The Nile is 6670 kilometers longworldThe longest river on the river.Although in 2007BrazilScholars claimed thatAmazonMore length, but not globalGeographyIt is generally accepted by the academic community.
The Nile Basin is divided into seven regions: East African Lake Plateau, Mountain River Region, White Nile Region, Blue Nile Region, Atbara River RegionKhartoum The Nile region and the Nile Delta to the north.This river flows throughTanzania、RwandaandUgandaFrom the west into Lake Victoria, Africa's largest lake.The main stream of the Nile originates from the lake, which is calledVictoria Nile。River crossingLake KeogaandLake AlbertAfter flowing out, it is called the Albert Nile, and when it joins the Sobat River, it is called the White Nile.The other one, which originates from the central Ethiopian highlands, joins the White Nile in Khartoum, Sudan, and then receives the last major tributary north of DamarAtbara River, called the Nile.The Nile flows northwestward in an S-shape and flows into Nasser Reservoir (lake) after passing through three waterfalls.The river flows out of the reservoir and enters through the Egyptian capitalNile DeltaAfter that, it is divided into several tributaries and finally injectedmediterranean seaEast end.
hydrology
Announce
edit
characteristic
The Nile has the characteristics of regular floodingSudanThe water level in the north usually rises in May, reaches the highest level in August, then gradually drops, and is low from January to May.Although floods occur regularly, the amount of water and the time of rising tide vary greatly.The reason for this phenomenon is that the Blue Nile andAtbara River, the water source of these two rivers comes fromEthiopian PlateauSeasonal rainstorm on.More than 80% of the Nile water is supplied by the Ethiopian Plateau, and the rest of the water comes from the East African Plateau Lake.When the flood comes, it will flood the farmland on both banks. When the flood recedes, it will leave a thick layersiltTo form fertile soil.Four or five thousand years ago, Egyptians learned how to master the law of floods and use the fertile land on both sides of the river.For a long time, the Nile River Valley has been a continuous cotton field with fragrant rice flowers.staysahara desertandarabIn the grip of the desert, the meandering Nile is like a green outline, full of infinite vitality.
White NileOriginated fromequatorRainy area with abundant and stable water.However, after flowing out of the plateau and into the basin, due to the extremely flat terrain, the water flow is unusually slowBotanyIt also delayed the advance of water flow, which evaporated strongly under the sunshine in low latitude dry areas, thus consuming huge amounts of water, and there was little water that could flow downstream.The annual average flow of the White Nile at the junction with the Blue Nile is 890 cubic meters per second, aboutBlue NileHalf of.The water in the lower reaches of the Nile mainly comes from theSobat River, Blue Nile andAtbara RiverAmong them, the Blue Nile is the most important.Sobat RiveryesWhite NileAs a tributary, it began to rise in May, and the highest water level appeared in November. At this time, the water level of Sobat River was higher than that of the White Nile. Backward irrigation was caused by pushing the latter, thus strengthening the evaporation of water in the upper reaches of the White Nile.The Blue Nile originates from theLake TanaThe upstream is located in the tropical mountainous and rainy area with abundant water resources.Due to the strong seasonal characteristics of precipitation, the river flow changes greatly within the year.The water volume is limited in spring. The water began to rise in June, then continued to rise rapidly and reached the peak in early September.During this period, it will also cause the White Nile to flow backward.The water level drops from November to December, and then the dry season begins.The minimum flow in dry season is less than 100 cubic meters per second, aboutFlood period1/60 of the maximum flow.Atbara RiverIt also originated fromEthiopian PlateauDue to the north location, the rainfall is more concentrated, and the drainage area is small, so the flow changes more.In winter, the river bed becomes a series of small lakes.
The Nile has a long reachdesertThere is only loss but no supply of river water.As the upper source of the river is tropical and rainy area, there is a huge flow, although a large amount of water is lost along the desert due to evaporation and leakagerunoffThe Nile can still maintain a river course with flowing water all the year round.A river like Nile, which is not gathered by local runoff but simply flows through, is called guest river.The local climate conditions have no positive effect on the formation of these "guest rivers", only negative effects.
The flood in the main stream of the Nile comes in JuneKhartoum （SudanCapital), reached the highest water level in September.The largest flood peak occurred in Cairo in October.Of the total water volume of the Nile, 60% comes from the Blue Nile, 32% from the White Nile, and the remaining 8% from the Atbara River.However, there are great changes in flood season and dry season.In flood periodBlue Nile68%, White Nile 10%, Atbara 22%;In the dry season, the water volume of the Blue Nile drops to 17%, and the White Nile rises to 83%. At this time, the Atbara River is cut off, and no runoff flows into it.The proportion and change of the above rivers in the Nile water volume are closely related to the precipitation and seasonal distribution characteristics of each river basin.
Water system composition
In the Pleistocene, there was a big lake between Juba and Khartoum, and the lake water was supplied by the existing blue and white Nile.Later, the lake water was higher than the edge of the basin, passing through thecanyon, flowing northward along the ancient Nile into the Mediterranean Sea, and then the Nile River system appeared.
Upstream section
Nimulai of Sudan（Nimule）The above is the upper reaches of the river, with a length of 1730 kilometers, which are called the Kagera River and the Victoria Nile from top to bottom(Victoria Nile)Albert Nile (Albert Nile)River.
The Nile has two sources. One originates from the 2621m tropical Central African mountain area, called the White Nile.The White Nile flows through Lake VictoriaLake KeogaSuch as the huge lake areaUgandaThrough Sudan.The other source of the Nile is the Ethiopian highland at an altitude of 2000 meters.It's called the Blue Nile.The total length of the Blue Nile is 680 kilometers. It passes throughLake TanaAnd then it turns straight down to form a torrent of water, which is the second famous waterfall in Africa - Tissate Falls.The roaring blue Nile is called the Nile when it meets the quiet white Nile after rushing into the Sudan Plain.
The Nile originates from the Ruvuvu River in Burundi and flows through the Kagera River after confluence with the Nyawalongu RiverRwandaandTanzaniaAndUgandaThe border area of the Lake Victoria.It is called Victoria Nile after flowing out from the north end of Victoria, and flows into the water system of the Nile River basin, as well as the built sluice and dam, which are shown in Uganda, and soon flows into Lake Kioga.And then flows westward through a section of flow to Lake Albert（Mobutu Lake）And the drop is 400m.After leaving Lake Albert, it flows northward, called Albert Nile, and receives the Apagal River flowing into it from the right bank. After passing Nimulai Gorge, it enters the Sudan Plain.The river from Nimulai is called White Nile,
Midstream section
From Nimulai to Khartoum is the middle reaches of the Nile River, which is 1930 kilometers long and is calledWhite Nile, of which Malakal is also calledJebel RiverThe largest tributary, the Blue Nile, flows into the lower reaches of Khartoum.Nimulai Malakal River Section is also calledJebel River。The 900 km section below Juba flows through the Sud swamp area.After leaving the swamp area, the right bank receives the Sobat River, and the river runoff is doubled.From then on until both sides of the Khartoum River are mostly semi desert areas.The whole journey from Nimulai to Khartoum is 930km, with a drop of 80m.
Downstream section
The confluence of the White Nile and the Blue Nile is called the Nile, which belongs to the lower reaches and is about 3000 kilometers long.The Nile crosses the Sahara Desert and enters north of CairoEstuarine deltaThe delta is divided into east and west branches and flows into the Mediterranean Sea.
