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Coronavirus disease 19 (COVID-19) is an infectious disease caused by the SARS-CoV-2 virus, which is responsible for the ongoing global pandemic. Stringent measures have been adopted to face the pandemic, such as complete lockdown, shutting down businesses and trade, as well as travel restrictions. Nevertheless, such solutions have had a tremendous economic impact. Although the use of recent vaccines seems to reduce the scale of the problem, the pandemic does not appear to finish soon. Therefore, having a forecasting model about the COVID-19 spread is of paramount importance to plan interventions and, then, to limit the economic and social damage. In this paper, we use Genetic Programming to evidence dependences of the SARS-CoV-2 spread from past data in a given Country. Namely, we analyze real data of the Campania Region, in Italy. The resulting models prove their effectiveness in forecasting the number of new positives 10/15 days before, with quite a high accuracy. The developed models have been integrated into the context of SVIMAC-19, an analytical-forecasting system for the containment, contrast, and monitoring of Covid-19 within the Campania Region. [ABSTRACT FROM AUTHOR]

In many geotechnical applications, especially in the study of weather-induced landslides, a reliable soil hydraulic characterization in unsaturated conditions is required. Currently, the experimental techniques that neglect the hydraulic hysteresis represent the greatest limitation to landslide forecasting. In this paper, a procedure to obtain an unsaturated soil hydraulic characterization on natural pyroclastic samples is proposed and verified. The approach enables the evaluation of the soil hydraulic properties along the main drying path and wetting/drying cycles to fully quantify the effects of the hydraulic hysteresis. Pyroclastic soil samples collected at a test site at Mount Faito in the Campania region (southern Italy) were tested. The experimental investigation consisted of a sequence of testing phases: a constant-head hydraulic conductivity test, a forced evaporation test followed by several wetting–drying cycles, and a drying test in a pressure plate apparatus. The hysteretic model proposed by Parker and Lenhard (1987) was adopted to fit the data, while inverse modelling of the forced evaporation tests allowed to derive the model parameters. Therefore, the main drying and wetting branches and the soil response to drying and wetting cycles from any reversal point were reproduced with the model, which suitably described the hysteretic behaviour of the pyroclastic soil under all conditions and along all paths. [ABSTRACT FROM AUTHOR]

Thickness and stratigraphic settings of soils covering slopes potentially control susceptibility to initiation of rainfall-induced shallow landslides due to their local effect on slope hydrological response. Notwithstanding the relevance of the assessment of hazard to shallow landsliding at a distributed scale by approaches based on a coupled modelling of slope hydrological response and slope stability, the spatial variability of soil thickness and stratigraphic settings are factors poorly considered in the literature. Under these premises, this paper advances the well-known case study of rainfall-induced shallow landslides involving ash-fall pyroclastic soils covering the peri-Vesuvian mountains (Campania, southern Italy). In such a unique geomorphological setting, the soil covering is formed by alternating loose ash-fall pyroclastic deposits and paleosols, with high contrasts in hydraulic conductivity and total thickness decreasing as the slope angle increases, thus leading to the establishment of lateral flow and an increase of pore water pressure in localised sectors of the slope where soil horizon thickness is less. In particular, we investigate the effects, on hillslope hydrological regime and slope stability, of irregular bedrock topography, spatial variability of soil thickness and vertical hydraulic heterogeneity of soil horizons, by using a coupled three-dimensional hydrological and a probabilistic infinite slope stability model. The modelling is applied on a sample mountain catchment, located on Sarno Mountains (Campania, southern Italy), and calibrated using physics-based rainfall thresholds derived from the literature. The results obtained under five simulated constant rainfall intensities (2.5, 5, 10, 20 and 40 mm h−1) show an increase of soil pressure head and major failure probability corresponding to stratigraphic and morphological discontinuities, where a soil thickness reduction occurs. The outcomes obtained from modelling match the hypothesis of the formation of lateral throughflow due to the effect of intense rainfall, which leads to the increase of soil water pressure head and water content, up to values of near-saturation, in narrow zones of the slope, such as those of downslope reduction of total soil thickness and pinching out of soil horizons. The approach proposed can be conceived as a further advance in the comprehension of slope hydrological processes at a detailed scale and their effects on slope stability under given rainfall and antecedent soil hydrological conditions, therefore in predicting the most susceptible areas to initiation of rainfall-induced shallow landslides and the related I-D rainfall thresholds. Results obtained demonstrate the occurrence of a slope hydrological response depending on the spatial variability of soil thickness and leading to focus slope instability in specific slope sectors. The approach proposed is conceived to be potentially exportable to other slope environments for which a spatial modelling of soil thickness would be possible. [ABSTRACT FROM AUTHOR]

