CASTIGLIONI G. B.
Forme e depositi di origine eolica – Eolian forms and deposits
Pages 119-122
Abstract
According to the legend, the Geomorphological Map shows not only dunes (filled-in small violet circles) but also flattened dunes, generally reworked by anthropic action (empty circles). Overall, dunes do not occupy large areas in the Po Plain) except along the Adriatic coastline) where they are generally closely associated with littoral ridges. Here) although only a few metres high (rarely 10-11 m), they give) or once gave) morphological emphasis to the ridges themselves) being integral parts of them (Chapter 10). There are also «living dunes» in the back-shore zones) which may be found even to distances of 100-200 m from the shoreline (including forms covered with bushy vegetation). They are generally irregular in shape) partly defined as hummocky dunes, or are very small forms elongated preferentially according to the direction of the Bora toind, blowing NorthEast or East. Eolian morphogenesis is now hindered by coastal changes and the spread of anthropic structures. Beach retreat) clearly manifest in many stretches) has not only narrowed the belt subject to wind deflation) but has caused direct wave erosion of the old dunes and sometimes their total destruction (Bondesan, 1971). Many of these dunes of the coastal belt) which were subjected to extensive reafforestation programs in the first part of the 20th century) were later sacrificed to build tourist resorts: evident examples may be found in the Veneto-Friuli and Emilia-Romagna sectors. The need to acquire soil for horticulture) e.g.) in the area of Sottomarina (near Cbioggia), also contributed to dune flattening. According to a study on the Emilia-Romagna littoral (Cencini, 1991)) between 1955 and 1980 living dunes underwent an areal reduction from 370 to 105 hectares, and those already reafforestedfrom 570 to 315 ha. …