In Khartoum, the Blue Nile River flows into Khartoum, and the later reaches are called the Nile River.The flow from Khartoum to Aswan is about 1850 km, with a drop of about 290 meters. Both banks are desert areas, and the Atbara River is the main tributary.The route from Aswan to Cairo is about 900 km, with a small drop.Starting from 20km downstream of Cairo, the Nile River enters the delta area, covering an area of about 22000-24000 square kilometers. There are many river branches and lakes. The largest river branches are the Dumyat River and the Reihid River, each of which is about 200km long.
Main tributaries
The main tributaries of the Nile River include Achuahua River, Ghazal River, Sobat River, Blue Nile River and Atbara River.
White NileIt is Burundi, the source of the Nile and the East African Plateau.The upper reaches of the Nile areKagera River, which originated fromburundiIn the territory, the downstream flows into Lake Victoria.Lake water channelOwen FallsIt flows into Lake Keoga and becomes famous after leaving the lakeVictoria Nile, and then flows into Lake Abbott via Cabarega Falls.The water of the lake flows out from the north end and is named Abbott Nile River.From Nimule, it is called White Nile.Among the tributaries of the Nile, the White Nile and the Blue Nile are the best known ones. One is graceful and the other is unrestrained. They are often described as "lovers".
The White Nile flows northward along the side slope of the East African Plateau. The valley is deep and narrow, with many rapids and waterfalls.From Boer to the north, the White Nile flows into the flat and shallow swamp basin, with slow water flow, and a large number of aquatic plants dominated by papyrus grow in the river.After flowing northward out of the basin, the White Nile meets the Sobat River, the Blue Nile River and the Atbara River, and there are no tributaries below.britainThe explorer John Henning Spike discovered the "source" of the Nile in Lake Victoria on July 28, 1862. At that time, the total length of the river was calculated to be 5588 kilometers. Later, he found that the farthest source wasburundiEast African lake regionKagera RiverThe birthplace of.
Blue Nile
Blue NileIt is the largest tributary of the Nile, with a total length of about 1700 kilometers and a drainage area of 325000 square kilometers.It originates from Gojim highland in Ethiopian plateau and flows northward into Tana Lake, which is called Little Abay River.The Blue Nile flows out from the southern end of Tana to the border of Sudan, called the Abay River. Due to lava obstruction, it bypasses the Birhan Peak (4154m above sea level) southwards and turns northwest into Sudan.
Blue Nile waterfalls
In the 860km flow, the riverbed drops 1320m, with a gradient of 1:650.There are many waterfalls and rapids along the way, the most famous of which is the Tis Assad Waterfall.It is located about 30km downstream of Bahar Dar on the south bank of Tana Lake, with a drop height difference of 45.8m.About 3 kilometers above the waterfall is the Arafami Waterfall, with a drop of about 6 meters.The Abay River twists and turns in Ethiopia, receiving many tributaries along the way.These tributaries are mainly concentrated on the left bank, including Bahiro River, Jama River, Mugar River, Didesa River and Dabus River, all of which are perennial rivers with water.There are few and small rivers on the right bank. The only tributary with water all the year round is the Boles River, which has steep slopes and rapid flows.Due to the rapid flow, the water loss in this reach is not large.As the source of the Blue Nile River is located on the Ethiopian plateau with distinct dry and wet seasons, it has abundant water and less loss along the wayhydrographic featuresIt is the opposite of the White Nile.These characteristics are as follows: ① large runoff; ②Large drop; ②The seasonal and interannual changes of flow are very large.
Kagera River
Kagela River is a river in eastern Africa.It originates from the southwest of Burundi and is formed by the confluence of the Ruvuvu River and Nyawalonggu River.Flow throughTanzania、Rwanda、Uganda, injectionLake Victoria, 400 km long.The upstream flows through the mountains, with Lusumo Falls;The downstream flow is stable, abundant and navigable.It is the longest river flowing into Lake Victoria and is usually considered as the upper source of the Nile.
Bahr Ghazal
The Shuai Shile River system, consisting of the Yei River, the Juer River, the Luor River and other rivers and lakes (most of which are seasonal rivers and lakes) originating in the southwest plateau of Sudan, flows into the Jebel River from the left bank. The marsh area of the Ghazal River lake area is 40000 square kilometers. Except for the Juer River, all other tributary lakes disappear into the marsh, and the amount of water flowing into the Nile River every year is very small.
Sobat River
Sobat River
The river flows northwestward and flows into the White Nile to the south of Malakal.It is a tributary on the right bank of the White Nile, formed by the confluence of the Barrow River and the Pibor River, with a total length of 730km from the source of the Barrow River and a drainage area of 250000 square kilometers. The rainy season is from June to December every year. The river is very large, and the maximum flow occurs in November.The average flow at the estuary is 412m ³/s.In rainy season, the 300km section from the estuary to Nasir City is navigable.
Atbara River
Atbara River is the last tributary of the Nile River. It originates from the Gondor region to the north of Tana Lake, with a length of 1120km.The main tributaries areTekeze River 。Tekeze River originates from the northeast of Ethiopian Plateau at 12 ° N and 39 ° 30 'E.It flows into Atbara River from Shuwak in Sudan, with a flow of about 864 km,Riverbed gradient1：800。Atbara River enters Sudan clay plain after receiving Tekeze River, and flows into Nile River at Atbara after a flow of about 500 km, with a gradient of 1:4000.
Although Atbara River and Blue Nile River originate from the Ethiopian plateau, they lack natural reservoirs like Tana Lake, so their hydrological characteristics are different from that of Blue Nile River:
① The annual average runoff is 12 billion cubic meters, which is one of the important tributaries of the Nile.
② ForSeasonal riverThe river bed dries up from January to May every year. The flood season is concentrated in July to September, and the maximum flow is 2037m ³/s in August.The river rises and falls sharply, and the seasonal variation of flow is more serious than that of the Blue Nile.
The Nile Basin starts from the East African Plateau in the south, reaches the Mediterranean coast in the north, and leans to the eastEthiopian Plateau, and alongCrimson SeaExtending to the northwest, adjacent to the westCongo Basin, Chad Basin and along the Mala Mountains, Great Gilev Gaoyuan andLibyan desertIt extends northward.
The geomorphology of the basin can be simply summarized as follows: the East African Plateau, which is mainly composed of crystalline rocks, and the Ethiopian Plateau, which is composed of lava, are located in the south and southeast of the basin, respectively;The whole Sudan is basically a huge country with a gentle slope from south to northTectonic basin, the Nile runs through it;The east and west sides of the Nile below Khartoum are vast desert platforms.
The upstream of the Nile is the Kagera River, which originates fromEast African PlateauBurundi.Both banks of the White Nile are flat, and bedrock is occasionally exposed.Around the confluence of the White Nile and the Green Nile is the Jizila Plain.The reach below the confluence point is called Nile River.The Nile flows through the sedimentary rock area north of Khartoum.The valley is a shallow canyon with a flat bottom.Wadi HalfaThe nearby valley is only 201 meters wide, and the valley from here to Aswan is very narrow.Below Aswan, the river valley is widened, about 16km to the Najahamadi area.The river course is close to the east bank, and the valley plains are mostlyHexi。There are 6 waterfalls between Khartoum and Aswan, which are all caused by the basement crystalline rock that forms the plateau on the east side of the valley extending westward into the valley.The valley walls on both banks are asymmetric, the east wall is high and steep, and the west wall is low and gentle.
