Publications
Publications found: 811
Country Report_ Italy – 31st Session FAO EFC WPMMW – Prague (Czech Republic), 4-6 September 2017
Piermaria Corona, Roberto Tognetti, Lorenzo Marchi, Flavia Tauro, 2017, Country Report_ Italy – 31st Session FAO EFC WPMMW – Prague (Czech Republic), 4-6 September 2017,
2017,
Abstract
The first part of the report summarises the most important features of mountain watersheds in ...
The first part of the report summarises the most important features of mountain watersheds in Italy, with regard to the evolution of land use, the impact of geo-hydrological hazards in the mountain territory, and the ecosytem services of mountain forests. The second and third sections of the document describe the project aimed at the study of mountain watersheds and relevant events (workshops, courses, etc.) implemented in the last two years in Italy.
Characteristics of rainfall responsible for debris flows in Wenchuan Earthquake area
Guo X.; Cui P.; Marchi L.; Ge Y., 2017, Characteristics of rainfall responsible for debris flows in Wenchuan Earthquake area,
Environmental earth sciences (Print) 76 (2017). doi_10.1007/s12665-017-6940-y,
DOI: 10.1007%2Fs12665-017-6940-y
Abstract
The ability to forecast debris flows is important because of their frequent occurrence and potential ...
The ability to forecast debris flows is important because of their frequent occurrence and potential for large-scale damage in the Wenchuan Earthquake-hit area. Accurate understanding of the characteristics of rainfall responsible for triggering debris flows is necessary for an effective early warning procedure. This study examined the general characteristics and spatiotemporal variation of rainfall events that responsible for debris flows. Analysis was performed on rainfall data extracted during 2008-2013. The results revealed that the rainfall thresholds for debris flows varied annually and showed tendency toward higher conditions required. The coefficient of variation of relevant rainfall events indicated that the characteristics of the rainstorms changed. In addition, the coefficient of deviation revealed the spatial variation of rainfall in subregions, which was attributed to differences of the local climatic conditions that control debris flow occurrence. The primary controlling rainfall indices for triggering debris flows were filtered, and the most suitable models for establishing rainfall thresholds were selected. Ultimately, the rainfall thresholds were obtained for each subregion within the study area.
A Review of Distributed Fibre Optic Sensors for Geo-Hydrological Applications
Luca Schenato, 2017, A Review of Distributed Fibre Optic Sensors for Geo-Hydrological Applications,
Applied sciences 7 (2017): 1–42. doi_10.3390/app7090896,
DOI: 10.3390%2Fapp7090896
Abstract
Distributed optical fibre sensing, employing either Rayleigh, Raman, or Brillouin scattering, is the only physical-contact ...
Distributed optical fibre sensing, employing either Rayleigh, Raman, or Brillouin scattering, is the only physical-contact sensor technology capable of accurately estimating physical fields with spatial continuity along the fibre. This unique feature and the other features of standard optical fibre sensors (e.g., minimal invasiveness and lightweight, remote powering/interrogating capabilities) have for many years promoted the technology to be a promising candidate for geo-hydrological monitoring. Relentless research efforts are being undertaken to bring the technology to complete maturity through laboratory, physical models, and in-situ tests. The application of distributed optical fibre sensors to geo-hydrological monitoring is here reviewed and discussed, along with basic principles and main acquisition techniques. Among the many existing geo-hydrological processes, the emphasis is placed on those related to soil levees, slopes/landslide, and ground subsidence that constitute a significant percentage of current geohazards.
The Vajont Valley (Eastern Alps): A Complex Landscape Deeply Marked by Landsliding
Alessandro Pasuto, 2017, The Vajont Valley (Eastern Alps): A Complex Landscape Deeply Marked by Landsliding,
Landscapes and Landforms of Italy, edited by Soldai, Mauro e Marchetti, Mauro, pp. 135–145, 2017,
Abstract
On 9th October 1963 the Vajont Valley was strongly modified due to a world known
landslide, ...
On 9th October 1963 the Vajont Valley was strongly modified due to a world known
landslide, which claimed the lives of almost 2000 people. At that time a huge amount of
material collapsed into an artificial reservoir generating a water wave, which overtopped the
dam destroying seven villages in the Piave River Valley. The landslide accumulation filled
the valley blocking its drainage that is now guaranteed by a by-pass built soon after a
previous smaller landslide occurred on 4th November 1960. However, the whole valley has
been affected by a series of landslides, which buried ancient glacial and fluvial landforms
sealing and preserving them. The chapter is therefore not only focusing on the Vajont
Landslide, but also on other gravitational, glacial and fluvial landforms, which are crucial
for the reconstruction of the post-glacial geomorphological evolution.
Testing the potential of Sentinel-1A TOPS interferometry for the detection and monitoring of landslides at local scale (Veneto Region, Italy)
Fiaschi, S. and Mantovani, M. and Frigerio, S. and Pasuto, A. and Floris, M., 2017, Testing the potential of Sentinel-1A TOPS interferometry for the detection and monitoring of landslides at local scale (Veneto Region, Italy),
Environmental earth sciences (Internet) 76 (2017): 492. doi_10.1007/s12665-017-6827-y,
DOI: 10.1007%2Fs12665-017-6827-y
Abstract
The recent Sentinel-1 mission, started by the European Space Agency in April 2014, provides the ...
The recent Sentinel-1 mission, started by the European Space Agency in April 2014, provides the scientific community with new capabilities for the monitoring of the Earth surface. In particular, the Terrain Observation by Progressive Scans imaging technique used in the Interferometric Wide swath acquisition mode permits to acquire data over very wide areas (250?km of swath extension) at 20-m spatial resolution, with 12-day revisit time, making it suitable for ground displacement monitoring applications. With more than 1?year of synthetic aperture radar images available, it is now possible to carry out monitoring activities of slow moving phenomena such as landslides at both regional and local scales. In this work, the potential of Sentinel-1A for the monitoring of shallow (from 2 to 6?m of depth) landslides occurring in the North-Eastern Italian Pre-Alps was tested. Two stacks of Sentinel-1A scenes acquired in both ascending and descending orbits were processed using the Permanent Scatterer Interferometry (PSI) technique. The results, analysed in terms of PS density and quality, were compared with the ERS-1/2 and ENVISAT PSI database available from the Italian National Cartographic Portal to assess the capabilities of Sentinel-1A in detecting and monitoring landslides in respect to the previous satellite missions. The results of this work show the great potential of Sentinel-1A in the continuous monitoring of landslide-prone territories even at local scale. The achievable results can provide information that is useful to delineate the spatial and temporal evolution of landslides and precisely assess their rates of deformation.
Geomorfometria per la caratterizzazione della connettività del sedimento e delle variazioni geomorfologiche nei bacini montani
Cavalli M., 2017, Geomorfometria per la caratterizzazione della connettività del sedimento e delle variazioni geomorfologiche nei bacini montani,
Giornata di studio AIGEO - Università La Sapienza "Monitoraggio e valutazione dei processi erosivi", Roma, 22/06/2017,
Abstract
Presentazione su invito alla Giornata di studio AIGEO - Università La Sapienza "Monitoraggio e valutazione ...
Presentazione su invito alla Giornata di studio AIGEO - Università La Sapienza "Monitoraggio e valutazione dei processi erosivi"
Geomorphometric approaches to assess sediment connectivity in mountain catchments
Cavalli M., 2017, Geomorphometric approaches to assess sediment connectivity in mountain catchments,
Workshop Italy-Chile CONICYT project "Natural Risks in Mountain Areas and their Effects in River Morphology", Legnaro, Agripolis (PD), 21/05/2017,
Abstract
Invited talk nell'ambito del Workshop Italy-Chile CONICYT project "Natural Risks in Mountain Areas and their ...
Invited talk nell'ambito del Workshop Italy-Chile CONICYT project "Natural Risks in Mountain Areas and their Effects in River Morphology"
Comparing the effectiveness of image inpainting techniques over standard interpolation procedures for high-resolution data analysis
Crema S., Marchi L., Cavalli M., 2017, Comparing the effectiveness of image inpainting techniques over standard interpolation procedures for high-resolution data analysis,
12 Convegno GIT - Geology and Information Technology, Gavorrano (GR), 12-14/06/2017,
Abstract
The increasing availability of high-resolution Digital Terrain Models (DTMs) in recent years represents a great ...
The increasing availability of high-resolution Digital Terrain Models (DTMs) in recent years represents a great opportunity for Geosciences being this input information a fundamental prerequisite for an accurate representation of the surface and of the processes acting on it.
Nowadays, a number of techniques in order to produce high-resolution DTMs are available. Depending on the scale of analysis, the most used survey techniques are_ i) Radar, ii) LiDAR and iii) Photogrammetry. The raw survey-derived products are often in need of a careful post-processing in order to filter out unwanted features. This, for example, could be the case of vegetation removal for surface processes modeling. After the filtering procedures, usually either the point density under filtered areas drops down or missing data areas are created. Resulting interpolated surfaces, in particular over these areas, could vary significantly, mainly depending on the selected interpolation algorithm, sometimes leading to the creation of artifacts that are not able to mimic the original surface trend and texture. In this work, we devised an experiment in order to compare the results of an image inpainting technique over missing data holes against commonly used interpolators (IDW, Spline, Kriging, Natural Neighbor) quantifying the accuracy of the approaches. The image inpainting technique has demonstrated in all the cases a significantly better performance in reconstructing the original surface. An assessment of the extent up to which such an approach could be regarded as robust has also been carried out. Selected applications of surface propagation models to the reconstructed surfaces have been reported so as to highlight how surface variability and uncertainty in surface reconstruction can influence (positively/negatively) model results.
Applications of such an approach could pave the way for accurate surface interpolation and/or surface reconstruction in case of the need to remove selected features to characterize several modeling scenarios or to fill the gaps to reproduce the original surface in a consistent way.
Assessing the effect of land use changes on sediment connectivity for landslides runout characterization
Persichillo M.G., Crema S., Bordoni M., Meisina C., Cavalli M, 2017, Assessing the effect of land use changes on sediment connectivity for landslides runout characterization,
12 Convegno GIT - Geology and Information Technology, Gavorrano (GR), 12-14/06/2017,
Abstract
The study of a landslide runout (i.e., the distance traveled by sediment detached by a ...
