The "SITRA" : methodological approach (part 1)

Premise

The analysis of the problems connected with the impact of the natural phenomena on the historical and natural patrimony, required a first phase of acquisition of data available nearby the local authorities and universities. Subsequently we passed to the definition of the technical criterions for the predisposition of a "container", able to contain, contemporarily, all the data that we find and to manage them in operation of different demands of use.

In this way the SITRA (acronym of Territorial Informative System for the Environmental Risks) was born.

The SITRA picks up and manages all the available data nearby the local authorities according to a rigid protocol of acquisition.

One record of a specific database is associated with every datum, or data set ; this record describes deepen the content, the generator, the user, etc., according to defined criterions of representation.

Subsequently, according to a procedure of conversion certified by an agency, we proceed to the translation of the datum or data set in a international system of reference and not in local systems of reference.

In the actual phase of the job, within the CARTODATA subproject, we have to complete SITRA’s while METADATA compilation has been finished. In the next and last phase we are going to debug the procedures for the certified conversion of the cartographic data.

The territorial context of reference

Molise is a small Italian region (around 4400 km2) situated in center-southern Italy among the Apennines and Adriatic Sea.

The particular position of Molise in the geologic context of the Mediterranean area and its recent structural evolution are the natural factors that have determined the actual geomorphological scenery and that define the hazard of some natural phenomena potentially catastrophic.

In Molise coexist an elevated seismic hazard, due to the recent evolution of the central Apennines, and an elevated hydrogeological hazard, structurally connected with the presence of geologic complex formations and of very clayey soils. The presence of important rivers with Adriatic delivery and of often accelerated slope evolution, to them connected, contributes to make of this small Italian region one "gym" for the study of the natural hazards.

Moreover the presence of numerous water bodies of strategic importance not only for the drinkable and irrigated use of the region Molise, but also for that of the neighbouring regions Campania and Puglia. The guardianship of the water resource and the vulnerability of the water bodies, often situated in proximity of sources of potential pollution, is a further element of attention in a suit picture of knowledge regarding the natural and environmental risks.

If we think that the historical, architectural and environmental heritage must be protected towards the natural calamities, we understand as a correct management of the territory passes through a series of political-administrative actions that improves the conditions of knowledge of the hazard from a side and from the other one reduces the vulnerability of the exposed good.

The limit among calamity produced by natural agents and calamity produced by the human activity is often few clear. The calamities of the first type include volcanic eruptions, earthquakes, floods, instabilities of the slopes, cyclones and storms, etc. ; the calamities of the second type include the phenomena connected to the indiscriminate deforestation, with the introduction of harmful gas into the atmosphere, with the incorrect use of the territory, with the unconditional exploitation of the water resources, with the industrial activities with introduction of pollutants in the different geochemical spheres. In Molise are very important the risks connected to natural phenomena what the seismic activity, the evolution of the slopes, the flood of rivers and the withdrawal of the line-coast (Adriatic) ; as it regards the connected risks with the human activity there are the chemical risk (in the areas where are present chemical factories) and the risk of pollution of the water resource.

Both the risks are managing through a rich and homogeneous base of knowledge on the regional territory ; one of the principal objectives of the scientific community is to furnish the correct support of knowledge for the following activities of respect of the attended damage and the possible sceneries of risk.

The necessecity of implementation of a sit

The knowledge of the dynamics of the risk, whatever it is, therefore, part from the analysis of the spatial distribution of all the factors that compete to its configuration. The knowledge of the hazards and of the actual use of the territory also allows very inclined analysis and the configuration of sceneries of risk on which to activate all the necessary actions (political-administrative) for the mitigation of the attended damage.

The management of a territory is born really from the awareness that the realization of a respectful territorial politics of the context within it is thought and that the sustainable development of a region also passes through the knowledge of the possible consequential damages from the catastrophes and of the dynamics that potentially determine them.

The situations of risk can be mitigated through actions oriented to the reduction of the natural hazard (or human), to the reduction of the vulnerability of the exposed elements or both.

Only through the knowledge is possible to start concrete actions of territorial planning that have, as substratum, the data of distribution of the different phenomena and the removal of the most important activities. Among these the most important are really the architectural-cultural heritage because the elements cannot be moved and, therefore, they have to been protected towards the incumbent calamity.

The contemporary management of deeply different layers among them for presuppositions and contents is very complex. Their management in the same geographical space, however, allows not otherwise overlaps and cross analysis possible with analytical criterions disconnected by the topographical base.

From some years numerous tools software (the GIS) are available and allow to contemporarily manage punctual, linear or polygonal objects in geographic system and to associate to every of them one or more alphanumeric data.

Also in Molise, as in other regional realities, some initiatives are been activated turned to obtain the wedges of a more articulated Regional Territorial Informative System. The possibilities of development and expansion of the system, are nearly obviously boundless, because is possible always to add information to the System and make it richer and powerful.