The river source section from the river source to the outlet of Lake Victoria has obvious mountain river characteristics. The outlet of Lake Victoria to Nimulai has a riverbed gradient of 1:1200, and there is Kabarega Falls along the way.In addition to the plateau shallow lakes between the rift valleys such as Lake Victoria and Lake Kioga, the river reaches also run through the Mobutu Lake, Lake Edward andLake GeorgeAnd other fault lakes.
The Nile River flows through the vast Sudan clay plain with flat terrain and very gentle gradient. The gradient above Malakal is only 1:13900. There are many marshes along the way, and the river course is braided and overflowing.From Malakal to Khartoum, the riverbed gradient is more gentle, only 1:100000.
The lower reaches of the Nile can be subdivided into: ① the valley section from Khartoum to Aswan. The Nile River cuts through the vast desert valley and flows down, with a gradient of 1:6000.The crystalline rock is widely exposed, and the bed rock of the river bed is soft and hard, forming the famous six waterfalls; ②Aswan Cairo section, crossing eastWestern DesertThe river valley is wide and flat, and there are long and narrowriver flat, the gradient is 1:13000; ③The estuary section below Cairo starts roughly from 20km below Cairo. The river branches into the Mediterranean Sea, forming a huge Nile Delta, covering an area of 24000 square kilometers. The average thickness of the alluvial soil layer is more than 18m, and the surface is flat,river networkVertical and horizontal, densely distributed channels, and many coastal areaslagoonAnd sandbars.
climate
Announce
edit
The Nile Basin spans 35 ° latitude, and the climate in the north and south is quite different, showing obvious latitude zonality. At the same time, non zonal factors (mainly terrain) also affect the distribution of climate zones to a certain extent.
the Nile
Located in the southeast of the basinEthiopian Plateau, due to the uplift of the terrain, the climate appearsVertical band spectrumAnd has distinct dry and wet seasons.In summer, the air over North Africa and the Arabian Peninsula belongs to a low pressure zone, and the southeast trade wind from the South Indian Ocean crosses the equator and turns into southwest windGulf of GuineaThe moist and hot air flow ofWindward slopeUplift, forming a "heavy rain period" from July to September.In winter, the dry northeast wind from Southwest Asia prevails on the plateau, forming the dry season from October to February of the next year.From March to April, Sudan is located in the center of low pressurethe indian oceanThe surface attracts a moist airflow, forming a "light rain period" before the "heavy rain period" in most areas of the plateau.The plateau has an annual average rainfall of 1000~2000 mm, which is the most important rainfall center in the Nile basin.
The southern part of the basin and the northwestern part of the East African Plateau are not only affected by the humid air flow from the Gulf of Guinea, but also affected by theequatorIn the lake area, the solar radiation is strong and the convection is strong, so the rainfall is abundant. The annual average rainfall is 1200~1300 mm, and the seasonal distribution is relatively uniform: the monthly average rainfall is not more than 180~200 mm at most, and not less than 50~60 mm at least. There is no obvious dry season, and the relative humidity is about 70%. This is another rainfall center in the Nile basin.
From Nimulai to the north, the rainy season is shortened, the rainfall decreases, and the isohyets are basically zonal distribution.The rainy season occurs from April to October in southern Sudan and from July to August in central and northern Sudan.The annual rainfall in Khartoum is less than 200 mm, while the annual rainfall between Donggula and Cairo is less than 25 mm. There is often no rain in the south of Asiute all year round.Due to the influence of Mediterranean climateCairoFrom the north to the coast, the annual rainfall gradually increases from 25 mm to 200 mm, mostly in winter.
Integrated resources
Announce
edit
overview
The Nile is in AswanAverage annual runoffIt is 84 billion cubic meters, that is, the total water volume of the Nile.As the Nile flows through different natural zones,water resourceThe distribution of is also characterized by obvious latitudinal zonality.basinRunoff resourcesThe general trend is decreasing from south to north.At the same time, due to the influence of non zonal factors (topography), the latitudinal distribution of water resources is disturbed, forming the main water source areaEthiopian PlateauAnd the largest water consumption area - the vast marshes in southern Sudan, thus changing the water balance of the Nile Basin.Under the combined effect of zonal and non zonal factors, the spatial distribution of water resources in the Nile basin is extremely uneven, and regional differences are very obvious.
See the table of runoff resources in each basin of the Nile River system. There are 7 runoff areas listed in the table, of which 4 are water producing areas and 3 are water losing areas.
Due to the nature of the main and tributaries of the Nile RiverhydrologyThe characteristics and water resources are different from each other, so according to the characteristics of water resources, combined with climate, topography and other factors, the whole Nile basin is roughly divided into four regions:
Annual high water area of East African Plateau
It covers an area of 466000 square kilometers and is located inTropical rain forest、SavannaWith abundant rainfall, it is one of the two major rainfall centers in the basin.Due to the uniform distribution of rainfall season and the regulation of many lakes, the runoff changes little. The riverbed gradient in this area is large, and there are many waterfalls and rapids along the way, including Lusumu, Owen, Kabarega and Fula Falls.Hydropower resourcesIt is relatively rich. The potential hydropower resources of Kabarega Falls alone reach 5 billion kW · h.
Plateau seasonal wet area
Nile Basin Map
In addition to the Blue Nile and Atbara River basins, this area also includes the upper reaches of the Sobat River, with an area of about 469000 square kilometers.natural landscapeIt has a vertical band spectrum and abundant rainfall, but the seasonal distribution is very uneven. Most of the rainfall is concentrated in May to September.The dry and wet seasons are distinct, and the river rises and falls sharply, forming obvious flood and dry seasons.This area provides 89% of the annual runoff of the main stream of the Nile, and is the main water source of the Nile basin.
Due to the large drop and large amount of water, the hydropower resources are the most abundant.The water energy reserve of the Blue Nile River basin in Ethiopia alone is 172 billion kW · h, and the economically exploitable water energy resources are 38 billion kW · h.
Swamp water loss area
Range from Mongla toKhartoum , including the Jebel River, the Ghazal River, the middle and lower reaches of Sobat and the White Nile, covering an area of 894000 square kilometers.Natural landscape from south to northSavannaTransition to semi desert.The average annual rainfall is reduced from 946 mm (Mongla) to 167 mm (Khartoum). The decline in this area is very slow, and swamps are widely distributed.Evaporation consumption is high, and water loss in marsh is serious.
Water supply
It covers an area of 1.051 million square kilometers from Khartoum to the estuary (except Atbara River basin). The natural landscape is tropical desert, with little rainfall and strong evaporation.This is a desert water loss area whose runoff completely depends on upstream supply.
In the section from Khartoum to Aswan, the river is deeply incised, with six waterfalls and abundant hydropower resources。
development
On average, the Nile Basin is a region with water shortage.Due to the level of economic development of all countries in the basin, the utilization of water resources is still dominated by farmland irrigation. Besides Egypt, the shortage of water resources is not prominent. However, with the economic development of all countries and the improvement of people's living standards, the water source will be seriously insufficient. Countries in the basin need to strengthen cooperation to reasonably and fully develop the Nile water resources.In order to dynamically reflect the whole process of improving the level and expanding the scope of water resources development and utilization, the following five stages are described in chronological order, marked by the main ways of river water utilization.
