agrifood demand, harmonizing bottom-up and top-down approaches to assess direct-plus-embodied agrifood demand of both fresh and processed foods. We find unique patterns of localization for different agrifoods, with 21% of U.S. metropolitan statistical areas (MSAs) currently capable of local self-sufficiency for eggs and milk equivalents embodied in diet, versus 12% and 16% of MSAs self-sufficient in fruits and vegetables, respectively. Focusing only on the direct fresh food demand, increased current local capacity (e.g., 45% MSAs self-sufficient in direct fluid milk), which also increases with production distances around cities. Overall, significant agricultural production is found to already occur in and around U.S. MSAs for these items. Multivariable analysis finds that state policies that promote urban agriculture may influence greater localization, which, interestingly, is independent of population density. Such spatial demand–production analysis is the first step in informing sustainable city or regional food policies and envisioning spatial food supply chains to urban areas.

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Rethinking resilience: home gardening, food sharing and everyday resistance

Resilience and food self-provisioning (FSP), terms that until recently were deployed primarily in the study of livelihoods in the Global South, are now attracting attention from alternative food scholarship in the Global North. Drawing on a large-scale survey conducted in the Czech Republic, this article investigates FSP as a social resilience-enhancing set of practices. In addition to the traditional reading of FSP as a passive, defensive and crisis-deflecting form of resilience, this article puts forward an alternative conceptualisation of resilience as a proactive, preventative, future-oriented and transformation-enabling capacity that runs counter to the tenets of neoliberalism. La résilience et l’autoproduction alimentaire (food self provisioning – FSP), termes qui jusqu’à récemment étaient principalement utilisés dans l’étude des moyens de subsistance dans les pays du Sud, attirent désormais l’attention des spécialistes de l’alimentation alternative dans le Nord. S’inspirant d’une enquête à grande échelle menée en République tchèque, cet article étudie les FSP comme un ensemble de pratiques améliorant la résilience sociale. En plus de la lecture traditionnelle du FSP en tant que forme de résilience passive, défensive et mitigatrice, cet article propose une conceptualisation alternative de la résilience comme une capacité proactive, préventive, orientée vers le futur et créatrice d’une capacité de transformation allant à l’encontre des principes du néolibéralisme.

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Carrefour installe des potagers autour de ses hypermarchés

Carrefour a inauguré jeudi dernier un potager sur le toit de son hypermarché de Villiers-en-Bière en Seine-et-Marne, le plus grand de France en superficie. Sur une surface de 1200 mètres carrés, des plantes aromatiques, des fruits rouges, des kiwis, des épinards, des tomates ou encore des salades y sont cultivés dans des bacs hors-sol. Une fois récoltés à maturité, ils seront vendus au client dans les rayons de l'hypermarché. Les premières ventes devraient s'effectuer début mai, selon l'enseigne. «Ce potager s'inscrit dans la politique de RSE (Responsabilité Sociale et Environnementale, ndlr) de l'entreprise, et des filières qualité du groupe Carrefour. Aujourd'hui, le client attend des produits de qualité, d'une grande fraîcheur, avec du goût et en circuit ultra-court», indique au Figaro Éric Sauvage, secrétaire général de Carrefour France.

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Beyond Productivity: Considering the Health, Social Value and Happiness of Home and Community Food Gardens

We are living in an age of concern for mental health and wellbeing. The objective of the research presented in this paper is to investigate the perceived health, social value and happiness benefits of urban agriculture (UA) by focusing on home and community food gardens in South Australia. The results reported in this paper are from “Edible Gardens”, a citizen science project designed to investigate the social value, productivity and resource efficiency of UA in South Australia. Methods include an online survey and in-field garden data collection. Key findings include: dominant home gardener motivations were the produce, enjoyment, and health, while dominant community gardener motivations were enjoyment, connection to others and the produce. Exploratory factor analysis revealed four key factors: Tranquillity and Timeout, Develop and Learn Skills, the Produce, and Social Connection. The key difference between home and community gardeners was an overall social connection. Although home gardeners did not appear to actively value or desire inter-household social connection, this does not mean they do not value or participate in other avenues of social connection, such as via social learning sources or by sharing food with others. The combined results from this research regarding health and wellbeing, social connection and happiness support the premise that engagement in home or community food gardening may provide a preventative or supportive role for gardener health and wellbeing, regardless of whether it is a conscious motivation for participation.

