Sandy coastal ecosystems and effects of disturbance in central Italy

This study describes the vegetation zonation of the coastal sandy landscapes of the Lazio region (Central Italy) and analyses the effects of disturbance (in the main human, but also natural) on this vegetation. A comparison is made between real and potential coastal vegetation using a hierarchical landscape classification approach, which identifies land units on the basis of a combination of climatic, lithological, geomorphological and hydrogeological factors, integrated with phytosociological data. Information about the coastal phytocoenoses was obtained both from previous studies and from original phytosociological data (241 releves). Observation of real vegetation showed that coastal zonation is relatively well-preserved at only a few sites along the Lazio coast. At these sites real vegetation distribution is very similar to the potential zonation. However, widespread disturbance means that real vegetation is drastically different from the hypothetical phyto-topo sequence along most of the coast. Where disturbance has been particularly intense or prolonged in time, coenoses have often completely disappeared. Where disturbance is severe, but slightly less so, coenoses tend to have became fragmented or substituted by replacement communities