In Tunisia, Garaet is a typical term for a large permanent body of water. An example for this is Garaet El Ichkeul, a large shallow brackish lake formerly famous for its water birds. It is surrounded by productive agriculture and major disturbances of its hydrological system occurred during the twentieth century. Following canalization, hydrological modifications were made to the five main inflowing rivers and all but one of these inflows has been dammed since 1984. Consequently, freshwater drainage inputs are now much reduced and the once extensive marginal Phragmites beds have greatly diminished. The lake bed is 1.5 m below sea level, which is the lake depth in summer. In winter, lake level increases are now attenuated and the former marsh zone is only partly inundated. In the past, water usually flowed out from the lake to the sea, but now seawater tends to inflow during dry periods. Since 1986, sluice gates on the Tinja River outflow have control over seawa-ter inflow, but there are conflicts between fisheries and biodiversity interests. In recent years, the salinity of Ichkeul has increased so that hypersalinity persisted in the mid-1990s. The Ichkeul lake was listed as a Ramsar site in 1971, designated a Biosphere Reserve in 1977, and an International Park in 1980. (The Convention on Wetlands, signed in Ramsar, Iran, in 1971, is an intergovernmental treaty, which provides the framework for national action and international cooperation for the conservation and wise use of wetlands and their resources.) The marshland and the lake used to receive some 200 000 overwintering and migratory birds annually, mainly ducks, coots, grebes cormorants, spoonbills, storks, herons, and waders; especially, the geese which declined in the 1990s, mainly because of the loss of marshland.

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