Réghaïa lake is located in the commune of Réghaïa, Algeria, 29 km east of

Algiers Algiers is the capital city of Algeria as well as the capital of the Algiers Province; it extends over many Communes of Algeria, communes without having its own separate governing body. With 2,988,145 residents in 2008Census 14 April 2008: Offi ...

. It collects water from a watershed of 842 km², from which the Oued Réghaïa flows. The lake, together with the Réghaïa forest, was recognized as a

Ramsar site A Ramsar site is a wetland site designated to be of international importance under the Ramsar Convention,8 ha (O) *** Permanent 8 ha (P) *** Seasonal Intermittent < 8 ha(Ts) **

. It is located in the commune of Réghaïa in the

Mitidja Mitidja, (Arabic: ) is a plain stretching along the outskirts of Algiers in northern Algeria. It is about long, with a width of . Traditionally devoted largely to agriculture and serving as the breadbasket of Algiers, the area has in recent decad ...

region of Basse Kabylie.

Description

Réghaïa lake corresponds to the estuary of the Oued Réghaïa, whose mouth is blocked by a dune belt. Some 600 meters upstream from the

Mediterranean The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...

, an artificial dyke retains the permanent waters of the marshland site. This maritime marsh has gently sloping banks.

History

Before the 1930s, when the dunes held back the Oued Réghaïa and its bed had not been deepened, there was a natural marsh rich in waterfowl, but the quest for new farmland led to the wadi being drained by pumping, draining and planting eucalyptus trees. This project was eventually abandoned, and an earth embankment was built to create a reservoir for irrigation, followed by another embankment to hold back larger volumes of water from the wadi. The downstream channel was then recalibrated.

Physical characteristics

Geology

Réghaïa lake is characterized by a

Neogene The Neogene ( ,) is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period million years ago. It is the second period of th ...

syncline of fine

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

and Plio-

Quaternary The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS), as well as the current and most recent of the twelve periods of the ...

deposits located midway between

Gibraltar Gibraltar ( , ) is a British Overseas Territories, British Overseas Territory and British overseas cities, city located at the southern tip of the Iberian Peninsula, on the Bay of Gibraltar, near the exit of the Mediterranean Sea into the A ...

and the

Sicilian Channel The Strait of Sicily (also known as Sicilian Strait, Sicilian Channel, Channel of Sicily, Sicilian Narrows and Pantelleria Channel; or the ; or , ' or ') is the strait between Sicily and Tunisia. The strait is about wide and divides the Tyr ...

. This geological formation, which folded and then filled, is characterized by alluvial and marshy facies. Recent and current Quaternary facies are composed of marine and lacustrine deposits, recent pebbly and silty alluvium, consolidated

dunes A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat ...

scallop Scallop () is a common name that encompasses various species of marine bivalve molluscs in the taxonomic family Pectinidae, the scallops. However, the common name "scallop" is also sometimes applied to species in other closely related famili ...

lumachelles, marine poudingues and sandstones, clayey sand and ancient Quaternary alluvium.

Geomorphology

Réghaïa lake is located on an elevated central plateau in the Réghaïa region. Its surface, deeply incised by numerous torrential

valleys A valley is an elongated low area often running between hills or mountains and typically containing a river or stream running from one end to the other. Most valleys are formed by erosion of the land surface by rivers or streams over a ve ...

, has an undulating configuration criss-crossed by the Oued Réghaïa, which forms a small, narrow valley with two slopes. One to the east, formerly belonging to the Saïdani and Ali Khodja farming estates, is now occupied by the Réghaïa hunting center, the national ringing center and a

pumping station Pumping stations, also called pumphouses, are public utility buildings containing pumps and equipment for pumping fluids from one place to another. They are critical in a variety of infrastructure systems, such as water supply, Land reclamation, ...

. The other, to the west, is occupied by the Douar Aïn El Kahla and the Domaine agricole de Boudhane. In the northern part of the valley, more or less fixed dunes stretch out, separating the mouth of the Oued Réghaïa from the

Mediterranean Sea The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern Eur ...

Pedology

The soil at Réghaïa lake tends to be sandy-loamy. The central part, on the other hand, is characterized by a fertile soil with a clayey tendency, and is made up of

brown soils and brownified red soils.

