Assessment of the performance of X-band satellite radar data for landslide mapping and monitoring: Upper Tena Valley case study.

Abstract. The aim of this work is to analyse the advantages and disadvantages of using the new X-band SAR data acquired by TerraSAR-X sensors for landslides mapping. This dataset has been processed using a Persistent Scatterer Interferometry technique over the Upper Tena Valley (Central Pyrenees, Spain). In the first section, the geological and geomorphological setting of the study area is introduced, focusing on the description of the landslide inventory. Then the Stable Point Network technique is briefly described, followed by the assessment of the performance of the X-band SAR dataset. In this context, we present first a model to predict the distribution of Persistent Scatterers based on the slope geometry and the land use information, which has then been validated with X-band data results. On a second stage, we have assessed the performance of X-band dataset to detect and monitor mapped landslides. Finally some illustrative case studies are shown demonstrating the potential of using X-band SAR data not only for landslide mapping but also to detect and monitor deformations affecting human infrastructures

Mapping and monitoring geomorphological processes in mountainous areas using PSI data: Central Pyrenees case study

In this paper the Stable Point Network technique, an established Persistent Scatterer InSAR (PSI) technique, (SPN), has been applied for the first time to the analysis of several geomorphological processes present in the Gállego river basin (Central Pyrenees, Spain). The SPN coherence based approach has been used to process three different SAR images datasets covering two temporal periods: 1995 to 2001 and 2001 to 2007. This approach has permitted the detection of more than 40 000 natural ground targets or Persistent Scatterers (PSs) in the study area, characterised by the presence of vegetation and a low urban density. Derived displacement maps have permitted the detection and monitoring of deformations in landslides, alluvial fans and erosive areas. In the first section, the study area is introduced. Then the specifics of the SPN processing are presented. The deformation results estimated with the SPN technique for the different processed datasets are compared and analysed with previous available geo-information. Then several detailed studies are presented to illustrate the processes detected by the satellite based analysis. In addition, a comparison between the performance of ERS and ENVISAT satellites with terrestrial SAR has demonstrates that these are complementary techniques, which can be integrated in order to monitor deformation processes, like landslides, that over the same monitoring area may show very different ranges of movement. The most relevant conclusions of this work are finally discussed

Anthropic resource exploitation and use of the territory at the onset of social complexity in the Neolithic-Chalcolithic Western Pyrenees: a multi-isotope approach

Carbon (δ13C) and nitrogen (δ15N) stable isotope analyses from bone collagen provide information about the dietary protein input, while strontium isotopes (87Sr/86Sr) from tooth enamel give us data about provenance and potential territorial mobility of past populations. To date, isotopic results on the prehistory of the Western Pyrenees are scarce. In this article, we report human and faunal values of the mentioned isotopes from the Early-Middle Neolithic site of Fuente Hoz (Anuntzeta) and the Late Neolithic/Early Chalcolithic site of Kurtzebide (Letona, Zigoitia). The main objectives of this work are to analyze the dietary and territorial mobility patterns of these populations. Furthermore, as an additional aim, we will try to discuss social ranking based on the isotope data and existing literature on this topic in the region of study. Our results show that, based on the bioavailable Sr values, both purported local and non-local humans were buried together at the sites. Additionally, they suggest similar resource consumption based on C3 terrestrial resources (i.e. ovicaprids, bovids, and suids) as the main part of the protein input. Overall, this study sheds light on how individuals from different backgrounds were still buried together and shared the same dietary lifestyle at a time in the Prehistory of Iberia when social complexities started to appear

Producción de proteína microbiana a partir de los desechos del procesamiento de la caña de azúcar (bagacillo)(Microbial protein production from waste of sugar cane processing (bagasse pith))

A study was undertaken of microbial biomass production using hydrolyzed pith bagasse acid as a growth medium. Hydrolysis was carried out using diluted (6%v/v) sulfuric acid in a reaction time of four hours. The equipment used operated at boiling conditions with atmospheric pressure reflux, and with a liquid/solid relation of 30. The concentration of sugars in the hydrolyzed solution was carried out by a rotational evaporator. The Candida utilis (ATCC 9256) and Saccharomyces cerevisiae (ATCC 26603) yeasts were cultivated in the hydrolyzed concentrate at a pH of 5.00, 30 °C and 200 rpm. The greatest production of biomass was 4.90 ± 0,03 kg/m3 in S. cerevisiae and 9.45 ± 0,01 kg/m3 in C. utilis. The yield of biomass was 1.19 ± 0,012 kg/kg in S. cerevisiae and 1.86 ± 0,040 kg/kg in C. utilis. The specific rate of growth was 0.0141 ± 0,0001 and 0.0544 ± 0,0001 h-1 for S. cerevisiae and C. utilis, respectively. The biotechnological process utilized is an important fundamental alternative for the industrial usage of pith bagasse from sugar cane through the production of a protein concentrate for animal feeds

Site scale modeling of slow-moving landslides, a 3D viscoplastic finite element modeling approach

