Nature-based solutions and urban planning in the Global South: Challenge orientations, typologies, and viability for cities

Urban Nature-based Solutions (NBS) are increasingly employed in research and practice to address the pressing environmental, social and economic challenges affecting cities. Nonetheless, there is a noticeable lack of an overview of the scholarship on the use of NBS in the Global South (GS) focusing especially on urban contexts, even though GS cities face unique socio-ecological challenges that could be addressed with NBS, as cost-effective and sustainable alternatives to grey infrastructural interventions. Through a systematic literature review, this article aims to examine the extent to which NBS are discussed in academic literature regarding the GS. The results show that NBS in the GS are mobilised especially to address two cross-cutting issues: rapid urbanization and informal settlements, and the impacts of climate change. NBS actions are explored both to incorporate nature into the urban environment and to "re-naturalise" existing urban areas. Water-related NBS types are the most numerous, and some research gaps highlighted are the need to further explore NBS for food safety and the lack of sufficient emphasis on reducing the Urban Heat Island effect (UHI), emphasising the importance of considering the social and economic context for the inclusion of NBS in the urban policy agenda. In terms of challenges related to the implementation and the mainstreaming of NBS adoption in urban agendas, the research highlights the problems of awareness, information accessibility, and financial sustainability. Finally, the review also raises the question of the involvement of external actors, while stressing the need to balance this involvement to avoid undermining local institutional capacity and public sector participation in the planning and implementation of NBS.