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Khor Al-Adaid natural reserve

Date of Submission: 18/03/2008
Criteria: (vii)(viii)
Category: Natural
Submitted by:
Supreme Council for the Environment of Natural Reserves
State, Province or Region:
South East of Qatar
Coordinates: N24 42 50 E51 24 55
Ref.: 5317

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The Khor Al-Adaid area, also known regionally as the ‘Inland Sea', is located in the south-east of the State of Qatar. The area presents a remarkable landscape formed by a globally unique combination of geological and geomorphological features. These features themselves create a diverse scenery of exceptional, undeveloped natural beauty, in what remains predominantly a ‘wilderness area'. Each landscape unit on its own, notably the Arabian Gulf, large mobile dunes, the tidal embayment system, inland and coastal sabkha, recently discovered "salt hummocks", stony deserts, elevated mesas and rocky outcrops, as well as the transition between each of them, contribute to the unique character of Qatar's southern territory.

This intrinsic attractiveness, of a largely uninhabited area, is added to by the presence of a diverse native terrestrial flora and fauna alongside a varied and sensitive marine ecosystem. The flora present in the area is typical of those habitats represented and supports species and communities mostly widespread on the Arabian Peninsula, yet not occurring in the same combination in any other single locality. The fauna includes several species which are internationally rare and/or threatened, for example Dugong and Turtles, with populations of certain species of bird being of national and regional importance, e.g. long-distance migrant waterfowl winter, and regionally declining breeding species also resident, including Ospreys nesting on islets. Terrestrial areas continue to support Arabian Gazelles, while there are plans to reintroduce Arabian Oryx within the hinterland of Khor al-Adaid.

The Inland Sea is a large tidal embayment with a convoluted shoreline, about 15 kilometres from north to south and up to 12 kilometres from east to west. It is connected to the Arabian Gulf by a relatively narrow, deep channel, about 10 kilometres in length. There is no comparable lagoonal system of this type known elsewhere in the world. The diverse water quality and bottom substrates create an exceptional variety of aquatic and semi-aquatic habitats of considerable importance for some endangered marine species, particularly turtles and dugongs. Furthermore there are several valuable archaeological sites and a diversity of cultural heritage sites to be found in the area. The rocky desert of the Al-Adaid area clearly supported bedouins and their grazing stock. Pre-historical use of the small islands in the khor has also been revealed. Traditional farming and fishing settlements existed in the area, but this lifestyle is now virtually lost. Some grazing of camels still continues.

Justification of Outstanding Universal Value

The area presents a remarkable landscape and offers world-class scenic beauty in both the terrestrial and marine environments. The juxtaposition of large mobile dunes reaching the sea coast, where they spill into the sea, together with the large tidal embayment, in an arid tropical environment, has no known parallel in the Middle East or indeed elsewhere in the world. The terrestrial part comprises perfect barchans and parabolic dunes, cliff-edged rowdat, wadis, mesas, limestone outcrops and karstic landforms, sabkhat and islands in the embayment system itself. The development of these features is the result of both ancient and present-day geological and climatic processes. The area's attractiveness is added to by the presence of representative floral and faunal communities typical of such habitats on the Arabian Peninsula. The landscape of the marine portion of Khor Al-Adaid, which is represented by the succession of the narrow and deep channel to the large shallow northern basin, is of extraordinary natural beauty. There is no similar large lagoonal system in other countries of the Arabian Gulf. It also presents a range of sensitive habitats: coral communities, rocky substrate with fleshy algae, sandy bottom with seagrass meadows, mussel beds and algal mats.

