This paper proposes a methodology for the analysis of social vulnerability to floods based on the integration and weighting of a range of exposure and resistance (coping capacity) indicators. It focuses on the selection and characteristics of each proposed indicator and the integration procedure based on the analytic hierarchy process (AHP) on a large scale. The majority of data used for the calculation of the indicators comes from open public data sources, which allows the replicability of the method in any area where the same data are available. To demonstrate the feasibility of the method, a study case is presented. The flood social vulnerability assessment focuses on the municipality of Ponferrada (Spain), a medium-sized town that has high exposure to floods due to potential breakage of the dam located upstream. A detailed mapping of the social vulnerability index is generated at the urban parcel scale, which shows an affected population of 34,941 inhabitants. The capability of working with such detailed units of analysis for an entire medium-sized town provides a valuable tool to support flood risk planning and management.
To increase the resilience of communities against floods, it is necessary to develop methodologies to estimate the vulnerability. The concept of vulnerability is multidimensional, but most flood vulnerability studies have focused only on the social approach. Nevertheless, in recent years, following seismic analysis, the physical point of view has increased its relevance. Therefore, the present study proposes a methodology to map the flood physical vulnerability and applies it using an index at urban parcel scale for a medium-sized town (Ponferrada, Spain). This index is based on multiple indicators fed by geographical open-source data, once they have been normalized and combined with different weights extracted from an Analytic Hierarchic Process. The results show a raster map of the physical vulnerability index that facilitates future emergency and flood risk management to diminish potential damages. A total of 22.7% of the urban parcels in the studied town present an index value higher than 0.4, which is considered highly vulnerable. The location of these urban parcels would have passed unnoticed without the use of open governmental datasets, when an average value would have been calculated for the overall municipality. Moreover, the building percentage covered by water was the most influential indicator in the study area, where the simulated flood was generated by an alleged dam break. The study exceeds the spatial constraints of collecting this type of data by direct interviews with inhabitants and allows for working with larger areas, identifying the physical buildings and infrastructure differences among the urban parcels.
The Sierra Minera de Cartagena-La Unión, located in southeast of the Iberian Peninsula, has been significantly impacted by historical mining activities, which resulted in environmental degradation, including acid mine drainage (AMD) and heavy metal contamination. This study evaluates the potential of PRISMA hyperspectral imagery for multi-temporal mapping of AMD-related minerals in two mining-affected drainage basins: Beal and Gorguel. Key minerals indicative of AMD—iron oxides and hydroxides (hematite, jarosite, goethite), gypsum, and aluminium-bearing clays—were identified and mapped using band ratios applied to PRISMA data acquired over five dates between 2020 and 2024. Additionally, Sentinel-2 data were incorporated in the analysis due to their higher temporal resolution to complement iron oxide and hydroxide evolution from PRISMA. Results reveal distinct temporal and spatial patterns in mineral distribution, influenced by seasonal precipitation and climatic factors. Jarosite was predominant after torrential precipitation events, reflecting recent AMD deposition, while gypsum exhibited seasonal variability linked to evaporation cycles. Goethite and hematite increased in drier conditions, indicating transitions in oxidation states. Validation using X-ray diffraction (XRD), laboratory spectral curves, and a larger time-series of Sentinel-2 imagery demonstrated strong correlations, confirming PRISMA’s effectiveness for iron oxides and hydroxides and gypsum identification and monitoring. However, challenges such as noise, striping effects, and limited image availability affected the accuracy of aluminium-bearing clay mapping and limited long-term trend analysis.
This research presents a renewable energy system that takes advantage of the energy potential available in the territory. This study emerges as a relevant option to provide solutions to geological risk areas where there are buildings that, due to emergency situations at certain times of the year during deep winter, are a target of danger and where its inhabitants would find it difficult to abandon their properties. The record of mass movements covering the city of Cuenca-Ecuador and part of the province has shown that the main triggering factor of this type of movement comprises the geological characteristics of tertiary formations characterized by lithological components that become unstable in the presence of water and due to their slopes being pronounced. Hybrid systems are effective solutions in distributed electricity generation, especially when it comes to helping people and their buildings in times of great need and the required electricity generation is basic. A hybrid photovoltaic, wind and hydrokinetic system has been designed that supplies electrical energy to a specific area on the opposite geographical side that is completely safe. The renewable energy system is connected to the public electricity grid available on site; however, in the event of an emergency the grid is disconnected for safety and only the hybrid system will work with the support of a battery backup system. In this study, the Homer Pro simulation tool was used and its results indicate that renewable systems that include PV, HKT and WT elements are economically viable, with a COE of USD 0.89/kWh.
9 January 2023 in European Journal of Soil Science
Torrential rainfall regimes, among others, are the origin of accelerated soil erosion. The Spanish southeastern Mediterranean region is characterised by an arid climate regime affected by extreme erosion episodes with an important loss of sediments. Soil erosion effects are even more noticeable in areas where soil has been anthropically degraded, as in the mining district of Sierra Minera de Cartagena . The present research focuses on monitoring and mapping the changes in the sediment distribution of iron oxides and hydroxyl (OH − ) bearing minerals caused by a cold drop known in Spanish as 'DANA' in September 2019 on the Rambla del Beal . This short rambla is fed by sediments from its drainage basin and by mining residues, irrigating a wide agricultural area. When discharges overflow the rambla channel, residues spread over its floodplain and reach the ecological protected coastal lagoon Mar Menor . The objective of the study was mapping the mineral distribution of the mining materials eroded from the source areas and sedimented in Rambla del Beal during a DANA. The study was carried out using a pre‐ and a post‐DANA image from the Sentinel‐2 satellite. After masking vegetation, urban areas and water bodies, different band ratios (B4/B3, B11/B12, B8A/B6) and a Spectral Angle Mapper (SAM) classification were applied. Sediment deposits were identified in wider areas after the DANA. Iron oxides increased their extension by 11.08% in the central area (B3/B4 with R 2 of 0.84) and hydroxyl‐bearing minerals increased by 8.95% in the Rambla del Beal 's headwaters (B11/B12 with R2 of 0.71). The SAM classification (with a 0.1 rad threshold and an overall accuracy of 87.33%) allowed the differentiation and classification of two ferric iron oxides (haematite and goethite) and one iron hydrous sulphate mineral (jarosite). Additionally, band ratio images were spatially overlaid with the soil land uses map layer of the cadastre in order to plot the land uses most affected by the transported sediments during the DANA. These results highlighted agricultural land as the areas (land uses) most affected by iron oxides deposition, as oxidation processes occur more rapidly in these areas. However, grassland and scrubland were the areas with the highest content of hydroxyl‐bearing minerals, as water is accumulated in these places, which favours hydrolysis reactions. Highlights: Torrential events can relocate large volumes of contaminated sediments from former mining areas. Sentinel‐2 allows monitoring mine waste iron‐sulphate changes caused by weathering alteration. Spatial mineralogical pattern in sediments is controlled by geomorphology and flood dynamics. The proposed digital image analysis allows mapping short‐term evolution of mine waste sediments.