The six great lakes of the saltwater lake
Dead Sea-the lowest lake in the world and the highest salinity lake.
Great Salt Lake-the largest saltwater lake in America.
Aier Lake-the largest lake in Australia.
Qinghai Lake-the largest lake in China.
Namco-the highest saltwater lake in the world. geographical position
Located in the abdomen of Eurasia, between Asia and Europe, the east, north and west banks of the lake belong to Turkmenistan, Kazakhstan, Russian Federation and Azerbaijan, and the south bank is in Iran, making it the largest lake and the largest saltwater lake in the world. Basic profile
The Caspian Sea is an out-and-out inland lake, so why is it called "sea"? Judging from the natural characteristics of the Caspian Sea, the Caspian Sea has vast waters, vast smoke waves and endless winds and waves, just like the rolling waves of the sea. At the same time, the water in the Caspian Sea is salty, and many aquatic animals and plants are similar to marine life. In addition, judging from the reasons for the formation of the Caspian Sea, there are Caspian Sea, Aral Sea, Mediterranean Sea, Black Sea and Azov Sea. Originally part of the ancient Mediterranean. After the evolution of land and sea, the ancient Mediterranean gradually narrowed, and the outline, area and depth of the above-mentioned sea areas changed many times. Therefore, today's Caspian Sea is a remnant of the ancient Mediterranean Sea, which geographers call "Sea Trace Lake". Therefore, people call the world's largest lake "Caspian Sea". In fact, it is not a real sea.
The south and southwest of the Caspian Sea are surrounded by the Elbers Mountains and the Caucasus Mountains, and the other two sides are flat plains and lowlands. The Caspian Sea is long and narrow from north to south, slightly "S"-shaped, with a length of about 1, 200 kilometers from north to south. It is the longest and only lake in the world whose length exceeds 1000 km. The east-west average width is about 320km, the coastline is about 7,000km, and the area is 37 1000 km2, which is almost equivalent to the area of the Baltic Sea, 10 times that of the Azov Sea, accounting for 14% of the world's total lake area (2.7 million km2), and 245% more than the total area of the famous Great Lakes in North America. The total volume of this lake is 76,000 cubic kilometers.
ingredient
The Caspian Sea includes Mangeshlak, Kazakhstan, Turkmenistan, Kela-Si Nuo-Wattsk and other bays. The surface of the Caspian Sea is 28 meters below the ocean surface, and the average depth of the lake is about 180 meters. The depth of the Caspian Sea is different, shallow in the north and deep in the south, and the bottom of the Caspian Sea inclines from north to south, which can be roughly divided into three parts: the northern part is generally 4 ~ 6 meters deep; Intermediate water depth 170 ~ 790 meters; The south is the deepest, and the maximum depth can reach1025m. There are about 50 islands in the Caspian Sea, covering an area of about 350 square kilometers. There are more than 130 rivers, such as Volga River, ural river River, Kula River and telek River. From 1940 to 1970, the average annual inflow of fresh water is 2.864 million cubic kilometers, of which Volga River, ural river River and Terek River account for more than 90%.
The whole sea area can be divided into three parts: north, middle and south, separated by many islands and shoals. Beili coastal slope is gentle, and the water depth is very shallow, only 4 ~ 8 meters, and the deepest part is only 25 meters. The seabed is a corrugated sedimentary plain, and the water volume only accounts for 1% of the total water volume. In the Middle Caspian Sea, there are many steep slopes on the coastline of the Great Caucasus Mountains, and the east coast is relatively steep near the Mangeshlak Plateau. The bottom is the shelf in the east and the Gerbat basin in the west, with a water depth of 790 meters; Water accounts for about one third of the Caspian Sea. The South Caspian Sea has a low coast, a broad east-west continental shelf and a depression in the west. It is the deepest part of the Caspian Sea, with a large amount of water, accounting for about two-thirds of the entire Caspian Sea. Seabed sediments and sand containing shells in the North Caspian Sea; There is much mud and sand in the middle Caspian depression, and there are many shells, gravel sand and clay on the east and west coasts. The deep water area of the South Caspian Sea is silt and clay containing thin layers of iron sulfide, and the marginal areas on the east and west banks are sand, lime mud, shells and gravel.