One of the problems of greater relief in the data management concerns its reliability (in geographical sense and of content) and the so-called ability to be validated from a third organism. The validation represents one of the most complex phases in the management of a SIT because an error in such phase determines the use of few reliable data and incorrect elaborations.

For these reasons there is the necessity, for the activities of competence of the University of Molise that essentially concern the problem list of hazard and vulnerability of the natural resources, to realize a system of validation that introduces data, inside the Informative System, those is possible a real respect of reliability and a trace of the data.

The trace of the data is possible equipping, every data set, of additional information (metadata) that define, time for time, its typology ; the respect of the reliability of the data derives from an expert judgment expressed through a cross control with existing databases or through the direct knowledge of the problem list and the phenomena.

The SITRA : Territorial Informative System for the Environmental Risks

The fundamental activity for mapping of the territorial context of reference is turned to the harvest and the management of necessary numerous series of territorial data for the analysis of the specific problem list of the district of reference and for a correct use of the resources.

The fittest tool for such purpose is represented by a GIS (Geographic Information System). It is a software able to manage, contemporarily, several informative layers of different nature (vectorial and raster) characterized by an univocal spatial position in geographical coordinates which are connected alphanumeric data (descriptive) or raster (images, cartographies, etc.). The database will be realized by Access, a Microsoft software, perfectly interactive in ESRI environment.

For mapping of natural risks we held to use the release 9.1 of the software ArcView GIS, produced by the ESRI Inc.®. Subsequently, as arranged in the precedents technical meetings with the partners of the subproject, we shall proceed to the conversion of all the data in formed compatible with the release 3.x of the software ArcView produced by the ESRI Inc.®, in how much currently more diffused in comparison to the following releases to level of Public Administration, with which University interacts in coordinated form.

The Territorial Informative System for the Environmental Risks (SITRA) will manage the geographical information related to the dangerousness and to the building, architectural and historical-cultural, as well as environmental patrimony, whose criterions of validation and respect of the reliability are known and perfectly repeatable too.

Such factor constitutes the element of strength of the whole trial ; in this way is possible add to a "known" data base (or for which the metadata are available) progressively new information of note reliability.

The SITRA was born, therefore, with the methodological presupposition of the reliability, not in generic sense, but according to the exposed first meaning.

In the SITRA all available data sets nearby local authorities will put in, after a complex job of validation and respect of reliability. Such data sets are contains basic information (not concerning hazard or vulnerability but only the elements that compete to define them) and to elaborate information (or consequential from experienced respects and from numerical trials).

Informative layers of base

The basic element of the SITRA is represented by cartography that, necessarily must be adjourned, adjournable and, preferably, in numerical form.

The SIT has to be enriched by thematic cartographies that come following proposed.
 Use of the ground (sour-forest ground with outlines of the natural and artificial wooded areas, of the areas turned to specialized crops - vineyards, olive-groves and orchards and of those turned to extensive uses ; continuous and discontinuous urban fabric)
 Geology, geomorphology and hydrogeology (compiled on bibliography integrated “in the field”)
 Net services (government, provincial and town roads, railroads, aqueducts, methane piping, power lines, footsteps fireproof, paths)
 Infrastructures of public utility (barracks, hospitals and clinics, schools, places of cult, town and territorial offices)
 Architectural and cultural emergencies (monuments and buildings of architectural and/or historical value, museums, archaeological excavations, libraries, art gallery, etc.)
 Environmental emergencies
 Productive activity (industries and workshops, artisan firms, firms of production in the sector to sour-feed, fittings for the extraction and the workmanship of rocks)
 Works for use of underground water resources (drinkable, agricultural and industrial purpose).

Informative layers of job

The informative layers will be elaborated within the project concern the components more interesting retentions, to the actual state, to the articulated SIT regarding the natural and environmental risks.

The components inserted in the study are, essentially, the ground and the water, firm the possibility of future integration of the system staying with other components, also of human origin.

For the specific informative layers we have produced the followings :
 Seismic hazard map (based on all the available elements nearby the public structures that to the study and control the territory : Town Council, Provinces, Region, University, Corporate body of search)
 Landslide hazard map (based on all the available elements nearby the structures preceded to the study and the control of the territory : Town Council, Provinces, Region, University, Corporate body of search)
 Flood hazard map (based on all the available elements nearby the structures preceded to the study and the control of the territory : Town Council, Provinces, Region, University, Corporate body of search)
 Pollution of the water strata hazard map map (based on all the available elements nearby the structures preceded to the study and the control of the territory : Town Council, Provinces, Region, University, Corporate body of search)
 Coastal erosion hazard map (based on the analysis of the trend of withdrawal of the coast in the last century). Such map has been produced by coordination between University of Molise and Group of Job ENEA that, currently, has been conducted searches on this thematic.

All the maps of the SITRA will be reported to the Datum Roma 40 (for the complete compatibility of data set with the Regional Informative System of Molise). Only the cartographies and the thematic bases will be converted, through rigorous procedures of calculation, also to the Datum WGS84, more currently used in national and international circle.

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