Physical Processes and Human Activities in the Evolution of the Po Delta, Italy

The Po delta covers a surface of about 1300 km 2 of reclaimed lands, fresh- and salt-water lagoons, low sedimentary shores and emerging sandy banks. Its evolution has been extremely complex and several historical deltas have been recognized. Up to the end of the Middle Ages, the coastal morphology of ancient cuspidate deltas appears to have been shaped basically by natural processes. On the contrary, the formation of the modern lobate delta has been largely the result of human intervention. The Po delta is one of the largest in the Mediterranean. It contains areas of great natural beauty and monuments of historical interest and has been recognized as an internationally important wetland. In order to improve the habitability of the area and exploit its resources, man has altered the fluvial sedimentation, controlled the river network, reclaimed marshy lands, and developed agriculture, fishing, tourism and industry. The concentration of population, settlements and economic interests along the Po delta has resulted in a drastic change in existing ecosystems, together with a general decrease in the standards of environmental quality, such as beach erosion, dune degradation, land subsidence and pollution. Today the greater part of the delta lies below sea level and, to prevent flooding, several defence structures protect the deltaic coastline. The complexity and the diversity of the problems that affect the delta clearly require a unified approach. Unfortunately, the management of the Po delta depends on numerous administrative competencies. This is one of the main obstacles to the full realization of the Po delta becoming a natural park.