The study of a landslide runout (i.e., the distance traveled by sediment detached by a landslide) is fundamental for a comprehensive understanding of the risk associated with landslide occurrence since sediment mobilized from landslides can often reach downstream areas causing extensive damages.
The spatial characterization of sediment dynamics through geomorphic systems (i.e., sediment connectivity) is a key property to define sediment transfer paths.
Sediment connectivity is mainly controlled by the morphological complexity of the catchment and the spatial organization of vegetation. In particular, vegetation plays an important role on sediment connectivity, since it influences surface roughness and local sediment retention capacity. Moreover, vegetation changes due to land use and management practice modifications can introduce major changes in sediment delivery dynamics, leading to important effects on earth surface processes, especially in relation to slope instability phenomena.
Within this framework, the aim of this work is to evaluate how vegetation characteristics and its modifications over time can affect sediment connectivity in response to shallow landslides occurrence.
A GIS-based index of connectivity (IC) was computed for a hilly catchment located in the northern Apennines in Italy. This area was characterized by a high degree of land abandonment, leading to important landscape modifications over the last 60 years. Moreover, the studied catchment was highly affected by shallow landslide phenomena, mainly triggered by an intense rainfall event in 2009.
Land use changes characterizing the study area in the last 60 years were integrated into IC computation. The Overland Flow Manning's n Roughness Values was used in order to represent the impedance to water and sediment fluxes related to each land use class. This parameter was integrated into a revised version of IC weighting factor (W). In particular, both a linear e non-linear relationship for the Manning's n based W was computed. This allowed integrating the hydraulic efficiency of overland runoff flow in the analysis framework.
Finally, the results of IC implementing the revised W, based on land use change dynamics, was integrated into a data-driven model to evaluate the probability that the sediments produced by instability phenomena could reach downstream areas. In particular, this analysis allowed identifying those areas in which the mobilized sediment could damage the road network blocking traffic, isolating villages and stopping activities.
Assessing the effects of changes on land cover on sediment connectivity by means of historical aerial photographs and digital photogrammetry
Llena M., Cavalli M., Vericat D., Crema S., Smith M., 2017, Assessing the effects of changes on land cover on sediment connectivity by means of historical aerial photographs and digital photogrammetry,
12 Convegno GIT - Geology and Information Technology, Gavorrano (GR), 12-14/06/2017,
Abstract
A significant number of mountain catchments have suffered important land use changes due to agricultural ...
A significant number of mountain catchments have suffered important land use changes due to agricultural abandonment during the second half of the 20th century. These changes do not only induced an increase in the vegetation cover but also a series of natural and anthropic morphological changes (e.g. terraces) that influence the water and sediment flux through catchments. In the present study the effect of these changes (i.e. land cover and topography) on sediment connectivity is analyzed in different scenarios of change in the Upper Cinca Basin (Southern Pyrenees).
Potential sediment connectivity can be assessed by a morphometric indicator named Index of Connectivity (IC) developed by Cavalli et al (2013) based upon the original approach by Borselli et al (2008). The input variables of IC are determined by the land use or landscape roughness, and topography. In this work we present a methodological workflow to obtain such variables from historical aerial photos using digital photogrammetry through Structure from Motion and Multi View Stereo algorithms (SfM-MVS). A prerequisite of the analysis is to reconstruct the land use and the landscape properties at the period in which the IC is estimated. The analysis consists of three interrelated steps_ (a) extraction of historical ortophotomaps and point clouds from historical photos (aerial photos from 1957 and 1977) using SfM-MVS, (b) derivation of land use maps and topographic models for those periods to parametrize IC, and (c) assessment and comparison of historical sediment connectivity in each period.
The workflow was tested in different contrasted sub-catchments representative of three main scenarios_ (1) Changes on land cover; (2) Topographic changes on agricultural fields (terracing); (3) Topographic changes associated to infrastructures (road construction). From the methodological point of view, results highlight as the selection of the suitable resolution of the Digital Elevation Models used in each scenario is crucial for the correct analysis of IC changes. Terraces affect connectivity in a major degree than land use changes, following a more spatially concentrated pattern, while the morphological variation due to road construction led to an increase of erosional activities uphill the road. In the light of these results, the developed workflow to assess sediment connectivity at multiple temporal scales has proved to be a promising and useful methodology to plan and asses potential risks associated to morphological and land use changes.
From SfM photogrammetry to DoDs_ a methodological workflow to monitor topographic changes in a debris-flow catchment
Cucchiaro S., Cavalli M., Vericat D., Crema S., Marchi L., Cazorzi F., 2017, From SfM photogrammetry to DoDs_ a methodological workflow to monitor topographic changes in a debris-flow catchment,
12 Convegno GIT - Geology and Information Technology, Gavorrano (GR), 12-14/06/2017,
Abstract
Debris-flow catchments are characterised by remarkable geomorphic changes that can occur with high frequency. Accordingly, ...
Debris-flow catchments are characterised by remarkable geomorphic changes that can occur with high frequency. Accordingly, monitoring topographic changes induced by these processes requires high-resolution surveys acquired with high frequency. Recent photogrammetric techniques, such as Structure from Motion (SfM) and Multi-View Stereo (MVS), represent a low-cost opportunity for acquiring multi-temporal high-resolution topography. However, these techniques need important steps of data processing and uncertainty analysis to identify and filter erroneous or unwanted data, that may have a significant effect on the estimates of topographic changes.
Within this context, in this paper we present a methodological and standardized workflow for_ i) data-acquisition and post-processing to obtain usable and accurate Digital Terrain Models (DTMs) and ii) error analysis to assess uncertainty in the study of topographic changes through DEM-differencing analysis (DEMs of Difference or DoD).
This workflow is based in the application of SfM and MVS techniques and was developed and tested in a small area of the Moscardo catchment (eastern Italian Alps). Multi-temporal SfM-MVS photogrammetry based on images taken from the ground and by means of UAV were carried out before and after three debris-flows occurred between June and July 2016. The developed workflow involves the following steps_ (a) point cloud generation through the application of SfM-MVS; (b) analysis of the precision and accuracy of the Ground Control Points (GCPs) and the resultant point clouds by means of Check Points (CPs); (c) data filtering, cleaning and decimation through geostatistical tools; (d) evaluation of the need to carry out the alignment of multi-temporal point clouds; (e) DTMs generation; (f) assessment of a minimum Level of Detection (minLoD) based on data precision; (g) DoDs preparation and thresholding based on the minLoD; (h) assessment of topographic changes.
Metodologia e strumenti per la raccolta dati e l’analisi dei processi torrentizi che interessano le aree di conoide nella Regione Veneto
Cavalli M., Crema S., Viero A., Arziliero L., Marchi L., 2017, Metodologia e strumenti per la raccolta dati e l’analisi dei processi torrentizi che interessano le aree di conoide nella Regione Veneto,
12 Convegno GIT - Geology and Information Technology, Gavorrano (GR), 12-14/06/2017,
Abstract
Il presente studio nasce dall'esigenza degli uffici della Regione Veneto di predisporre una procedura finalizzata ...
Il presente studio nasce dall'esigenza degli uffici della Regione Veneto di predisporre una procedura finalizzata alla valutazione della pericolosità sui conoidi alluvionali classificati come zone d'attenzione nei PAI Piave, Brenta-Bacchiglione e Livenza. Al fine di individuare un percorso oggettivo per la valutazione della pericolosità sono state identificate e proposte metodologie di raccolta dati e di analisi atte ad individuare la tipologia del processo da investigare distinguendo, in particolare, tra colate detritiche e piene con trasporto solido, essendo questa distinzione di fondamentale importanza al fine di orientare le successive analisi.
Nell'ambito dello studio sono stati sviluppati due strumenti per condurre e facilitare la raccolta dati del sistema bacino-conoide: i) una scheda, in formato digitale editabile, strutturata in diverse sezioni per la raccolta di una serie di informazioni che concorrono a caratterizzare oggettivamente la morfologia, la genesi, i processi attualmente attivi e lo stato di funzionamento del sistema bacino-conoide; ii) un database geografico delle aree di conoide che integra le informazioni riportate nelle schede e la documentazione su eventi storici reperita da diverse fonti documentarie.
Nell'ambito della procedura per la valutazione della pericolosità sono stati sviluppati diversi software liberamente disponibili per l'identificazione lungo il reticolo idrografico delle aree di potenziale innesco, rallentamento e deposito di colate detritiche e per il calcolo della distanza di arresto delle colate detritiche finalizzato all'assegnazione di una priorità d'indagine dei conoidi. Questi applicativi costituiscono un prezioso ausilio per condurre le analisi previste dalla procedura sviluppata. Il presente contributo presenta inoltre i risultati delle analisi in tre aree test situate nelle province di Vicenza, Treviso e Belluno.
Modeling Debris Flows in Anomalous Basin-Fan Systems
Erika de Finis, Paola Gattinoni, Lorenzo Marchi, Laura Scesi, 2017, Modeling Debris Flows in Anomalous Basin-Fan Systems,
4th World Landslide Forum, pp. 601–609, Ljubljana, 29/5/2017 - 2/6/2017,
Abstract
The paper proposes a modeling analysis of debris flows in anomalous basin-fan systems.
Previous studies pointed ...
The paper proposes a modeling analysis of debris flows in anomalous basin-fan systems.
Previous studies pointed out that the main geo-hydrological hazard in anomalous basin-fan
systems is really related to the occurrence of debris flows, favored by the presence of large
amount of loose debris on high slopes, which also favor the predominance of the
entrainment process in determining the magnitude of the events. Consequently, the
pseudo-3D model RAMMS DEBRIS FLOW was used in order to simulate the debris flow
dynamic in anomalous systems. At this aim, a back analysis was carried out on the debris
flow that occurred in July 2013 in the Gadria catchment (Val Venosta, northern Italy). This
event was characterized by a quite small source area located in the head zone of the basin,
whereas the volume that reached the basin outlet was quite large, because of entrainment
process. The frictional parameters were calibrated using the entrainment simulation,
obtaining values more similar to the ones typical of rock avalanches than the values
generally used for the simulation of debris flows.
