Search

Forest fires are one of the most dangerous events, causing serious land and environmental degradation. Indeed, besides the loss of a huge quantity of plant species, the effects of fires can go far beyond: desertification, increased risk of landslides, soil erosion, death of animals, etc. For these reasons, mathematical models able to predict fire spreading are needed in order to organize and optimize the extinguishing interventions during fire emergencies. This work presents a new system to simulate and predict the movement of the fire front based on free and open source Geographic Information System (GIS) technologies and the Rothermel surface fire spread model, with the adjustments made by Albini. We describe the mathematical models used, provide an overview of the GIS design and implementation, and present the results of some simulations at Etna volcano (Sicily, Italy), characterized by high geomorphological heterogeneity, and where the native flora and fauna may be preserved and perpetuated. The results consist of raster maps representing the progress times of the fire front starting from an ignition point and as a function of the topography and wind directions. The reliability of results is strictly affected by the correct positioning of the fire ignition point, by the accuracy of the topography that describes the morphology of the territory, and by the setting of the meteorological conditions at the moment of the ignition and propagation of the fire.

Biomasses are materials of organic origin that can be used for the production of energy. Among the renewable energy sources, a prominent role is played by woody biomass, which can be retrieved from existing forests or plantations governed in short or middle rotation coppice, the so-called Short and Medium Rotation Forestry. The main environmental benefit resulting from the use of wood biomass consists in the fact that the amount of carbon dioxide released during their combustion process is the same as that absorbed during the development phase. Here, we propose a procedure to manage the traceability of short biomass chains and to schedule the activities for mobile forest construction sites using free and open-source GIS technologies. Firstly, we created a spatial DB to manage the areas where the cutting and logging activities are performed. Then, we overlapped the boundaries of areas with the cadastral sheets to ensure the biomass comes from short chain, i.e., within the range of 70 km from the position of the central. To plan the number of working days required and make an estimation of the production, the total area of the lots, the land clearing, and the net area were calculated. Finally, depending on the characteristics of wooded areas, the type of system to be used for the business of cutting and logging was evaluated. This work demonstrates how GIS allows a fast traceability of short biomass chains and an estimation of the production by improving the efficiency and effectiveness of biomass resource assessment.

This study focuses on the determination and examination of both the Land Surface Temperature (LST) and the atmospheric temperature in the city of Catania Sicily (Italy), through freely available satellite remote sensing images from the Sentinel-2 and MODIS missions. Satellite images were processed as raster data in free and open-source GIS environments. The GIS software allows the retrieval, processing of the satellite images for the estimation of the LST and the atmospheric temperature with a very coarse spatial resolution. In particular, the proposed procedure allows increasing the spatial resolution of satellite images, from 250 m (LRES) to 10 m (HRES) through the principle of “Disaggregation of thermal images”. The analysis provided georeferenced maps which show the LST, as well as the atmospheric temperature within the investigated area with a very fine resolution, 10 m. Such spatial resolution reveals evident correlations between areas with different urban densities and their microclimate. An important result of this study is that significant LST differences can be observed during both day (15–17 °C) and night (2–3 °C) between green and built-up areas. The outcomes of this study highlight the effectiveness of the combined use of satellite remote sensing and GIS for analyzing the thermal response of urbanized areas with different built density.

The objective of this work is the safety analysis of complex crossroads, together with the evaluation of efficiency and performance, in terms of saving time, for a mobile stop-and-go survey. We propose high accuracy digital measurements of all the elements present in order to analyze the critical factors and be able to redesignroad intersection and/or reposition of road signs.The mobile laboratory of “Geomatica”of the University of Catania (Italy) has been set up to start an innovative digital survey ofan unsafe crossroad located in Giarre (Sicily). The set up of this mission includesa Fiat Ducato, a notebook with bluetoothmodule, a Terrestrial Laser Scanner (TLS) Leica P20, and a self-leveling platform Scan&Go with relative accessories (power cable and tool to attach and fix it on the roof of the vehicle).Cutting planes of the TLSpoint cloud locatedat 1.1 and 2 meters height demonstrate that there is a condition of poor visibility of the intersection near the stop line, revealing unsafe visibility condition. The results achieved show that the use of laser scanner for safety analysis in road intersections appears to be an effective, complete and precise approach, allowing a clear improvement in the acquisition speed compared to other methods.

Geophysical measurements provide a massive data source to investigate the behaviour of active volcanoes like Mt. Etna (Sicily, Italy). Here we present a new interface to visualize gravity variations, observed through time-lapse measurements, based on the Google Maps service, a choice motivated by its ease of use and the user-friendly interactive environment it provides. The tool allows to choose among the benchmarks of the Etna's gravity network, as well as to quickly visualize the gravity data since 1994. The integration of these measurements into a coherent visualization framework is important for their practical exploitation, providing a powerful environment for a quick and efficient processing of data time series.

