TECNICHE DI RILEVAMENTO PER LA PREVENZIONE DEI RISCHI AMBIENTALI

Surface monitoring is essential to understand the spatial and temporal evolution of complex landscape modifications and instabilities related to road and railway infrastructures. In recent years, the terrain change detection methods have evolved particularly with the development of increasingly automatic extraction procedures of both DTM and DSM. Prevention of damages caused by natural disasters does not only concern weather forecasts, but requires constant attention and practice of monitoring and controlling human activity on territory. Practically, the problem is not knowing if and when an event will affect a determined area, but recognizing the possible damages if this event happened, by adopting adequate measures to keep them down as far as possible, and requires the necessary tools for a timely intervention. To solve such requirements, current satellite technology, with recurrent data acquisition for the timely generation of cartographic products updated and coherent to the territorial investigation, offers the possibility to fill the temporal gap between the need of urgent information and official reference information. The fundamental merits of the high resolution remote sensing methods are the ability to perform surveys at regular intervals, the characteristics of the image and the revisit times. These features are very useful in environmental monitoring especially in the event of emergency or also in medium scale cartographic production, particularly in the zones of difficult access and in developing countries. The research presented here aims at answer to the growing need of optimization and rationalization of long term monitoring systems of displacements and degradation due to the interaction of artificial artifacts of transport with such natural phenomena. To test the methodology we chose an area that presents a particular geo-morphological setting, in the municipality of Fasano (BR, Southern Italy). The area is affected by frequent hydrogeological dangerous events such as flooding and is classified as a zone of “high hydraulic hazard” in the regional Hydrogeological Structure Plan (PAI). For this area we used a GeoEye-1 stereo-pair for extracting a DTM in order to verify the usefulness of satellite techniques for the recognition of environmental risks.