Linking Debris Flows and Landslides to Large Floods in Gravel-Bed Rivers
Marchi L., 2017, Linking Debris Flows and Landslides to Large Floods in Gravel-Bed Rivers,
Gravel-bed Rivers - Processes and Disasters, edited by Tsutsumi D., Laronne J.B., pp. 467–495. Oxford_ Wiley-Blackwell, 2017,
Abstract
Landslides and debris flows are very effective geomorphic agents influencing the evolution of fluvial systems ...
Landslides and debris flows are very effective geomorphic agents influencing the evolution of fluvial systems in mountain catchments. The concurrence of landslides, debris flows and floods urges the development of methods that can cope with multiple hazards resulting from the interactions between these processes. This paper presents examples of relationships between landslides (including debris flows) and floods in gravel-bed rivers_ the occurrence of a large debris flow in a steep gravel-bed channel caused by the failure of landslide dams in an upstream channel reach, the increase of sediment transport following major floods with widespread landslides, the formation and failure of landslide dams and channel blockages caused by debris-flow deposits, and the supply of large wood due to shallow landslides in forested catchments. The methods for predicting landslides and debris flows at different spatial and temporal scales, with a focus on interactions with floods in the main river channels, are briefly described and reviewed. Finally, some research topics that could open valuable prospects for the advancement of research on these topics are mentioned.
High density distributed strain sensing of landslide in large scale physical model
L. Schenato ; M. Camporese ; S. Bersan ; S. Cola ; A. Galtarossa ; A. Pasuto ; P. Simonini ; P. Salandin ; L. Palmieri, 2017, High density distributed strain sensing of landslide in large scale physical model,
25th International Conference on Optical Fiber Sensors, Jeju, Korea, 24-28/04/2017,
Abstract
This paper describes the application of a commercial distributed optical fiber sensing system to a ...
This paper describes the application of a commercial distributed optical fiber sensing system to a large scale physical model of landslide. An optical fiber cable, deployed inside the landslide body, is interrogated by means of optical frequency domain reflectometry with very high spatial density. A shallow landslide is triggered in the physical model by artificial rainfall and the evolution of the strain is measured up to the slope failure. Precursory signs of failure are detected well before the collapse, providing insights to the failure dynamic.
Hydro-geomorphic connectivity and landslide features extraction to identifying potential threats and hazardous areas
Tarolli P., Fuller, I. C., Basso F., Cavalli M., Sofia G., 2017, Hydro-geomorphic connectivity and landslide features extraction to identifying potential threats and hazardous areas,
European Geosciences Union - General Assembly 2017, Vienna (Austria), 23/04/2017-28/04/2017,
Abstract
Hydro-geomorphic connectivity has significantly emerged as a new concept to understand the transfer of surface
water ...
Hydro-geomorphic connectivity has significantly emerged as a new concept to understand the transfer of surface
water and sediment through landscapes. A further scientific challenge is determining how the concept can be used
to enable sustainable land and water management. This research proposes an interesting approach to integrating
remote sensing techniques, connectivity theory, and geomorphometry based on high-resolution digital terrain
model (HR-DTMs) to automatically extract landslides crowns and gully erosion, to determine the different rate of
connectivity among the main extracted features and the river network, and thus determine a possible categorization
of hazardous areas.
The study takes place in two mountainous regions in the Wellington Region (New Zealand). The methodology is a
three step approach. Firstly, we performed an automatic detection of the likely landslides crowns through the use
of thresholds obtained by the statistical analysis of the variability of landform curvature. After that, the research
considered the Connectivity Index to analyse how a complex and rugged topography induces large variations in
erosion and sediment delivery in the two catchments. Lastly, the two methods have been integrated to create a
unique procedure able to classify the different rate of connectivity among the main features and the river network
and thus identifying potential threats and hazardous areas. The methodology is fast, and it can produce a detailed
and updated inventory map that could be a key tool for erosional and sediment delivery hazard mitigation. This
fast and simple method can be a useful tool to manage emergencies giving priorities to more failure-prone zones.
Furthermore, it could be considered to do a preliminary interpretations of geomorphological phenomena and more
in general, it could be the base to develop inventory maps.
References
Cavalli M, Trevisani S, Comiti F, Marchi L. 2013. Geomorphometric assessment of spatial sediment connectivity
in small Alpine catchments. Geomorphology 188_ 31-41 DOI_ 10.1016/j.geomorph.2012.05.007
Sofia G, Dalla Fontana G, Tarolli P. 2014. High-resolution topography and anthropogenic feature extraction_ testing
geomorphometric parameters in floodplains. Hydrological Processes 28 (4): 2046-2061 DOI_ 10.1002/hyp.9727
Tarolli P, Sofia G, Dalla Fontana G. 2012. Geomorphic features extraction from high-resolution topography_
landslide crowns and bank erosion. Natural Hazards 61 (1): 65-83 DOI_ 10.1007/s11069-010-9695-2
Structural and functional connectivity in the agricultural Can Revull catchment (Mallorca, Spain)
Calsamiglia A., Garcia-Comendador J., Fortesa J., Crema S., Cavalli M., Alorda B., Estrany J., 2017, Structural and functional connectivity in the agricultural Can Revull catchment (Mallorca, Spain),
European Geosciences Union - General Assembly 2017, Vienna (Austria), 23/04/2017-28/04/2017,
Abstract
Unravelling the spatio-temporal variability of the sediment transfer within a catchment represents a challenge of
great ...
Unravelling the spatio-temporal variability of the sediment transfer within a catchment represents a challenge of
great importance to quantify erosion, soil redistribution and their impacts on agricultural landscape. Structural and
functional connectivity have been identified as useful aspects of connectivity that may clarify how these processes
are coupled or decoupled in various types of catchment sediment cascades. In this study, hydrological and sediment
connectivity in a Mediterranean agricultural catchment (1.4 km2) modified through traditional drainage systems
(i.e. ditches and subsurface tile drainages) was assessed during two contrasted rainfall events occurred in October
2016 (20 mm in 24 h -return period < 1 yr-, I30 6.6 mm h-1 with 32 mm accumulated in 14 days) and in
December 2016 (99 mm in 24 h -return period 25 yr-, I30 23 mm h-1 with 39 mm accumulated in 14 days).
A morphometric index of connectivity (IC) was calculated to study the spatial patterns of structural connectivity.
The identification of the main sediment pathways -in terms of functional connectivity- was conducted by field
mapping, whilst the estimation of erosion and deposition rates by the analysis of high resolution digital terrain
models (i.e. 5 cm pix-1; RMSE < 0.05 m) obtained from automated digital photogrammetry and unmanned aerial
vehicle (UAV). The IC estimations allowed the identification of the most (dis-)connected areas related with the
anthropogenic control in the resisting forces of the catchment. On the one hand, in the upper part of the catchment,
depositional compartments were created by dry-stone walls that separate agricultural properties laminating
flash floods. On the other hand, in the lower part of the catchment these depositional compartments were generated
by an orthogonal network of ditches situated topographically above the natural thalwegs. In its turn, the
most connected areas are located in the steepest parts of the catchment under rainfed herbaceous crops without
dry stone walls and also within the lowland depositional compartments where the pathways are diverted generating
parallel concentrated flows because of the greater elevation of these ditches. The observed spatial patterns
of functional connectivity showed significant differences between the two events, although well fitted with IC as
a clear evidence of anthropogenic controls in the resisting forces. During the October 2016 event -representative
of high frequency-low magnitude events in the catchment- traditional drainage systems controlled the water and
sediment transfer which was mainly concentrated within the ditches. By contrast, during the event of December
2016 -representative of extreme events- this transfer process was controlled by the natural morphology of the
catchment, which activated coupling mechanisms between different compartments, increasing the effective area
and triggering erosion processes including the formation of rills and incipient gullies. The spatial location of the
sediment mobilization and deposition areas during the extreme event in December 2016 is well fitted with the IC
estimations. The application of IC, therefore, may provide useful information to improve the drainage systems
design and the implementation of measures to prevent soil losses.
Coupling climate conditions, sediment sources and sediment transport in an alpine basin
Rainato R., Picco L., Cavalli M., Mao L., Neverman A. J., Tarolli P., 2017, Coupling climate conditions, sediment sources and sediment transport in an alpine basin,
European Geosciences Union - General Assembly 2017, Vienna (Austria), 23/04/2017-28/04/2017,
Abstract
In a fluvial system, mountain basins control sediment export to the lowland rivers. Hence, the ...
In a fluvial system, mountain basins control sediment export to the lowland rivers. Hence, the analysis of the erosion
processes and sediment delivery patterns that act in mountain basins is important. Several studies have investigated
the alterations triggered by recent climatic change on the hydrological regime, whilst only a few works have
explored the consequences on the sediment dynamics. Here we combined and analyzed the quasi-unique dataset
of climatic conditions, landscape response, and sediment export produced, since 1986 in the Rio Cordon basin (5
km2, Eastern Italian Alps) to examine the sediment delivery processes occurring in the last three decades. The
temperature, precipitation, and fluvial sediment fluxes in the basin were analyzed using continuous measurement
executed by a permanent monitoring station, while the landscape evolution was investigated by three sediment
source inventories established in 1994, 2006, and 2016. Thus, the analysis focused on the trends exhibited during
the periods 1986-1993, 1994-2006, and 2007-2015. In terms of climatic conditions, three distinct climate forcing
stages can be observed in the periods analyzed_ a relatively stable phase (1986-1993), a period characterized by
temperature and rainfall fluctuations (1994-2006), and a more recent warmer and wetter phase (2007-2015). In
the 1986-1993 period, the fluvial sediment fluxes reflected the stable trend exhibited by the climatic conditions.
