MONITORING CHANGING LANDSCAPES: IMPROVING KNOWLEDGE OF SPATIAL RESOURCES

As it is well known, for a long time economic and land use management policies paid poor or inadequate attention to the study of landscape considered as a complex system. However, in the last decades various landscape topics have been arousing growing interest. Thus several critical issues have been pointed out and some well-established and shared considerations have been outlined, on which both scholars in various fields and legislation policies agree. The greater attention to the need for a renewed management of landscape transformations has also been driven by recent regulations and various documents and activities by several international organizations (such as UNESCO, ICOMOS, Council of Europe and European Union). It is acknowledged that the European Landscape Convention (Florence, 2000) and its conceptual and practical outcomes proved fundamental in such process. It is worth mentioning the well-known and shared principle that landscape is not a simple aggregate of natural and artificial features, and that it has to be analyzed through a systemic approach, capable of considering it as an articulated complex of systems made up of manifold elements and relations (spatial, functional, ecological-environmental, visual, symbolic), which followed one another intertwined over the centuries on the same territory. Moreover, landscape resources are considered a heritage to be characterized and assessed not only from an economic or ecological point of view, but also in terms of cultural identity. The appropriate management (protection, restoration, enhancement) of such heritage requires broad and deep knowledge. Each spatial system, meant as a landscape resource, must thus be read and characterized in detail by analysing its various features in order to interpret it within the entirety of the systems and relations that create the landscape. This paper proposes a methodological contribution aimed at developing improved-efficiency techniques for analysing the various natural and anthropic landscape resources, through a systematic and interdisciplinary approach. First of all, a critical analysis of the scientific literature is reported, focusing on the techniques available for the study of landscape characters and their changes based on complex and multivariable geographic data, also referring to areal sampling methods. Then, based on this critical review, we further developed a technique for the multi-time inventory of landscape resources. This system, aimed at assessing the changes in the various landscape systems, is based on the definition of suitable representative sample areas and their cartographic and photographic GIS survey. The methodology consists in the development of an inferential statistical technique which allowed us to define a stratified random sampling design, according to the following main steps: construction of appropriate sampling frames by means of spatial discretization; stratification of the resulting areal units according to ad-hoc variables and criteria; definition of parameters suitable to assess the structure and evolution of the various resources of the landscape systems.