This paper presents an advanced 3D numerical methodology to reproduce the kinematics of slow active landslides, more precisely, to reproduce the nearly constant strain rate (secondary creep) and the acceleration/deceleration of the moving mass due to hydrological changes. For this purpose, finite element analyses are performed in a large area covering a long time-span (12 years), in order to exhibit different interacting slope movements. First, we perform a stability analysis using the shear strength reduction (SSR) technique with a Mohr-Coulomb failure criteria. It is done in order to compute factors of safety (FS) and to identify two different scenarios, the first one being stable (FS > 1) and the second one being unstable (FS < 1). In the studied test case, the Portalet landslide (Central Spanish Pyrenees), the first scenario corresponds to an initial stable configuration of the slope and the second one to an unstable excavated configuration. Second, taking the first scenario as an initial condition, a time-dependent analysis is performed using a coupled formulation to model solid skeleton and pore fluids interaction, and a simplified ground water model that takes into account daily rainfall intensity. In this case, a viscoplastic constitutive model based on Perzyna’s theory is applied to reproduce soil viscous behavior and the delayed creep deformation due to the excavation. The fluidity parameter is calibrated to reproduce displacements measured by the monitoring systems. Our results demonstrate that 3D analyses are preferable to 2D ones for reproducing in a more realistic way the slide behavior. After calibration, the proposed model is able to simulate successfully short- and medium-term predictions during stages of primary and secondary creep.This research has been supported by the Spanish Ministry of Economy and Competitiveness grants ESP2013-47780-557 C2-1-R and ESP2013-47780-557 C2-2-R. It is a contribution to the Moncloa Campus of International Excellence.Peer reviewe

A methodology for improving landslide PSI data analysis

In this work, we present a methodology for improving persistent scatterer interferometry (PSI) data analysis for landslide studies. This methodology is a revision of previously described procedures with several improved and newly proposed aspects. To both evaluate and validate the results from this methodology, we used various persistent scatterer (PS) datasets from different satellites (ERS – ENVISAT, Radarsat, TerraSAR-X, and ALOS PALSAR) that were processed using three PSI techniques (stable point network – SPN, permanent scatterer interferometry – PSInSAR™, and SqueeSAR™) to map and monitor landslides in various mountainous environments in Spain and Italy. This methodology consists of a preprocessing model that predicts the presence of a PS over a certain area and a post-processing method used to determine the stability threshold, project the line of sight (LOS) velocity along the slope, estimate the E–W and vertical components of the velocity, and identify anomalous areas

Points and areas prone to earthquake-induced landslides in the CARM. Base information for Civil Protection

Se presenta un trabajo de aplicación para la definición de posibles escenarios de catástrofe sísmica, donde deben de incorporarse los movimientos de ladera, como información de base para la última revisión del Plan Especial de Protección Civil ante el Riesgo Sísmico en la Región de Murcia (SISMIMUR). Para ello se ha confeccionado un inventario adecuado y un mapa a escala 1:200.000 que contiene los puntos y zonas más susceptibles a este tipo de fenómenos inducidos por los terremotos en la CARM que pueden afectar a núcleos urbanos, infraestructuras lineales (carreteras y ferrocarriles), balsas mineras, cursos de agua y cuerpos de agua (embalses y lagos). En el análisis solo se han seleccionado los puntos definidos como desprendimientos s.l., tipología predominante en la zona de estudio y de mayores efectos de cara al escenario de la catástrofe sísmica posible. Aunque la mayoría de las infraestructuras evaluadas están alejadas de movimientos de ladera inventariados, hay núcleos de población importantes como Lorca, Águilas o Caravaca de la Cruz, entre otras, así como algunos tramos del creciente entramado urbano del litoral murciano con zonas de susceptibilidad alta. El tramo más susceptible sería el situado en la carretera RM-520, entre Archena y AbaránIn this work, we present a methodology to define potential seismic scenarios incluiding seismic-induced landslides as background information for the latest revision of the “Plan Especial de Protección Civil ante el Riesgo Sísmico en la Región de Murcia (SISMIMUR)”. We first made an adequate inventory and a map at 1:200,000 scale containing the points and areas more susceptible to this type of seismic-induced effects in the CARM which may affect urban areas, lifelines(roads and railways), tailing dams, waterways and bodies of water (reservoirs and lakes). For this analysis, only points defined as rockfalls s.l. have been selected, since they are the predominant type of landslide in the area and it is associated to the greatest effects regarding a potential seismic scenario. Although most of the infrastructures evaluated are far from the inventoried landslides, some areas with high susceptibility have been identified near major population centers, such as Lorca, Águilas, Caravaca de la Cruz, etc., and near of some growing urban fabric areas located along the Murcia province coast. According to this study, the most vulnerable section would be located in the RM-520 road between Archena and Abarán.Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEpu

Analysis of SAR-derived products to support emergency management during volcanic crisis: La Palma case study

International audienceThis paper analyses the performance of SAR-based results to support emergency management operations during the volcanic crisis of La Palma island. Tajogaite eruption began on September 19th 2021 affecting a high populated area and the surrounding farmland, used for different agricultural purposes. SAR datasets obtained from Sentinel-1, COSMO-SkyMED, PAZ-TerraSAR-X and Capella satellites, were processed to calculate amplitude, coherence and differential interferograms. These results have permitted to map the morphology of the volcanic cone, the evolution of lava flows and the regional displacements. The comparison of the results obtained with the different satellites has been useful to understand their performance during an emergency scenario triggered by a volcanic eruption. COSMO-SkyMED has provided the most useful information for the analysis of the cone morphology and the lava flows. Sentinel-1 showed the best performance for regional displacements monitoring, whereas PAZ results was the second best option for all the retrieved products