User:Riad Salih/sandbox/Oran

Oran (in Arabic: وهران, Wahrān; in Berber: ⵡⴰⵀⵔⴰⵏ, locally pronounced /wɑhren/), nicknamed "the Radiant" (in Arabic: الباهية, el-Bāhia) and "the Joyful", is the second-largest city in Algeria in terms of population and one of the most important cities in the Maghreb. It is a port city located on the Mediterranean Sea in the northwest of Algeria, 432 km from the capital city of Algiers. Oran is the capital of the province (wilaya) of the same name and is situated along the Oran Gulf.

The city is located at the bottom of a bay that opens to the north and is directly dominated by the Aïdour Mountain (or Murdjajo) to the west, which reaches a height of 580 meters, as well as the Moulay Abdul Qadir Gilani Plateau. The urban area extends on both sides of the Oued Rhi ravine, which is now covered.

Founded in 902 by the Andalusians, Oran has witnessed a succession of Arab-Berber dynasties. It was occupied by the Spanish in 1509 but was re-conquered in 1792 by Bey Mohamed el-Kebir, after an earlier period of occupation between 1708 and 1730. Oran then became the seat of the Western Beylik. During French colonization, the city experienced rapid development and became the second-largest city in Algeria. After independence, it remained the economic capital of the western region of the country and the main financial, commercial, and industrial center.

In 2008, the municipality had a population of 609,940 inhabitants, while the population of the Oran metropolitan area was approximately 1,000,000. By 2020, official estimates of the urban area indicated a population of 1,760,685 inhabitants. Therefore, Oran is both the second-largest city and the second-largest urban area in Algeria.

Localization
Oran, the capital of the province of the same name, is one of the 26 municipalities within this administrative division and the second-largest city in Algeria after Algiers. Located in the northwest of the country, on the southern shore of the Mediterranean basin, it is situated at the bottom of a bay that opens into the Gulf of Oran, approximately 432 km from Algiers. The closest neighboring cities are Mostaganem (80.9 km to the east), Sidi-Bel-Abbès (89.3 km), Mascara (97.7 km to the southwest), and Ain Témouchent (73.5 km to the west).

Geographically, the municipality of Oran is bordered by the Aïdour Mountain to the west and the Moulay Abd al Qadir al-Jilani Plateau (also known as Moul-el-Meida) to the south. According to the current administrative division, it is surrounded by the municipalities of Mers El Kébir to the west, Misserghin to the southwest, Es Senia to the south, Sidi Chami to the southeast, and Bir El Djir to the east, constituting its immediate suburbs.

Relief
Oran is nestled in a natural bay, backed by the foothills of Mount Aïdour. Overlooking the city is its iconic Santa-Cruz Fort, which stands at approximately 429 meters. The city's first urban core emerged along the banks of the Raz el-Aïn ravine. It then expanded eastward and southeastward onto a limestone plateau that opens up to a semi-arid coastal plain in the hinterland.

The waterfront sits at an elevation of 4 meters, while the Gambetta cliffs rise to over 50 meters. The city gradually slopes upward, reaching 70 meters on the Karguentah plateau and 90 meters in the suburb of Es-Senia. Formerly present ravines, traversing the current city location, have been partially or completely filled due to urban expansion, such as the Aïn-Rouina, La Mina, and Ravin Blanc ravines.

Located 15 km southwest of the city of Oran is the Sebkha d'Oran, an endorheic lake spanning over 40,000 hectares. It is the second-largest sebkha in Algeria. Fed by several wadis, it plays a crucial role in the region's environment, regulating the local climate and recharging groundwater aquifers.

In addition to the city itself, the surrounding area of the province offers an exceptional mountainous panorama. To the east, the Lions Mountain rises to 587 meters, while the Djebel Orousse range peaks at 628 meters at Djebel Sidi Driss. Other significant summits in this range include Djebel Tafrent at 589 meters. To the southeast, Djebel Sidi Aissa dominates at 789 meters, and finally, the Tessala Mountains reach 1,048 meters to the south.

Geology
The geology of Oran constitutes a fundamental element of its identity and heritage. Understanding the various geological components of the region allows for a better comprehension of the landscapes, local natural resources, and local history. Moreover, the Oran region possesses significant natural resources, including mineral resources, construction materials, substantial groundwater reserves, and thermal water sources.

The geology of the municipality of Oran is rich and complex, reflecting the region's tumultuous geological history. This wealth can be understood by examining its regional context and subdividing it into distinct geological units.

The Gulf of Oran Basin, consisting of marine sediments and marls from the Miocene and Pliocene periods, constitutes the majority of the region. These sedimentary rocks, primarily composed of limestone, sandstone, shale, and clay, contain fossils and traces of ancient organisms.