In the subsequent 1994-2006 period, the average temperature and precipitation were in line with that previously
observed, although with higher interannual variability. Notwithstanding the climate forcing and the occurrence of
high magnitude/low frequency floods that strongly influenced the source areas, between 1994 and 2006 the Rio
Cordon basin showed relatively limited erosion activity. Hence, the climatic conditions and the landscape response
can only partially explain the strong increase of sediment export recorded in the 1994-2006 period. In this sense, the
sediment availability resulting from armour layer and bedform removal appears crucial to describing the sediment
fluxes during this period, stressing the key role of the in-channel sediment supply. In the recent period 2007-2015 a
marked climate warming accompanied by increased precipitation was observed. This climate forcing did not affect
the landscape evolution, with sediment source extent remaining substantially in line between 2006 and 2016. The
absence of a significant landscape response and the restoration of the channel armour layer can describe the limited
sediment fluxes observed during the last decade. In particular, the increased temperature and precipitation were not
accompanied by an increase in flood occurrence and magnitude, stressing the evident absence of hillslope-channel
network coupling. This research was funded by the University of Padova Research Projects 'Sediment transfer
processes in an Alpine basin_ sediment cascades from hillslopes to the channel network-BIRD167919'.
Assessing historical sediment connectivity in a mesoscale catchment using multi-temporal aerial photographs
Llena M., Cavalli M., Vericat D., Smith M., 2017, Assessing historical sediment connectivity in a mesoscale catchment using multi-temporal aerial photographs,
European Geosciences Union - General Assembly 2017, Vienna (Austria), 23/04/2017-28/04/2017,
Abstract
Land uses changes interfere on sediment production and delivery in fluvial channel networks. The study ...
Land uses changes interfere on sediment production and delivery in fluvial channel networks. The study of
the evolution of sediment connectivity associated with different land use changes is prerequisite for a better
understanding of sediment budgets and associated processes. Previous studies examined historical changes of
sediment connectivity, but most are based on indices of sediment connectivity (IC) estimated by means of_ (i)
a single Digital Elevation Model (DEM), usually the most recent; and (ii) a weighting factor parameter, used
in IC as a proxy of the impedance to sediment fluxes, that is assessed based on land use properties. However,
some structural or geomorphological elements determined by both natural processes (e.g. rock falls) and human
impacts (e.g. land uses changes) may have fundamental influences on connectivity, especially in a mountain areas
typically affected by mass movements and strong land crop abandonment during the 20th century. Therefore, all
these elements are able to modify landscape properties and, consequently, sediment connectivity.
Within this context, the objective of this work is to develop and apply a workflow to extract historical IC
maps using different information that can be obtained from historical aerial photos. A prerequisite of the analysis
is to reconstruct the land use and the landscape properties at the period in which the IC is estimated. The analysis
consists of three interrelated steps_ extraction of historical ortophotomaps and point clouds from historical photos
(aerial photos from 1957 and 1977) in the Upper River Cinca (Southern Pyrenees), derivation of land use maps
and topographic models for those periods, and assessment and comparison of historical sediment connectivity
in contrasted sub-catchments exhibiting variable degrees of land use change. The study of changes on sediment
connectivity through time may provide valuable information to understand some of the floodplain and channel
adjustments that are observed in the majority of the fluvial systems experiencing massive land use changes in their
headwaters during the middle of the 20th century.
Assessing the effects of check dams on sediment dynamics in a debris-flow catchment through SfM technique
Cucchiaro S., Beinat A., Calsamiglia A., Cavalli M., Cazorzi F., Crema S., Marchi L., 2017, Assessing the effects of check dams on sediment dynamics in a debris-flow catchment through SfM technique,
European Geosciences Union - General Assembly 2017, Vienna (Austria), 23/04/2017-28/04/2017,
Abstract
The Moscardo Torrent (eastern Italian Alps) is a small rugged catchment (drainage area 4.1 km2, ...
The Moscardo Torrent (eastern Italian Alps) is a small rugged catchment (drainage area 4.1 km2, range in elevation
between 890 and 2043 m) frequently affected by debris flows that deliver large amounts of sediment to the receiving
stream, and cause concerns for infrastructures located on the alluvial fan and near the confluence.
Over the last decades, hydraulic control works were implemented in the main channel to limit bed erosion and to
stabilize channel banks. Although the objectives of training works have been only partly achieved, check dams and
hillslope stabilization works have affected the sediment transfer from hillslopes to the channels and along the main
channel.
The effects of hydraulic control works were investigated by means of multi-temporal Structure from Motion (SfM)
surveys based on images taken from the ground and UAV. The ground and air based surveys were carried out over
a channel reach in which two check dams have recently been built. SfM surveys were taken before and after three
debris-flow events (occurred between June and July 2016), allowing the generation of four high-resolution Digital
Elevation Models (DEMs).
Geomorphic changes caused by the debris-flow events have been assessed in order to produce the DEM of Differences
(DoDs with a 0.2 m spatial resolution) that allowed estimating erosion and deposition volumes in the study
area. Furthermore a debris-flow monitoring system has been in operation in the Moscardo Torrent; the analysis
of the videos and of the hydrographs recorded by ultrasonic sensors permitted to assess the debris-flow volumes.
These estimates were used to characterize the magnitude of events in support of the topographic analysis.
By examining the changing pattern of erosion and deposition over time it was possible to understand the check
dams' effects on sediment dynamics. The results show that the new check dams effectively stored sediment transported
by the three debris flows. However, once the check dams have been completely filled, they lost their functionality,
letting sediment flow downstream along paths drawn accidentally by the torrent control works and by the
morphology of debris-flow deposits. Moreover, debris-flow lobes deposited upstream of the check dams could act
as sediment sources further increasing downstream debris-flow magnitude.
Integrating remotely sensed hydrologic parameters into an index of sediment connectivity
Ahlmer A., Kalantari Z., Cavalli M., Crema S., 2017, Integrating remotely sensed hydrologic parameters into an index of sediment connectivity,
European Geosciences Union - General Assembly 2017, Vienna (Austria), 23/04/2017-28/04/2017,
Abstract
As a consequence of a changing climate the occurrence of unexpected events, like flooding and ...
As a consequence of a changing climate the occurrence of unexpected events, like flooding and erosion, that
affects urban areas will most likely increase. The infrastructure is especially vulnerable to heavy rainfall events
due to high costs and long term investments. Accumulation of water and sediments thus has a large impact on the
consequences of such events, and it is therefore essential to identify factors that influence the catchment and the
occurrence of flooding.
Both spatial and temporal characteristics of the patterns of sediment connectivity is important for estimating
the sediment contribution and transfer paths in a catchment. In recent years several approaches have been
developed to assess sediment connectivity, as for example the geomorphometric indices of sediment connectivity
which mainly picture a static frame of the system. With the development of remote sensing technology and the
growing availability of satellite images the opportunity to consider also temporal variability and hydrological
parameters as soil moisture within this kind of indices is increasing (e.g., Foerster et al., 2014; Gay et al., 2015).
However, there is still a knowledge gap in considering the potential of soil moisture satellite imagery in assessing
sediment connectivity at the catchment scale.
This study aims to integrate spatial and temporal soil moisture properties in the index of sediment connectivity
by Cavalli et al. (2013), which can be used to predict where flood events will have the strongest impact. The
results will provide decision makers with a prediction tool to identify road-intersections that are prone to flood risk
at the catchment scale. The method developed in this study would increase awareness and be a basis for decision
makers and stakeholders to promote action towards enabling sustainable water and land management.
References
Cavalli, M., Trevisani, S., Comiti, F., Marchi, L. , (2013) Geomorphometric assessment of spatial sediment
connectivity in small Alpine catchments. Geomorphology 188_ 31-41, doi_10.1016/j.geomorph.2012.05.007.
Foerster, S., Wilczok,.C., Brosinsky, A., Segl, K., (2014) Assessment of sediment connectivity from vegetation
cover and topography using remotely sensed data in a dryland catchment in the Spanish Pyrenees. J Soils
Sediments 14_1982-2000
Gay, A., Cerdan, O., Mardhel, V., Desmet, M. (2015) Application of an index of sediment connectivity in
a lowland area. J. Soils Sediments 16(1), 280-293, doi_10.1007/s11368-015-1235-y,.
Evaluation of anthropogenic effects on the sediment delivery dynamics in response to slope instability
Persichillo M.G.; Bordoni M.; Cavalli M.; Crema S.; Meisina C., 2017, Evaluation of anthropogenic effects on the sediment delivery dynamics in response to slope instability,
Rendiconti online Società Geologica Italiana 42 (2017): 5–9. doi_10.3301/ROL.2017.01,
Abstract
In this work a sediment connectivity assessment was performed in order to evaluate the role ...
In this work a sediment connectivity assessment was performed in order to evaluate the role of anthropogenic effects on the sediment delivery dynamic, in response to slope instability. In particular, the potential connection of sediment source areas with the main channel networks and roads was investigated. Two catchments with different size and morphological setting were analysed_ the Rio Frate and Versa catchments (Oltrepo Pavese, Northern Apennines, Italy). The two areas were affected by important anthropogenic effects, such as land use changes, drainage system and road network modifications. Moreover, several shallow landslides occurred in these areas in 2009 and 2013. The performed analysis allowed to obtain maps of sediment connectivity according to the main landscape modification due to human activities. In particular, the effects of these modifications on the degree of connectivity between shallow landslides, roads and streams, were investigated. In addition, the instability phenomena characterised by the highest connectivity were determined, allowing the determination of the areas where the mobilized sediment from shallow landslides can potentially reach roads and stream network, causing potentially extensive damages.
An updated sediment source areas inventory in the Rio Cordon catchment (Dolomites)
Ferrato C.; De Marco J.; Tarolli P.; Cavalli M., 2017, An updated sediment source areas inventory in the Rio Cordon catchment (Dolomites),
Rendiconti online Società Geologica Italiana 42 (2017): 10–13. doi_10.3301/ROL.2017.02,
Abstract
This study presents an inventory of sediment source areas updated to 2016 of the Rio ...
This study presents an inventory of sediment source areas updated to 2016 of the Rio Cordon catchment, a small headwater basin located in the Eastern Italian Alps. The aim of the 2016 inventory was to update an old sediment source areas dataset dating back to 2006, built using LiDAR-derived geomorphometric parameters interpretation and field survey, in order to evaluate the geomorphic changes occurred in the last 10 years in the catchment. The new inventory was realized by means of an extensive field survey campaign conducted with a mobile GIS mounted on a rugged notebook integrating a GPS receiver. Pictures of individual or collective sediment source areas were also acquired in order to integrate the GIS dataset and to better define their current status of activity. The images were also used for a comparison with the images acquired in 2006 to identify the evolution or stabilization of each sediment source area. The identification and delimitation of large and/or unreachable areas was carried out in the office by interpreting aerial photo images (Bing satellite images and Web Map Services for AGEA 2009-2012 aerial photographs, compared with the old LiDAR-derived high resolution images used for the 2006 sediment source inventory). The comparison with the previous inventory shows that several old sediment sources resulted totally stabilized indicating a general decrease of erosion processes in the catchment. In contrast, some new sediment source areas were identified. They were mainly related to a very recent rock fall that took place in July 2016 in the Lastoni di Formin group and many new shallow landslides were found in the upper part of small Rio Cordon tributary where a small debris flow event occurred in 2012.