Hydrological characteristics
The current is mainly cyclone circulation, and some local circulation can be formed in each sea area. After entering the sea, the North Caspian Sea and Volga River are divided into two tributaries: the main river flows south along the west bank; The other branch flows eastward along the north shore, forming a small anticyclone circulation in the northeast. The velocity changes with the wind, generally between10 ~15 cm/s. When there is strong northerly wind, the velocity in the west reaches 30 ~ 40 cm/s, and the maximum can reach100 cm/s. The central Caspian Sea is controlled by large cyclone circulation. There is cyclone circulation in the northwest and southeast of the South Caspian Sea. Therefore, a coastal current from north to south is formed in the west of the Caspian Sea, with an average velocity of 25 ~ 35 cm/s, while a coastal current from south to north appears in the east. The average speed is about10 ~15cm/s.
The distribution of water temperature varies with seasons and regions. In winter, there is a great difference in surface water temperature between the north and the south. In February, the temperature in the North Caspian Sea is only 0. 1 ~ 0.5℃, and the temperature in the South Caspian Sea can reach 8 ~ 10℃. In summer, the temperature difference is small, generally 24 ~ 27℃, and the vertical distribution of water temperature also changes with the seasons. In winter, the water temperature in the North Caspian Sea and the Middle Caspian Sea is almost unchanged, and there is a thermocline in the South Caspian Sea at a depth of 50 ~ 100 meters. In summer, the temperature difference between the upper and lower layers at the depth of 30 ~ 50 meters in the central and southern waters is large.
There are 130 rivers flowing into the Caspian Sea, and the annual runoff into the sea is more than 300 cubic kilometers. Among them, the runoff of Volga River into the sea is 256 cubic kilometers, accounting for 85% of the total runoff of Caspian Sea. The discharge into the sea has great seasonal and interannual changes, which directly affects the changes of salinity and water level. Seawater is low in chloride and high in sulfate and carbonate. The salinity of seawater is about two-thirds lower than the standard salinity of seawater. Generally, the south-central part is 12.0 ~ 13.0, and the salinity outside the Volga River Delta is only 0.2. The seasonal variation of salinity is often between 0. 17 and 0.2 1. From February 65438 to April the following year, the North Caspian Sea often freezes. The ice thickness is generally 0.5 ~ 0.6m, with the maximum thickness of1m.. Under the strong north wind, drifting ice can drift south to the vicinity of the Apsheron Peninsula.
The remarkable change of water level in long period and ultra-long period is the most remarkable phenomenon in Caspian Sea. Studies have confirmed that the water level of the Caspian Sea in the early19th century was 22 meters lower than that before 4000 ~ 6000 years. During 7 ~ 1 1 century, there was a low water level. During 1930 ~ 1957, the water level dropped again due to the construction of reservoirs on the Volga River, excessive industrial and agricultural water use and dry climate. Since the early 1970s, the water level of the Caspian Sea has remained at around -28.5 meters. The water level varies greatly in seasons, high in spring and summer and low in winter, with an annual variation of up to 33 cm. The winds in the Caspian Sea significantly increase or decrease the water. In the Volga River Delta, sometimes the wind reduces the water by 4-5 meters, and the wind increases the water by 2 meters.
The water level in the Caspian Sea is the highest in July and the lowest in February. The water level difference in the north is 2-3 meters, and the water level in the south-central part is only 20-50 cm, with the maximum not exceeding 1.5 meters. In summer, the water temperature in the Caspian Sea is basically the same, all around 26℃. In winter, the water temperature in the north is below 0℃. The average temperature in the south is 8 ~ 10, and the shallow water ice age in the north lasts for 2 ~ 3 months every year.
