Paolo Zatelli

A GIS decision support system for regional forest management to assess biomass availability for renewable energy production

Currently, the use of a mix of renewable and traditional energy sources is deemed to help in solving increasing energy demands and environmental issues, thus making it particularly important to assess the availability of renewable energy sources. In a heavily forested region, such as the Italian Alps, one of the main renewable energy sources is woody biomass. A reliable evaluation of biomass availability must take into account the local management of forest resources and the ability to reach forest areas, which is related to existing road networks, and the characteristics and morphology of the terrain. We have developed a new methodology to estimate forest biomass availability for energy production in the Alpine area and to support management decisions, combining the morphological features of the mountain landscape with the current capabilities of forest technology. The approach has been implemented in a tool for forest biomass evaluation based on the Free and Open Source Software for Geospatial (FOSS4G) framework and to refine the current estimates made by the local government. The methodology was tested on the forests of Trentino province (Italy), providing an accurate evaluation of biomass availability, which can be effectively used to identify possible locations for biomass power plants and to suggest new forest management guidelines. The methodology, combining GRASS, PostgreSQL and PostGIS, can be applied to a wide area and can also be executed as a new GRASS module. Being open source it is already available for testing and development.

Development and Application of 2D and 3D GRASS Modules for Simulation of Thermally Driven Slope Winds

The ability to manage and process fully three-dimensional information has only recently been made available for a few Geographical Information Systems (GIS). An example of integrated and complementary use of 2D and 3D GRASS modules for the evaluation and representation of thermally induced slope winds over complex terrain is presented. The analytic solution provided by Prandtl (1942) to evaluate wind velocity and (potential) temperature anomaly induced by either diurnal heating or nocturnal cooling on a constant angle slope is adopted to evaluate wind and temperature profiles at any point over both idealised and real complex terrain. As these quantities depend on the slope angle of the ground and on the distance from the slope surface suitable procedures are introduced to determine the coordinate n of a point in the 3D volume measured along the direction locally normal to the terrain surface. A new GRASS module has been developed to evaluate this quantity and to generate a 3D raster file where each cell is assigned the value of the cell on the surface belonging to the normal vector. The application of the algorithm implemented in

Landscape changes, traditional ecological knowledge and future scenarios in the Alps: A holistic ecological approach.

In recent decades, a dramatic landscape change has occurred in the European alpine region: open areas have been naturally recolonized by forests as traditional agricultural and forest activities were reduced and reorganized. Land use changes (LUC) are generally measured through GIS and photo interpretation techniques, but despite many studies focused on this phenomenon and its effects on biodiversity and on the environment in general, there is a lack of information about the transformation of the human-environment connection. The study of Traditional Ecological Knowledge (TEK), such as the ability to recognize wild plants used as medicine or food, can suggest how this connection evolved through time and generations. This work investigates the relationship between the natural forest cover expansion that influences the loss of open areas and the loss of TEK. Different data sources and approaches were used to address the topic in all its complexity: a mix of questionnaire investigations, historical maps, GIS techniques and modelling were used to analyse past land use changes and predict future scenarios. The study area, Trentino, Italy, is paradigmatic of the alpine situation, and the land use change in the region is well documented by different studies, which were reviewed and compared in this paper. Our findings suggest that open area loss can be used as a good proxy to highlight the present state and to produce future scenarios of Traditional Ecological Knowledge. This could increase awareness of the loss of TEK in other Alpine regions, where data on TEK are lacking, but where environmental trends are comparable.

Field measurements in river embankments: validation and management with spatial database and webGIS

This study focuses on the development of a system with a spatial database and a webGIS able to store, validate and display the data to assist the decision makers in managing early warning systems for river embankment failure. In order to obtain precise results, it is essential to have a tool with ability of managing a large number of data for checking their reliability and for locating them in the space. In this paper, special emphasis was given in the development of procedures to assess the reliability of the measures. For this purpose, the database includes all the information needed to describe the instrument performance, such as the sand pack size and casing diameter of open-standpipe piezometers for evaluating their time lag, and the calibration curves of transducers with the possibility of their updating. The position of the non-functioning instruments is identified through the analysis of the electrical signal and spatial displays, while the analyses of the redundancy and coherence of measures is used for detecting doubtful data. Database and webGIS were applied to the monitoring data of an embankment of the Adige River in Northern Italy. The database and webGIS system has proved to be a suitable and effective tool for the management and validation of real-time data and periodical field measurements.

A Practical Quality Index for the Applied Helmert Transformation

AbstractThe Helmert transformation is used in different procedures in geodesy, photogrammetry, and in general in geomatics. The assessment of the accuracy of the transformation, and in particular of the transformed coordinates, is often critical. In this paper, a new overall quality index describing the accuracy of the transformed points is proposed. This index was derived from the spectral radius of the variance-covariance matrix of the transformed coordinates by writing an expression that represents an upper bound of this quantity. The proposed index is fast to compute and expresses the extent of the uncertainty propagation in a clear and synthetic way. The paper presents the rationale behind the choice of the index and the algebraic steps for its computation. Finally, two examples, one using synthetic data and one involving the coregistration of a point cloud acquired with a laser scanner, are presented.

Geodetic Applications of Wavelets: Proposals and Simple Numerical Experiments

The aim of this paper is to treat at a review level some topics of the theory of wavelets that are relevant for some geodetic applications, to further specify some proposals already formulated by one of the authors (1994) and to enforce the proposals by mean of some numerical experiments. The papers about the geodetic applications of wavelets are quite numerous nowadays (see e.g. Barthelmes at al. 1994 and Ballani 1994), therefore it is worthwhile to better specify our present field of interest. Several authors developed efficient numerical algorithms based on the wavelet representation for the computation of linear operators in L 2 (Beylkin et al. 1991, Beylkin 1992, Alpert 1993). The application of these techniques for the computation of linear operators in physical geodesy is investigated in this paper. We only consider operators in planar approximation in order to rely on well established mathematical tools.