Analysis of acoustic emission patterns for monitoring of rock slope deformation mechanisms
Codeglia, D., Dixon, N., Fowmes, G.J., Marcato, G.,, 2017, Analysis of acoustic emission patterns for monitoring of rock slope deformation mechanisms,
Engineering geology 219 (2017): 21–31. doi_10.1016/j.enggeo.2016.11.021,
DOI: 10.1016%2Fj.enggeo.2016.11.021
Abstract
Acoustic emission (AE) is generated in soil and rock materials by rearrangement of particles during ...
Acoustic emission (AE) is generated in soil and rock materials by rearrangement of particles during displacement or increasing damage in the microstructure preceding a collapse; therefore AE is appropriate for estimation of slope degradation. To overcome the high attenuation that characterise geological materials and thus to be able to monitor AE activity, a system that makes use of a waveguide to transmit AE waves from a deforming zone to a piezoelectric transducer was developed. The system quantifies acoustic activity as Ring Down Count (RDC) rates. In soil applications RDC rates have been correlated with the rate of deformation, whereas the recent application to rock slopes requires new interpretation strategies. In order to develop new strategies the system was installed at two rock slope trial sites in Italy and Austria. RDC rates from these sites, which have been measured over 5 and 1.5 years respectively, are analysed and clear and recurring trends are identified. The comparison of AE trends with response from a series of traditional instruments available at the sites allows correlation with changes in external slope loading and internal stress changes. AE signatures from the large rock slope in Italy have been identified as generated in response to variations in the groundwater level and snow loading. At the slope in Austria, AE signatures include the detachment of small boulders from the slope surface caused by the succession of freeze-thaw cycles during winter time. The work reported in this paper is contributing to the development of AE monitoring and interpretation strategies for rock slopes. The longer-term aim is to identify approaching failures and derive rules for setting thresholds that can be used to give warning of rock slope failures in time to enable action to be taken.
Flood probability quantification for road infrastructure_ Data-driven spatial-statistical approach and case study applications
Kalantari Z.; Cavalli M.; Cantone C.; Crema S.; Destouni G., 2017, Flood probability quantification for road infrastructure_ Data-driven spatial-statistical approach and case study applications,
Science of the total environment 581-582 (2017): 386–398. doi_10.1016/j.scitotenv.2016.12.147,
DOI: 10.1016%2Fj.scitotenv.2016.12.147
Abstract
Climate-driven increase in the frequency of extreme hydrological events is expected to impose greater strain ...
Climate-driven increase in the frequency of extreme hydrological events is expected to impose greater strain on the built environment and major transport infrastructure, such as roads and railways. This study develops a data-driven spatial-statistical approach to quantifying and mapping the probability of flooding at critical road-stream intersection locations, where water flow and sediment transport may accumulate and cause serious road damage. The approach is based on novel integration of key watershed and road characteristics, including also measures of sediment connectivity. The approach is concretely applied to and quantified for two specific study case examples in southwest Sweden, with documented road flooding effects of recorded extreme rainfall. The novel contributions of this study in combining a sediment connectivity account with that of soil type, land use, spatial precipitation-runoff variability and road drainage in catchments, and in extending the connectivity measure use for different types of catchments, improve the accuracy of model results for road flood probability.
Response time and water origin in a steep nested catchment in the Italian Dolomites
Penna D.; Zuecco G.; Crema S.; Trevisani S.; Cavalli M.; Pianezzola L.; Marchi L.; Borga M., 2017, Response time and water origin in a steep nested catchment in the Italian Dolomites,
Hydrological processes (Print) 31 (2017): 768–782. doi_10.1002/hyp.11050,
DOI: 10.1002%2Fhyp.11050
Abstract
In this study, we investigate the surface flow time of rise in response to rainfall ...
In this study, we investigate the surface flow time of rise in response to rainfall and snowmelt events at different spatial scales and the main sources originating channel runoff and spring water in a steep nested headwater catchment (Rio Vauz, Italian Dolomites), characterized by a marked elevation gradient. We monitored precipitation at different elevations and measured water stage/streamflow at the outlet of two rocky subcatchments of the same size, representative of the upper part of the catchment dominated by outcropping bedrock, at the outlet of a soil-mantled and vegetated subcatchment of similar size but different morphology, and at the outlet of the main catchment. Hydrometric data are coupled with stable isotopes and electrical conductivity sampled from different water sources during five years, and used as tracers in end-member mixing analysis, application of two component mixing models and analysis of the slope of the dual-isotope regression line. Results reveal that times of rise are slightly shorter for the two rocky subcatchments, particularly for snowmelt and mixed rainfall/snowmelt events, compared to the soil-mantled catchment and the entire Rio Vauz Catchment. The highly-variable tracer signature of the different water sources reflects the geomorphological and geological complexity of the study area. The principal end-members for channel runoff and spring water are identified in rainfall and snowmelt, which are the dominant water sources in the rocky upper part of the study catchment, and soil water and shallow groundwater, which play a relevant role in originating baseflow and spring water in the soil-mantled and vegetated lower part of the catchment. Particularly, snowmelt contributes up to 64 ± 8% to spring water in the concave upper parts of the catchment and up to 62 ± 11% to channel runoff in the lower part of the catchment. These results offer new experimental evidences on how Dolomitic catchments capture and store rain water and meltwater, releasing it through a complex network of surface and subsurface flow pathways, and allow for the construction of a preliminary conceptual model on water transmission in snowmelt-dominated catchments featuring marked elevation gradients.
Multi-scale debris flow vulnerability assessment and direct loss estimation of buildings in the Eastern Italian Alps
Ciurean R.L.; Hussin H.; van Westen C.J.; Jaboyedoff M.; Nicolet P.; Chen L.; Frigerio S.; Glade T., 2017, Multi-scale debris flow vulnerability assessment and direct loss estimation of buildings in the Eastern Italian Alps,
Natural hazards (Dordr.) (2017): 1–29. doi_10.1007/s11069-016-2612-6,
DOI: 10.1007%2Fs11069-016-2612-6
Abstract
Vulnerability assessment, as a component of the consequence analysis, represents a fundamental stage in the ...
Vulnerability assessment, as a component of the consequence analysis, represents a fundamental stage in the risk assessment process because it relates the hazard intensity to the characteristics of the built environment that make it susceptible to damage and loss. The objective of this work is to develop a quantitative methodology for vulnerability and loss assessment of buildings exposed to debris flows and apply it to a study area in NE Italy at local and regional scale. Using existing conceptual models of vulnerability and loss, this paper seeks to identify solutions for maximizing the information gained from limited observational damage data and a heterogeneous building data set. Two vulnerability models are proposed_ Model 1 is based on the generation of empirical vulnerability curves using observed intensities; Model 2 takes into account multiple resistance characteristics of buildings and uses modeled debris flow intensities. The process intensity descriptor in both cases is debris flow height. The vulnerability values obtained with the local (Model 1) and regional (Model 2) models are further multiplied with the building value to calculate the minimum and maximum loss for each building in the study area. Loss is also expressed as cumulative probability calculated with Model 1 using a Monte Carlo sampling technique. The methodology is applied in the Fella River valley (northeastern Italian Alps), a region prone to multiple mountain hazards. Uncertainties are expressed as minimum and maximum values of vulnerability, market values and loss. The results are compared with relevant published vulnerability curves and historical damage reports.
Application of a high resolution distributed temperature sensor in a physical model reproducing subsurface water flow
Bersan S., Schenato L., Rajendran A., Palmieri L., Cola S., Pasuto A., Simonini P., 2017, Application of a high resolution distributed temperature sensor in a physical model reproducing subsurface water flow,
Measurement (Lond., Print) 98 (2017): 321–324. doi_10.1016/j.measurement.2015.09.018,
DOI: 10.1016%2Fj.measurement.2015.09.018
Abstract
A distributed temperature optical fiber sensor system with a sub-centimeter spatial resolution has been incorporated ...
A distributed temperature optical fiber sensor system with a sub-centimeter spatial resolution has been incorporated in a sand-box model at the aim of investigating the variations induced by internal erosion on the temperature distribution in a dike. In particular, the laboratory investigation aims at studying the spatial distribution of the temperature variations occurring in the surroundings of an erosion channel (pipe). The calibration of the setup consisted in measuring the thermal response of an intact sample to a horizontal flow, with the inflowing water maintained at a constant temperature higher than the room temperature. No erosion occurred in the calibration test. The results of the calibration are presented in this paper and show that with the sensing system adopted temperature mapping in a soil sample can be obtained with such a richness of detail which is not comparable with that achieved adopting a system of pointwise sensors.
Assessment of erosion and deposition in steep mountain basins by differencing sequential digital terrain models
Cavalli, Marco; Goldin, Beatrice; Comiti, Francesco; Brardinoni, Francesco; Marchi, Lorenzo, 2017, Assessment of erosion and deposition in steep mountain basins by differencing sequential digital terrain models,
Geomorphology (Amst.) 291 (2017): 4–16. doi_10.1016/j.geomorph.2016.04.009,
DOI: 10.1016%2Fj.geomorph.2016.04.009
Abstract
Digital elevation models (DEMs) built from repeated topographic surveys permit producing DEM of Difference (DoD) ...