This basin is adjacent to the ancient Murdjajo Massif, formed of metamorphic rocks and magmatic rocks from the Paleozoic and Triassic periods during the Alpine orogeny. This massif, covering an area of approximately 600 hectares, is located between the African Plate and Eurasian Plate.

To the south of the Gulf of Oran, there extends a limestone plain with a thickness of about 200 meters, rising to an average altitude of 100 meters. Formed by Quaternary alluvium and upper Miocene marls, it developed approximately 10 million years ago in a shallow marine environment. The surface of the plateau, generally flat, is sometimes punctuated by hills and mounds and dissected by several ravines or wadis. The erosion of the Oran limestone plateau has created a rugged landscape with cliffs, ravines, and caves. This erosion has also influenced human settlement in the region, promoting the establishment of populations in more sheltered areas and providing natural resources.

The Oran region is located in a convergence zone between the African and Eurasian plates, resulting in the formation of the Tell Atlas mountain range. Over the centuries, the region has experienced several major earthquakes, placing it in a moderate to high seismicity zone. The subduction of these plates also generates deep earthquakes that are perceptible at the surface. These seismic events are caused by major faults that traverse the region, notably the east-west Oran Fault and the Tell Fault, which runs along the Mediterranean coast. Scientific studies have attributed a high seismic risk to the area, with the possibility of a major earthquake of magnitude 6 occurring in the near future.

Water Supply Sources
In the absence of precise data for the municipality of Oran, the statistics of the Oran province shed light on the sustainable management of water resources at the local level. Indeed, the distribution of consumption within it is as follows: 60% for drinking water supply, 10% for the industrial sector, and 30% for the agricultural sector. However, production is estimated at 300,000 m³ per day, while the deficit is about 70,000 m³ per day. Oran represents approximately 60% of the total demand for drinking water in the province, considering the projected figure of 464,000 m³ per day by the year 2030.

Faced with the increasing demand for water and the challenges posed by drought and climate change, the Algerian government has committed to a multidimensional strategy to ensure water security in the country. This strategy revolves around several key areas, including diversifying the sources of supply through dams, mobilizing unconventional water sources, and improving distribution infrastructure.

The water supply in the Oran region mainly comes from three sources: dams, groundwater, and desalination plants. The latter contribute to meeting the growing demands of an increasingly demanding population, industry, and agriculture.

Dams: The Oran province is primarily supplied by the Cheliff dams in the Mostaganem province, accounting for 52% of the total supply (with a capacity of 50 million m³), the Gargar Dam in the Relizane province (with a capacity of 45 million m³), the Kerrada Dam in the Mostaganem province (with a capacity of 70 million m³), and finally the Beni Bahdel Dam in the Tlemcen province (with a capacity of 54 million m³).

Desalination: The El Mactaa station, located in the Mostaganem province, was inaugurated in 2014 with a production capacity of 200,000 m³ per day. A second station with a capacity of 300,000 m³ per day is under construction in Cap Blanc.

Wells: Production is estimated at 160,000 m³ per day. The number of wells has increased by 50% since 2002, totaling over 120 operating wells, including 25 deep and horizontal wells. The introduction of modern and efficient drilling techniques has allowed for accessing deeper deposits and increasing production.

A network of pipelines and pumping stations transports water to households and economic infrastructure. Reservoirs and water towers are used to store and regulate the pressure in the network. Two main companies manage water distribution in the Oran province: Algérienne des Eaux (ADE), responsible for distribution in most municipalities, and Société de l'Eau et de l'Assainissement d'Oran (SEOR), responsible for drinking water distribution and sanitation in Oran.

Groundwater
The aquifer system in the municipality of Oran is characterized by an impermeable substrate beneath the Oran plateau. This substrate prevents the infiltration of rainwater and the replenishment of groundwater. Additionally, lateral facies changes (geology) affect the composition and permeability of rocks horizontally, impacting the water circulation. The complexity of the system makes it difficult to locate and exploit groundwater, increasing the risk of groundwater contamination. The presence of impermeable layers can limit the system's natural purification capacity. The water supply in Oran is crucial as water is insufficient and often highly saline due to low precipitation, which does not guarantee sufficient and consistent supply.

Natural Sources
Due to its geographical location and level of urbanization, the municipality of Oran has few natural water points. However, the Oran province is home to other valuable water points scattered across its territory, playing an important role in the city's water supply. The only perennial water source in the municipality of Oran is Ras El-Aïn, also known as Aïn Blal spring, with a relatively constant flow. It originates from the head of a ravine that extends for about 5 kilometers. Its meandering course sometimes reaches significant depths, increasing the risk of flooding in the region during heavy rainfall. In the past, other ravines shaped the landscape of the Oran plateau, hosting several springs. However, they have disappeared from the surface and flowed into an underground network due to urban expansion since the beginning of the last century.

