Combining Social Vulnerability and Physical Vulnerability to Analyse Landslide Risk at the Municipal Scale

Abstract

In this work residents’ social vulnerability and buildings’ physical vulnerability of the Loures municipality (Portugal) were combined to locate the areas where the vulnerability is the highest, and to analyse the landslide risk. The social vulnerability of Loures was assessed using the Geographic Basis for Information Reference (BGRI) terrain units by combining sensitivity and lack of resilience based on the population and housing Census 2011 data. The physical vulnerability was assessed in a previous study based on an inquiry of a pool of European landslide experts and a sub-pool of landslide experts who know the study area. A matrix approach was used to cross the classes of the social and physical vulnerabilities. Finally, the landslide risk was analysed for each terrain unit considering the combined vulnerability, the buildings’ economic value and the landslide susceptibility for a specific landslide magnitude (3-metre-deep rotational slide). Results show that 0.9% of the population reside in the area of the municipality where 75% of the future landslide should occur, and 0.8% of the buildings of the municipality—which represent a value of EUR 146,170,000—are also located in this dangerous area. This approach is reproducible: the risk analysis can be applied for another magnitude scenario in Loures, and the combined vulnerability can be assessed in any Portuguese municipality thanks to the availability of the data.

From Multi-Risk Evaluation to Resilience Planning: The Case of Central Chilean Coastal Cities

“…It is worth noting that, although vulnerability definitions normally acknowledge its multi-dimension and site-specific nature [80], most of the scientific studies explore only one of the dimensions of vulnerability of the elements at risk (either the social or physical dimension). Both together, as it is in the case of our study, are rarely considering in the literature [76].…”

“…Vulnerability refers to the susceptibility of a community or system of being negatively impacted by a hazard [75,76]. Based upon the results of technical studies developed by the UNESCO-RAPCA (Regional Action Program Central America) project, which since 1999 has been working on the use of GIS and remote sensing tools to assess the impact of natural hazard on human and physical infrastructure in Latin America [77], vulnerability of three components were assessed: housing, facilities (i.e., public and private buildings, equipment, and services) and infrastructure.…”

“…The physical vulnerability refers to the susceptibility of an element to suffer physical damage because of a hazard. On the other hand, although the socio-economic vulnerability is generally defined as the predisposition of social groups in the context of a natural disaster [78,79], the concept has multiple and complex different definitions [76]. In this study, the socio-economic vulnerability refers to the capacity to respond to a hazard given its relevance and hierarchy in the system [75], which are proxies of the intangible losses of elements at risk in society.…”

A hybrid model using data mining and multi-criteria decision-making methods for landslide risk mapping at Golestan Province, Iran

“…Specifically, an additional mapthe landslide vulnerability mapwhich describes the potential landslide damage on local population, property, infrastructure, and public services, is required. This vulnerability map constitutes the second step toward landslide risk assessment (Guillard-Gonçalves & Zêzere 2018). By suitably combining the vulnerability map with the hazard map, a landslide risk map can be obtained, which provides a joint probabilistic assessment of damaging landslide occurrence and the concatenated socioeconomic impacts (Frigerio & Amicis, 2016;Murillo-García et al 2017;Guillard-Gonçalves & Zêzere, 2018).…”

“…and social vulnerability must be modeled. Indeed, the concept of social vulnerability refers, in a broad sense, to personal injuries and impact of a damaging landslide on different socio-economical groups, but still lacks common definition (Guillard-Gonçalves & Zêzere, 2018). Furthermore, various aspects of social vulnerability relate to potential material losses in the private and public sectors as well, and it is, thus, difficult to mathematically treating social vulnerability by excluding the physical aspect of vulnerability.…”