TERRITORIAL VULNERABILITY EVALUATION IN TIBER WATERSHED

By now it has become a widespread consistent practice in the European Union to consider very carefully and to regard as fundamental the basi c needs of man, such as health and safety, in relation to all producti ve activities which may be regarded as a possible source of environmen tal deterioration. At the national legislative level, factors and elem ents regarding the environment (water, atmosphere, soil, subsoil, land scape, etc.) have been pointed out which require the state of quality to be characterised and vulnerability to the pressures caused by man's activities to be evaluated. This has brought about an evolution in th e concept itself of environmental quality, which is understood more an d more as actual satisfying of man's needs through the proper use of r esources and the maintaining of an environmental equilibrium. Environm ental quality can be pursued therefore, by studying the most appropria te usage of the territory and by considering quality no longer as a hi ndrance, rule or Imposition, but as a goal shared by all in improving the quality of life. In this study a few instruments are proposed for evaluating the overall capacity of a given environmental element or gr oup of elements to withstand deterioration caused by outside pressure, which in this specific case is pollution from farming and livestock w aste and sewage. Territorial vulnerability can thus be evaluated throu gh a decision support tool (fuzzy logic), which allows different categ ories of people (researchers, politicians, planning technicians, citiz ens, etc.) to be involved in the evaluation process. For this study, t he vulnerability evaluation was applied to a complex, homogenous terri torial system, the Tiber watershed where there are environmental resou rces which are particularly sensitive, owing both to their intrinsic c haracteristics as well as to the pressures stemming from livestock pro duction activities, which is one of the major pollution risks along th e regional drainage pattern. The use of GIS software has allowed the m ethod of analysis and prioritising to be applied to environmental fact ors (weighting) as well as the rapid management of initial territorial data, also of differing types (qualitative and quantitative). The res ulting product is a vulnerability map where the territory is classifie d on the basis of the evaluations of the degree of response to stresse s induced by the livestock production activities.