of air and road transportation. Beyond that, the major direct pres- sure from coastal tourism on the marine and coastal environment is the demand for space, both in the coastal zone, resulting mainly in urbanisation, and on the coastline itself, through construction of marinas and other infrastructure that leads to concretisation of the shores. The concentration of tourism within specific geograph- ical areas and limited time periods increases pressure on natural resources such as fresh water and leads to higher rates of sewage and solid waste production. Coastal tourism is, by definition, locat- ed in sensitive habitats within the coastal zone, such as beaches, sand dunes, and wetlands. The unavoidable result is change in the state of these habitats and their associated ecosystems, as well as economic impacts on other activities that benefit from coastal ecosystem services. Unsustainable development of mass tourism will result in the rapid degradation of fragile natural habitats (EEA and UNEP 1999, UNEP/MAP/MED POL 2005).
Marine transport Another strong traditional economic sector in the Mediterra- nean is transport, specifically maritime transport. The Mediter- ranean Sea is among the world’s busiest waterways, accounting for 15 % of global shipping activity by number of calls and 10 % by vessel deadweight tonnes (dwt). More than 325.000 voyages occur red in the Mediterranean Sea in 2007, representing a capa- city of 3.800 million tonnes. Almost two-thirds of the traffic was internal (Mediterranean to Mediterranean), one-quarter was semi-transit voyages of ships mainly of small size, while the re- mainder was transit voyages, mainly by large vessels travelling between non-Mediterranean ports through the Mediterranean’s various straits: the Straits of Gibraltar, the Straits of the Darda- nelles, and the Suez Canal (data provided by REMPEC).
During the last ten years, merchant vessels operating within and through the Mediterranean have been getting larger and carrying more trade in larger parcels. Vessels transiting the Mediterranean average 50.000 dwt and are, on average, more than three times
larger than those operating within the Mediterranean. Transit densities, measured in terms of ship voyages, are dominated by high-frequency, small-size intra-Mediterranean passenger traf- fic. However, the majority of trade, including petroleum oils and gases, is concentrated in larger vessels sailing less frequently (data provided by REMPEC).
The major axis, which sees 90 % of total oil traffic, is from east to west, connecting the eastern passages of the Straits of the Dar- danelles and the Suez Canal with the Straits of Gibraltar. This axis passes between Sicily and Malta and closely follows the coasts of Tunisia, Algeria and Morocco. Traffic branches off as it moves westward to unloading terminals in Greece, the northern Adri- atic, the Gulf of Genoa and near Marseilles. It is intersected by tanker routes connecting Algerian and Libyan loading terminals with the northern Mediterranean oil ports. From the eastern Mediterranean another important route links crude oil terminals in the Gulf of Iskenderun and on the Syrian coast with the main axis (EEA and UNEP 1999).
Passenger ships (34 % and concentrated in the western Medi- terranean) and dry cargo ships (31 %) make up the majority of ships calling at Mediterranean ports. Ships transiting through the Mediterranean without stops are dominated by dry cargo ships, which account for nearly two-thirds (61 %) of the voyages. Other transiting ships are container ships (13 %), tankers (chemi- cal tankers 8 %, product tankers 5 %, crude oil tankers 4 %), and passenger ships (4 %). Container ships and tanker ships, howev- er, represent an important part of the tonnage.
The Mediterranean is a major load and discharge centre for crude oil. Approximately 18 % of global seaborne crude oil ship- ments take place within or through the Mediterranean, even if only 2 % of the ship calls are crude oil tankers. The major traffic lanes are dominated by crude oil shipments from Novorossiysk (in the Black Sea) through the Straits of the Dardanelles to Medi- terranean destinations, as well as exports from the Persian Gulf