Hydrology

Lake Réghaïa is fed by groundwater from the Réghaïa marsh, which is fed by Oued Réghaïa, Oued Guesbaï, Oued Berraba, Oued El Biar, Oued Boureah and Oued El Hamiz. KoppenclassificationworldmapCs

Climate

Réghaïa lake is located in a region with a

Mediterranean climate A Mediterranean climate ( ), also called a dry summer climate, described by Köppen and Trewartha as ''Cs'', is a temperate climate type that occurs in the lower mid-latitudes (normally 30 to 44 north and south latitude). Such climates typic ...

, characterized by a 7-month wet season and a 5-month summer dry season. According to Emberger's climagram, the Réghaïa marsh is located in the sub-humid bioclimatic zone, characterized in particular by dry, hot summers and mild, wet winters.

Winds

Winds in Lake Réghaïa are usually light to moderate, predominantly north-westerly. The

sirocco Sirocco ( ) or scirocco is a Mediterranean wind that comes from the Sahara and can reach hurricane speeds in North Africa and Southern Europe, especially during the summer season. Names ''Sirocco'' derives from '' šurūq'' (), verbal noun o ...

blows on average 5 days a year, while thunderstorms are frequent, especially in winter and autumn with an average of 23.3 days/year.

Humidity

The wet season in Lake Réghaïa encompasses all three seasons (

autumn Autumn, also known as fall (especially in US & Canada), is one of the four temperate seasons on Earth. Outside the tropics, autumn marks the transition from summer to winter, in September (Northern Hemisphere) or March ( Southern Hemisphe ...

winter Winter is the coldest and darkest season of the year in temperate and polar climates. It occurs after autumn and before spring. The tilt of Earth's axis causes seasons; winter occurs when a hemisphere is oriented away from the Sun. Dif ...

and spring), while the dry season is

summer Summer or summertime is the hottest and brightest of the four temperate seasons, occurring after spring and before autumn. At or centred on the summer solstice, daylight hours are the longest and darkness hours are the shortest, with day ...

Climate summary

The climate at Réghaïa lake is

, with a 7-month wet season and a 5-month summer dry season.

Hydrological values

Réghaïa lake is characterized by flood spreading, groundwater recharge and sediment accumulation. The lake's actual functions are coastal erosion prevention,

flood control Flood management or flood control are methods used to reduce or prevent the detrimental effects of flood waters. Flooding can be caused by a mix of both natural processes, such as extreme weather upstream, and human changes to waterbodies and ru ...

, sediment capture and water quality maintenance. In addition to these functions, Lake Réghaïa irrigates 1,200 hectares of

farmland Agricultural land is typically land ''devoted to'' agriculture, the systematic and controlled use of other forms of lifeparticularly the rearing of livestock and production of cropsto produce food for humans. It is generally synonymous with bot ...

Ecological features

Réghaïa lake comprises 5 ecological habitats.

Maritime marsh

The Réghaïa maritime marsh plays an important role in containing and regulating wadi flooding, as well as preserving certain

ornithological Ornithology, from Ancient Greek ὄρνις (''órnis''), meaning "bird", and -logy from λόγος (''lógos''), meaning "study", is a branch of zoology dedicated to the study of birds. Several aspects of ornithology differ from related discip ...

species that nest there. The vegetation of this maritime marsh forms distinct zones in concentric circles around the lake.

Open water

The Réghaïa open-water lake is a permanent freshwater reservoir covering more than 75 hectares.

Dune belt

The Réghaïa dune belt, a natural barrier between the

and the maritime marsh, is made up of stabilized dunes. The vegetation, which grows in narrow strips along this coastal cordon, stops and fixes the sand, forming a barrier that closes off the mouth of the Oued Réghaïa.

Marine zone

The Réghaïa marine zone is located around the small Agueli or Bounettah island, which is a nesting ground for certain

species.

Scrubland

Réghaïa's scrubland forms a more or less narrow belt around the lake, providing good protection for

avifauna Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweight ...

. In such a diverse environment, the fauna is obviously very varied, with

herbivores A herbivore is an animal anatomically and physiologically evolved to feed on plants, especially upon vascular tissues such as foliage, fruits or seeds, as the main component of its diet. These more broadly also encompass animals that eat ...

and

carnivores A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose nutrition and energy requirements are met by consumption of animal tissues (mainly mu ...

contributing to the food chain of the maritime marsh.

References

{{Portal, Algeria Lakes of Algeria Ramsar sites in Algeria