A typical "calanchi" landscape on the Eastern Apennine margin (Atri, Central Italy): geomorphological features and evolution

The surroundings of the town of Atri (Abruzzo Region, Central Italy), situa ted about 10 km from the Adriatic shoreline, can be considered as represent ative of most part of the Italian seaward peninsular landscape. The subject of this research, the calanchi landscape, often generally considered as "b adlands" by non-Italian authors, is, in fact, made up of many singular land forms, each of which (calanco) corresponds to a more or less extended hydro graphic unit, The dynamics are mainly the result of the action of the parti cularly aggressive climatic factors (such as the Mediterranean rainfall reg ime) on weak substrata (clay, silt and sand of the Plio-Pleistocene marine cycles). The morphogenetic activity is: not only limited to channel erosion , but it is also due to repeated superficial slides, so that it should in f act be better to consider the calanco as the result of a "combined erosion" process (sensu [Zachar, D., 1982. Soil Erosion. Elsevier, Amsterdam]). Sin ce the mechanism regulating this process remains unclear, this work wants t o offer a contribution to this research field. Multitemporal geomorphologic al analysis has helped us to distinguish the different areas in which the c alanchi evolution has been more or less important in the past. In such a wa y, it has been possible to characterize the landscape evolution as a functi on of the parameters that influence soil loss, especially in areas, such as that of Atri, where calanchi-like landforms are highly developed. Moreover , this analysis, coupled with the processing of 40 years rainfall data, als o taking into account the concurrent land use changes, has clearly shown th at the areas affected by calanchi erosion on the Eastern Apennine margin, s till tectonically active, are progressively diminishing. (C) 2000 Elsevier Science B.V. All rights reserved.