Climatic condition
The sea area spans several different climatic zones. Although the North Caspian Sea has a continental climate, the change is not drastic. The middle Caspian Sea has a mild climate in the west and a dry desert climate in the east. The South Caspian Sea has a subtropical climate and is dry in summer. In winter, the weather in Caspian Sea is unstable and the temperature changes greatly. The average temperature in the north is -8 ~- 10℃, and the average temperature in the south is 8 ~ 10℃. The wind direction is changeable, mainly from the east and northeast. The wind force is 5.5 ~ 10.7 m/s, and sometimes it can reach 20.8 ~ 28.4 m/s in the middle. In summer, the ocean is controlled by high pressure, and there is often a weak sea breeze blowing to the land, so the weather is very stable. The temperature has not changed much. The average temperature in the hottest month is 28 ~ 29℃, the extreme maximum temperature can reach 44℃, and the annual average precipitation is 200 ~ 1700 mm, which is unevenly distributed, with less in the east coast and more in the southwest coast. The annual evaporation is generally 1000mm, reaching 1400mm in the eastern part of the South Caspian Sea and the Apsheron Peninsula.
Caspian Sea is located in desert and semi-desert environment, with dry climate and strong evaporation. According to statistics, the total amount of water flowing into the Caspian Sea every year is 338.2 cubic kilometers, while the annual water consumption is 36 1.3 cubic kilometers. With less inflow and more outflow, there will be a "deficit" that cannot make ends meet, and the water level of the lake will inevitably decline gradually. 1930, with a lake area of 422,000 square kilometers. To 1970, reduced to 37 1 10,000 square kilometers. Because a large amount of water evaporates, salt accumulates year by year, and the lake becomes more and more salty. Due to the shallow lakes in the north, a large amount of fresh water such as Volga River is injected, and the salinity of the lakes in the north is low, 0.2‰, while the salinity of the lakes in the south is as high as 13‰.
Resource situation
The Caspian Sea is rich in oil resources. Baku on both sides of the Taiwan Strait, Mangeshlak Peninsula on the east coast and the bottom of the Caspian Sea are important oil producing areas. Oil production at the bottom of the Caspian Lake has expanded to dozens of kilometers offshore. The ocean is rich in marine substances, including sturgeon, salmon, whitebait and other fish, as well as marine animals such as seals. The Caspian Sea is rich in salt and mirabilite. Karabogazgor Bay is a large mirabilite producing area.
shipping
The shipping industry in the Caspian Sea region is relatively developed. Navigation between the White Sea, the Baltic Sea, the Caspian Sea, the Black Sea and the Azov Sea has been realized through the Volga River and other canals. However, due to the shallow water in the north, shipping is limited. There is a train ferry between Baku and Novotsk, Clasey. The main cargo transported is oil, followed by grain, wood, cotton, salt and building materials. The main coastal ports are Baku in Azerbaijan, astrakhan and Makhachkala in Russian Federation, Chevchenko in Kazakhstan, Novotsk in Clasey in Turkmenistan, Li Enze and tolman in Iran. The lowest lake in the world, with an altitude of -4 18m, is also the lake with the highest salinity. The Dead Sea is an inland salt lake located in the Jordan Valley between Israel and Jordan. The West Bank is the Jewish Mountain, and the East Bank is the Outer Jordan Plateau. The Jordan River flows from the north. Jordan River injects 540 million cubic meters of water into the Dead Sea every year. In addition, four small rivers with water all the year round are injected from the east. Due to the large evaporation in summer and water injection in winter, the water level of the Dead Sea changes seasonally, ranging from 30 to 60 cm.
The Dead Sea is 80km long and18km wide, with a surface area of about1020km2, an average depth of 300m, and the deepest point of 415m. Lisan Peninsula in the east of the lake divides the lake into two lake basins of different sizes, with an area of three quarters in the north and a depth of 4 15m, and an average depth of less than 3m in the south. There is no water outlet, and the water inflow mainly depends on the Jordan River, which is roughly equal to evaporation. It is one of the natural water bodies with the highest salinity in the world.