Digital elevation models (DEMs) built from repeated topographic surveys permit producing DEM of Difference (DoD) that enables assessment of elevation variations and estimation of volumetric changes through time. In the framework of sediment transport studies, DEM differencing enables quantitative and spatially-distributed representation of erosion and deposition within the analyzed time window, at both the channel reach and the catchment scale. In this study, two high-resolution Digital Terrain Models (DTMs) derived from airborne LiDAR data (2. m resolution) acquired in 2005 and 2011 were used to characterize the topographic variations caused by sediment erosion, transport and deposition in two adjacent mountain basins (Gadria and Strimm, Vinschgau - Venosta valley, Eastern Alps, Italy). These catchments were chosen for their contrasting morphology and because they feature different types and intensity of sediment transfer processes. A method based on fuzzy logic, which takes into account spatially variable DTMs uncertainty, was used to derive the DoD of the study area. Volumes of erosion and deposition calculated from the DoD were then compared with post-event field surveys to test the consistency of two independent estimates. Results show an overall agreement between the estimates, with differences due to the intrinsic approximations of the two approaches. The consistency of DoD with post-event estimates encourages the integration of these two methods, whose combined application may permit to overcome the intrinsic limitations of the two estimations. The comparison between 2005 and 2011 DTMs allowed to investigate the relationships between topographic changes and geomorphometric parameters expressing the role of topography on sediment erosion and deposition (i.e., slope and contributing area) and describing the morphology influenced by debris flows and fluvial processes (i.e., curvature). Erosion and deposition relations in the slope-area space display substantial differences between the Gadria and the Strimm basins. While in the former erosion and deposition clusters are reasonably well discriminated, in the latter, characterized by a complex stepped structure, we observe substantial overlapping. Erosion mostly occurred in areas that show persistency of concavity or transformation from convex and flat to concave surfaces, whereas deposition prevailingly took place on convex morphologies. Less expected correspondences between curvature and topographic changes can be explained by the variable sediment transport processes, which are often characterized by alternation of erosion and deposition between different events and even during the same event.
Rapporto tecnico sull’attività di caratterizzazione sperimentale di un interrogatore per sensori in fibra ottica con Avago Technologies Fiber GMBH (prot. 763 del 21
Schenato, L., 2016, Rapporto tecnico sull’attività di caratterizzazione sperimentale di un interrogatore per sensori in fibra ottica con Avago Technologies Fiber GMBH (prot. 763 del 21,
2016,
Abstract
In questo rapporto vengono presentati i risultati finali della caratterizzazione sperimentale di un interrogatore ...
In questo rapporto vengono presentati i risultati finali della caratterizzazione sperimentale di un interrogatore per sensori in fibra ottica sviluppato con Avago Technologies Fiber GMBH (sottoposto ad accordo di non divulgazione)
Deliverable D1.1 – Definition of specifications for DVS system
M. Gonzalez-Herraez, L. Palmieri, L. Schenato, 2016, Deliverable D1.1 – Definition of specifications for DVS system,
D1.1, 2016,
Abstract
Questo documento definisce le specifiche del sistema DVS (Distributed Vibration Sensor) da sviluppare nell'ambito del ...
Questo documento definisce le specifiche del sistema DVS (Distributed Vibration Sensor) da sviluppare nell'ambito del progetto DOMINO - WaterWorks2014 Cofunded Call
IL PROGETTO MAPPERS_ ESPERIENZA DI SMARTPHONESE CROWDSOURCINGPER LA GESTIONE DEI RISCHI
SIMONE FRIGERIO, 2016, IL PROGETTO MAPPERS_ ESPERIENZA DI SMARTPHONESE CROWDSOURCINGPER LA GESTIONE DEI RISCHI,
La Collaborazione fra ICT e Geoscienze, Fondazione Politecnico di Milano, 4 Febbraio 2016,
Abstract
SCIENTIFIC AIMS
?Framework building within risk management (gaps within preparedness step andemergency support)
?Real-time goal of crowdsourcing ...
SCIENTIFIC AIMS
?Framework building within risk management (gaps within preparedness step andemergency support)
?Real-time goal of crowdsourcing with citizens/volunteers
?Geo-localised standard information (pre-compiled and updated by data response)
?Long-term goal of raising participation
?Continuous feedback from users to the rescue service
?Enhancing people's awareness and contribution of the territory
Progetto MAppERS_ Smartphone e Web 2.0 per il crowdsourcing nei rischi naturali
SIMONE FRIGERIO, LUCA SCHENATO, GIULIA BOSSI, MATTEO MANTOVANI, GIANLUCA MARCATO, ALESSANDRO PASUTO, 2016, Progetto MAppERS_ Smartphone e Web 2.0 per il crowdsourcing nei rischi naturali,
XII Convegno Nazionale del Gruppo di Geoscience e Tecnologie Informatiche Sezione della Società Geologica Italiana, Gavorrano (GR), 12 - 14 Giugno 2017,
Abstract
Helsinki requires a complex multi-risk management and context-specific real cases. Lack of resources management and ...
Helsinki requires a complex multi-risk management and context-specific real cases. Lack of resources management and volunteers roles especially with scarce local-based prioritization. A high number of volunteers within squads obliges real time tracking
Utilizzo dei modelli digitali ad alta risoluzione per la caratterizzazione morfologica di reticolo e bacino idrografico
Cavalli M., 2016, Utilizzo dei modelli digitali ad alta risoluzione per la caratterizzazione morfologica di reticolo e bacino idrografico,
Workshop IAEG-OGER "L'uso dei dati telerilevati in geologia applicate_ esperienze e prospettive", Bologna, 25/11/2016,
Abstract
Intervento su invito al Workshop IAEG-OGER "L'uso dei dati telerilevati in geologia applicate_ esperienze e ...
Intervento su invito al Workshop IAEG-OGER "L'uso dei dati telerilevati in geologia applicate_ esperienze e prospettive"
Towards the integration of structural and functional approaches for the characterization of sediment dynamics in mountain catchments
Cavalli M., Crema S., Marchi L., 2016, Towards the integration of structural and functional approaches for the characterization of sediment dynamics in mountain catchments,
11 Convegno GIT - Geology and Information Technology, Torino, 13-15/06/2016,
Abstract
In this work the integration between structural, essentially based on the system structure (i.e., topography), ...
In this work the integration between structural, essentially based on the system structure (i.e., topography), and functional (i.e. considering processes driving sediment and energy fluxes) approaches is proposed for characterizing sediment connectivity in a small mountain catchment. The structural approach, based on a topography-based sediment connectivity index, is used for assessing hillslope-to-channel connectivity. Since field data on processes driving sediment transport along the channel network are available, a functional approach has been devised to estimate within-channel connectivity. An index of unit stream power computed from the hydraulic properties of the channel (i.e., discharge, slope and channel width) has been compared with the critical unit stream power computed from incipient motion thresholds derived from field data to identify the cells of the Digital Terrain Model (DTM) in which sediment can be mobilized under near-bankfull conditions. The index expressing the within-channel connectivity is given by the length of the reaches consisting of contiguous cells that exceed the critical unit stream power. During high-magnitude floods, when unit stream power values exceed the threshold for incipient motion, channels experience an increase in both hydrological and sediment connectivity. The proposed index characterizes those sections of the channel network that are effectively connected under near-bankfull conditions. The model has been developed and tested in a small mountain catchment in the Italian Alps (Strimm catchment, 8.42 km2) in which a high-resolution DTM and monitored discharge and sediment transport data are available. The integration between structural and functional indices of sediment connectivity has permitted characterizing the spatial pattern of sediment connectivity on the hillslope and pointing out potential sites for sediment erosion, entrainment and deposition along the main channel network. This combined approach represents a new development of the index of connectivity considering sediment transport process along the channel network, with the only limitation related to field data availability. However, further testing is required to validate the index in order apply it to other catchments.
Le valutazioni geomorfologiche sono necessarie per la valutazione del rischio alluvionale
Comiti F., Borga M., Bussettini M., Marchi L., Rinaldi M., Surian N., 2016, Le valutazioni geomorfologiche sono necessarie per la valutazione del rischio alluvionale,
XXXV Convegno Nazionale di Idraulica e Costruzioni Idrauliche, pp. 525–528, Bologna, 14-16 Settembre 2016,
Abstract
· I fenomeni di piena eccezionale in Italia sono quasi sempre accompagnati da notevole trasporto ...
· I fenomeni di piena eccezionale in Italia sono quasi sempre accompagnati da notevole trasporto di sedimento grossolano e di materiale legnoso, che modificano la geometria degli alvei e creano occlusioni.
· Una pianificazione territoriale basata unicamente sui risultati di modellazioni idrauliche è nella maggior parte dei casi non adeguata ai fenomeni che realmente accadono durante eventi estremi.
· Le valutazioni geomorfologiche permettono la definizione di scenari di evento più aderenti alla realtà e che possono essere analizzati successivamente tramite modelli numerici.
Inter-disciplinary post-event surveys to untangle hazard and vulnerability in the impacts of flash-flood events in the Mediterranean
Delrieu G.,
Ruin I.,
Gaume E.,
Borga M.,
Anquetin S.,
Boudevillain B.,
Creutin J-D.,
Lutoff C.,
Marchi L.,
Payrastre O.,
Scolobig A., 2016, Inter-disciplinary post-event surveys to untangle hazard and vulnerability in the impacts of flash-flood events in the Mediterranean,
The Mediterranean Region under Climate Change. A Scientific Update, 2016,
Abstract
Heavy precipitation events (HPE) and flash floods (FF) are common phenomena over the Mediterranean region. ...
Heavy precipitation events (HPE) and flash floods (FF) are common phenomena over the Mediterranean region.
The contribution provides illustrative results obtained from inter-disciplinary post-event surveys (PES) aimed at understanding the complexity of both the hydrological responses to HPE and the behavior of the exposed populations during such sudden crises.
Joints representation strategy_ performance evaluation by a Finite Element code. A feasibility analysis of a tunnel infrastructure in the Carnian Alps
Tedesco, Giacomo; Borgatti, Lisa; Bondua, Stefano; Marcato, Gianluca, 2016, Joints representation strategy_ performance evaluation by a Finite Element code. A feasibility analysis of a tunnel infrastructure in the Carnian Alps,
Rendiconti online Società Geologica Italiana 41 (2016): 332–335. doi_10.3301/ROL.2016.161,
Abstract
This study is part of a wider feasibility analysis of a new forestry road in ...
