Albina Cuomo

Digital orographic map of peninsular and insular Italy

Abstract Please click here to download the map associated with this article. This paper describes method and contents of the digital orographic map of peninsular and insular Italy, comprising the islands of Elba, Sicily and Sardinia at 1:1,250,000 scale. The map was obtained using a modification of a previous proposal to define mountain orders, starting from the SRTM-NASA digital elevation model (90×90 m cell). The method, comparable to the well known drainage network ordering system, uses the topographic concepts of key contour, key saddle, summit point, prominence, and others. It was implemented in a step-by-step GIS-based procedure in order to automatically identify, delimit and order mountains and hills. The procedure permits the derivation of the parent relationship between orographic entities and organizes the ordered mountains in an orographic hierarchy. The orographic mapping system is able to produce an orographic dataset from DEMs, organize orographic geodatabases and manage mapping tools in many research fields. The map here presented is particularly useful to support interdisciplinary studies in tectonic geomorphology, topo-climatology, regional hydrology and landscape ecology at national scale.

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.

Water Resources Assessment for Karst Aquifer Conditioned River Basins: Conceptual Balance Model Results and Comparison with Experimental Environmental Tracers Evidences

Water resources management, more and more limited and poor in quality, represents a present key issue in hydrology. The development of a community is highly related to the management of the water resources available for the community itself and there is a need, for this reason, to rationalize the existing resources, to plan water resources use, to preserve water quality and, on the other hand, to prevent flood risk. The importance of decision support systems tools, such as hydrological models, generating streamflow time series which are statistically equivalent to the observed streamflow time series, is even more important considering the combination of multiple and complex issues concurring in the definition and optimization of water resources management practices. When river basins with particular features have to be modelled, both traditionally conceptually based models and more recent sophisticated distributed models appear to give not very reliable results. In those cases it is possible to take advantage of a semi-distributed formulation, where every sub-catchment is modelled to account for its features and informations coming from all the sub-catchments are related to each other in order to improve the system description. In this study, starting from the application of a catchment scale modelling tool, we propose a semi-distributed conceptually based framework, able to describe the sub-catchment scale systems hydrological response. The modelling approach is supported by field measurements collected within several seasonal campaigns, that has been set up for the Bussento river basin, located in Southern Italy, well known to hydrogeology and geomorphology scientists for its karst features, characterized by soils and rocks with highly different hydraulic permeability and above all an highly hydrogeological conditioning. The groundwater circulation is very complex, as it will be later discussed, and groundwater inflows from the outside of the hydrological watershed and groundwater outflows toward surrounding drainage systems frequently occur. With the aim to enhance the knowledge of the interaction between the groundwater and surface water and acknowledged the substantial help given by natural isotope tracers experiments to solve hydrological complex systems circulations problems, radon-in water concentrations have also been collected, in a limited number of cross sections, along the upper Bussento river reach.

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.

Using Discharge-Electrical Conductivity Relationship in a Mediterranean Catchment: The T. Ciciriello in the Cilento, Vallo Diano and Alburni European Geopark (Southern Italy)

The paper describes the results obtained from the monitoring activities carried out during the 2012–2013 water year in the T. Ciciriello catchment, located in the terrigenous, hilly, forested area of the Cilento, Vallo di Diano and Alburni National Park-European and Global Geopark. Using rainfall, discharge and electrical conductivity data collected in the catchment stations at daily and 10 min time intervals, hydro-chemical time series analysis were performed in the perspective of hydro-geomorphological regionalization of the headwaters and mountainous catchments. Analysis of the data collected during this first monitoring year allowed us to compute reliable rating curves at selected stream flow stations, perform a good fit of the stream flow discharge-electrical conductivity relationship, apply an useful mixing model for hydrograph separation. This last was based on the water end-members referred to the specific runoff sources and flow paths, previously defined and mapped by hydro-geomorphological surveys and finally detected by the monitoring activity.