Because the Dead Sea is located on the disputed border between Jordan and Israel, it has not been used for navigation on a large scale. The lakeshore is barren and there are few long-term settlements. There are only factories in Sedom, several hotels and resorts in Kalia, and a collective farm (Israeli agricultural community) in the Ngedi area in the west. Occasionally you can see a small piece of cultivated land on the shore of the lake. The largest inland salt lake in North America and the largest saltwater lake in the Western Hemisphere. Mount Loki is located in the northwest of Utah, USA, with Mount Loki in the east and desert in the west. Great Salt Lake is the residual lake of great basin Great Freshwater Lake during the Pleistocene Great Ice Age. The dry natural environment of Great Salt Lake is similar to the famous Dead Sea, and the chemical characteristics of lake water are the same as those of seawater. The lake area has changed greatly in history, with an area of 6,200 square kilometers at 1873, only 2,460 square kilometers at 1963, and about 4,000 square kilometers in the early 1970s. The Great Salt Lake extends from northwest to southeast, with a length of 120km, a width of 63km, a depth of 4.6- 15m and an area of 3525km2. The elevation of the lake is about1280m. The salinity is as high as 150-288 ‰. Great Salt Lake is rich in resources, with a large salt reserve of 6 billion tons, of which salt accounts for 3/4, as well as magnesium, potassium, lithium and boron. The Great Salt Lake is the main tourist attraction in Utah. Salt Lake City is the largest city and capital of the state, located on the southeast bank of the lake. The American South Pacific Railway spans the Great Salt Lake.
Located at the Loki Mountains1280m, surrounded by mountains, it is covered with snow all year round. The Great Salt Lake is a stagnant water lake with no outlet. The loss of lake water mainly depends on the natural evaporation of the sun. The recharge of lake water mainly comes from natural rain and melted snow water. When it is hot in midsummer, it is a desert climate, and rain, snow and water constantly wash minerals and trace elements from mountains and deserts into lakes. The sun constantly evaporates the water in the lake every day, and the water is lost, but minerals and trace elements are deposited in the lake. Day after day, year after year, this natural ecological cycle of hundreds of millions of years makes the contents of minerals and trace elements in salt lakes higher and higher, and the concentration of water is 50 times higher than that of seawater.
It is found that the lake water contains 76 kinds of minerals and trace elements, and these elements are consistent with human body fluids, with balanced content and complete types, and have the function of natural sterilization. Even the most difficult bacteria in the world, Salmonella, can't survive. It is by far the most abundant, complete and balanced natural minerals and trace elements in the world.
American MRI Company built several artificial salt drying ponds in the northern part of Great Salt Lake in Utah, and injected lake water with seawater concentration of 10 times, and made crystalline sodium salt by using the hot and high-temperature sunshine in Utah in summer, so that the salt in the lake water was removed by natural forces, and the seawater with seawater concentration of 10 times was concentrated to about 40 times.
Located in northern Utah, USA, the Great Salt Lake is the largest inland saltwater lake in the western hemisphere and one of the inland lakes with the highest salinity in the world. The dry natural environment is similar to the famous Dead Sea. The chemical characteristics of lake water are the same as that of seawater, but the salt content of lake water is much larger than that of seawater because the evaporation far exceeds the recharge of rivers. Historically, due to evaporation and changes in river flow, the lake area has changed greatly. In the mid-1980s, the area of 1.873 and 1.983 was 6,200 square kilometers (2,400 square miles), while that of 1.963 was only 2,460 square kilometers (950 square miles). The maximum height of the lake is 1, 284 meters (42 12 feet) and the minimum height is 1, 277 meters (4 19 1 feet). Generally, the water depth is 4.5m (15ft), and the deepest reaches 1 1 m (35ft).
