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The Northeastern Italy and the therein Friuli Venezia Giulia (FVG) region are frequently hit by heavy and prolonged precipitations, which cause frequent debris flow and diffused shallow landslides. In this study we focus on a mountain sub-basin of the Fella river watershed, the Uque at Ugovizza, located in the northeastern Julian Alps of the FVG, where a disruptive rainfall-triggered debris flow occurred in 2003.The work aims at pursuing two main targets: (i) implementing a rainfall-runoff and hydro-morphodynamical framework for the analysis of debris flow initiated by intense heavy precipitation; ii) exploiting, for the first time, the flexibility of the GEOframe-NewAge semi-distributed hydrological model simulating high temporal resolution simulations (5-minutes) rainfall-runoff events.The GEOframe-NewAge is an open-source component-based modeling framework, which simulates the entire hydrological cycle of the study area, including the snow melting, the soil water storage and the runoff production and routing in the river network; the model is suitable for the rainfall-runoff event scale simulations in Alpine environment with scarce measurements.Specifically, we describe the results of the calibration and validation procedures applied to four selected intense events occurred in the period 2009-2019. Meteorological data at 5 minutes-step are used to rainfall-runoff modeling, whereas streamflow at 30 minutes is used for the model calibration and validation. Preliminary results show that the models is able to capture the temporal and spatial dynamic of extremes short events, providing satisfying Nash and Sutcliffe coefficient values.

The morphological evolution of tidal flats has been widely investigated in recent years as it represents a very important topic which is highly related to the climate-driven environmental changes. The period over which geomorphological changes can be noted is a multi-year up to pluri-decennial time scale, defined as medium-long period. This work presents a new conceptual model which is able to predict and estimate a limit depth between an erosion condition and a no-erosion condition for tidal flats. The domains of applicability are shallow and confined basins, where tidal flats are characterized by near-horizontal topography, as occurs inside lagoons. The theoretical approach provides a general equation which relates the limit depth of tidal flats to current velocity and critical erosion shear stress. The procedure, followed through to its development, takes into account the important role of the bottom friction dissipation in wind wave generation process for shallow water. The relationship between tidal flat depth, current velocity and critical shear stress is provided in three different configurations, depending on the direction of the wave motion compared to the current. The limit depth compared to the measured depth can suggest if tidal flats tend or not towards an erosion state over a medium-long period. In this sense, the conceptual model provides a relevant contribution to the comprehension of morphodynamics of these important environments. This approach has been validated with its application to a real context and the results are provided in the paper.