Before the 1920s
This period is characterized by the development of flood diversion and flood irrigation, and the construction of water storage reservoirs, which use gravity flow for water diversion and water lifting for irrigation.
the Nile
The development and utilization of Nile water resources began in the desert water loss area.In Egypt, hydrologic survey and river water development and utilization have a history of at least 5000 years. As early as 3400 BC, Egypt had mastered the regular flooding of the NileNile Valley Flood diversion and flood irrigation to develop agriculture.With the passage of time, a traditional irrigation method - embankment irrigation has gradually formed.During the flood season every year, the flood is introduced into dikes with different areas through canals. The water depth is 1 to 2 meters, and it stays for 40 to 60 dayssiltIt becomes an annual precious source of fertilizer.When the water level of the river drops, the trapped water flows back to the Nile, which means sowing wheat, beans and other crops.In addition to flood diversion and flood irrigation, over irrigation reservoirs are also built and water lifting irrigation is adopted.It is said that between 2700 and 2600 BC, Egypt built a dam called Elfara on a river called Wadigarawa, 30km east of Cairo, to hold back the flood in the mountain area.A long time ago, Egypt had bucket irrigation, butIrrigation areaIt is not large, and the content of alluvium is very low, so it can not fertilize the field.In addition to Egypt, similar traditional irrigation agriculture has also been developed along the Nile River in northern Sudan.
From the 1920s to the early 20th century
The characteristic of this period is to build sluice to back up water, divert dry water for irrigation, and improve farmland multiple cropping index while continuing flood diversion and flood irrigation.
The beginning of large-scale perennial irrigation began in the 1920s, and the Nile bank was improved in 1826Ding ChengThe deep canal system was excavated, thus increasing the irrigation area.In 1843, Egypt decided to build a sluice on the Nile to control and raiseDry water levelFlood discharge is recommended for perennial irrigation wells.In 1861, Duoxian built two sluices, namely delta sluice, on Rosetta and Dumyat tributaries, 23 kilometers north of Cairo.This is the first large-scale backwater project in the Nile.It marks that Egypt's irrigation has entered a new era.By the beginning of the 20th centuryZivTa, AsiuteIsnerThe completion and use of the sluice and backwater project have enabled Egypt to obtain irrigation water in the dry season. From the traditional embankment irrigation to perennial irrigation.The irrigation area of Egypt increased from 1.26 million square meters in 1820 to 2.27 million square meters in 1907, and the corresponding multiple cropping index also increased from 1 to 1.43.
Early 1960s
The characteristic of this period is to build an annual regulation reservoir, regulate the annual internal flow, improve the utilization of annual runoff, and start the comprehensive utilization of the river.
Nile landscape in Aswan
With the expansion of perennial irrigation, the increase of multiple cropping index, and the continuous increase of water demand for multiple cropping crops, the natural runoff has been insufficient for irrigation, so the goal of further development and utilization has turned to a large number of flood season floods mainly from seasonal high water areas.In order to store flood and relieve drought, Egypt built the first dam on the Nile in Aswan in 1902Aswan Old DamThe reservoir capacity is 1 billion cubic meters, and the irrigation area is 168000 square meters, which is the earliest modern water storage project in the Nile.The old dam has been raised twice. In 1912, it was increased by 6 meters, and its storage capacity increased to 2.5 billion cubic meters, with an additional irrigation area of 80000 square meters. From 1932 to 1933, it was increased for the second time by 8 meters, and its storage capacity reached 5 billion cubic meters, and its dam height reached 83 meters, increasing the irrigation area.10000 square meters, irrigation area of 32.8 square meters, and one on the left bankhydropower stationThe dam is also equipped with navigation locks.In 1937, Egypt built the Jebel Oria Dam on the White Nile, 48 kilometers south of Khartoum in Sudan, with a storage capacity of 3.5 billion cubic meters. In the dry season, Egypt released water to Egypt, with an irrigation area of 337000 square meters.
In addition to the construction of the above dams, Egypt also built the Naja Hamadi sluice (1930) and the Idefena sluice (1950), and reinforced, reconstructed or rebuilt other sluices.
Thus, Egypt has a completeirrigation system。The left bank of Isna sluice is the Asi wind channel, which is 125km long, and the right bank is the Karabia channel, which is 225km long.Above the Najahamadi sluice gate, there is the east and west Najahamadi canal.There is Ibrahimia Canal on the left bank of the Asiute Gate, 317km long, with a summer flow of 30~80m ³/s and a flood period of 500~900m ³/s, which is one of the largest irrigation canals in the world.In addition, another Yusuf River leads water from this canal to Fayoum Oasis.These canals are roughly parallel to the Nile and irrigate the narrow strip on the west bank of the Nile.There are 4 main canals in the delta area, Ismailia Canal, Taufik Canal, Minufu Canal and Bumera Canal.The Ismailia Canal is 123km long, with a flow of 100m ³/s, and connects Egypt to the eastSuez CanalIn addition to irrigation, it can also be used for navigation.All ten canals are divided into many branch canals in turn to form a strict irrigation network.In 1966, the total length of irrigation canal reached 25500 kilometers.
The irrigation canal discharges water from February to December every year, and stops water for annual maintenance in January. The irrigation method is rotation irrigation, and the rotation irrigation period varies with crops.
In addition, Egypt also attaches great importance to drainage. In 1964, the total length of drainage channels was 22000 kilometers, including 12000 kilometers of concealed pipe drainage. The main and branch channels for holding water have initially formed a system.At the same time, Egypt also vigorously develops water lifting irrigation and controls gravity flow irrigation.
The perennial irrigation in Sudan began in the 1920s.The vast area between the Blue and White NileJazira PlainIt has favorable conditions for developing large-scale gravity irrigation agriculture.In 1925, the Sennar Dam was built on the Blue Nile, with a storage capacity of 780 million cubic meters. Since then, gravity irrigation has replaced pump pumping irrigation, and the cotton planting area has expanded rapidly. From 1951 to 1952, the Sennar Dam was heightened and expanded, and the storage capacity has increased to 930 million cubic meters.From 1988 to 1959, the area of Jezila irrigation area reached 420000 square meters.
After the independence of Sudan, Manjir irrigation area was opened in Xiyou of Jezila irrigation area.It was completed in five stages from 1957 to 1963, with a total irrigation area of 250000 square meters.In order to meet the agricultural water demand of new irrigation areas, it was built in the upstream of Sennar Dam from 1960 to 1966scaleThe larger Roseires Dam has an initial dam height of 57m.The storage capacity reached 2 billion cubic meters, then increased to 68 meters, and the storage capacity increased to 7.4 billion cubic meters, with an irrigation area of 553 square meters.
In 1964, the Sudan also built the Hashmgirba dam on the Atbara River, and opened a new gravity irrigation area to settle the damAswan High Dam50000 Sudanese living in the reservoir.The reservoir has a storage capacity of 1.3 billion cubic meters, and can irrigate 210000 square meters of farmland. The first phase was completed in the 1960s, and the irrigation area has reached 50000 square meters.
The above gravity irrigation areas are all equipped with supporting irrigation systems, with vertical and horizontal canals in order.For example, the main irrigation area of Jezila and the sub irrigation area of Manjir each have a main canal of 4m with a flow of 168m ³/s;Mangier main canal is 50m wide, 4m deep and 186m ³/s.The two main canals supply water to several main canals respectively, and each main canal also supplies water to a branch canal. The total area of the two major irrigation areas, Jemyra and Manjir, exceeds 800000 square meters. Due to strict management, stable output and low irrigation cost, they have become an example of developing large-scale artesian irrigation agriculture in Africa.
