3 resultados para Deserts.
em Aston University Research Archive
Resumo:
The “food deserts debate can be enriched by setting the particular circumstances of food deserts – areas of very limited consumer choice – within a wider context of changing retail provision in other areas. This paper’s combined focus on retail competition and consumer choice shifts the emphasis from changing patterns of retail provision towards a more qualitative understanding of how “choice” is actually experienced by consumers at the local level “on the ground”. This argument has critical implications for current policy debates where the emphasis on monopolies and mergers at the national level needs to be brought together with the planning and regulation of retail provision at the local, neighbourhood level.
Resumo:
Focuses on deprived neighbourhoods where instances of “food deserts have been found and explores, through focus groups, consumer experiences of food store choices. Focusing on suburban neighbourhoods in Portsmouth, identifies significant differences in experiences of choice both between and within neighbourhoods. In some localities, the research also finds dissatisfaction with the (supposedly-coveted) “small local store”. Shows that choice is very different from provision, and conceptualises how consumers’ circumstances, situation and individual characteristics can significantly reduce a broad theoretical provision of food stores to a limited set of perceived real choices.
Resumo:
Agriculture accounts for ~70% of freshwater usage worldwide. Seawater desalination alone cannot meet the growing needs for irrigation and food production, particularly in hot, desert environments. Greenhouse cultivation of high-value crops uses just a fraction of freshwater per unit of food produced when compared with open field cultivation. However, desert greenhouse producers face three main challenges: freshwater supply, plant nutrient supply, and cooling of the greenhouse. The common practice of evaporative cooling for greenhouses consumes large amounts of fresh water. In Saudi Arabia, the most common greenhouse cooling schemes are fresh water-based evaporative cooling, often using fossil groundwater or energy-intensive desalinated water, and traditional refrigeration-based direct expansion cooling, largely powered by the burning of fossil fuels. The coastal deserts have ambient conditions that are seasonally too humid to support adequate evaporative cooling, necessitating additional energy consumption in the dehumidification process of refrigeration-based cooling. This project evaluates the use of a combined-system liquid desiccant dehumidifier and membrane distillation unit that can meet the dual needs of cooling and freshwater supply for a greenhouse in a hot and humid environment.