Terraced landscape, GIS and the relations between the hinterland and the coastline. 5 Terre: a case study in the ALPTER project.

Gerardo Brancucci, Guido Paliaga

POLIS Department, Faculty of Architecture
University of Genova (IT)

Along the past centuries man has induced deep changes in the landscape of wide areas with the aim to obtain terrain suitable to farming. This modification has been done varying the profile of the terrain to gain sub horizontal surfaces and managing the flow of the rainfall runoff. Depending from different parameters like the original slope, the lithology, the soil type and others, different kind of techniques have been applied: some of them make use of series of little stone wall alternated to horizontal surfaces and some other simply use soil and vegetation to produce the same effect.
The process of changing the slope of the surface, the flow of the rainfall runoff and of immobilising soil is, from a geomorphologic point of view, an interference with the geomorphic system who guides the dynamics of the earth's changing surface. Actually the abandonment of terraced agricultural areas results in a new interference with the geomorphic system: the lack of maintenance of a man altered landscape implies the geomorphic system to gain the control back by means of erosion processes. The final result is the increase of the geomorphologic hazard with diffuse problems of instability and the raise of the solid transport in the rivers.
In areas like the Liguria territory this problem assumes a particular importance because of the strong and direct linkage between the hinterland and the coastline where most of the human activities are concentrated. This strong linkage is determined by the peculiar morphology and climatic situation of the region that has some similar ones in the Mediterranean basin.
The Interreg project Alpter was born to contrast the abandonment of terraced agricultural areas in the alpine region, a problem that only during the last years has risen the attention of both institutions and population. Loss of productive land, increase of natural hazard, loss of biodiversity and disappearance of a rich cultural heritage are all consequences of the decay of terraced structures.
The project will work in areas spread all over the alpine region, to collect data, develop specific technologies and realize examples of productive recovery. The final aim is to promote large scale transformation. At the same time, a network will be build, to put in contact the different subjects involved in this topic, to permit exchange of information and coperation.
One of the contribution to the project that the Laboratory of Applied Geomorphology is developing with the Regione Liguria Spatial and Landscape Planning Department is to develop a model to quickly and precisely monitor and survey the terraced territory with the aim of GIS technologies and to predict the geomorphic hazard.