Wetlands
The municipality of Oran does not have any wetlands within its boundaries. However, it is important to note their presence in its vicinity and immediate suburbs. These wetlands play a crucial role in water purification, naturally filtering polluted water and contributing to the improvement of drinking water quality. They also regulate the hydrological cycle by absorbing and storing rainwater, thereby reducing the risk of floods and recharging groundwater.

The Oran province hosts several wetlands of national and international importance, classified as Ramsar sites since 1983. Among the most significant are:


 * Lake Télamine, located about 10 km southeast of Oran. This salinelake covers an area of approximately 1,200 hectares and serves as a stopover for migratory birds.
 * Marais d'Arzew, situated near the town of Arzew, is a coastal wetland that covers an area of about 1,000 hectares. It is home to a rich biodiversity, including various bird species.
 * Lake Oubeïra, located east of Oran, covers an area of approximately 600 hectares. It is an important breeding and wintering site for waterfowl and supports a variety of aquatic plants.
 * Sebkha of Oran, a salt lake located northeast of the city, covers an area of about 5,000 hectares. It plays a crucial role in the water balance of the region and provides habitat for numerous bird species.

These wetlands are protected areas, and their conservation is essential for maintaining ecological balance and preserving biodiversity. They contribute to the overall water management in the region by providing natural purification and water retention functions.

In conclusion, the water supply in the municipality of Oran relies on a combination of sources, including dams, desalination plants, and groundwater. The Oran province, in which Oran is located, faces challenges related to water scarcity and increasing demand. The government has implemented strategies to ensure water security, including diversifying supply sources and improving infrastructure. While Oran itself has limited natural water points, nearby wetlands play a significant role in water purification and hydrological regulation.

Fauna and Flora
Understanding the ecosystems, fauna, and flora of urban areas, such as Oran, is complex. This difficulty revolves around several points: the lack of scientific data, which makes modeling and predicting their behaviors difficult, and their lower value compared to natural ecosystems. Despite these challenges, it is crucial to take an interest in these urban ecosystems as they host a significant portion of the population and have a significant impact on the environment.

Fauna
Due to complete urbanization, the region of the city of Oran exhibits fauna characteristic of anthropogenic environments. This wildlife community consists of opportunistic and adaptable species that thrive in proximity to humans, exploiting ecological niches provided by the urban environment.

Mammalian Fauna
Among the most representative mammalian families, one can mention Canids and Felids (dogs and cats), as well as bats and other species such as murids (brown rat, black rat, and gray mouse), which easily adapt to various environments. In addition to the mentioned species, the proximity of urban areas to the Murdjajou mountain range attracts certain wild species in search of food. Among the most frequently observed are European wild boars, mongooses, hares, and rabbits. More rarely, due to habitat fragmentation at the edge of urbanized areas, one can catch a glimpse of the African golden wolf and exceptionally, in isolated cases, the golden jackal, African wildcat, or striped hyena.

Other domestic species can be mentioned, although they may not necessarily be visible in urban environments. They are present on the outskirts near agricultural areas. Among these species, one canmention donkeys and mules, bovids (cows, sheep, and goats), or more rarely equids such as the Atlas horse, Arabian horse, or Anglo-Arab (a crossbreed of the two breeds).

Avifauna
The avifauna of the Oran region is distinguished by its richness and diversity, typical characteristics of the Mediterranean basin. It is home to a multitude of bird species, a significant proportion of which are migratory. Its geographical location and climate make it an important stopover on migratory routes, providing birds with a place to rest and feed before continuing their journey.

The variety of habitats present in the Oran region is a determining factor in the composition of its avifauna. From wetlands to marine and coastal mosaic environments, as well as specific flora in the region, this diversity offers a suitable environment for a wide variety of species.

Herpetological and Entomological Fauna
The Oran region is home to a remarkable richness and diversity of herpetological and entomological biodiversity. This richness can be attributed to the region's proximity to various habitats, such as the mountainous reliefs of Mudjajou and Lion Mountain, wetlands like Daiat Morsly, and the Canastel Forest. Indeed, this variety of ecosystems provides an ideal refuge for numerous species of reptiles, amphibians, and insects. Additionally, the Mediterranean climate, with its mild winters and hot summers, is particularly favorable for the reproduction of many species.

Among the most remarkable species, one can mention reptiles such as the common chameleon, Arzew viper, and ocellated lizard. Amphibians like the green frog and common toad, insects like the swallowtail butterfly, beetles like the sacred scarab, and Hymenoptera such as bees and wasps.

This biodiversity in the Oran region is a valuable asset that deserves to be studied, protected, and valued. It is important to note that the fauna of Oran is threatened by several factors, including habitat destruction, pollution, and climate change. Therefore, it is essential to implement conservation measures to protect this exceptional natural heritage.

