The concept of food deserts, as a measure of low-income neighborhoods with limited access to affordable and healthy produce, can be helpful as a tool to quantify and compare food vulnerabilities, as many recent studies have demonstrated. However, the term masks the role that systems of racism and capitalism have played in producing food vulnerabilities. To explore this gap in the literature, this dissertation addresses two central research questions. The first central research question asks, what are the influential demographic and spatial patterns that have shaped supermarket access in low-income neighborhoods across Atlanta from 1980 to 2010? This study addresses this question using geo-spatial and quantitative analytical methods. The second research question asks, how have the movement of capital, the influence of urban political regimes, and community-based organizations shaped food environments in historically black neighborhoods in Atlanta from 1980 to 2010? These relationships are explored through a qualitative analysis of community redevelopment plans for two case study neighborhoods. The study reveals several findings. First, race, poverty, and population density spatially overlap with shifts in Atlanta's supermarket locations. Atlanta has a clear racial and income dividing line that splits the city into higher-income and majority white neighborhoods to the north and low-income/poor and majority black neighborhoods to the south, which has intensified over the thirty-year study period. Second, racial segregation and the concentration of poverty reinforce the vulnerability experienced by low-income neighborhoods, and produces limited access to supermarkets and other neighborhood retail outlets. Third, even though neighborhood redevelopment plans contained resident's concerns about limited supermarket access, the plans' visions often required both the public sector and private investment. Fourth, the concept of food deserts is too limited. Instead, a new conceptual understanding is needed to identify processes and structures that have produced whole communities of people that have been food deserted.

La vulnérabilité alimentaire d'un individu peut être définie comme la susceptibilité qu'il a de faire face, à plus ou moins longue échéance, à une situation d'insécurité alimentaire, au cours de laquelle il n'a plus accès à une nourriture suffisante et satisfaisante d'un point de vue nutritionnelle et sanitaire, et correspondant à ses préférences culturelles. l'enjeu de la thèse est de comprendre les facteurs qui déterminent le niveau de vulnérabilité alimentaire des citadins – puisqu'on s'intéressera au cadre urbain. les citadins élaborent des stratégies de gestion des ressources qu'ils peuvent mobiliser pour faire face aux changements de l'environnement dans lequel ils vivent ; ils s'inscrivent dans le système alimentaire urbain et élaborent des choix de vie (migrations, emploi, logement, investissements) qui tracent une trajectoire de vie, dont leur situation alimentaire dépend. l'enjeu de la thèse est de comprendre ce qui, dans la position que l'individu occupe au sein de son environnement, accroît ou réduit sa vulnérabilité. le terrain d'étude sera la ville de hanoi, capitale du viêt-nam, dont une partie des habitants souffre d'une situation précaire, les conduisant, en cas de choc, à ne plus pouvoir faire face et à se retrouver en insécurité alimentaire. / With a focus on underpriviledged urban dwellers’ everyday practices in Hanoi, this study aims to show the construction of individual and household food insecurity in a city where living standards have dramatically improved over the last three decades. It demonstrates that food budget plays a key role in livelihoods management in an unstable context, by serving as a tool for underprivileged people to adjust to shocks. Therefore, individuals’ food vulnerability should be understood as a long-term livelihoods securitization process.This study shows that livelihoods securitization is based on sustaining social networks. These networks are constantly reactivated by an ongoing circulation of money and goods, and they are the basis of daily mutual assistance at the ward scale. This reveals a strong relationship between lived space and solidarity networks in which risks are mutualized.The analysis of people’s working trajectories shows a high capacity for adaptation, with individuals rearranging their livelihoods (jobs, food production for family’s consumption, rental income, etc.) according to their need and the changes in their environment. Nevertheless, in the context of a metropolizing city, the people’s capacities to take advantage of this development varies greatly. This contrast is reinforced by the fact that resources developments (economic, social, spatial) have a cumulative effect. As a consequence, inequalities are deepened in Hanoi, both at the city scale and wards scale.Such inequalities can be seen in the increasing differences between food practices and consumption patterns among urban dwellers. Products as well as their origines get more diverse, creating new safety concerns ; purchasing places diverge more and more between the rich and the poor ; and foodborne diseases appear while malnutrition issues remain. All along the food supply chain, current shifts illustrate a process that can be called food emergence.Finally, this study reveals that it is primarily non-food phenomenons that result in food insecurity ; it widens the food security framework. In this way, the analysis of urban dwellers’ daily practices provides an illustration of the ongoing urban emergence process of Vietnamese capital.

Small islands developing states (SIDS) sustainability is a United Nations’ aim. Their markets are often influenced by external policies imposed by larger economies. Could an anti-competitive measure affect the food vulnerability of a SIDS? This research examines the effects of an external non-tariff measure (NTM) on Puerto Rico’s (PR) agribusinesses. It explores the effects of a maritime cabotage regulation (US Jones Act) on the affordability and accessibility of produce and grains. PR imports 100% of their needs of grain and over 85% of fresh produce. PR’s food imports are generally from the US and the trade service is restricted to the use of the US maritime transportation. As a result, the supply chain of these two sectors although different, are limited by the US Act that may impact the cost of food, its availability, firms’ efficiency and other structures of production. Using a mixed convergent design, PR’s agrifood supply chains were explored and analysed in relation to the maritime cabotage regulation. Oligopolistic structures and collusion between maritime transporters and local agribusinesses importers limit the access to data, but other internal factors also have a role. Fieldwork shows that while the cabotage regulation itself is a constraint, interaction with others NTM and the current political framework between US and PR are relevant. Factors such as lack of efficiency, poor innovation and a self-limitation of the agribusinesses firms were found. The novelty of this research is the use of mixed methods to evaluate the effects of cabotage on the agrifood supply chain.

Small islands developing states (SIDS) sustainability is a United Nations’ aim. Their markets are often influenced by external policies imposed by larger economies. Could an anti-competitive measure affect the food vulnerability of a SIDS? This research examines the effects of an external non-tariff measure (NTM) on Puerto Rico’s (PR) agribusinesses. It explores the effects of a maritime cabotage regulation (US Jones Act) on the affordability and accessibility of produce and grains. PR imports 100% of their needs of grain and over 85% of fresh produce. PR’s food imports are generally from the US and the trade service is restricted to the use of the US maritime transportation. As a result, the supply chain of these two sectors although different, are limited by the US Act that may impact the cost of food, its availability, firms’ efficiency and other structures of production. Using a mixed convergent design, PR’s agrifood supply chains were explored and analysed in relation to the maritime cabotage regulation. Oligopolistic structures and collusion between maritime transporters and local agribusinesses importers limit the access to data, but other internal factors also have a role. Fieldwork shows that while the cabotage regulation itself is a constraint, interaction with others NTM and the current political framework between US and PR are relevant. Factors such as lack of efficiency, poor innovation and a self-limitation of the agribusinesses firms were found. The novelty of this research is the use of mixed methods to evaluate the effects of cabotage on the agrifood supply chain.