In Italy, at present, the cadastral cartography and every related service to citizen are managed by the Revenue Agency. It is important to remember the era of cadastral mapping formation, which has undergone many changes over time, dictated by the continuous evolution in the survey discipline.It is important to remember that the original maps were produced in the early 1900 with the Cassini-Soldner Projection on the Bessel's Ellipsoid. In the time, the ancient analogical methodologies for surveying and cartographic production have been gradually replaced with new analytical procedures and digital technologies that give higher accuracy, while new detection techniques and the GPS, in particular, introduced to the definition of a new International Geodetic Datum WGS84.During the eighties a process of digitalization of the cadastral cartography began, also introducing the first computerized procedures for the preparation of the deeds to update the land register. For these causes, the cadastral maps do not have a high metric accuracy and above all they cannot be superimposed on the more recent maps and orthophotos referred to the WGS84 International Datum. Therefore it is necessary and of scientific interest to explore the accuracy of the cadastral maps and its variations due to the digitalization process and the numerous updates made over time.

Satellite-derived data, including an estimation of the eruption rate, proximal volcanic deposits, lava flow morphometric parameters (area, maximum length, thickness, and volume) are here provided for the eruptions occurred at Mt Etna between January 2011 and December 2015. These eruptions took place at the New Southeast Crater (NSEC), the youngest of the summit craters of Etna. The time-series analysis of multispectral SEVIRI images(timeresolution of 15 min)provided an estimation of event magnitude and intensity of the effusive material erupted during effusive events, while tri-stereo Pleiades images (spatial resolution of 50 cm) gave the pre-eruptive topography and the topographic changes due to the volcanic deposits. The level of accuracy of these estimates suggests that the integration of multi-platform remote sensing products represents a new potential of merging capabilities to enable a more comprehensive response to effusive crises.

We proposes a new procedure tohighlight archaeological elements using satellite remote sensing. The processing of multispectral satellite imagesconsists in the exploitation of linearequations of the initial spectral bands with the aimof generating accurate and precise raster data that can be used as input for an object classification. The proposed methodology has been tested in an archaeological area on the north-west flank of Etna volcano (Sicily, Italy).

A rockfall analysis at one of the most relevant cultural heritage sites of northeastern Sicily (Italy) is presented herein with the aim of assessing the hazard arising from the unstable conditions of the rock cliff of Taormina city, upon which the Saracen Castle is perched on its top. Several rockfalls affected this area in the latest years, representing a serious threat for the safety of inhabitants and tourists. Therefore, the qualitative Evolving Rockfall Hazard Assessment (ERHA) was applied for the hazard zonation, supported by rock mass surveys and Terrestrial Laser Scanner prospecting. Kinematic analysis revealed that the unstable rock failure patterns are represented by planar/wedge sliding and toppling, while simulation of potential rockfalls allowed studying the impact of future events in terms of trajectory and energy. This is higher at the foot of scarps and in steeper sectors, where the application of ERHA identified a critical zone close to the inhabited center, which is one of the main elements at risk, along with a pedestrian tourist path. Achieved results represent a starting point for the definition of risk management strategies and provide a scientific contribution to the study of hazard and risk arising from rockfall occurrence.

This paper describes a variety of modern geomatics techniques for the detection and survey of emerging archeological structures in Sicily. The case study presented in this work is related to an archaeological site that lies on the north-western flank of Etna, the highest active volcano of Europe. For the field survey, we used an Unmanned Aerial Vehicle (UAV) equipped with a high-resolution camera and a GPS for the ground control points. In addition, we produced a Digital Surface Model (DSM) and several detailed orthophotos of the detected objects. The geomatic approach here adopted made significant contributions to our reconstruction of the past settlement located between “Balze Soprane” and “Santa Venera” districts.

A wide series of events requires immediate availability of information and field data to be provided to decision-makers. An example is the necessity of quickly transferring the information acquired from monitoring and alerting sensors or the data of the reconnaissance of damage after a disastrous event to an Emergency Operations Center. To this purpose, we developed an integrated GIS and WebGIS system to dynamically create and populate via Web a database with spatial features. In particular, this work concerns the gathering and transmission of spatial data and related information to the desktop GIS so that they can be displayed and analyzed in real time to characterize the operational scenario and to decide the rescue interventions. As basic software, we used only free and open source: QuantumGIS and Grass as Desktop GIS, Map Server with PMapper application for the Web-Gis functionality and PostGreSQL/PostGIS as Data Base Management System (DBMS). The approach has been designed, developed and successfully tested in the management of GIS-based navigation of an autonomous robot, both to map its trajectories and to assign optimal paths. This paper presents the application of our system to a simulated hydrological event that could interest the province of Catania, in Sicily. In particular, assuming that more teams draw up an inventory of the damage, we highlight the benefits of real-time transmission of the information collected from the field to headquarters.

