Linking Urban Marginality and Socio-Ecological Systems to Highlight Research Areas in Informal Settlements Upgrading: a Literature Review and Future Directions

Slums are basically recognized as a multi-causality phenomenon which is rapidly growing worldwide. While the contribution of social and ecological factors is separately well understood, the interplay of interconnected socio-ecological systems in slums, such as urban heat islands, is insufficiently addressed in research. This study identifies the most important socio-ecological research areas applicable in analyzing slum settlements by using a narrative literature review method. This type of review was applied to clarify an overview of knowledge regarding the linkage between socio-ecological perspectives and informal settlements. Further, it advances the definition and the reasons behind slum shaping. The results of this study show that there are particularly three main research areas including: urban sustainability and metabolism, climate change, and ecosystem services for slum analysis in the literature. Exploring the gaps through a slum socio-ecological research framework paves the way for studying further research. We also highlighted the need for analyzing energy efficiency and flows, application of renewable energies, drought dynamics, biodiversity services and urban heat islands more than other possible subjects for future directions in slum socio-ecological research.