The Great Salt Lake is a relic of Bonneville Lake in prehistoric times. About 6,543,800 years ago, the area of Lake Bonaville was 52,000 square kilometers (20,000 square miles). In the subsequent ice age, a large amount of fresh water was injected into the lake basin, into the Columbia River through the Snake River, and finally into the Pacific Ocean. After the ice age, the water level dropped and the outlet was cut off, becoming an inland lake. Every year, as many as 65,438+065,438+million tons of salt are imported into the lake basin through the Beier River, the Weber River and the Jordan River. The total salt accumulated in the lake basin has reached 6 billion tons. Mainly sodium chloride, sulfate, magnesium, potassium and so on are also very rich. Salt and potash have been mined since19th century. 197 1 year, magnesium is extracted from lake water on a large scale. The map drawn in18th century has marked the location of the Great Salt Lake. Mormons settle by the lake 1847. The lake area was surveyed at 1850. The first transcontinental railway in the United States was built at 1869, crossing the northeast bank of the lake. 1890, the US Geological Survey conducted a scientific investigation here and obtained a lot of data. Surrounded by large sand dunes, saline-alkali land and swamps, the Great Salt Lake is still isolated from nearby cities and villages. Wildlife reserves protect precious wild birds, such as pelicans, herons, cormorants and terns. The Great Salt Lake will soon become a tourist and leisure resort. Aier Lake-the largest lake in Australia. Lake Eyre is the largest lake in Australia. Located in the northeast of central South Australia, 400 kilometers north of Piri Port. Lake Aier is the lowest place in the Australian mainland, and the lake surface is below sea level15m. Lake Aier is located in the desert of central Australia, which is the lowest side of the Australian mainland. The lake surface is lower than sea level 12 meters. Aier Lake Basin is a large-scale inner lake system near the lake bed, and the lowest point is a shallow salt lake whose water body changes with the seasons. The average annual rainfall in the nearby arid area is less than 120mm, and the annual evaporation is 2,500mm. In the dry season, when the river flows from the mountain to the west, it loses a lot because of evaporation and leakage along the way, and often disappears halfway. The small lake near Aier Lake contains a small amount of water, which often dries up and shrinks into a salt pond. In these two seasons, the river flows into the lake from the northeast, and the two quantities brought by the monsoon determine whether the river will reach Lake Ayr and its depth. The two nearby waters will also flood the lake in a small and medium-sized way, with an average flood of 1.5 meters every three years and 4 meters every 10 year, which will be completely filled four times in a century. After the moderate and small floods at the end of next summer, the lake will be evaporated.
There is no estuary in Aier Lake Basin, which is one of the largest internal flow basins in the world. The main connecting rivers are Cooper Creek and warburton River.
Lake Aier mainly comes from river water and rain. Its area varies greatly, reaching 8200 square kilometers when the rainfall is heavy. When the precipitation decreases, it will dry up. According to its average area, it is the largest lake in the world 19, and according to its largest area, it is the largest lake in Oceania. The largest inland lake in Xizang Autonomous Region, China, is called Tengger Lake in Mongolian, Namu Lake in Tibetan and Tengger Lake in Mongolian all mean Tianhu. To the north of the main peak of Nyainqentanglha Mountain, the lake is 47 18 meters above sea level and covers an area of 1940 square kilometers. The formation and development of lakes are controlled by geological structures, and there are traces of glaciation. The lake has a high salt content, and the basin is rich in wildlife resources, including bison and goats. There are many wild birds in the lake, which produce fine-scaled fish and scaleless fish. The lake is clear, with beautiful scenery against the surrounding snow-capped mountains.
Five islands in the lake stand in the blue water. Buddhists say they are the embodiment of Five Dhyani Buddhas. Anyone who goes to worship the Buddha in Shenhu will pay homage to him.
Namco is a huge Xiao basin formed by Himalayan movement depression. The existing lakeside plain is a natural grassland with good pasture. Every early summer, flocks of wild ducks fly to live and breed. The beautiful and rich Qinghai Lake is the largest saltwater lake in China. Also known as Kukunod and Tsobo, it was called Xihai, Danshui and Tsobo in ancient times. Ku North Mongolian means blue ocean. Qinghai got its name from the Northern Wei Dynasty, because the lake is clear and blue, and the lake is as wide as the sea. Qinghai Lake, located in the Qinghai Lake Basin in the east of Qinghai Province, is the largest saltwater lake in China. The lake looks like a pear.