The area is the scene of outstanding examples of significant on-going processes in the development of landforms. The sabkha flats, salt-crusted desert extending from the Khor up to Mesaieed is different from the classic sabkhas, which are composed of calcium carbonate and derived from the sea. That in the Khor Al-Adaid area has built eastward by quartz sand being delivered from dunes by the dominant north-northwest shamal winds. In turn more sand dunes traverse this flat surface into the sea and are thus continually prograding the sabkha in a seaward direction. Nowhere else in the world can this rapid process of sabkha formation be observed and studied. There is a finite source of sand, and it is ultimately foreseeable that all the available supplies will have reached the sea and the sabkha system will stop expanding. This is why this on-going process is of considerable importance. The pisolites found in the area - coated shells with calcium carbonate precipitation - are the only ones known to exist in a matrix of quartz sand. In addition, the hyper-saline ground waters in the more landward parts of this sabkha contain very young primary dolomite crystals. Dolomite is common in ancient limestones, but this is one of the few areas in the world where it is presently actively precipitating beneath the surface around quartz sand. This sabkha is therefore a unique place for field studies of the chemical processes that form this mineral, which remains one of the largely unsolved mysteries of modern geology. In addition, the area comprises a large number of recently discovered "salt hummocks". Each of these hummocks or mounds is covered by a salt and gypsum crust, which may represent a former sabkha surface, corresponding with a former sea level. In this case it would be a strong indication of post-Pleistocene to late Holocene sea level fluctuations. Raised beaches here also attest to this phenomenon. Lastly, the area is the scene of progressive filling-in of the lagoon, as can be inferred from satellite images. Tidal currents keep it open near the entrance today, but if the shallow marine areas farther inland are filled, tidal currents would diminish and the rest of the inland sea might accrete entirely. Examining the satellite images in the vicinity of Umm Said (Mesaieed) shows an area that may, in the past, have been similar to Khor Al-Adaid. The Khor Al-Adaid area provides an instructive outdoor classroom for presently active geological and geomorphological processes, which, indeed, already attract national and international visitors, including both ‘sight-seeing' tourists and academics.

Although qualifying for World Heritage Status on the two criteria described above, the area also demonstrates significant, unique, ongoing ecological and biological processes in the evolution and development of terrestrial, coastal and marine ecosystems and their respective communities of plants and animals, which represents a third qualifying criterion by which nominated sites are judged for acceptance onto the World Heritage List.

Statements of authenticity and/or integrity

In general, the integrity of the property is demonstrated by the fact, that it includes all the elements of outstanding universal value of the area. Moreover, these are either mostly pristine or otherwise relatively undisturbed. The property is mostly uninhabited and the borderland in the south is remote and rarely visited. All areas essential for maintaining the beauty of the property are included in the property. The nominated area includes most of the mobile dune area, while the entire marine ecosystem is included in the area. Terrestrial habitats, other than sand dunes, include the stony hinterland which contains flora and fauna communities typical of the Arabian Peninsula. Also, the diversity of aquatic and semi-aquatic habitats demonstrates that the ecosystem remains healthy. The size of the property is sufficient for the ongoing functioning of the natural biological system to remain viable and for geological and geomorphological processes to operate undiminished. 

Comparison with other similar properties

There is no similar assemblage of terrestrial and marine environments, with a large tidal embayment lying within an area of mobile dunes, and of sabkhat systems, anywhere else in the world. This assemblage depends on the significant continuation of ongoing processes in the development of landforms. These geological and geomorphological processes cannot be observed and studied in this juxtaposition elsewhere in the world. The interaction of processes and the appearance of sabkha ecosystems and salt hummocks were identified by international interdisciplinary experts as an area of global importance (Barth et al. 2005).

The varied ecosystem of Khor Al-Adaid is of international scientific interest and shows remarkable adaptations to the extreme environmental conditions: limited rainfall, very high seawater temperatures in summer (up to and occasionally more than 33°C.), very low sea temperatures in winter and high salinity. The location of Khor Al-Adaid coral communities is predicted by Sheppard (2003) to have the greatest temperature range within the Arabian Gulf. Phillips (2003) adjudged the seagrass beds, extending from Bahrain down the East coast of Qatar and along the coast of the United Arab Emirates, as being one the most productive in the world and as important feeding grounds for endangered species including turtles and dugongs.

A nomination on the Natural World Heritage list would be the first one in the State of Qatar and the second on the Arabian Peninsula. The IUCN Advisory Body evaluated a nomination file for the Hawar archipelago, Kingdom of Bahrain, and called for the establishment of a coastal Natural World Heritage Site with neighbouring countries which have a shared responsibility for the islands and surrounding waters. 

The single natural World Heritage Site currently in the Arabian Peninsula is the (Arabian) Oryx Sanctuary, Jiddat al-Harasis/Yalooni, in the Sultanate of Oman. This site is landlocked in the interior of that country and is not ecologically comparable with Khor al-Adaid, Qatar. It was established on account of supporting the only free-living herd of Arabian Oryx within the species' original natural range, and on the presence of representative communities of flora and fauna characteristic of the country's extensive central desert. Having stated this, the possibility of reintroduction of Arabian Oryx to the Khor al-Adaid area, where they once occurred naturally, is currently under investigation.