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Description
The Yellow River or Huang He / Hwang Ho is the second-longest river in China and the sixth-longest in the world at 5,464 kilometers . Originating in the Bayan Har Mountains in Qinghai Province in western China, it flows through nine provinces of China and empties into the Bohai Sea. The Yellow River basin has an east-west extent of 1900 km and a north-south extent of 1100 km . Total basin area is 742,443 km²
The Yellow River is called "the cradle of Chinese civilization", as its basin is the birthplace of the northern Chinese civilizations and was the most prosperous region in early Chinese history. But frequent devastating flooding largely due to the elevated river bed in its lower course, has also earned it the unenviable name "China's Sorrow".
Early Chinese literature refers to the Yellow River simply as "River". The first appearance of the name "Yellow River" is in the Book of Han written in the Western Han dynasty (206 BC–AD 9). The name "Yellow River" describes the perennial ochre-yellow colour of the muddy water in the lower course of the river. The yellow color comes from loess suspended in the water.
History
The river is extremely prone to flooding. It has flooded 1,593 times in the last 3,000–4,000 years, while its main course changed 12 times, with at least 5 large-scale changesfrom 602 BC to present. These course changes are due to the large amount of loess carried by the river and continuously deposited along the bottom of the river's canal. This sedimentation causes a natural dam to slowly accrue. Eventually, the enormous amount of waters have to find a new way to the sea, causing a flood in a new valley.
A major course change in 1194 took over the Huai River drainage system throughout the next 700 years. The mud in the Yellow River literally blocked the mouth of the Huai River and left thousands homeless. The Yellow River adopted its present course in 1897 after the latest course change occurred in 1855. Currently, the Yellow River flows through Jinan, capital of the Shandong province, and ends in the Bohai Sea, yet the eastern terminus for the Yellow River has oscillated from points north and south of the Shandong Peninsula in its many dramatic shifts over time.
The course of the river has changed back and forth between the route of the Huai River and the original route of the Yellow River several times over the past 700 years. The consequent buildup of silt deposits was so heavy that the Huai River was unable to flow in its historic course after the Yellow River reverted to its northerly course for the last time in 1897. Instead, the water pools up into Hongze Lake and then runs southward toward the Yangtze River.
Floods on the river account for some of the deadliest natural disasters ever recorded. The flatness of North China Plain contributes to the deadliness of the floods. A slight rise in water level means a large portion of land is completely covered in water. When a flood occurs, a portion of the population initially dies from drowning, then by the spread of diseases and the ensuing famine.The 1887 Yellow River flood in the North China Plain caused an estimated 900,000 to 2,000,000 deaths.
Uses of Yellow River :
• Transportation
• Sightseeing/Tourist Attraction
• Irrigation
• Hydroelectric Dam
• Fertile alluvial soil
Transportation
People can use the boat to travel from one place to another .
Sightseeing/Tourist Attraction
Famous rivers are popular tourist attraction. Tourist comes to see the spectacular view of the various landforms in the river.
Irrigation
Irrigation has been practiced throughout the world. There are modern ways to obtain water from the river as well as traditional ways. Irrigation is very important to areas where there is long period of drought, areas with seasonal rainfall. Irrigation has helped farmers to have double or even up to triple cropping per year.
Hydro-electric power
Dams are often builds across rivers to tap on the river energy to generate hydroelectric power. Hydroelectric power plants convert the kinetic energy contained in falling water into electricity. Hydropower is currently the world's largest renewable source of electricity, accounting for 6% of worldwide energy supply or about 15% of the world's electricity. In Canada, hydroelectric power is abundant and supplies 60% of our electrical needs.
Hydroelectric power plants capture the energy released by water falling through a vertical distance, and transform this energy into useful electricity. In general, falling water is channeled through a turbine, which converts the water's energy into mechanical power. The rotation of the water turbines is transferred to a generator, which produces electricity. The amount of electricity, which can be generated at a hydroelectric plant, is dependent upon two factors. These factors are (1) the vertical distance through which the water falls, called the "head", and (2) the flow rate, measured as volume per unit time.
Fertile alluvial soil
Floodplain and delta are good agricultural land, which have fertile alluvial soil. The alluvial is increased when the river floods. The flat and low-lying floodplain and delta makes it easier for people to build settlement and farm. Many urban settlements start in the fertile floodplain. Bangkok in the Menam Chao Phraya Delta of Thailand is one good example.
Sources for picture : http://images.search.yahoo.com/search/images;_ylt=A0S020okpmpKVq8AzqaLuLkF?p=yellow+river&ei=utf-8&iscqry=&fr=sfp
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