215 research outputs found

    Geology and mass movements of the Licetto River catchment (Calabrian Coastal Range, Southern Italy)

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    The paper presents a detailed mass movement inventory map of the Licetto River basin, an intermountain catchment of 50 km2 formed during the Quaternary in response to extensional tectonics dissecting fold-and-thrust belts of the Calabrian Coastal Range (Southern Italy). The map (Main Map) is the result of both an integration between geological and morphological data derived from the visual analysis of aerial photographs at different times and scales, and the collection of new data obtained from multi-temporal field surveys. The study area is affected by a total of 824 mass movements, frequently made by superimposed bodies of different types, states of activity and sizes, including some kilometre-scale Deep-Seated Gravitational Slope. The majority of the mapped landslides, mainly of slide type, involve low-grade metamorphic rocks which also show the exclusive presence of deep-seated gravitational slope deformations. Analysis of the inventory map revealed that 40% of the mapped landslides, often attributable to very slow-moving landslides, can be considered active. The Main Map represents a useful tool for territorial planning and engineering – geological and environmental purposes in this complex geo-structural area, providing a useful contribution for quantitative landslide risk analyses and the design of appropriate risk-mitigation measures

    Full integration of geomorphological, geotechnical, A-DInSAR and damage data for detailed geometric-kinematic features of a slow-moving landslide in urban area

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    AbstractThe reconnaissance, mapping and analysis of kinematic features of slow-moving landslides evolving along medium-deep sliding surfaces in urban areas can be a difficult task due to the presence and interactions of/with anthropic structures/infrastructures and human activities that can conceal morphological signs of landslide activity. The paper presents an integrated approach to investigate the boundaries, type of movement, kinematics and interactions (in terms of damage severity distribution) with the built environment of a roto-translational slow-moving landslide affecting the historic centre of Lungro town (Calabria region, southern Italy). For this purpose, ancillary multi-source data (e.g. geological-geomorphological features and geotechnical properties of geomaterials), both conventional inclinometer monitoring and innovative non-invasive remote sensing (i.e. A-DInSAR) displacement data were jointly analyzed and interpreted to derive the A-DInSAR-geotechnical velocity (DGV) map of the landslide. This result was then cross-compared with detailed information available on the visible effects (i.e. crack pattern and width) on the exposed buildings along with possible conditioning factors to displacement evolution (i.e. remedial works, sub-services, etc.). The full integration of multi-source data available at the slope scale, by maximizing each contribution, provided a comprehensive outline of kinematic-geometric landslide features that were used to investigate the damage distribution and to detect, if any, anomalous locations of damage severity and relative possible causes. This knowledge can be used to manage landslide risk in the short term and, in particular, is propaedeutic to set up an advanced coupled geotechnical-structural model to simulate both the landslide displacements and the behavior of interacting buildings and, therefore, to implement appropriate risk mitigation strategies over medium/long period

    UAV and Structure from Motion Approach to Monitor the Maierato Landslide Evolution

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    In February 2010 a large landslide affected the Maierato municipality (Calabria, Italy). The landslide, mainly caused by a period of prolonged and intense rainfalls, produced a mass displacement of about 5 million mÂł and several damages to farmlands, houses and infrastructures. In the aftermath several conventional monitoring actions were carried out. In the current post emergency phase, the monitoring was resumed by carrying out unmanned aerial vehicles (UAV) flights in order to describe the recent behavior of the landslide and to assess residual risk. Thanks to the potentialities of the structure from motion algorithms and the availability of post emergency reconnaissance photos and a previous 3D dataset, the three-dimensional evolution of the area was computed. Moreover, an experimental multispectral flight was carried out and its results supported the interpretation of local phenomena. The dataset allowed to quantify the elevation losses and raises in several peculiar sectors of the landslide. The obtained results confirm that the UAV monitoring and the structure from motion approach can effectively contribute to manage residual risk in the medium and long term within an integrated geotechnical monitoring network

    The interplay of structural pathway and weathering intensity in forming mass-wasting processes in deeply weathered gneissic rocks (Sila Massif, Calabria, Italy)

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    This paper presents a detailed map (Main Map) showing geology, tectonics, weathering intensity and spatial distribution of landslides in the San Pietro in Guarano study area (about 7.5 km2), located in the north-western sector of Calabria (southern Italy). In this area, deeply weathered high-grade metamorphic rocks and different types/categories of mass movements are widespread. The Main Map, at 1:5000 scale, results from the combination of information gathered via analysis and interpretation of aerial photographs at different times and scales, multi-temporal geostructural and geomorphological surveys, field investigations and mapping of weathering grade in outcrop – through observation of geologically distinctive characteristics and qualitative and semi-quantitative engineering geological tests – integrated by means of the analysis of both weathering profiles on cutslopes and boreholes logs. The Main Map can represent a useful tool for authorities in charge of land-use planning and can profitably concur to typify landslides and to assess quantitative landslide risk