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Urban Agriculture: Models-in-Circulation from a Critical Transnational Perspective

Urban Agriculture (UA) is practiced around the globe (Biel, 2016), supported and advocated by a diversity of actors ranging from local neighbourhood groups to supra-national bodies (e.g. FAO, 2014; Mougeot, 2006; UN Habitat, 2014). As such, UA must be understood as one of planning’s current “models-in-circulation” (Roy and Ong, 2011), characterised by the traveling of ideas and policies in a globalised world (Healey, 2013). UA operates at a diversity of scales and engages a variety of actors. Yet, as a model-in-circulation, only some of the ways in which UA is practiced are promoted globally and influence the way UA is perceived, thus disregarding UA’s highly specific manifestations in different social/economic/political contexts around the world. We use a critical transnational perspective for a qualitative analysis of collective (rather than individual) UA practices happening in small-scale, left-over public spaces in three very different locations in Latin America and Europe (Bogotá and Medellin in Colombia, and Vienna in Austria) to gain insights into how policies and initiatives inspired by typical models-in-circulation affect the situation on ground. The analysis shows that the reliance on such models can act like a filter impeding the acknowledgment that actors, objectives and barriers for UA practices are more complex, nuanced and multifaceted than those that a simple model can contain. As a result the benefits UA can yield are only partially attained. The conceptual device of translocal is subsequently formulated as one conveying the traveling of ideas locally, which can enrich and root models-in-circulation.

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Digging for the roots of urban gardening behaviours

Urban green spaces make a significant contribution to the social and ecological environment in cities, and the decisions of green space managers have direct impacts at both local and city scales. However most studies have focussed on public green spaces, despite privately managed gardens collectively forming a large proportion of urban green. The aim of this qualitative paper is to understand why people become involved in gardening and why they choose environmentally friendly gardening practices. We conducted semi-structured interviews with 23 gardeners in Lausanne, Switzerland and analysed them according to their content. Three major themes emerged as motivations for gardening: wellbeing, social aspects, and outputs (both tangible, such as food, and intangible, such as the feeling of having produced food). Motivations for gardening practices were grouped into extrinsic factors, such as practical constraints, inspiration from neighbours, following regulations, and social controls; and intrinsic, which were primarily based on knowledge and experience. Our results provide some evidence of the tangible and beneficial outcomes of gardening and provide additional support to urban decision makers with an interest in the management of urban green spaces.

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The Role of Urban Agriculture as a Nature-Based Solution: A Review for Developing a System

Urbanization and achieving sustainable agriculture are both major societal challenges. By reducing food miles and connecting people with nature, food cultivation in cities has several major advantages. However, due to further urban development (peri-) urban agriculture (UPA) is under threat. To strengthen UPA, we argue for considering UPA as a nature-based solution (NbS) supporting systemic approaches for societal challenges. However, academic knowledge on UPA’s contribution to various societal challenges of urbanization is still fragmented. This study addresses the gap by conducting a systemic literature review, incorporating 166 academic articles focusing on the global north. The results of the review show that UPA contributes to ten key societal challenges of urbanization: climate change, food security, biodiversity and ecosystem services, agricultural intensification, resource efficiency, urban renewal and regeneration, land management, public health, social cohesion, and economic growth. The value of UPA is its multifunctionality in providing social, economic and environmental co-benefits and ecosystem services. When implementing UPA, social, institutional, economic, technical, geographical, and ecological drivers and constraints need to be considered. To upscale UPA successfully, the study develops an integrative assessment framework for evaluating the implementation and impact efficiency of UPA. This framework should be tested based on the example of edible cities

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Let Them Eat Kale : The Misplaced of Food Access

This Article examines the emergence of food access as a policy issue, current approaches to increasing food access, and possible alternatives. Part I discusses the development of the current food access narrative, focusing on its appeal to policymakers, urban planners, and public health officials. Part II describes policies to increase access to food retail. Part III reviews research on the relationship between food retail and health outcomes. Part IV examines why increasing food access persists as a policy goal despite its demonstrated failure to reduce health inequities. Finally, Part V proposes alternative strategies for reducing economic and health disparities within food systems.

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Remote Sensing Data and Methods for Identifying Urban and Peri-Urban Smallholder Agriculture in Developing Countries and in the United States – Reference Module in Earth Systems and Environmental Sciences/Comprehensive Remote Sensing – 9.19

The world has experienced rapid urbanization over the past five decades, with resulting substantial changes to the food system. Strong urbanization is associated with economic growth, which allows for investment in substantial increases in energy, water, and land used in intensive agriculture required to support urban populations. Given the cost of moving goods from distant regions, there has been a growth of small-scale agriculture within urban areas to meet the needs of its population. In this paper, we will describe satellite remote sensing data and methods that can identify urban and peri-urban farms and gardens in the United States and in developing countries, starting with global approaches and then providing case studies that explore different techniques. An examination of the increasing importance of local food to urban populations, and the role remote sensing can play in identifying where urban farming is occurring and its change through time will conclude the article.

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