Marine Fauna
The Gulf of Oran, with an area of approximately 2,000 km² and reaching depths of 1,200 meters, offers a unique diversity of marine habitats. Its rugged coastline, dotted with bays and capes, and its islands such as Habibas and the Paloma Peninsula serve as refuges and breeding areas for a multitude of species.

Over 800 species of fish, 100 species of crustaceans, and 50 species of echinoderms are found in the region. Shimmering shoals of sardines, anchovies, and mackerels feed predators such as tunas, bonitos, and barracudas. The seabed is home to a multitude of demersal fish: groupers, sea breams, red mullets, and pandora fish inhabit rocks and seagrass beds, while soles and plaices camouflage themselves in the sand.

This unique location also provides a refuge for a multitude of fascinating invertebrates. Red corals build protective reefs, pearl mussels filter the water, and crabs, shrimps, and lobsters traverse the seafloor. Purple sea urchins and Neptune's sponges contribute to the balance of this environment by grazing on algae and filtering the water.

In addition to its rich marine life, this place is home to a diversity of fascinating marine mammals. Common, blue, and white dolphins, Risso's dolphins, and bottlenose dolphins roam freely in these waters. Occasionally, common fin whales and sperm whales can be spotted. The endangered Mediterranean monk seal is rarely observed in this area.

Marine pollution, accidental fishing, and climate change pose serious threats to the survival of marine life in this area. Protective and sustainable management measures are necessary to preserve this unique ecosystem.

Flora
The flora of Oran is rich and diverse, reflecting the Mediterranean climate of the region and the complex history of the city. It encompasses a wide variety of plants, from trees and shrubs to herbaceous plants, ferns, and spore-bearing plants.

Diversity and Distribution
With numerous species distributed across various habitats, the flora of Oran showcases a typical Mediterranean character. It consists of three main groups: flowering plants, non-flowering seed plants, and spore-bearing plants. This plant diversity reflects the temperate climate and diverse soils of the region, resulting in a rich and colorful botanical landscape.

Habitat
The variety of landscapes in the region is reflected in the diverse habitats of plants, including aquatic, terrestrial, halophytic, and mountainous environments. This diversity is also evident in the origin of species, with indigenous and exotic plants coexisting. The uses of plants are equally diverse, ranging from food to medicine and ornamentation.

Botanical Composition
The flora of the Oran region stands out for its richness and diversity, with approximately 2,200 species grouped into four main categories. The dominant group is the Magnoliophytes with 1,800 species, followed by Bryophytes (250 species), Pteridophytes (80 species), and Gymnosperms (48 species). This remarkable floral diversity reflects the different types of habitats present in the region, including coastal areas, inland mountains, wetlands, plains, and forests.

Floristic Composition
The flora of the region is characterized by a unique blend of indigenous and exotic species. Among the indigenous species, the dominant ones in the landscape include pine, holm oak, juniper, mastic, rosemary, and thyme. Common exotic species found in the region include eucalyptus, prickly pear cactus, palm trees, and plane trees, which add diversity to the local vegetation.

Floral Environment
Nestled against Mount Aïdour to the west, Oran is naturally bordered by a rugged mountain range. This unique geographical configuration provides a distinct biotope for many plant species on the outskirts of the city, creating a distinct ecosystem within a dense urban environment. The slope closest to the city is dominated by Aleppo pines, prickly pear cacti, and agave plants, while Barbary thuja thrives in rocky areas and Phoenician juniper along the coastal parts. As one moves away from the urban area, evergreen oaks become the dominant species in the massif, often accompanied by Aleppo pines. The Atlas cedar, also present, prefers higher and more humid altitudes, while mastic can be found in maquis and garrigue vegetation.

Urban Areas
Upon entering urban areas, a specific organization of flora becomes apparent. Along the city's main thoroughfares, one can observe the presence of street trees, often including fig trees, palm trees, eucalyptus, plane trees, rubber fig trees, laurels, Acacia dealbata, or orange trees. As one moves away from the city center towards the outskirts, the plant composition evolves, with a predominance of species adapted to different urban contexts.

Green Spaces
In addition to street trees, the city boasts a diverse flora in its green spaces. Legacies from the colonial era, such as the Étang promenade and the public garden, stand out with the presence of both indigenous and exotic species, as well as century-old trees. Notable examples include bird of paradise flower, tamarisk, Blépharocaryum, mastic, bougainvillea, hibiscus, iris, jasmine, Melia azedarach, Jacaranda, and Grevillea robusta. Finally, ruderal species such as field bindweed, dandelion, and nettle, which easily adapt to disturbed environments, complete the city's botanical landscape.

Marine Flora
The Gulf of Oran hosts a rich and diverse marine flora, influenced by the Mediterranean Sea and freshwater input from surrounding rivers. It includes brown, red, and green algae. Flowering plants such as seagrasses (Posidonia), eelgrasses (Cymodocea), and marine grasses (Zostera) are also represented.