I catasti storici come strumento di prevenzione del rischio ambientale : Il catasto lombardo-veneto e la sua applicazione nell’area lariana

In XX Century, terraced landscapes suffered a general and widespread abandonment. The abandonment of these spaces represents an ever-present problem: in fact, anthropic intervention on sloping lands falsifies the environment original balances and when steady and ordinary maintenance come less, ground tends to restore starting situation. So, abandoned terraces involve a high hydrogeological instability; in the absence of a precise knowledge about location and density of the abandoned terraced areas, it implies a huge problem about prevention. Nowadays, in Italy, regional mapping of terraced areas is still rare and resents of many difficulties as the excessive cost and the complexity of the relief. A possible solution could be represented by historical Land Register, that analytically reported terraced surfaces both in the registers and often also into the cartographic representation, by parcelling of the proprieties. For example, at the second half of XIX Century, Lake Como had about 1,800 hectares of terraced surfaces that nowadays appear almost completely abandoned and unknown. The re-reading of these historical information enables both to mapping on the regional scale the historical extension and density of the phenomenon and to accurately locate the single terraced areas into each municipality.