This study is part of a wider feasibility analysis of a new forestry road in the Dolomitic region. The investigated area is located in northeastern Italy, in the Carnic Alps complex geological context. The rock mass which would be crossed by the tunnel is a highly tectonized limestone characterized by a relatively high strength of the intact rock. The project focuses on the rock mass characterization and the modelling of its behavior by means of numerical simulations with a Finite Elements (FE) code. The generalized Hoek-Brown criterion is used, normal and shear stiffness of the joints are evaluated and different strategies for the representation of the rock mass discontinuities are adopted. The effects of two support systems, preliminary designed by a diffused simplified method, are evaluated focusing on the space around the tunnel, where the joints reach the critical state.
Sediment sources and sediment connectivity monitoring in mountainous catchments
Marchi L., 2016, Sediment sources and sediment connectivity monitoring in mountainous catchments,
CONNECTEUR - COST Action ES1306 - Field Meeting Israel, Haifa - Masada - Beer Sheva, 4-8 december 2016,
Abstract
The presentation considers two approaches to sediment connectivity monitoring_
1) opportunistic survey of sediment sources on ...
The presentation considers two approaches to sediment connectivity monitoring_
1) opportunistic survey of sediment sources on hillslopes (essentially event landslides) after major floods by means of remote and proximal sensing and analysis of coupling/decoupling with the channel network.
2) measurements in instrumented catchments (field surveys and DoD from TLS and LiDAR), including linking the evaluation of sediment supply from hillslopes to the monitoring of sediment fluxes at monitoring stations.
Semi-auxetic Optical Fibre Distributed Load Sensor
Luca Schenato, Alessandro Pasuto, Andrea Galtarossa, and Luca Palmieri, 2016, Semi-auxetic Optical Fibre Distributed Load Sensor,
Asia-Pacific Optical Sensors Conference, pp. 1–3, Shanghai China, 11-14 October 2016,
Abstract
A distributed optical fibre load sensor exploiting a semi-auxetic structure is presented. The fibre is ...
A distributed optical fibre load sensor exploiting a semi-auxetic structure is presented. The fibre is interrogated by means of optical frequency domain reflectometry. The device is described and a prototype is assembled and characterized.
Hydrometeorological Characterization of a Flash Flood Associated with Major Geomorphic Effects_ Assessment of Peak Discharge Uncertainties and Analysis of the Runoff Response
AMPONSAH, W., MARCHI, L., ZOCCATELLI, D., BONI, G., CAVALLI, M., COMITI, F., CREMA, F., LUCÍA, A., MARRA, F., BORGA, M., 2016, Hydrometeorological Characterization of a Flash Flood Associated with Major Geomorphic Effects_ Assessment of Peak Discharge Uncertainties and Analysis of the Runoff Response,
Journal of hydrometeorology (Online) 17 (2016): 3063–3077. doi_10.1175/JHM-D-16-0081.1,
DOI: 10.1175%2FJHM-D-16-0081.1
Abstract
Postflood indirect peak flow estimates provide key information to advance understanding of flash flood
hydrometeorological processes, ...
Postflood indirect peak flow estimates provide key information to advance understanding of flash flood
hydrometeorological processes, particularly when peak observations are combined with flood simulations
from a hydrological model. However, indirect peak flow estimates are affected by significant uncertainties,
which are magnified when floods are associated with important geomorphic processes. The main objective
of this work is to advance the integrated use of indirect peak flood estimates and hydrological model
simulations by developing and testing a procedure for the assessment of the geomorphic impacts-related
uncertainties. The methodology is applied to the analysis of an extreme flash flood that occurred on the
Magra River system in Italy on 25 October 2011. The event produced major geomorphic effects and peak
discharges close to the maxima observed for high-magnitude rainstorm events in Europe at basin scales
ranging from 30 to 1000 km2. Results show that the intensity of geomorphic impacts has a significant effect
on the accuracy of postflood peak discharge estimation andmodel-based flood response analysis. It is shown
that the comparison between rainfall-runoff model simulations and indirect peak flow estimates, accounting
for uncertainties, may be used to identify erroneous field-derived estimates and isolate consistent
hydrological simulations. Comparison with peak discharges obtained for other Mediterranean flash floods
allows the scale-dependent flood response of the Magra River system to be placed within a broader hydroclimatological
context. Model analyses of the hydrologic response illustrate the role of storm structure
and evolution for scale-dependent flood response.
Uso di dati LiDAR aereo e terrestre per la modellazione della dinamica del sedimento
Cucchiaro, S., Cavalli, M., De Luca, A., Marchi, L., Cazorzi, F., 2016, Uso di dati LiDAR aereo e terrestre per la modellazione della dinamica del sedimento,
Scritti in onore di Salvatore Puglisi, edited by V. Ferro, F. Gentile, G. Trisorio Liuzzi, pp. 275–282, 2016,
Abstract
L'integrazione di dati topografici ad alta risoluzione, derivanti da diverse tecnologie
quali LiDAR sia aereo (ALS) ...
L'integrazione di dati topografici ad alta risoluzione, derivanti da diverse tecnologie
quali LiDAR sia aereo (ALS) sia terrestre (TLS) e strumentazione GPS, ha permesso
di generare, mediante una procedura di "data fusion", una serie di Modelli
Digitali del Terreno (DTM) multitemporali con 1 m di risoluzione. I DTM realizzati
sono stati utilizzati per stimare gli effetti della costruzione di una nuova briglia sulla
dinamica del sedimento in un piccolo bacino interessato da colate detritiche. Il calcolo
di un indice di connettività del sedimento, prima e dopo i lavori di sistemazione
idraulico-forestale, ha consentito di valutare l'efficacia degli interventi eseguiti e la
potenziale variazione del flusso di materiale trasportato.
Analisi idrologica della piena improvvisa del 2 agosto 2014 in un piccolo bacino delle Prealpi Venete
Destro E., Marchi L., Amponsah W., Tarolli P., Crema S., Zoccatelli D., Marra F., Borga M., 2016, Analisi idrologica della piena improvvisa del 2 agosto 2014 in un piccolo bacino delle Prealpi Venete,
Scritti in onore di Salvatore Puglisi, edited by V. Ferro, F. Gentile, G. Trisorio Liuzzi, pp. 307–316. Cosenza_ Edibios, 2016,
Abstract
Il lavoro illustra l'analisi idrologica della piena improvvisa verificatasi il 2 agosto
2014 nelle Prealpi Venete. ...
Il lavoro illustra l'analisi idrologica della piena improvvisa verificatasi il 2 agosto
2014 nelle Prealpi Venete. La disponibilità di stime di precipitazione ad alta risoluzione
spazio-temporale, ottenute da osservazioni radar e da pluviografi, unitamente
a valutazioni della risposta idrologica derivanti da rilievi post-evento, hanno offerto
l'opportunità di studiare i meccanismi idrologici associati a questo evento di piena di
carattere estremo. L'evento meteorico è caratterizzato da una durata di circa 100
minuti, con intensità puntuali di pioggia che eccedono 150 mm su un'ora. L'analisi
idrologica, condotta su sette bacini interessati dall'evento, mostra come i picchi di
portata unitaria al colmo siano particolarmente severi, con valori pari a 20 m3 s-1km-2
per bacini di 5-10 km2.
Hydrogeological monitoring and modelling in the S. Lorenzo road tunnel area (Passo della Morte, Udine) for the design of countermeasure works
Petronici, Francesca; Borgatti, Lisa; Cervi, Federico; Piccinini, Leonardo; Bonaga, Gilberto; Marcato, Gianluca, 2016, Hydrogeological monitoring and modelling in the S. Lorenzo road tunnel area (Passo della Morte, Udine) for the design of countermeasure works,
Rendiconti online Società Geologica Italiana 39 (2016): 93–96. doi_10.3301/ROL.2016.55,
Abstract
In the eastern Italian Alps, a large deep-seated rock block slide affects the S. Lorenzo ...
In the eastern Italian Alps, a large deep-seated rock block slide affects the S. Lorenzo road tunnel (46°23'49" N, 12°42'51" E) along the National Road 52 "Carnica", near to Passo della Morte (Udine Province); the tunnel was excavated through a fractured carbonatic rock mass overthrusted on clay-rich units. Previous studies of the unstable slope outlined the relationship between slope displacements and groundwater flow in the fractured rock mass. The conceptual geological model of the area, together with field observations, allowed specific investigation and monitoring activities to be defined in order to investigate this relationship. In particular, during the last years, six weirs were built and pressure transducers were installed in order to assess the total water discharge from the area. Moreover, 14 piezometers were drilled outside and inside the tunnel to monitor the hydraulic head. After 15 years of monitoring the groundwater system can be described in detail. In particular, results show a double flow system. The first is almost constant for all the year, while the second is influenced by rainfall events and is hosted in faults, fractures and joints in the western part of the tunnel, in the area of the larger and deep-seated rock slide. A three-dimensional groundwater flow model was built and calibrated along the total outflow from the road tunnel in order to better understand the interactions between groundwater flow and road infrastructure. In particular, the effects of countermeasures works, like the extension of the drainage adit in the carbonatic rock mass, was tested.
Evolutionary behaviour of the Tessina landslide
Cola, Simonetta; Gabrieli, Fabio; Marcato, Gianluca; Pasuto, Alessandro; Simonini, Paolo, 2016, Evolutionary behaviour of the Tessina landslide,
Rivista Italiana di Geotecnica 50 (2016): 51–70.,
Abstract
The Tessina Landslide, a complex movement which has been active for over the past 50 ...
The Tessina Landslide, a complex movement which has been active for over the past 50 years in the Alpago area of Belluno (Italy), was triggered in October 1960. As it is typical of Tertiary Flysch formations, its evolution has been characterized by periodical medium-large roto-translational slides in the source area evolving into earthflows, often jeopardizing the safety of the lower valley. Both the landslide and earth flows have been extensively monitored and studied over the past few decades. The main aim is a better understanding of their evolution mechanisms and the selection of appropriate mitigation strategies to reduce risk to the valley below. This paper presents data recorded by two real-time monitoring systems that have recently been installed in the area. The first system measures groundwater pressure and the displacements in a lateral section of the landslide that plays a crucial role in the stability of the entire area. The second, a new photogrammetric-based system which daily photographs the upper basin affected by the roto-translational movements, will permit us to evaluate the mechanisms triggering the earth flows. The data collected until now at the site have made it possible to better understand the stability of the various sections as well as the processes involved in earth flow formation. This information will make it possible to evaluate the effectiveness of future mitigation measures. Finally, a new black-box model that will predict the mobility of the lateral section of the landslide has been developed, and its performance has been compared to that of a viscous model commonly used to analyse slow-moving landslides.