During this period, countries in the Nile basin built a series of projects, mainly for irrigation, but some projects also have certain power generation benefits.
However, the reservoirs built in this period are all regulating reservoirs within the year. In order to prevent sediment deposition, the operation mode of discharging muddy water and storing clean water is generally adopted, and only part of the remaining water in the flood period of the year can be stored to supplement the shortage in the dry season of the next year. Despite this, the sediment deposition in the reservoir is still increasing year by year, and the flood storage capacity is getting worse. Once encountering a dry year, the above reservoirs appear powerless.
In addition, at this stage, the rise of modern irrigation agriculture in Sudan has affected Egypt's summer irrigation water.For this reason, Egypt signed the Nile Water Agreement with Britain in 1929, which strictly restricted the water consumption of Sudan's Jezila Farm and the storage time of Sennar Reservoir. Egypt accounted for 48 billion cubic meters, and Sudan could account for 4 billion cubic meters (all calculated in Aswan).This shows that Egypt and Sudan began to have water conflicts.
In order to fully develop and utilize the Nile water resources, Egypt and Sudan signed a new Nile Water Agreement in November 1959.The agreement recognizes the vested interests of Egypt and Sudan;Agree to build Aswan High Dam in Egypt. The annual net benefit of the high dam is 22 billion cubic meters, Egypt is 7.5 billion cubic meters, and Sudan is 14.5 billion cubic meters. Thus, the shares of Egypt and Sudan will increase to 55.5 billion cubic meters and 18.5 billion cubic meters respectively;In addition, the two countries also agreed to build marshes in SudanWater diversionThe project will thus increase the water volume of the Nile. The costs and benefits will be shared equally between the two countries, and a permanent joint technical committee will be established to supervise the implementation.The new agreement reflects the international cooperation in the development and utilization of Nile water resources.
Late 1960s
This period is characterized by the construction of Aswan High Dam, the start of multi-year regulation of runoff, the improvement of water use assurance rate in dry years, and the comprehensive utilization of the river has begun to take shape.
As mentioned earlier, the NileInterannual change of water resourcesIt is very large, which can be divided into high flow years and low flow years. The maximum annual runoff was 151 billion cubic meters, while the minimum annual runoff was only 42 billion cubic meters. There is a wide gap. In some years, a large amount of river water was discharged into the sea without use, and in some years, it was far from enough for irrigation. The only way to solve the above contradiction is to build a multi-year regulation reservoir in the Nile,It can store the surplus water in the wet year for the dry year.
the Nile
Countries in the Nile basin have studied the "Century Water Storage Plan" and planned to build a series of water storage projects on the upper reaches of the Nile.The plan mainly includes the following projects: ① constructionMobutu LakeMulti year regulation reservoir to regulate runoff together with Lake Victoria Reservoir; ②The Qionglai Canal bypassing the Zhaoze area of Soviet Germany was built to reduce evaporation loss; ③buildLake TanaMulti-year reservoir; ④Build an annual regulation reservoir (the fourth waterfall dam) on the main stream of the Nile between Atbara and Wadihalefa.This plan has been compared with the plan of building Aswan High Dam.Because the former was too large, took a long time to realize and was not adopted for other reasons, it was decided to build Aswan High Dam first.The dam was started on January 9, 1960. The dam was basically completed in 1967, and the project was completed in 1970.In order to irrigate all the year round, people built several barrages on the Nile in the 19th century.1970Aswan DamIt was completed from 1959 to 1970. It took 11 years and cost US $1 billion to build the world-famous Aswan High Dam.Aswan High Dam controls the annual flood of the Nile, protects residents and crops, and can also provide a large amount of power.Aswan High Dam is located near Aswan, Egypt.It is a rockfill dam.The dam is 111 meters high, 3830 meters long at the top, and 44.3 million cubic meters in volume（Nasser Reservoir）The capacity is 168.9 billion cubic meters.After the completion of the reservoir, more than 320000 hectares of irrigation area will be increased, and 280000 hectares ofFlood plainTransformed into perennial irrigation area.Egypt and Sudan agreed to share the Nile water (with an annual total of about 74 billion cubic meters) between the two countries, of which 55.5 billion goes to Egypt.In order to build the reservoir, the ancient temple of Abu Simbel was relocated, with a population of 140000.A new agricultural area has been formed.The high dam has brought great benefits to Egypt.
The Aswan High Dam was built in the Sade Al Ali Valley, 7 kilometers upstream of the old dam, 800 kilometers south of Cairo.The maximum dam height is 111 meters, the total reservoir capacity is 168.9 billion cubic meters, and the effective reservoir capacity is 90 billion cubic meters.Reservoir backwaterIt is 500 kilometers long, about 300 kilometers long in Egypt, called Nasser Lake, and about 200 kilometers long in Sudan, calledNubiaLake.The average width of the reservoir is 10km.There are 12 hydropower stations with a total installed capacity of 2.1 million kW and an annual generating capacity of 10 billion kW · h.After the completion of the high dam, the seasonal fluctuation of the Nile water level has been effectively eliminated.In addition to the average evaporation and leakage losses of 10 billion cubic meters, the Nile can provide 74 billion cubic meters of stable water for Egypt and Sudan every year, 22 billion cubic meters more than before the dam was built.
The economic benefits brought by the high dam to Egypt are in many aspects, specifically as follows: ① It ensures the need for irrigation water, which can be expandedCultivated land550000 square meters, andUpper EgyptThe remaining 380000 square meters of cultivated land has been irrigated all year round instead of embankment irrigation.The summer planting index of factory cultivated land was increased to increase Egypt's agricultural production by 25%, and the agriculture was saved in the extremely dry season from 1972 to 1973 and 1980 to 1987. ②Flood control and eliminationflood。After the completion of the dam, Egypt has overcome three major floods in 1964, 1967 and 1975. ③High dams will be built into large hydropower stations in Africa, providing Egypt with cheap electricity, thus reducing the fuel consumption of thermal power stations. ④Improve the shipping conditions to increase the freight volume of the Nile (Egypt section) to 10 million tons. ③Reduce the dredging work of downstream irrigation channels and save dredging costs. ⑥Lake Nasser It has developed into a large freshwater fishing ground, with the catch increasing year by year, and the fishery resources have great potential. ⑦Tourism in Aswan has been developed, increasing government revenue. ⑧Promote urban prosperity and increase employment opportunities.
Egypt drew up a land reclamation plan from 1960 to 1980 by taking advantage of the increased water content of the Nile River due to high dams.There are 12 plans, 7 of which are around the Lower Egypt Delta andSinai PeninsulaThe other five are in the Nile Valley of Upper Egypt.A total of 52.5 square meters of cultivated land is planned to be expanded. By 1980, Egypt had reclaimed 470000 square meters of land using the newly added Nile water.In addition, since the 1960s, Egypt has changed 320000 square meters of cultivated land in the Nile Valley of Upper Egypt from seasonal irrigation to perennial irrigation by expanding irrigation canals and building pumping stations in two stages.
On the other hand, the high dam also has a series of impacts on the ecological environment and society to varying degrees: ① 130000 people have been relocated and resettled from the reservoir area, and the resettlement investment accounts for 25% of the total investment. ②Sediment deposition in the reservoir not only makes the downstream lose the annual natural fertilizer source, but also causes the downstream riverbed to brush deep. ③Destroy the balance of erosion and deposition on the northern edge of the delta, causing erosion and retreat of the Nile Delta. ④The decrease of discharged fresh water leads to the change of water quality in the delta area.The sea water flows backward, and the sardines production outside the Nile estuary is seriously reduced. ⑤The expansion of perennial irrigation area leads to the delta areasecondary salinization of soil The incidence of schistosomiasis increased.