The term debris flow is associated with a wide variety of phenomena as debris slides, debris torrents, debris floods, mudflows, mudslides, hyper-concentrated flows and lahars (in volcanic slopes). In historical times, they frequently occurred in Campania Region (Southern Italy) producing damage and casualties. In this paper, more than 200 events described as "debris flow" between 1924 and 2020 were collected. They are mainly located in the central sector of the region, which is characterized by pyroclastic deposits resting on steep carbonate and volcanic slopes and highly prone to hydrogeological hazards. Debris flow events registered in the region were classified as "gravity processes" (flow-like landslides, FL) or "fluvial processes" (flash floods, FF). This classification is fundamental for designing effective early warning systems and risk mitigation plans, since the two phenomena are triggered by different types of rainfall events and are responsible for damages of different magnitude. In this study, a large rainfall database was explored to identify the time scales and seasonality of the two classes of rainfall events, respectively triggering the two phenomena. [ABSTRACT FROM AUTHOR]

This paper shows the results of a study aimed at quantitatively estimating—in terms of direct (repair) costs, at large scale (1:5000)—the slow-moving landslide risk to a road network assumed as undamaged as well as the consequences to the same network in damaged conditions. The newly conceived methodological approaches address some challenging tasks concerning (i) the hazard analysis, which is expressed in terms of probability of occurrence of slow-moving landslides with a given intensity level that, in turn, is established based on empirical fragility curves, and (ii) the consequence analysis, which brings to the generation of time-dependent vulnerability curves. Their applicability is successfully tested in a case study in the Campania region (southern Italy) for which both very high-resolution DInSAR data and information gathered from in situ surveys on the severity of damage sustained by the selected road sections are available. Benefits associated with the use of the obtained results in informed decision-making processes are finally discussed. [ABSTRACT FROM AUTHOR]

In the last ten thousand years, the explosive activity of some volcanic centers has blanketed with pyroclastic soils the major part of Campania Region, Southern Italy. Experience shows that the sloping deposits may be mobilized by long-lasting precipitations, leading to rapid and sometimes catastrophic flow-type slope movements. This paper summarizes the present knowledge on this subject based on the results of both laboratory tests and experiments and on a review of the main data provided by field surveys. In particular, a careful examination and analysis of the available elements highlight the key role played by lithological and morphological details on failure and post-failure mechanisms, thus affecting landslide hazard. In fact, it is shown that deposition mode and grain size, slope angle, and morphology strongly affect the type of post-failure movement, which may take the features of a debris avalanche, of a debris flow, or of a flowslide and may lead (or not) to soil liquefaction, a mechanism that strongly affects both displacement rate and run-out. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the divides in separate waste collection (SWC) between Campania and Veneto from a twofold perspective that considers both intensity (the size of the gap) and inequality (the differences among the SWC distributions across municipalities). In the framework of Kapp's social cost theory, the Recentered Influence Function regression allows an evaluation of the amount of territorial divides that are accounted for by the: (i) regional component, which captures the extent to which regional authorities transpose national legislation into programs of waste management; (ii) municipal component, which explains the effect of the operational strategies adopted by each local authority to guarantee an adequate performance. As the best-performing region in Italy, Veneto reached an average SWC level far superior to that of Campania in 2012, and more importantly, most of its municipalities exceeded the 65% target set by Legislative Decree 152/2006 with a smaller variability within the region. However, a more detailed analysis shows that the policies and strategies for waste management set by the regional authority in Campania should be more effective at the initial stage, but are partly held back by the successive implementation steps controlled by each municipality. One of the primary deterrents of reaching a better performance in waste management in Campania lies in the weakness of its institutions, which makes the region more vulnerable with a large amount of heterogeneity in waste management performance across municipalities. [ABSTRACT FROM AUTHOR]

The paper reports a study on the capillary barrier effects in a layered pyroclastic deposit with different permeabilities. During prolonged low intensity rainfall, such phenomena lead to a significant increase in saturation in the least permeable soil layers. This is a common situation on the slopes of Pizzo D'Alvano (Campania, Southern Italy) where severe landslides were triggered in May 1998, and in many other geological environments where geological, sedimentological, geomorphologic and pedological processes may have produced a sequence of soils with different hydraulic conductivity. The results of laboratory column infiltration tests and evidence of capillary barrier effects are presented and used in the calibration of numerical unsaturated flow models. [ABSTRACT FROM AUTHOR]