Part of the movement. These mountains were formed when Africa collided with North America, and they are much higher than the Himalayas today. Today, traces of this mountain range can still be seen on the steep slopes of the eastern United States or the Appalachian Mountains. The Sierra Nevada in southern Spain was also formed in the same movement. It is divided into Morocco's Great Atlas Mountain (Middle Atlas Mountain, High Atlas Mountain and Anti-Atlas Mountain), Tel Atlas Mountain with short coast and Sahara Atlas Mountain with deeper and higher south. The last two are in Algeria.
Atlas mountain system is shaped like an elongated ellipse, and there is a vast complex of plains and plateaus between mountains. It includes different atlas of northern mountains and atlas of southern mountains and Sahara. Mountains form the edge of the vast plateau in eastern Morocco and northern Algeria. In the east, in Tunisia, they are connected with Mount Megill at Mount Tebesa; To the west, in Morocco, they join the towering and rugged peaks of Middle Atlas and Great Atlas. The anti-Atlas Mountains extend southwest from the Great Atlas Mountains to the Atlantic Ocean. Geologically speaking, Taylor Atlas is a young and wrinkled mountain range, which is related to the European Alps. However, sub-Saharan Atlas belongs to a different structural group, that is, the vast and ancient plateau group on the African continent. Atlas mountain system is shaped like an elongated ellipse, and there is a vast complex of plains and plateaus between mountains. It includes different atlas of northern mountains and atlas of southern mountains and Sahara. Mountains form the edge of the vast plateau in eastern Morocco and northern Algeria. In the east, in Tunisia, they are connected with Mount Megill at Mount Tebesa; To the west, in Morocco, they join the towering and rugged peaks of Middle Atlas and Great Atlas. The anti-Atlas Mountains extend southwest from the Great Atlas Mountains to the Atlantic Ocean. Geologically speaking, Taylor Atlas is a young and wrinkled mountain range, which is related to the European Alps. However, sub-Saharan Atlas belongs to a different structural group, that is, the vast and ancient plateau group on the African continent.
(1) water system. Seasonal rainfall is rainstorm, which determines the water system nature of atlas.
The dry riverbed of the Maghreb originates from the Atlas Mountains. Among the perennial rivers, Moulouya River originated in the middle of Atlas Mountain. The Cherif River rises in the Amur Mountains.
(2) soil. At the higher altitude in Atlas area, good soil is scarce, and there is often nothing except bare rocks, rubble and materials falling from landslides. There are two main substances: limestone and marl. Scarce sandstone is beneficial to the growth of forests. Alluvial soil is the best soil on terrace slopes and valley bottoms.
(3) Animals and plants. The soil in Atlas has been eroded and deteriorated due to lack of vegetation. Only about 65,438+0,065,438+0,000 square kilometers (39,000 square miles) have forests. In Reeve Mountain, Kabilie Mountain and Crumiri Mountain, which have little rainfall, the cork trees in their wet forests are covered with wild strawberry shrubs and rhododendron shrubs, and there are also half-day flowers and lavender everywhere. When the rainfall was less than 762 mm (30 inches) and there was limestone, green oak trees and golden cypress were covered with soil, forming a bright and dry forest and a thin and dense understory. The taller ones are dominated by snow pine trees. In the Sahara Atlas dry peak, vegetation is reduced to sporadic green oak trees and juniper trees.
Agricultural reclamation reduced the forest coverage of Atlas Mountains; Animals also retreated. There are only a few jackals and some monkeys left, and occasionally a group of wild boar appears in the oak forest. Berbers live in the mountains. They keep their own language, traditions and beliefs, and at the same time accept a certain degree of Islam.
Berber society pays attention to maintaining its own characteristics, which has been proved in the choice of residence. Villages with fortresses generally live on the top of high mountains. Although small in scale, this village includes houses, mosques, threshing floors and meeting places for Presbyterian church, which manages the affairs of each community. Families live separately in rooms around quadrangles.
Shilu of Great Atlas in Morocco lives in a valley deep in the mountains. Their village is always located at an altitude of over 2000 meters (6500 feet). Each village has hundreds of residents who live in row houses, and each house is next to another house, often with the fortress threshing floor as the primary position, or around the threshing floor and the houses of powerful families. The nearby hillside is divided into pasture and farm. Some non-irrigated fields use dry seed method to grow grain. The water used to irrigate the land is drawn from major rivers, and this kind of land can be harvested twice a year-planting grain in winter and vegetables in summer. Passers-by use cow dung as fertilizer. Raising livestock is increasing. Cork, the main commodity of forest production, has also brought considerable income.