Of course, the construction of the high dam is based on the needs of Egypt's national economy. Although the total cost is up to 590 million Egyptian poundsEconomic benefitsBut more than 230 million Egyptian pounds.Since the completion and operation of the high dam, the accumulated income has already exceeded the investment and loss.Comprehensively measured, the advantages outweigh the disadvantages and the gains outweigh the losses.
During this period, Sudan continued to devote itself to the development and utilization of Nile water resources.In the 1970s, priority was still given to the development of irrigation and hydropower to increase the use of water in the Nile.Large projects are mainly to build Rahad and Kenana irrigation areas.
Rahad irrigation area is located on the bank of Rahad River in the southeast of Jzila irrigation area. It is 160 kilometers long from north to south, 15 to 25 kilometers wide from east to west, with a total area of 3160 square kilometers, and can reclaim 270000 square kilometers of land.The irrigation area uses the Blue Nile River of the Rahad River, and adopts the combination of water lifting irrigation and gravity flow irrigation for irrigation.In 1973, a dam was built in Rahad for flood storage.As the river is seasonal and the riverbed is dry in dry season, the reservoir water storage cannot meet the irrigation needs in dry season. Therefore, the largest electric pump station in Africa will be built in Mira on the bank of the Blue Nile to pump the Blue Nile water and send it to the irrigation area through a trunk canal 84 kilometers long and 2.5 meters deep.In addition, the project also includes the construction of 10 major bridges, 108 medium and small bridges, 9 flood discharge stations and 52 irrigation gates.
Kenana Irrigation Area is located about 300 kilometers south of Khartoum.The vast tropical scrub grassland between the blue and white Nile is planned toRoseires ReservoirStart construction along the west bank of the Blue NilecanalDevelop artesian irrigation and reclaim 500000 square meters of land.utilizeWhite NileWater is pumped for irrigation.The project includes the construction of four large water pump stations, 29 km main canals, 279 km branch canals and 500 water distribution structures.The water lifting elevation is 40m, and the diversion flow of the main channel is 4.2m ³/s.
Ethiopia, located in the upstream of the seasonal high water area, continues to develop the green NileWater resources。In 1973, Fenqia Dam was built at the branch of the Blue Nile River in Vorega Province, with an installed capacity of 100000 kW and the maximum annual power generation of 532 million kW · h.
In addition, Tanzania, which is located in the annual high water area of the East African Plateau, built the Nikkada Hydropower Station in Mwanza on the south bank of Victoria in 1978, with a power generation capacity of 18000kW.
So far, there have been 7 large sluices and 10 dams in the Nile basin, with an installed hydropower capacity of 2.901 million kW, and an irrigation area of 4.548 million square meters in the whole basin, includingCultivated land area4468000 square meters.
Since 1980s
The characteristics of this period are: while continuing to build multi-year regulation reservoirs, measures such as water increase, water conservation and water saving are taken to improve the utilization rate of water resources and comprehensively utilize rivers.
(1) The contradiction between supply and demand.With the economic development of countries in the Nile basin, the demand for Nile water is gradually increasing, and the contradiction of water shortage is becoming increasingly serious.
Egypt is located in the desert water loss area, and the Nile water is the lifeblood of Egypt's economy.For more than a century, the cultivated area and planting area of Egypt have been expanding, but still can not catch upentranceAs a result of the growth rate, the per capita cultivated area and planting area have decreased year by year, and this trend will continue.The lack of arable land and food is the top priority in Egypt;It has always been Egypt's established national policy to develop water resources and expand arable land.The amount of Nile water provided by Aswan High Dam for Egypt can no longer meet the needs of further economic development, and the tension of water resources is deepening.Therefore, the protection and development of Nile water resources has become one of the important factors for Egypt to formulate economic policies.
Sudan has superior natural conditions and rich water and soil resources.The Nile River flows through Sudan for about 3300 kilometers, almost half of its total length. Almost all major tributaries converge in Sudan. The land is vast, with arable area of 84 million square meters and less than 10 million square meters of arable land,Agricultural production potentialVery big.Sudan's economy has always been based on agriculture, focusing on developing irrigation and increasing arable land.Irrigation water use has increased sharply, and the contradiction between supply and demand of water resources has become increasingly acute.It is also necessary to expand water sources and increase the water content of the Nile.
Ethiopia is located in the upstream of the seasonal water rich area, but it is seasonally short of water. According to the climate conditions, most regions of the country can plant crops all the year round. On the plateau, crops can be harvested twice a year, and agriculture can even be harvested three times a year. However, due to underdeveloped irrigation, there are few replanting.The limited irrigation area is mainly concentrated inAwash RiverRiver basin and Eritrea (now independent), the Nile basin is almost blank.In 1978, Ethiopia decided to set up a project in the tributaries of Atbara River, Tekeze River and Blue Nile RiverDinder RiverBuild dams to block water and develop irrigation to changesoil erosionWater shortage in dry season.Ethiopia, which did not sign the Nile Water Agreement in the past, urgently wants to share the Nile water, which further increases the tension of water resources.
In addition, some countries located in the annual high water area of the East African Plateau have also drawn up plans to reclaim marshes and develop irrigation.asUgandaPrepare to reclaim the marshes in the south of Kioga Lake to plant rice;Kenya intends to reclaim landLake VictoriaNearby Yarra River swamp;TanzaniaIt is proposed to develop water pumping irrigation on the shore of Lake Victoria to expand the area of cotton and rice planting, and alsoRwanda、burundiCooperative development in UgandaKagera RiverSwamp, develop agriculture.
The water resources of the Nile River are not only concerned by most basin countries, but also by countries outside the basin, and the supply is in short supply.
(2) Main measures to increase income and reduce expenditure.
The key to tap the potential of Nile water resources is to reduce the evaporation loss of river water, including the evaporation of lake, river, reservoir and marsh.It is more feasible to reduce the evaporation loss of marshes, especially the evaporation loss of large marshes in Sudan.
The Qionglai Canal plan aimed at reducing the water loss of the Jebel River in the Sud Marsh has been implemented after several modifications.The project was completed in July 1976 byFranceContracted by International Construction Company, the giant bucket wheel excavator is used for construction.Starting from Boer, 70km to the south of Qionglai, the canal is 350km long, 46-52m wide at the bottom, 4.5m deep, and 1:2 slope. The total excavated earthwork is 87 million cubic meters, and the diversion capacity is 830m ³/s, which is equivalent to one fourth of the average flow of the Jebel River in Mongla.The canal broke ground in June 1978.In addition to the excavation of the canal, the canal is also built at both endsControl sluiceTo control the water inflow and outflow.After the completion of the diversion canal, the annual runoff of the Nile in Malakal will increase by 4.7 billion cubic meters due to the reduction of evaporation loss in the marsh area, which is equivalent to the annual net increase of 3.8 billion cubic meters in Aswan, shared equally by Egypt and Sudan.
Once the above marsh water diversion plan is realized, a total of 20 billion cubic meters of water can be added every year, with great development potential.
