Domenico Guida

Classification and mapping of the ecoregions of Italy

Ecological regions or ecoregions derive from ecological classification of land and represent broad and discrete ecologically homogeneous areas within which natural communities and species interact with the physical elements of the environment. The aim of this paper is to define the ecoregions of Italy, southern Europe, based on a robust methodological process for classification and mapping. The ecoregions of Italy comprise 2 Divisions, 7 Provinces, 11 Sections and 33 Subsections and constitute the first comprehensive ecological classification of the country that integrates accurate and updated cartographies and knowledges on climate, vegetation, land units and biogeography. This classification has the strength to be adopted as a proper framework for ecological modelling, biodiversity conservation policies and sustainable territorial planning at the national and subnational level.

Geomorphological and dendrochronological analyses of a complex landslide in the Southern Apennines

Abstract. Complex landslides, capable of reactivation, are typical slope movements in high relief areas. Due to their distribution, size and kinematics, these landforms represent a major hazard, posing a high risk to populations, settlements and infrastructures. This paper integrates geomorphological analyses, instrumental measurements and dendrochronological approaches in assessing a large, reactivated landslide system on the southern piedmont of Monte Sirino (southern Italy). The landslide system is associated with weak geological structures, earthquake activity, and rapid recent incision of the mid‐Pleistocene Noce lake deposits. Potential reactivation triggers include a higher regional annual rainfall, one of the highest in southern Italy, and more frequent heavy snowfalls in recent decades. Reactivation of the Sirino landslide system has important implications for the motorway connecting Salerno and Reggio Calabria, which crosses it. The results of our study show that the slide is reactivated with an almost decadal frequency and that major reactivations are correlated to prolonged snowfall, which occurs with increasing frequency in the southern Apennines. The last observation suggests the need for similar studies on the behaviour of other landslide systems in the southern Apennines, performing integrated approaches such as geotechnical and dendrogeomorphological analysis.

Influence of the variation between static and kinetic friction on stick-slip instability

Abstract A theoretical analysis of stick-slip instability is proposed with reference to systems with one degree of freedom. The friction force is approximated with a piecewise linear function, i.e. straight line segments with a suitable slope, assuming that the static friction coefficient is greater than the kinetic one. For the generic system belonging to the class in question, the stick-slip instability region is located on a suitable dimensionless map.

Land units map of Italy

In this paper we present the land units map of Italy, covering an area of ca. 300,000 km2 between 47°05′ N–35°29′ N and 6°37′ E–18°31′ E. The map was created by means of a Geographic Information System (GIS) and is based on the overlay of various thematic maps according to a hierarchical classification. The map scale is 1:250,000, with a minimum mapping unit of 50 ha. The GIS integration of different layers, covering the main environmental components (climate, lithology and geomorphology), resulted in a number of hierarchically arranged land units, homogeneous in terms of biotic potential and ecological processes. These units highlight the role of physical determinism in characterizing the Italian territory with a high degree of environmental heterogeneity. The proposed land classification scheme could be taken into consideration when planning initiatives aimed at surveying, monitoring, managing and sustainably developing the territory.

Landslide Hazard and Risk in the Dessie Town Area (Ethiopia)

This paper presents the results of a geo-environmental study carried out in the urban area of Dessie town, one of main urban centres of Ethiopia with 200,000 inhabitants. In this area, landslides heavily interact with a disorderly expanding human settlement, inducing high risk conditions for human lives, buildings, infrastructures and economic activities. Based on a detailed geological and geomorphological field survey and mapping, a GIS-based analysis of landslide susceptibility has been applied to the Dessie basin, one of the “hanging” tectonic depressions located along the western Afar margin. Landslide hazard and risk maps were successively produced for the central sector of Dessie town. The landslide risk map and the related report will constitute the starting point for a possible plan of risk mitigation in the urban area of Dessie.

At which time step do we need to monitor the stream hydro-chemistry properties for low flow characterization?