Qinghai Lake is located in the northeast of Qinghai Province. It's huge and magnificent. It is a magnificent treasure given by nature to the Qinghai-Tibet Plateau and the origin and symbol of the name of Qinghai Province. Qinghai Lake is located in the Qinghai-Tibet Plateau, with a vast territory, vast grasslands, numerous rivers and lush aquatic plants. The lake is surrounded by four high mountains: the majestic Datong Mountain in the north, the majestic Sun and Moon Mountain in the east, the winding Nanshan Mountain in Qinghai in the south and the majestic Rubber Mountain in the west. Looking around, the four mountains are like four natural barriers. From the foot of the mountain to the lake, there is an endless grassland of Senecio, and the rippling Qinghai Lake is like a huge jade plate embedded between mountains and grasslands, forming a colorful western landscape painting.
198 1 year measured water level 3 193.92m, length 109.0km, maximum width 67.0km, average width 39.8km, area 4340km2, maximum water depth 27.0m and average water depth1. Compared with 196 1 year, the lake area has decreased by 295.0km2 and the water storage capacity has decreased by 76.0× 108m3 in recent 20 years. The lake salinity 196 1 year was 12.4g/L, and 1986 increased to 13.84g/L, with an average annual increase of 52.0mg/L in 26 years, showing an obvious salinization trend. The formation and change of Qinghai Lake is a masterpiece of nature. As early as 230 million years ago, the Qinghai-Tibet Plateau was a vast ancient ocean. Two million years ago, the intense orogeny gradually uplifted this ancient ocean, forming the roof of the world. When the sea water was forced away, some of them were surrounded by surrounding mountains, forming lakes of all sizes. Qinghai Lake is a huge lake separated by mountains. At that time, it was a drainage lake, surrounded by more than 100 rivers, and the lake water flowed into the Yellow River from the east. About 6,543,800 years ago in Quaternary, Sun Moon Mountain in the east of Qinghai Lake rose strongly, blocking the exit of Qinghai Lake. The river that originally flowed eastward from Qinghai Lake was forced to flow westward into Qinghai Lake, forming a rare backward flow river from east to west in China. Qinghai Lake has also become a closed lake where running water can only enter and exit. Because Qinghai Lake is located in the northwest arid climate zone, the evaporation of lake water is greater than the injection of lake water, so the lake water is declining and shrinking gradually. Compared with the initial lake surface, the lake surface area is reduced by one third, and the water level is reduced by 80-100 m. 1500 years ago, during the Northern Wei Dynasty, the lake was surrounded for a week, which was called a thousand miles. It was called 800 Li in the Tang Dynasty, but now it is only over 700 Li. Qinghai Lake region belongs to cold and semi-arid climate, with annual average temperature of 65438 0.2℃, 1 month average temperature of-65438 0.2℃, July average temperature of 5℃ and extreme maximum temperature of 28℃. The average annual precipitation is 336.6 mm, and the precipitation from May to September accounts for more than 85% of the annual precipitation, and the annual evaporation is 950 mm. The evaporation from June to September accounts for more than 60% of the annual evaporation. The catchment area of the lake is 296,665,438+0 km2, and the recharge coefficient is 5.83. Lake water mainly depends on surface runoff and precipitation, and there are more than 40 rivers entering the lake. The main rivers entering the lake are Buha River, Bagwulan River and Sidestream River, of which Buha River is the largest. According to relevant data, the total annual water inflow of Qinghai Lake is 36.28× 108m3, while the annual water consumption is as high as 410.59×108m3, and the annual water shortage is 5.3 1× 108m3. This is the main reason why the water level of Qinghai Lake has dropped and the lake surface has shrunk. Qinghai Lake has a vast natural pasture, which is a gathering place for all ethnic groups in China. Besides the Han nationality, there are Qiang, Tuguhun, Tibetan and Mongolian. Since ancient times, it has been an important producing area of animal husbandry, especially bird breeding. During the Spring and Autumn Period and the Warring States Period, "Qin Ma" was abundant in this area. The Book of Songs once described Qin Ma's majesty and kindness. During the Sui and Tang Dynasties, Qin Ma, Wusun Ma and Khan Ma were thoroughbred horses, which were famous for their habit of fighting. Tea and Horse Department was established in Qinghai in the Tang Dynasty. Du Fu's "Protecting Horses in Beijing". "... this horse has fought for a long time and made great achievements with others. ..... Magnificent posture is not affected by Fu Jian Thought, and brave ambition is still thinking about the battlefield. Wrist and hoof are as high as iron, and several rivers are cracked. Five flowers scattered all over the body, Wan Li watched the sweat and snow, and Zhuangzi of Chang 'an dared not ride, and had already walked through the city. "This poem spares no effort to boast about the majesty and divine power of Qinghai horses. The most pristine beauty has real power. Qinghai Lake has the characteristics of broad, rough, simple and quiet plateau lakes. It doesn't have the charm of West Lake, the beauty of East Lake, the splashing sound of Xuanwu Lake and the light and shadow of Kunming Lake ... The beauty of Qinghai Lake is primitive and natural. The scenery of Qinghai Lake is very different in different seasons. In summer and autumn, the lakeside mountains are beautiful with clear water and light clouds, and the scenery is very beautiful. Colorful wild flowers are dotted with grassy grasslands like brocade, and fat cattle, sheep and horses are scattered everywhere like pearls. Qinghai Lake is as blue as the ocean, its blue is pure and deep, and its blue is gentle and elegant. In the cold winter, the grass turned yellow, Qinghai Lake began to freeze, the vast lake was frozen with jade, and a clear nectar solidified into a huge mirror, shining in the sun. Qinghai Lake is famous for producing mandarin fish. Pomfret is a kind of cold water phosphorus-free fish, which is called naked carp. It is a rare fish with tender meat and delicious taste. It is only found in some lakes and rivers on the Qinghai-Tibet Plateau in China. There are five beautiful islands in Qinghai Lake, among which Haixinshan and Bird Island are famous tourist attractions. Haixinshan is about 70 meters higher than the lake, with an area of about 1 square kilometer. The island is rocky, with lush trees and beautiful scenery. The island has been famous for producing dragonflies since ancient times, so it is also called Dragonfly Island. According to historical records, Qinghai Lake "gathers this mountain to be a good horse every winter and comes to Mu Zhi in spring. All the horses are pregnant, and the pony born is called dragon, which will be even more brilliant. "According to legend, when Emperor Ping of Han Dynasty, follwed set up Xihai County by the lake. I used to graze in the mountains, and I got the dragon seed, which traveled thousands of miles every day and was named Qinghai Qi. In the fifth year of Sui Daye, Yang Di went to the Western Ocean and gave lectures to Chen Bing in Qinghai. In July, he set up a horse farm here to raise dragons. No boat can cross Qinghai Lake before. After freezing in winter, herders drove horses and yaks to the island, carrying all kinds of goods for one year, and then went out after freezing in the second year.
The famous Bird Island is a gathering place for birds. Hundreds of thousands of migratory birds come here every year to celebrate the midsummer, which has become a great spectacle of Qinghai Lake. Bird Island, like a tadpole, is located in the northwest corner of the lake, with an area of 0. 1 1 square kilometer. Every summer, geese, fish gulls, brown-headed gulls and cormorants flock from the south, and birds come and go, covering the whole island tightly. In the spawning season, birds nest in a nest, and the whole island is densely packed with eggs. At this time, Bird Island is a jubilant, noisy and busy bird world, and there are busy birds in the sky and underground. Some hold grass, some peck at mud, and some contain hair, which keeps flying from morning till night. After more than 20 days and nights of incubation, the chicks hatched one after another, swaying and chirping behind their parents, and the whole island came to life. When chicks' feathers become more and more abundant, their parents will take them wandering around and foraging. Some went to the nearby Shanpinghu for the summer, and some went to Qingzhiju in the mountain stream, and the bustling Xanadu became silent. In September and1October, the young birds' wings hardened, the Siberian cold current gradually invaded south, and the birds on the island flew south one after another. So year after year, they live a regular and cheerful migration life. Bird Island has also become a famous tourist attraction. Numerous tourists are attracted by the magnificent bird island scenery and unique waterfowl life, and come to experience the tranquility and comfort of bird island paradise and the freshness of nature.