Reeve in Morocco and kabir in Algeria are very similar in many ways. The Berber tribes on both sides live on the same wet hillside covered by oak forest. They are also obsessed with barren land and tend to live in isolation. Different from the lifestyle of Berbers in the Great Atlas Mountains and the Middle Atlas Mountains, animal husbandry plays a secondary role in their rural life. They grow some sweet sorghum (as feed), while women grow vegetables in the small garden next to their house. But their main income is fig trees and olive trees on the hillside where they live. Kabyle is also a skilled craftsman who can process wood, silver and wool. They used to be vendors, selling carpets and jewels to people on the plains.
The Orasi Mountains, located in the northeast of Algeria alone, are probably the least developed mountains in the Maghreb region. Shawia〔Chaouia〕] is a resident, living a semi-nomadic life, part farming and part nomadic. They live in a terraced stone village with rows of houses, which are fortified granaries. When winter comes, the residents of the highland valley will take their sheep to the lowlands around the hills, camp there or live in caves. In summer, they return to the highlands, irrigate the land where sorghum and vegetables are planted, and maintain apricot trees and apple orchards, while shepherds take their sheep to the pasture on the top of the mountain.
Despite the unstable living conditions, Atlas Mountain is still crowded with people-even in some places. For example, the population density around Cabilla Tizi Ouzou is 270 people per square kilometer (700 people per square mile). (1) resources. Although the Atlas Mountain is desolate and inaccessible, it still plays an important role in the modernization of Maghreb countries. The construction of water storage dam can not only store a large amount of water for irrigation plain, but also make hydropower generation possible. In Morocco, the dam was built on the northern slope of Great Atlas, crossing the el-Abid and el-Rhira rivers, while the dam on the southern slope crossed the Draa and Ziz rivers. Hydroelectric power stations have been developed in kabylie district of Algeria, which are located in Agrioun River and Djendjene River respectively.
The geological structure of Atlas is rich in minerals, among which lead, zinc, copper, manganese and phosphate are the most important. These raw materials are usually processed in coastal towns. For example, iron ore from Ouenza is supplied to the ironmaking industry in annaba.
Among forestry products, cork is more important than wood, and the production is concentrated in kabylie district, especially in Collo Massif.
Tourism is also very developed, especially in the Greater Atlas area of Morocco, Africa.
(2) Transportation. Atlas Mountain has its own internal transportation system. These villages are connected by paths. Go out or walk, ride a mule, or take a local bus.
Hills hinder traffic, and roads and railways have to be crossed by tunnels or viaducts, which is expensive. However, these mountains have many natural connections or passages to provide convenience. Nomads use an inclined narrow channel (that is, a channel formed by folds in the rock, and the strata in the rock sink from both ends to the center) to separate the ridges of the Sahara Atlas Mountains. Bisquerra Gap is located between Ouled-Nail and Oré s mountains, and has a natural passage, which is convenient for traffic between Constantine in Rhumel River and Touggourt in Sahara Desert. Both roads and railways between Algeria and Morocco pass through Atlas along the Tacha Pass, cutting off the continuity between Rif and Central Atlas. The passage is a natural road across mountain obstacles, which constitutes a strategic point. For example, Tiziwuzu, the transportation center of Grand Cabilla, is at the Genet Pass, which has actually become the capital of the hill. The ancient motorcade route from Marrakech to Della Canyon used the nTest Pass, so this passage became an extremely important commercial place. The attempt of European powers to control northwest Africa began in the15th century. Portugal's activities are limited to the Strait of Gibraltar and the Atlantic coast of Morocco, where they have established several forts. Spain's activities began in16th century, including seizing Mediterranean ports and gradually infiltrating inward, first in Rive area, and then in other parts of Morocco after 1860. France's influence was relatively extensive, starting with the occupation of Algiers in 1830, and finally extending to areas outside Atlas Rivian, including the exercise of protectorate power over most parts of Morocco (19 12 ~ 1956). Roads are built to control mountainous areas, facilitate the movement of people and goods, and thus improve the traffic level in once isolated and scattered areas, which are often ignored by government authorities in lowlands. Today, Atlas Mountain is no longer the focus of exploration and development in Europe, but a remarkable place in Moroccan, Algerian, Tunisia and other independent countries.