Obstructions at bridge can exacerbate flood hazard: when woody debris occlude a bridge, backwater increases, and sometimes a temporary reservoir can form. If the condition for the collapse of the jam exists, the phenomenon can evolve into a dam break flow resulting in an increase in downstream discharge or a steepening in the flow hydrograph. A rigorous description of backwater formed by debris at the bridge, and more generally of the interaction between flood and structure, is still a challenge and only few studies focus on the breakage phase and its consequence on flood dynamic. Unfortunately, analyzing the hydraulics of so many localized situations within a large area in detail would involve considerable modeling and calculation costs. Therefore, treatment methods are desirable that provide correct results in terms of the reference hydraulic variables for assessing the hazard without the need to model extremely local phenomena. The purpose of this study is to evaluate the possibility to reproduce an observed or estimated backwater by the use of an equivalent roughness at the place of the bridge and simulate the breakage phase by a sudden variation of its value. The method, applied to the numerical reconstruction of the experimental tests of dam break performed by the Waterways Experiment Station in 1961, has provided results that overlap well with the experimental values. Furthermore, it was applied to the reconstruction of the historical flood occurred in the Soverato river (Calabria, Italy). It did not require local grid refinement and provided results faithful to flood marks.
Landscape configuration and forest structure assume an increasing importance as determinants of animal communities. This paper focused on nocturnal Lepidoptera inhabiting alder patches in the Sila National Park, Italy. According to their shapes, patches were divided into linear and compact ones to disentangle the roles of forest structure and landscape configuration in determining the composition of nocturnal Lepidopteran communities at different observation scales. We used the Mann–Whitney test for medians and Shannon diversity, equitability, Fisher’s alpha, and nestedness to test differences among moth communities. We found that compact patches inhabited richer and more abundant communities. The abundance-based Correspondence Analysis showed moth communities clustered according to woodlot shape, except a compact woodlot with a linear-like moth community because it was entirely surrounded by grasslands. Percentage of forested area and abundance and composition of communities were positively correlated at 50 and 200 m buffers, while correlations were absent at smaller and larger buffers. Our results demonstrated that a width of 50 m may not be sufficient to give proper functionality to the wooded area, at least for moths. As a consequence, planning of forest restorations should consider the importance of increasing the structural habitat continuity at larger scales.
Monitoring the stability of a slope is one of the non-structural measures aimed at reducing the risk of landslides. Displacement detection is now possible through numerous monitoring techniques, including remote sensing and ground-based solutions. In particular, in-situ monitoring allows some advantages related to using low-cost instruments whose communication can be facilitated by IoT technologies. In this chapter, we illustrate an example of an intelligent system for the integrated monitoring of the main landslide bodies of Gimigliano (CZ), southern Italy.The station includes clusters for monitoring deep movements and piezometric levels, as well as for urban structures through specific sensors and a network of sensors for topographic surface monitoring. The system was designed to be almost fully automatic and oriented to support near real-time warning activities. The data recorded by the deep and surface monitoring instruments confirm that the study area is affected by complex phenomena requiring long-term on-site monitoring.Specifically, analysis of the deep movements revealed some critical events during spring 2022 and summer 2023 that resulted in positive and negative millimetric deformations, measured by the tilt meters installed in correspondence with the monitored sites. Surface topographic analysis indicates displacement rates of 2.5–5 cm/year.
Landscape configuration and forest structure assume an increasing importance as determinants of animal communities. This paper focused on nocturnal lepidoptera inhabiting alder patches in the Sila National Park, Italy. According to their shape, patches were divided into linear and compact ones to disentangle the role of forest structure and landscape configuration in determining the composition of nocturnal lepidopteran communities at different observation scales. We used the Mann-Whitney test for medians to Shannon diversity, Equitability, Fisher’s alpha, and nestedness to test differences among moth communities. We found that compact patches inhabit richer and more abundant communities. The abundance-based Correspondence Analysis showed moth communities clustered according to woodlot shape, except a compact woodlot having a linear-like moth community because entirely surrounded by grasslands. Percentage of forested area and abundance and composition of communities are positively correlated at 50 and 200 m buffers, while correlations are absent at smaller and larger buffers. Our results demonstrated that a width of 50 m may not be sufficient to give proper functionality to the wooded area, at least for moths. As consequence, planning of forest restorations should consider the importance to increase structural habitat continuity at larger scales.