An interactive web-GIS based risk analysis tool_ a case study in the Fella River Basin, Italy
Aye Z.C., Jaboyedoff M., Derron M.H., van Westen C.J., Hussin H.Y., Ciurean R.L., Frigerio S., Pasuto A., 2016, An interactive web-GIS based risk analysis tool_ a case study in the Fella River Basin, Italy,
Natural hazards and earth system sciences (Online) 16 (2016): 85–101. doi_10.5194/nhess-16-85-2016,
DOI: 10.5194%2Fnhess-16-85-2016
Abstract
This paper presents a prototype of an interactive web-GIS tool for risk analysis of natural ...
This paper presents a prototype of an interactive web-GIS tool for risk analysis of natural hazards, in particular for floods and landslides, based on open-source geospatial software and technologies. The aim of the presented tool is to assist the experts (risk managers) in analysing the impacts and consequences of a certain hazard event in a considered region, providing an essential input to the decision-making process in the selection of risk management strategies by responsible authorities and decision makers. This tool is based on the Boundless (OpenGeo Suite) framework and its clientside
environment for prototype development, and it is one of the main modules of a web-based collaborative decision support platform in risk management. Within this platform, the users can import necessary maps and information to analyze areas at risk. Based on provided information and parameters,
loss scenarios (amount of damages and number of fatalities) of a hazard event are generated on the fly and visualized interactively within the web-GIS interface of the platform. The annualized risk is calculated based on the combination of resultant loss scenarios with different return periods of the
hazard event. The application of this developed prototype is demonstrated using a regional data set from one of the case study sites, Fella River of northeastern Italy, of the Marie Curie ITN CHANGES project.
Testing the potential of Sentinel-1 TOPS interferometry for the detection and monitoring of landslides at local scale
SIMONE FIASCHI, MATTEO MANTOVANI, SIMONE FRIGERIO, GIANLUCA MARCATO, ALESSANDRO PASUTO, MARIO FLORIS, 2016, Testing the potential of Sentinel-1 TOPS interferometry for the detection and monitoring of landslides at local scale,
European Geosciences Union - General Assembly 2016, Vienna, 17-22 April 2016,
Abstract
The recent Sentinel-1 mission, started by ESA in April 2014, provides to the scientific community ...
The recent Sentinel-1 mission, started by ESA in April 2014, provides to the scientific community new capabilities for the continuous monitoring of the Earth. In particular, the Terrain Observation by Progressive Scans (TOPS) imaging technique used in the Interferometric Wide swath (IW) acquisition mode, allow us to acquire data over very wide areas (250 km swath) at 20m spatial resolution, with 12 days revisit time, making it suitable for ground displacement monitoring applications. With more than one year of SAR images available, it is now possible to carry out monitoring activities of slow moving phenomena such as landslides at both regional and local scales. In this work, we test the potential of Sentinel-1 InSAR for the monitoring of shallow landslides occurring in a densely vegetated area in the North-Eastern Italian Pre-Alps. The test area of about 25km2, is located in the Province of Vicenza (Veneto Region, NE Italy) and is characterized by elevations up to 700m a.s.l., low slope angles, and the outcropping of volcanic deposits (lavas, pyroclastites and ignimbrites) overlaid by eluvial and colluvial deposits. The entire area is affected by a large number of different instabilities, such as shallow soil slips, flows and rotational/translational slides that mainly occur after heavy rain. The landslides are damaging the buildings and the infrastructure, in particular the road network, causing high economic loss for the Municipality. The landslides monitoring activity is performed exploiting the available Sentinel-1 SAR images using both Small Baseline Subset (SBAS) and Persistent Scatterer (PS) techniques. Furthermore, we use the same techniques to process another SAR dataset made of 22 COSMO-SkyMed (CSK) X-band images acquired over the study area in the period March 2011 - September 2012. A first comparison of the results is performed in order to assess the landslides detection capabilities of the Sentinel-1 C-band in respect to the CSK X-band. Finally, the Sentinel- 1 results are cross-validated with the ERS-1/2 and ENVISAT PSI database available from "Portale Geografico Nazionale" allowing us to assess the quality of the obtained results in terms of data density and accuracy. The presented work shows the potential of the new Sentinel-1 TOPS mode interferometry in the monitoring of local scale ground instabilities in low urbanized territories pointing out what strengths and weaknesses emerged during the study activity.
Use of volunteers’ information to support proactive inspection of hydraulic structures
Juliette Cortes Arevalo (1,4), Simone Sterlacchini (2), Thom Bogaard (1), Simone Frigerio (3), Sandra Junier (1),
Luca Schenato (3), and Nick van den Giesen (1), 2016, Use of volunteers’ information to support proactive inspection of hydraulic structures,
European Geosciences Union - general assembly 2016, Vienna, 17-22 April 2016,
Abstract
Proactive management is particularly important to deal with the increasing occurrence of hydro-meteorological hazards in ...
Proactive management is particularly important to deal with the increasing occurrence of hydro-meteorological hazards in mountain areas were threats are often caused by multiple and sudden onset hazards such as debris flows. Citizen volunteers can be involved in supporting technicians on inspecting the structures' functional status. Such collaborative effort between managing organizations and local volunteers becomes more important under limited resources. To consider volunteers' information in support of proactive inspection of hydraulic structures, we developed a methodology applicable in day-to-day risk management. At first, in collaboration with technicians-in-charge, a data collection approach was developed for first level or pre-screening visual inspections that can be performed by volunteers. Methods comprise of a data collection exercise, an inspection forms and a learning session based on existent procedures in the FVG region and neighbouring regions. To systematically evaluate the individual inspection reports, we designed a support method by means of a multi-criteria method with fuzzy terms. The method allows the technicians-in-charge to categorize the reports in one of three levels, each corresponding with a course of action. To facilitate the evaluation of inspection reports, we transformed the decision support method into a prototype Web-GIS application. The design process of the Web-GIS framework followed a user-centred approach. The conceptual design incorporates four modules for managing the inspection reports_ 1) Registered users, 2) Inspection planning; 3) Available reports and 4) Evaluation of reports. The development of the prototype focused on the evaluation module and was implemented based on standard and interoperable open source tools. Finally, we organized a workshop with technicians in the study area to test the decision support method and get insights about the usefulness of the Web-GIS framework. Participants that took part of the workshop included technicians that were not involved in previous research activities. The involvement of new technicians was important due to their fresh perspectives. We looked at the effect of the quality of the input reports on the output of the decision support method. In addition, we compared the differences in the participants' advice during the inspection and the output from the decision support method. Participants' feedback led to a set of suggested improvements in the decision support method and the web-GIS application. We hope that the knowledge, theory and concept behind this decision support method can be developed into a full-scale web-GIS application. The advantage of using this decision support method is that it allows inspections to be carried out by either skilled volunteers or technicians while ensuring technicians-in-charge that they can systematically evaluate the collected reports. Volunteers can become skilled inspectors by teaming up with technicians for the inspection of hydraulic structures. Technicians can become more aware about local impacts and changes in the structures' status by teaming up with volunteers.
MAppERS experience_ natural processes and preparedness in the societal context
Simone Frigerio, Luca Schenato, Giulia Bossi, Matteo Mantovani, Gianluca Marcato, and Alessandro Pasuto, 2016, MAppERS experience_ natural processes and preparedness in the societal context,
European Geosciences Union - general assembly 2016, Vienna, 17-22 April 2016,
Abstract
Within natural processes responsibilities from central authorities to local levels as first actors of civil ...
Within natural processes responsibilities from central authorities to local levels as first actors of civil protection is a changing pattern. Prevention and preparedness in natural hazards are long-term goals based on capacities of professional volunteers, and improving the awareness of the citizens as local inhabitants. Local people have impacts on their lives but training and involvement towards specific techniques change their role within risk communication and emergency preparedness. A collaborative user environment is useful for emergency response and support in the wake of disasters, feeding updated information on the ground directly to on-site responders. MAppERS (Mobile Application for Emergency Response and Support) is a funded project (2013-2015 Humanitarian Aid and Civil Protection, ECHO A5) based on human role as "crowd-sourced mappers" through smart phone application able to share GPS-localised and detailed parameters. The feedback from testing and the training courses aim to raising public awareness and participation in a networked disaster response. The project implies design and test of smart phone linked with a real-time dashboard platform for rescue services citizens and volunteers of civil protection. Two pilot sites, including trainings on modules functioning control usability and quality of the product. The synchronized platform offers the activity of cloud data collection with a central data dashboard. Information is collected in a context of floods processes, with crowdsourcing action from local population, for proper awareness with own personal flood plan and long-term preparedness. A second context tested pre-emergency actions on field with rescue team, collecting state-of-art and condition of hazards.
Fiber optic distributed strain sensing for open-holes specimen axial tests
Schenato, L.; Pasuto, A.; Garbin, E.; Modena, C.; Palmieri, L.; Galtarossa, A., 2016, Fiber optic distributed strain sensing for open-holes specimen axial tests,
2016 Fotonica AEIT Italian Conference on Photonics Technologies, pp. 1–4, Roma, 6-8 June 2016,
Abstract
We have applied a commercial optical frequency domain reflectometer with high spatial resolution to measure ...
We have applied a commercial optical frequency domain reflectometer with high spatial resolution to measure the strain exerted on an aluminum specimen under tensile strength (open hole) test. The strain profile has been measured until failure by means of an optical fiber and by ten standard electric strain gauges. The matching between the measurement data provided by the two techniques at the strain gauges positions is excellent, except in the proximity of the hole, where the strain gradient is maximum. Due to that, a precise correspondence between optical fiber and strain gauges position near the hole is
mandatory in order to measure the same strain value. The resolution attainable by the optical system, that has not counterpart in any electrical systems, enables an unprecedented spatial sampling, thus allowing a much better characterization of the strain profile along the sample.
Data from https://intranet.cnr.it/people/
