Agricultural irrigation and population growth are also reducing the flow of fresh water in the rivers that feed the Mediterrane- an’s alluvial plains. In most Mediterranean countries with an er- ratic rainfall pattern, many of the available sources of water have already been developed or are currently being developed. Esti- mates by Blue Plan conclude that by the year 2025, eight of the twelve southern and eastern Mediterranean countries could be consuming more than the total of their renewable water sourc- es (UNEP/MAP/MED POL 2005). Already, all major rivers flowing into the Mediterranean have had much of their flows diverted to agriculture and other uses over the past 40 years, resulting in a 20 % reduction in freshwater inflow into the Mediterranean (Ludwig et al. 2009).
Soil and freshwater Around the Mediterranean Sea, alluvial and coastal plains are few and not extensive, the Nile Delta being by far the largest. The coast- al lowlands are particularly vulnerable to climate change, which can affect hydrology, sea levels and ecosystems. They are also threat- ened by the results of human activity, such as pollution and sedi- ment flow from intensive agriculture and industrial development, both local and upstream. The intensification of agriculture, in par- ticular, has reinforced a long-term trend toward desertification in the region. About half of Mediterranean lands are subject to the risk of erosion (UNEP/MAP/MED POL 2005) and therefore of soil loss.
Oil and gas The oil industry is extremely active in the Mediterranean Basin, with Libya, Algeria and Egypt considered moderate-sized petro- leum producers and refineries distributed all around the basin. In some countries, such as Greece, Italy, Cyprus, Israel, Lebanon and Turkey, domestic oil and gas production is relatively small, but exploration is very active especially since the recent vast discoveries and assessment of undiscovered reserves in the Le- vantine Basin Province in the eastern Mediterranean (EEA and UNEP 1999, Schenk et al. 2010). Complex geology and large, un- explored regions contribute to the uncertainty in determining the size of hydrocarbon resources in the Mediterranean region. The total known oil reserves are estimated at more than 45.000 million barrels. Exploration is the focus of most companies oper- ating in the area and the most attractive exploration regions are located in both onshore and offshore areas.
Among the better prospects are four in Algeria (at Ghadamis and Illizi basins near the Algeria-Tunisia-Libyan borders), three in Libya (at Sirte, Ghadamis and Murzuq basins), six in Egypt (at Ashrafi in the Gulf of Suez, East Tanka offshore, Western Desert, Meleiha, Qarum and Abu Gharadiq), four in Greece (north-west Peloponnesus, Ioannina, Aitoloakrnania and the Gulf of Patraikos