The low flow regime features are frequently described in terms of global indices and, among these, the most relevant are the baseflow index and the flow duration curve. Low flow indices have to be computed from observed streamflow data, but monitoring campaigns are time and cost consuming activities. The aim of the present study is then to identify the impact of the monitoring time step resolution, with particular reference to the low flow regime. To the scope, the hydro-chemographical dataset recorded, during a two year monitoring campaign, at the T. Ciciriello experimental catchment, a 3km2 watershed located in the Cilento, European and Global Geopark (Southern Italy), have been analyzed. Water depth (D), discharge (Q), electrical conductivity (EC) and rainfall time series are available. Assuming the daily time scale as the baseline, a fictitious monitoring experiment has been performed, sampling the observed daily time series at different multiple-day time steps. Main global statistic are computed for the different fictitious series and compared to the daily series. The baseflow patterns, filtered with the use of a mass balance method, appear statistically similar and the differences in terms of low flow indices fall within a 10% range.

Hydrological Modelling For River BasinManagement In A Highly Hydro-geologicalConditioned Environment

Water resources management represents a present key issue in hydrology, and hydrological models generating streamflow time series are useful tools in this field. It is possible to refer, in the extreme, to lumped or fully distributed approaches, but when river basins with particular features have to be modeled it is possible to take advantage of a semi-distributed formulation. In this study we propose a semi-distributed conceptually based modeling approach, supported by field measurements collected within several seasonal campaigns, that has been set up for the Bussento river basin, located in southern Italy, characterized by soils and rocks with highly different hydraulic permeability and above all a highly hydro-geological conditioning. The proposed approach, which joins together all hydraulic, hydrological and geological data, is able to reproduce the river discharge mean characteristic.

On the friction-position control relationship

Abstract A theoretical analysis of the dynamic behaviour of mechanical systems characterized by coupled elements subjected to friction force from the sliding surface is proposed. With reference to systems with one degree of freedom and approximating the friction force as a piecewise linear function, i.e. straight line segments with a suitable slope, the positioning errors in the stop phase are studied. Dimensionless analytical relations used to predict the size of positioning errors and dimensionless diagrams are provided.

Hydraulic modeling of flood pulses in the Middle Bussento Karst System (MBSKS), UNESCO Cilento Global Geopark, Southern Italy

Karst systems provide water for domestic and industrial uses and for generating hydropower, but they can also create fluvial hazards, such as upstream back-flooding and downstream karst flash-flood events. However, these hazards are difficult to foresee due to the complex recharge-discharge processes as well as the lack of information on the inside of the system, which has often not been completely surveyed by speleologists or explored by boreholes. To overcome these difficulties, hydro-chemical data from the monitoring system in the Middle Bussento Karst System (MBSKS), one of the first Experimental Karst Systems in southern Italy, were recorded and previously discussed. Based on shared background in flood karst hydraulic modeling, this paper describes the conceptual premises and rationale of a general-purpose hydraulic model that is suitable both for the MBSKS and for other Mediterranean, multi-recharge, mature, conduit-dominated karst systems. To test the reliability of the model, simulations of time-space behavior and response are performed using natural and artificial flood pulses “as tracers”, considering a “pulse” as a significant variation in water quantity and/or quality. The results of the model explain the interactions between allogenic, autogenic and anthropogenic recharges from differentiated sources and phreatic conduit systems. These results also clarify the overall response of karst springs at typical time scales of flood pulses.

Monitoring Activity at the Middle Bussento Karst System (Cilento Geopark, Southern Italy)

This paper deals with the results of the monitoring activities carried out in the Middle Bussento Karst System (MBSKS) during fall 2012. The MBSKS is located in the Cilento, Vallo Diano and Alburni National Park—European Geopark in the south of Italy. Results discussed in this paper are part of a larger monitoring program which has started in 2010 in an attempt to apply the European Water Directive to the protected areas. Since fall 2012, the program has been focused on the monitoring of the MBSKS. This phase has been aimed to improve knowledge of the hydro-dynamic behavior of the mature MBSKS, differentiating outputs coming from anthropogenic, autogenic and allogenic sources. During this phase two stations, located at one of the stream sink input and at the output of the system, have been used. Results obtained have confirmed some known mature karst systems behavior as such as: flushing effect, piston flow and very fast input-output response. Additional analysis has provided enough information to outline a hydraulic model of the system. Furthermore lessons learnt during this period have led to the implementation of an upgraded monitoring system that is now under completion.