Exploratory Study of a Rehabilitative Heat-Resilient Green-Blue Infrastructure.
Case Study Lleida, Catalonia, Spain.
Category> Research; Landscape; Planning; Design.
Course> Independent project in Landscape Architecture for Sustainable Urbanisation – Master’s Programme. Swedish University of Agricultural Sciences, SLU
Location> Lleida, Spain.
Year> 2023-2024
This study explores how landscape architecture can be crucial in addressing the growing problem of urban heat, particularly in Mediterranean cities. With increasing heat waves posing severe threats to human health and the environment, integrating strategies for ecological restoration and urban resilience into city planning is more critical than ever. The recent restoration laws in Europe have made this issue even more urgent, emphasising the need to create healthier environments for people and ecosystems.
The research highlights how thoughtful landscape design and planning can help develop cooler microclimates and more adaptable urban spaces.
Study
For this, I immersed myself in the literature to explore strategies and critical variables that helped to guide the study and the proposal: a network of interconnected cooling patches that can mitigate while ecologically rehabilitating disappearing ecosystems in Lleida.
Due to its particularities, the city of Lleida, Catalonia, Spain, was used as the case study. It is a medium-sized city with extensive agricultural and industrial surroundings that suffers from recurrent extreme heat.
Heat stress impacts at different scales, so the analysis and proposal needed to respond to this using a multi-scale approach. The study calculated land surface temperature [LST], visited some existing cooling islands, and evaluated their ecosystem services. Altogether, it helped to assess how land use, urban form, and agricultural practices affect heat stress.
Patch analysis
Existing cooling island analysis, based on the LST study, and the existing land use.
The findings were clear: tree-covered areas showed the most significant cooling effect, with surface temperatures varying by as much as 13°C between different parts of the city. However, the fragmented nature of green spaces and water-intensive agriculture reduce the city’s resilience. The study also underscored the importance of biodiversity, connectivity, and multifunctionality in building resilient urban networks.
Three native forest types and their distribution were identified as potential referent habitats to guide restoration planning. However, much remains to be learnedn about how xeric landscapes can contribute to this effort.
Testing a network of patches in Lleida
Geomorphological habitat distribution proposal.
Five different habitats are part of this area's disappeared ecosystems, and their species diversity is distributed throughout the territory based on the geomorphological condition.
Evergreen forests, such as Carrasca forest would be predominant in the western part, while Maquis or Pine tree forests would resist the drier conditions of the hills and the eastern part.
Carrasca habitat representation.
Proposal network of cooling islands with distances minor than 300m, considering predominant winds from the west.
These findings have important implications for urban planners and designers. To make cities more resilient, we must adopt a holistic approach that blends heat mitigation strategies with ecological restoration.
Small, community-driven interventions, combined with larger, long-term plans, will help create healthier, cooler, and more sustainable urban environments.