In order to the environmental characteristics one significance product that it is possible
to show is the “biopermeability” map based on physiographic units.
Biopermeability condition is related to the territories that are not interested by urbanisation
phenomena, comprised some very intensive agricultural forms (Romano 2000).
The key information to read biopermeability at the territorial scale is the land-use map and
particularly suitable is the “Corine Land Cover” that has also some information on vegetational
characteristics (Commission of the European Communities 1991).
Corine Land Cover categories (Level 3) linked to the biopermeability condition:
Land principally occupied by agriculture, with significant areas of natural vegetation;
Broad-leaved forest;
Coniferous forest;
Mixed forest;
Natural grasslands;
Moors and heathland;
Sclerophyllous vegetation;
Transitional woodland-scrub;
Bare rocks;
Burnt areas;
Glaciers and permanent snow;
Inland marshes;
Coastal lagoons;
Salt marshes;
Water courses;
Water bodies.
The situation in areas of intensified or specialised farming on the other hand is completely
different.
The presence of buildings, even if isolated, means movement of people, night lighting and
noises. Barriers delimiting property borders are solider and more difficult to cross (wooden or
metallic fencing, stone walls) but even without these barriers, the daily activity of man creates a
continuous disturbance. The road network, even in these rural areas, is always dense and
widespread. The level of bio permeability in this type of area was considered too low to be
inserted into ecological corridors.
These conclusions are confirmed by the Map of Natural Habitat which uses the Corine Biotopes
Manual (CEC 1991) classification and considers meadows and grazing lands the minimum
natural level.