The flight planning for Unmanned Aerial Vehicles (UAVs) is extremely useful both in terms of planimetry and altimetry. Regarding the planimetry, it is needed to reach and operate on the region of interest, while for the altimetry, it is functional to plan the flight altitude as function of the obstacles along the navigation path. In this paper we propose an innovative approach for the construction of a georeferenced map of the obstacles based on Geographic Information Systems (GIS) technologies. In this way the path planning for the UAV navigation can be accurately managed by defining precise flight plans on a cartographic support where the obstacles are represented in a three-dimensional way. The employment of free and open source software only, makes the approach widely usable and customizable.

After the observation of cases of malignant pleural neoplasm in Biancavilla (Catania, Italy), a new asbestiform fiber, named fluoro-edenite (NaCa2Mg5(Si7Al)O22F2), was found in a stone quarry use for local building industry and in the lung tissue of an 86 years old woman who died from pleural mesothelioma. As a consequence the Italian Ministry of the Environment has included the Biancavilla site in the National Priority List. In this study, a point of view on the results from a large scale environmental monitoring program conducted for the implementation of the site investigation is presented. The obtained dataset from the environmental monitoring program results in more than 3,000 values of concentration of asbestos like fibers and fluoro-edenite fibers in air, water and top soil. These data are spatially and temporally distributed in the Biancavilla site, therefore the development and application of a Geographic Information Systems (GIS) was very useful to review, manage and analyze the obtained data and to give direction to the stakeholders in order to define the required remediation activities. A WebGIS was also developed to provide a rapid GIS access and data management by various control bodies.

Nowadays more and more applications require a mobile robot able to operate autonomously in an outdoor environment. The accuracy and precision of mapping systems for the working environment is particularly important for the management, control and efficiency of the activity of the mobile robot. For these reasons, mapping systems must be consistent and efficient, and capable to represent in real-time the surroundings, thus allowing the robot, equipped with a system of autonomous movement, the exploration of unknown environments. Here we present a new Web GIS platform able to track the navigation of mobile robots on a georeferenced cartographic data and to assign possible paths or waypoints. The WebGIS platform has been developed using only free and open source software and has been customized with useful tools for the management of the navigation of mobile robots.

The theme of the simulation of hydrogeological risk with GIS technology is analyzed with focus on the modeling of the architecture of a Spatial Data Base to support risk analysis and on the construction of a specialized frame with free and open source software. For this purpose a model of analysis of the vulnerability of roads developed by (Cafiso et al., 2002) has been adopted. The case of study is represented by a seismic land characterized by steep slopes and frequent instability phenomena. In detail, the area of interest is a mountainous land in Sicily with a city, Enna (about 30 000 people), that lies on the top. The access to the city is assured by few and very winding roads which are also highly vulnerable to seismic and hydrogeological hazards. The loss of efficiency of these roads for exceptional rainfall events should compromise timeliness and effectiveness of rescue operations. The data of the sample area have been implemented in the specialized GIS appositely constructed in order to forecast the possible damage to roads and the results of some simulations have been related to the effects registered after some extreme events, obtaining useful indications for the validation of the approach.

Unmanned Ground Vehicles can be a useful tool to help operators in humanitarian demining. However in many difficult environments autonomous operations are impossible and moreover it can be really difficult to teleoperate the robot from an onboard camera. This work presents an architecture to allow cooperation between a ground robot and a quadrotor UAV. The UAV can autonomously follow the ground robot, by using an image processing algorithm. In this way aerial images are provided that can help trajectory planning in rough environments, via a developed webGIS platform.

The autonomous navigation of a robot can be accomplished through the assignment of a sequence of waypoints previously identified in the territory to be explored. In general, the starting point is a vector graph of the network consisting of possible paths. The vector graph can be directly available in the case of actual road networks, or it can be modeled, i.e. on the basis of cartographic supports or, even better, of a digital terrain model (DTM). In this paper we present software procedures developed in Grass-GIS, PostGIS and QGIS environments to identify, model, and visualize a road graph and to extract and normalize sequence of waypoints which can be transferred to a robot for its autonomous navigation.