About this Research Topic
Nature-based solutions (NBS) are considered key elements for sustainable urban development and green transition by addressing manifold socio-environmental challenges, including the support and maintenance of biodiversity, the adaptation to extreme events in light of global climate change, and the improvement of public health and human well-being, ultimately calling for the uptake and mainstreaming of NBS into urban policy and planning. To support the adoption of NBS, it is crucial to assess the conditions that affect their (cost-)effectiveness, including their capacity to safeguard the long-term protection of ecosystem functions through adequate design and management. At the same time, it is also key to minimize trade-offs of NBS to ensure acceptance and sustainability.
In this regard, previous findings emphasize that NBS benefits and trade-offs are mediated by numerous spatial factors at multiple spatiotemporal scales. In urban systems, these spatial factors are intertwined with the local physical contexts determined by the urban form or morphology of the city. In fact, the size, shape, and spatial configuration of the physical elements that compose the city affect NBS benefits in multiple ways. First, it is well understood how different urban forms generate different environmental and social impacts, including the exposure and vulnerability to different hazards, which in turn affect the need for NBS. Second, different urban morphologies are characterized by a different potential and opportunities to integrate NBS (e.g., high density neighborhoods may offer only few spaces where some types of NBS can fit). Third, contextual factors such as (micro-) climatic conditions, water availability, and proximity to infrastructure, among others, influence the capacity of NBS to provide ecosystem services and disservices, thus limiting their effects. Finally, urban form is often linked to the socio-economic profile of the inhabitants or the users of the urban space, hence to the beneficiaries of NBS.
Conversely, also NBS themselves shape urban morphology, and thus contribute to the definitions of different urban forms and their socio-economic-ecological attributes. This is particularly true for NBS interventions that imply major changes, such as the renaturation of a riverbed or the creation of large urban green spaces, that modify the physical context of entire parts of the city. But it is also true for smaller greening interventions that can change the appearance of a neighborhood and its attractiveness, sometimes even triggering gentrification processes.
Urban morphology may be characterized through many metrics and indicators, for example, as a function of land-cover and land-use; through built-up and non-built-up densities; based on building structure and vegetation types, diversity and agglomeration; by consideration of the spatial configuration of street canyons including their width, height, and orientation; or based on topological relationships including proximities between the various (non-)built-up elements etc. Similarly, there is a multitude of indicators for the characterization, assessment and evaluation of NBS, including blue-green type, vegetation and/or canopy cover, species selection and species diversity, size, spatial clustering/dispersion, walkability, accessibility, the applied level of engineering and management, as well as the capacities for the delivery of ecosystem services, e.g., carbon sequestration rate, cooling potential, shaded area, rate of pollutants removal, or peak water flow reduction.
This Research Topic welcomes Original Research, (Systematic) Review Articles, Mini Reviews, and Perspective Articles on the interactions between urban morphology and NBS. It includes research on the (maximization of) benefits as well as (minimization of) trade-offs delivered by NBS in distinct urban contexts, e.g., by assuming the perspective of how urban morphology mediates the delivery of ecosystem services and/or disservices through NBS, or by exploring the analytical lens of how the delivery of benefits or trade-offs is impacted through NBS design and how, subsequently, NBS shape and (re-)define urban form. Issues that are part of this Research Topic include, but are not limited to:
o Development of indicators for the characterization of urban form and urban patterns, or NBS respectively, including the integration of socio-economic data, as a pre-requisite for assessing the potential and benefits of NBS integration
o Modelling of the spatiotemporal interactions between urban morphology and the delivery of benefits and/or trade-offs by NBS, including the assessment of edge or adjacency effects, and the maximization of benefits and/or minimization of trade-offs at different spatiotemporal scales
o Exploration of the shaping and (re-)definition of the urban form and socio-economic-ecological conditions through NBS and the benefits or trade-offs delivered by them
o People’s preferences towards the changes in urban form brought about by NBS
o Assessment of factors for the long-term safeguarding of NBS functioning and service delivery considering the impacts of climate change and of other sociodemographic and economic pressures
Keywords: nature-based solution, green infrastructure, urban morphology, sustainable urban development, green transition, ecosystem service, ecosystem disservice
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.