    Weathering grade in granitoid rocks: The San Giovanni in Fiore area (Calabria, Italy)

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    This paper illustrates the methodology and techniques for the compilation of a thematic (engineering) geological map based on detailed mapping of the weathering grade of crystalline rocks occurring in a portion of the Sila Massif close to the San Giovanni in Fiore Village (Calabria, Italy). The map (1:5000 scale), covering an area of about 20 km2, was compiled combining new geological and structural data with the results of a weathering grade field survey. The methodology, used to distinguish and map the weathering grade classes, was performed using qualitative criteria, semi-quantitative tests, and petrographic analysis of weathered rock samples. The Main Map, presented in this paper, aims to provide a useful tool for land-use planning, for geological hazard assessment and engineering perspectives

    Effect of mulching and plant density on out of season organic potato growth, yield and quality.

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    Research was carried out on potato (Solanum tuberosum L., cv. Spunta) growing in the fi eld in the Campania region (southern Italy) in 2007 and 2008, adopting organic farming practices, in order to evaluate the effects of two mulching treatments (black biodegradable fi lm and bare soil) and six plant densities (12.5, 10.0, 8.3, 7.1, 6.2 and, as a control, 5.3 plants per m2) on growth, yield and quality of “new potato” winter-spring and summer-autumn crops. Only in the case of the summer-autumn crop cycle, mulching resulted in a higher yield, plant dry matter and leaf area compared with the bare soil control, while in both crop cycles this latter treatment induced a delay in harvest. The winter-spring cycle gave a higher production of 40-70 mm tubers, while the summer-autumn cycle resulted in a higher vitamin C content. For the winter-spring crop cycle, the plant density of 8.3 plants·m-2 resulted in the highest yield for food-use tubers, whereas the highest production of seed tubers was obtained with a density of 12.5 plants·m-2. The plant density of 8.3 plants·m-2 also resulted in the highest plant dry matter and leaf area. For the summer-autumn crop cycle, the 10 plants·m-2 density gave the highest production of 40-70 mm calibre tubers, as well as the highest plant dry matter and leaf area. In this cycle, the 6.3 plants·m-2 density resulted in the highest production of 70-80 mm calibre tubers. In terms of cost effectiveness, the choice of biodegradable mulching could save the expense of manual weed control and, in the case of the summer-autumn crop cycle, it is also associated with a higher yield. Overall, tuber yield increased with plant density but the fi nal production was also affected by the crop cycle. This may depend on the different environmental conditions and duration which characterized each cultural cycle and, therefore, affected the vegetative development of organic new potatoes

    Geology, slow-moving landslides, and damages to buildings in the Verbicaro area (north-western Calabria region, southern Italy)

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    This paper presents a mass movement inventory map at 1:5000 scale of the Verbicaro area (about 13 km2) located in the Calabria region (southern Italy). The Main Map results from the visual interpretation of aerial photographs, multi-temporal geomorphological field surveys, and field investigations of damage suffered by buildings. Some 53% of the study area is affected by a total of 252 landslides, comprising different types, state of activity, and size. The mapped landslides, mainly complex type, involve low-grade metamorphic rocks; among these, 15% are active and slow-move on pre-existing sliding surfaces. Moreover, out of 492 surveyed buildings, 347 are located on landslide-affected areas and experienced damages covering a broad range of severity levels. The Main Map can represent a useful tool for authorities in charge of land-use planning and urban management and can be used to pursue landslide risk analyses

    Nitrogen fertiliser value of digested dairy cow slurry, its liquid and solid fractions, and of dairy cow slurry

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    An understanding of crop availability of livestock slurry nitrogen (N) is necessary to maximise crop N use efficiency and to minimise environmental losses. Results from field and laboratory incubation experiments suggest that first-year crop availability of slurry N comes mainly from its ammonium fraction because net mineralisation of organic N is often negligible in the short term. A two-year field experiment during 2011 and 2012 in northern Italy was undertaken with several aims: to estimate the N fertiliser value of raw dairy cow slurry, digested dairy cow slurry, and the liquid and solid fractions of the digested slurry, and to verify if applied ammonium recovery was similar both among slurries and between slurries and inorganic N fertiliser (ammonium sulphate). Different fertilisers were applied before silage maize cultivation followed by an unfertilised Italian ryegrass crop. The results showed that ammonium recovery was significantly higher in mineral-fertilised (75%) versus slurry-fertilised (30%) treatments, except in digested slurry (65%). This indicates that ammonium applied with organic materials is less efficient than when applied with mineral fertiliser. For the digested slurry and its liquid fraction, most of the applied ammonium was available to the maize during its application year (55%) due to a low carbon (C)/organic N ratio. The apparent N recovery of the raw slurry and digested slurry solid fraction increased substantially between the first (-1.4%) and second (20%) years, as these materials had high C/organic N ratios; they likely immobilised N for several months post application, producing residual effects during the Italian ryegrass and next maize crops
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