Misperceptions of Predominant Slum Locations? Spatial Analysis of Slum Locations in Terms of Topography Based on Earth Observation Data

Inken Müller,Hannes Taubenböck,Michael Wurm,Monika Kuffer

doi:10.3390/rs12152474

Inken Müller, Hannes Taubenböck + Show 2 more

Open Access

https://doi.org/10.3390/rs12152474

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Journal: Remote sensing	Publication Date: Aug 1, 2020
Citations: 19	License type: CC BY 4.0

Affiliation: German Aerospace Center, University of Twente

Abstract

Slums are a physical expression of poverty and inequality in cities. According to the UN definition, this inequality is, e.g., reflected in the fact that slums are much more often located in hazardous zones. However, this has not yet been empirically investigated. In this study, we derive proxies from multi-sensoral high resolution remote sensing data to investigate both the location of slums and the location of slopes. We do so for seven cities on three continents. Using a chi-squared test of homogeneity, we compare the locations of formal areas with that of slums. Contrary to the perception indirectly stated in the literature, we find that slums are in none of the sample cities predominantly located in these exposed areas. In five out of seven cities, the spatial share of slums on hills steeper than 10° is even less than 5% of all slums. However, we also find a higher likelihood of slums occurring in these exposed areas than of formal settlements. In six out of seven sample cities, the probability that a slum is located in steep areas is higher than for a formal settlement. As slums mostly feature higher population densities, these findings reveal a clear tendency that slum residents are more likely to settle in exposed areas.

Highlights

100,000 people were affected by debris flows and landslides caused by rain-induced floods in Venezuela in 1999
We found that the cumulative share of morphological slums is relatively low at 6.94% of the built-up area of all cities (322,017 ha)
A comparison of the percentages in the individual cities shows that the share of morphological slums varies from 1.8% in Cape Town to 20.9% in Caracas (Figure 7)

Summary

Introduction

100,000 people were affected by debris flows and landslides caused by rain-induced floods in Venezuela in 1999. As the example above drastically shows, low-income groups are often pushed into these hazardous locations, as this land, unsuitable for settlement, is often not occupied and the only one affordable [3,4]. Areas of low economical value tend to be less suitable for human settlements and are often the only spaces available and affordable for low income groups [7]. This effect becomes severe and is threatening the life of the poor when it comes to the exposure to hazards such as landslides, as they are one of the most destructive dangers in terms of death toll [8]. The poor, as the most vulnerable group in society, are as a consequence more likely to live in the most hazard-prone areas [3], which is called “land unwanted by others” [9]

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