1,720,974 research outputs found
Relationships between geo-hydrological processes induced by heavy rainfall and land-use: the case of 25 October 2011 in the Vernazza catchment (Cinque Terre, NW Italy)
No full textOn 25 October 2011, heavy rainfall affected an area of ca. 1000 km2 between eastern Liguria and northern Tuscany (northwest Italy). The event caused floods, hundreds of shallow landslides, four casualties and severe structural and economic damage in Monterosso and Vernazza villages. The distribution of geo-hydrological processes triggered by rainfall in relation to land-use was analyzed in the Vernazza catchment. Both, an inventory map of geo-hydrological processes and a land-use map were prepared through air photo-analysis and field surveys; a derivative map combining these two outputs provides insight into the relationships between geo-hydrological processes and land-use. The density of shallow landslides (n/km2) and the frequency of erosional processes (%) are higher in terraced areas compared to other land-use classes. The study highlights the high vulnerability of agricultural terraces which, over the centuries, have been a fundamental tool for the prevention and control of erosional processes and slope instability
Valutazione della vulnerabilità intrinseca dell’acquifero carsico nel Bric Tampa (Alpi Liguri): risultati preliminari
No full textUse of Remote Sensing data, terrain analysis and stochastic modeling to predict current and future flood risk in a small Mediterranean catchment (T. Teiro, Italy)
No full textTHE SOILS OF PORTOFINO PROMONTORY (NW ITALY): DISTRIBUTION, GENESIS AND PALAEOENVIRONMENTAL IMPLICATIONS.
No full textThe coverage of detailed soil maps is commonly limited in Italy, and the available regional soil inventories are obviously not adequate for local land planning strategies. The aim of this research is to map soil units using a Geographical Information System (GIS) approach in the Portofino regional park. Soil micromorphology has been selected as support to the laboratory routine analyses for studying some representative benchmark profiles in order to explain their genesis and to assess their palaeoclimatic significance. The spatial distribution and variability of the most extensive soil types were analysed using a GIS approach and are presented in a 1:10,000-scale soil map with a descriptive legend. We identified six RSGs: Cambisol, Regosol, Leptosol, Luvisol, Acrisol, and Umbrisol. This GIS database was then used to produce three derived maps: soil erodibility factor, spatial distribution of soil organic carbon (SOC) and soil hydrological groups. Deep and highly weathered soils were identified on an ancient erosional surface. These soils are relict palaeosols, products of longer pedogenesis, and are no longer affected by active processes. Polygenetic development of these palaeosols was underlined by micromorphological studies showing relict features reflect climate conditions typical of past interglacial periods which were warmer and more humid than today
Applicazioni GIS per lo studio dell’erodibilità dei suoli nel Parco Naturale di Portofino (Liguria, Italia)
No full textAssessment of calanchi and rill-interrill erosion susceptibility in northern Liguria, Italy: A case study using a probabilistic modelling framework
No full textSoils are a vital part of the natural environment and one of the most important natural resources. The EuropeanMediterranean Regions are particularly sensitive to soil degradation. Especially in Italy many landscapes areprone to water related soil erosion processes such as rill-interrill erosion (sheet erosion), gullies and complexprocesses forming“calanchi”corresponding to the English term“Badlands”. Calanchi develop preferentially onPlio-Pleistocene deposits, which are highly susceptible to aquatic erosion processes. This study focusses on theassessment of rill-interrill erosion as well as calanchi erosion forms and features in previously none or very little-studied areas of the Langhe-Roero and Monferrato, located in the Liguria and Piedmont Region, NorthernApennines, Italy. In this study we assess the driving factors and the spatial distribution of rill-interrill andcalanchi erosion processes using a geostatistical/geostochastic modelling framework. Therefore, a MaximumEntropy Model, a Generalized Linear Model and a Boosted Regression Tree approach were applied. As in-dependent environmental variables we selected DEM based morphometric information as well as pedologic, andgeologic input data. Moreover, we explore remote sensing techniques to derive information on the vegetationdensity and vitality. The stochastic models applied show, that the two very different soil erosion phenomena canbe differentiated well with the chosen stochastic techniques. The main drivers controlling the spatial distributionof aquatic soil erosion in the study area are soil type, slope, elevation and topographic wetness index. The resultsof the MaxEnt and BRT model were confirmed by the GLM application in terms of the significance of predictorvariables. Generally, the models show an acceptable to excellent performance with BRT and GLM outperformingMaxEnt. The single independent variable response curves gave valuable insights into the process triggering theerosion forms. We were able to clearly differentiate between the processes looking at the response curves thatshow reasonable characteristics with all applied models
Assessment of land cover changes on flood generation in a small Mediterranean catchment using an SCS-CN modeling approach: A case study in the Vernazza catchment, Cinque Terre National Park, Liguria, Italy.
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