Although the implementation of the "Century Water Storage Plan" has been delayed due to the yield of the Aswan High Dam Project, the realization of the water diversion project in the marsh area is actually the start of the "Century Water Storage Plan", which is a necessary major measure to further fully utilize the Nile water resources.
Since the Century Water Storage Project can control the annual water volume in the high water area of the East African Plateau and adjust it for many years, it will provide stable and reliable natural runoff for the downstream after completion, so as to ensure the full use of the swamp diversion canal;On the other hand, only by making full use of the marsh diversion canal can the century water storage project have practical significance.
In addition to marshes, the annual evaporation water consumption of reservoirs and lakes is very considerable.Once the potential of the marsh area is exhausted, it can be predicted that the next goal is probably to reduce the evaporation loss of reservoirs and lakes to increase the water volume of the Nile.
In addition to the above measures, other measures include improving irrigation technology, saving water, increasing water reuse, etc.For example, Egypt must continue to expand its arable land to increase food production due to the huge pressure of increasing imports.However, the potential of Nile water resources in Egypt has almost been exhausted.For how to solve the problem of domestic water use, the following countermeasures have been taken: first, actively expand the use of water resources other than Nile water;The second is to improve irrigation technology, save water, strengthen the management and protection of water resources, effectively use cultivated land and follow the path of intensive cultivation.Measures taken in this regard include: improvementdrainage system, open drainage is changed to concealed pipe drainage;Improve the reuse rate of river water;Develop water lifting irrigation, sprinkler irrigation and drip irrigation.
(3) Pay attention to environmental and ecological issues.
With the increase of entrance and economic development, the development and utilization level of Nile water resources in various countries in the basin has been continuously improved, and the impact of human activities on the geographical environment of the basin has become greater and greater, and the resulting cattle environmental problems have become more and more important.This is particularly prominent in Egypt, which has the longest and deepest history of development and utilization.
For more than a century, Egypt's irrigation area has been expanding all year round: because of long-term water transmission through channels, irrigation water has infiltrated, and the groundwater level has risen significantly, leading to swamping and secondary salinization of the upper soil in the delta region, fertility decline, and affecting crop yield.This is an example of the degradation of agricultural cattle environment caused by the development and utilization of the Nile water resources. For this reason, Egypt has taken corresponding remediation measures:Farmland capital constructionStrengthen field drainage, promote water lifting irrigation and control agricultural water use.These measures not only save valuable irrigation water, but also inhibit the development of soil secondary salinization to a certain extent, so as to protect the agricultural cattle environment.
The completion and operation of Aswan High Dam has brought huge economic benefits to Egypt, but the project has also produced a series of side effects on the environment and society of Egypt, which fully shows that the construction of large-scale water conservancy projects should not only considerTechnical and economic effectsAt the same time, the adverse impact of the project on the environment must also be taken into account. The environmental impact of the water conservancy project should be correctly judged and evaluated in advance, and it is crucial for further development of the Nile water resources in the future to balance the advantages and disadvantages and take precautions.
SudanQionglai CanalThe above problems also exist. The economic benefits of the project are very obvious, and the environmental impact can not be ignored.After the construction of the project, the original hydrology of the marsh area has changed, which has a long-term impact on fisheries, aquatic organisms, etc., changes the relative proportion and area of the marsh area, and affects the nomadic life of local tribes.Therefore, the large-scale canal project still needs to make corresponding assessment on its environmental and social impacts before its completion, and take effective regulation measures to make the canal have good technical, economic and environmental quality effects.
Ethiopia has small forest land area and low forest coverage,rainfall intensity andRiverbed gradientBoth of them are very large. In addition, excessive logging has led to serious water and soil loss. Therefore, in the future, water and soil conservation must be paid attention to in the development of the Blue Nile and Atbara River basins and in the development of irrigated agriculture. Neither development nor regulation can be neglected.
(4) Strengthen international cooperation, unified planning, joint development and rational distribution of water resources.The Nile is an international river. With the increase of water consumption in the basin countries, the allocation of water resources has gradually become an international political issue.Therefore, the countries in the basin should strengthen international cooperation and jointly develop water resources in a reasonable manner based on the principle of equality and mutual benefit.In addition, the Nile Basin is a region that involves many countriesGeographical unitThere should be a unified plan for the development and utilization of river basin water resources.From the overall development trend, although there are many contradictions and difficulties, the countries in the basin have already set a precedent for reasonable allocation of water resources through consultation. As long as further consultation and cooperation are strengthened in the future, the existing contradictions are expected to be resolved.
historical significance
Announce
edit
The Nile Basin is one of the birthplaces of world civilization. The people of this region have created brilliant culture and made outstanding contributions in the long history of scientific development.The outstanding representative is ancient Egypt.Although only 1350km long (6671km long), the Nile River flowing through Egypt has the best natural conditions, with an average width of 800-1000m, depth of 10-12m and gentle flow.When it comes to the cultural heritage of ancient Egypt, people first think of thePyramid, the abundant papyrus in the Nile, the ancient boats and the mysteriousmummy。They marked the height of science and technology in ancient Egypt, and recorded and carried forward the development of civilization for thousands of years.
The papyrus is a kind of plant that looks like a reed and is abundant inNile Delta。The stem is triangular, about five meters high, and 6-8 cm in diameter near the root.When using, first peel off the bark of the papyrus stem, use a knife to cut long strips along the growth direction, and place them horizontally and vertically, hit them with a mallet to make the juice seep out. After drying, these strips will be permanently stuck together, and finally polished with pumice, which can be used, becoming the most advanced writing carrier at that time -Papyrus , compared with ChinaCai LunIt is more than 1000 years ago and has become an important document for later scholars to study the ancient Egyptian civilization.However, since the papyrus is not suitable for folding and cannot be made into books, it is necessary to stick many papyrus pieces into long strips and roll them into a scroll after writing.
An ancient ship about 4700 BC unearthed in Egypt, with a length of nearly 50 meters and complete equipment, shows the original navigation technology and scale.The lighter boats are tied with reeds.Don't underestimate this reed boat. The reed boat copied by modern people has proved that it can crossAtlantic。These undoubtedly played a vital role in the social prosperity and civilization of ancient Egypt moving towards the world.
The Nile also makes the local people have unparalleled artistic imagination.How rugged the magnificent temple located on the arid land of East Africa is, in sharp contrast to the winding Nile beside it.Many works of art in ancient Egypt are both masculine and feminine.
According to legend, the goddess Izs loved her husband dearly. One day, her husband died. Izs was overwhelmed with grief and burst into tears. Tears fell into the Nile, causing the river to surge and flood.Every year on June 17 or 18, Egyptians hold a grand celebration for this, called "Tearing Night".From this fairy tale, we can easily see people's deep feelings for the Nile.
The Nile, the cradle of Egypt
Announce
edit
The stable and lasting Nile civilization isAncient Egyptian Civilization, produced in about 3000 BC.Egypt is located inAfro-AsiaAt the border of the mainlandSumerianIn the course of trade exchanges, they were deeply encouraged and formed a civilization with their own characteristics.
The Nile Valley AndTwo river basinDifferent. To the west is the Libyan desert, to the east is the Arabian desert, and to the south isNubian DesertAnd the cascading waterfall. To the north is the coast without harbor in the delta area.In the embrace of these natural barriers,Ancient EgyptiansCan live safely without sufferingbarbarian tribesThe fear and suffering brought by the invasion.
