The implementation of urban gardens on building rooftops could help boost the production of agricultural crops and ensure the food security of cities.
Urban agriculture on rooftops is an optimal and feasible solution to produce healthy, fresh and sustainable food in the face of increasing demand for these products in cities, according to a study by the Institute of Environmental Science and Technology (ICTA-UAB).
According to this research, carried out within the framework of the FertileCity project, the implementation of urban gardens on building rooftops would allow the production of agricultural foods and help guarantee the food sovereignty of cities, which are increasingly populated. ICTA researchers estimate that by 2050, 66% of the world's population will reside in cities and the demand for food will increase by 30%.
In this context, urban agriculture is not only a more sustainable food production system, but also leads to improvements in air quality and temperatures, reduces the environmental impact of freight transport and helps support local economies.
On the rooftops
The FertileCity project, which also counts with the participation of researchers from the Polytechnic University of Catalonia (UPC), has analyzed the implementation of urban agriculture on the roofs of buildings with the aim of taking advantage of these empty spaces through the installation of greenhouses.
The study highlights that one of the factors that limit the development of urban agriculture is the fear that air pollution in cities could have an impact on the healthiness of cultivated agricultural foods.
The results show that the vegetables produced both in the ICTA-UAB greenhouse (located on the UAB campus next to the AP-7) and in other orchards located in areas with high traffic density in Barcelona are not contaminated with heavy metals, and that the levels of nickel, arsenic, cadmium and lead are well below the legal limits.
The study analyzed the production of soilless vegetables using perlite as a substrate and providing the plant with the necessary nutrients, together with irrigation water from the rain. The contamination with heavy metals through the substrate was also ruled out.