Egypt, as a gift of the Nile, is flooded with Nile water every year, which covers the valley with a thick layer of silt, making the valley area extremely fertile and the crops can be harvested three times a year.According to the records of Dodd in Greece, "the farmers there only need to wait for the river to flood out on its own, flow to the fields for irrigation, and then return to the river bed after irrigation. Then everyone will scatter the seeds on their own land, ask the pigs to step into these seeds, and then they will just wait for the harvest." Indeed, it is the Nile that makes the agriculture in the lower reaches rise and become a famous granary in ancient times.stayAncient EgyptAgriculture has always been the most important socio-economic foundation.Under such advantaged natural environment and conditions, the history of ancient Egypt is relatively simple.From about 332 BC,Alexander the GreatUp to the conquest of Egypt, it had experienced 31 dynasties.Although there were internal turmoil and brief foreign invasion during the period, the political situation was generally stable.
Ancient Egyptian characters were originally simpleHieroglyphicsAfter a long period of evolution, a compound hieroglyphics system composed of letters, notes and phrases was formed.Now we can see that ancient Egypt and characters are mostly carved inPyramid、obelisk, temple walls, coffins and other sacred places.Papyrus papyrus, a plant abundant in Egypt, can be used for writing by cutting its stem into thin strips, pressing them flat and drying.suchPapyrus documentA few have been handed down to this day.
The letters appeared between 2500 BC and 1500 BC.The great progress of turning sounds into letters was accomplished by the ancient Egyptians.These letters were passed from the Egyptians tomediterranean seaEast bank (todaySyriaPhoenicians in China).AsAsiaCultural and European cultural intermediaryPhoenicians, turn these letters into real phonetic characters, and transmit them toancient Greek。This alphabet, afterGreekThe addition of vowels further completes the formation of Greek letters.After some improvements, the Greek alphabet spread all over the country.Letters are the important cultural heritage left by the ancient Egyptians to the western civilization and even the world civilization.
Ancient EgyptastronomyAnd mathematicsMesopotamian civilization Comparable.They created the earliestSolar calendar, set a year as 365 days.The common Gregorian calendar in the world derives from this.The ancient Egyptians adopted the decimal notation very early, but they still didn't have the concept of "zero".Their arithmetic is mainly addition and subtraction, multiplication and division into addition and subtraction.The most distinctive feature of Egyptian arithmetic is that it has preliminarily mastered the concept of fraction.staygeometryOn the one hand, Egyptians have known the calculation method of circular area, but they have no concept of pi.They can also calculate the areas of rectangles, triangles and trapezoids, as well as the volumes of cubes, boxes and columns.
Medical achievement ratio in EgyptMesopotamiaProminent.Egyptianmummy(specially treated air dried corpses), and theirPyramidSame, world-famous.Making mummies increased the Egyptians' knowledge of anatomy, thus making their internal and external medicine quite developed.Their division of medical skills is very detailed. It is said that each doctor only treats one disease.
The most important spiritual life of the ancient Egyptians was religion.Care about death and make material preparations for the afterlife (especially the king's afterlife)Egyptian religionA major feature of faith.Mummies and pyramids (tombs) in ancient Egypt are all related to this religious belief.Egyptians worship the sun god. Especially after the Pharaoh's regime was strengthened, Egypt started a movement to worship the sun god.The sun god La, later called Amun La.It is the highest god of Egypt, and the pharaoh (king) is regarded as the incarnation of the sun god.Therefore, the pharaoh is always considered as the god king, and there is no difference between the holy pharaoh and the secular pharaoh.Since Pharaoh is a god king, his power is also deified. His words are laws, so there is no strict legal system in Egypt.The absolute control of the state over economic life is alsoEgyptian civilizationThe salient features of.
Pyramid is a typical representative of Egyptian architectural art, and also the most famous collective labor achievement of Egyptian labor under the control of the state.The pyramid is the tomb of the pharaoh. Its base is square and narrower as it goes up. As for the top of the pyramid, it becomes a spire, similar to the Chinese character "Jin", so it is translated into a pyramid in Chinese.In the languages of European countries, it is often called "Piramis" (such as Pyramid in English). It is said that in ancient Egyptian, "Piramis" means "high".There are 70-80 pyramids in Egypt, and the most familiar one is the west bank of the lower reaches of the Nile,GizaThe pyramids around here are far from the capital of EgyptCairoOnly more than 10 kilometers.The largest pharaoh of the Fourth DynastyKhufu(reigned from about 2590 BC to 2568 BC)Seven Wonders of the WorldThe only existingHistorical Site。
In addition to the pyramidsTemple、palaceSuch buildings are also quite magnificent.By contrast,EgyptThe figures and statues in Egypt are stiff and indifferent, and the mummy culture in Egypt is difficult for outsiders to understand.In a word, the Egyptian culture is characterized by the unity of God and King, the pursuit of eternity, which is relatively simple, stable and conservative.Relatively speaking, the life of the Egyptian people is mediocre and satisfied.In contrast, the technology of Egyptian craftsmen in manufacturing luxury goods is universally recognized.The Egyptians were the first to invent beauty products and developed the technology of making beauty products.
Resource dispute
Announce
edit
With the population growth and industrial and agricultural development of the countries in the Nile basin, the demand for water is increasing day by day.However, the distribution of Nile water is still based on the agreement decades ago.
In 1929, in Britain at that timeColonistUnder the proposal ofSudanThe agreement on the priority to use the Nile water,EthiopiaYou have not joined this agreement.In 1959, countries in the Nile basin made some amendments to the agreement. Egypt enjoyed 55.5 billion cubic meters of Nile water every year, while Sudan's share was 18.5 billion cubic meters. Other countries believed that the agreement was unfair.
Was once calledAfricaEthiopia, the "water tower", is guarding the source of the Blue Nile. The amount of water flowing into the Nile from Ethiopia every year accounts for 86% of the total water volume of the Nile. Therefore, Ethiopia requires at least 12 billion cubic meters of river water each year.Egypt and Sudan do not agree with Ethiopia to intercept the river from the upstream, believing that this will affect the survival of the downstream.Due to serious water shortage, the former president of EgyptSadat Once said: "Egypt will respond strongly to any action that may endanger the flow of the Blue Nile, even if resorting to war."
Longest dispute
Announce
edit
The longest river: the Nile,AmazonDisputed.With a length of 6695km, the Nile is recognized as the longest river in the worldPeruAfter a long journey, the scientific research team formed by the two countries found a new source of the Amazon River, which made the Amazon River 6800km long, becoming the longest river, but caused controversy among experts.U.S.AThe geographical survey satellite has confirmedworldThe first long river isAmazon。
So far, the length of the Amazon River measured by different geographers is 6259 and 6800 kilometers (3889 and 4225 kilometersmile）Between.Generally speaking,Amazon"At least" is 6400 kilometers (4000 miles) long.The total length of the river is 6670 kilometers, and the drainage area is 2.87 million square kilometers.[1]
In 2007, a field expedition conducted by Brazilian scientists concluded that the Amazon River is actually 65 kilometers longer than the Nile River.National Bureau of Geography and Statistics(IBGE) recalculated the length of the Amazon River from satellite images in 2008.They used the source demarcated by Brazilian scientists in 2007 to calculate the length of the Amazon River, which is 6992 kilometers (4345 miles) long.Using the same technique, the Nile is 6853 km (4258 miles) long, although longer than previously estimated, it is still shorter than the Amazon.
However, there are many factors that can affect the measurement results, such as the determination of the start and end points of rivers.
