The
largest river in China and the third largest river in
the world, the 6,300-kilometer-long Yangtze River plays
an important role in China. The Yangtze River basin –
with its fertile soil, highly developed agriculture and
abundant mineral deposits – is densely populated
with more than 400 million mu of cultivated land or about
one-fourth of the country’s total. The trunk and
branch rivers of the Yangtze River boast a total power
potential of 268 million kilowatts, or 40 percent of the
country’s total, and a navigable length of more
than 70,000 kilometers which makes the Yangtze River the
major water transport artery between west and east. The
river used to be a natural barrier between north and south
but is now spanned by giant bridges at Wuhan, Chongqing
and Nanjing. And in recent years, Chinese scientists have
explored the possibilities of channeling the plentiful
waters of the Yangtze River to the water-deficient north.
The
Yangtze River starts at he Jianggendiru Glacier on the
southwestern foothills of the 6,621-m, snow-covered Geladandong,
the main peak of the Tanggula Mountains I southwestern
Qinghai Province. It flows past Qinghai, Tibet, Yunnan,
Sichuan, Hubei, Hunan, Jiangxi, Anhui, Jiangsu and Shanghai,
where it empties into the East China Sea. Important cities
along the way are Chongqing, Wuhan, Nanjing and Shanghai.
With more than 700 tributaries, the Yangtze River system
has a total catchment area of 1.8 million square kilometers,
19 percent of the country’s total area, which mainly
lies in the sub-tropical zone. Its tremendous annual flow
to the sea averages 1,050,000 million cubic meters, or
morethan 20 times that of the Haunghe River.
The upper reaches of the Yangtze River start at its headstream,
the Tuotuo River, and goes to Yichang in Hubei Province.
The section down the Tuotuo is called the Tongtian River,
and the section from Yushu County in Qinghai to Yibin
City in Sichuan is called the Jinsha River. The section
downstream from Yibin is called the Yangtze River. The
flow from the upriver is 46.4 percent of its total. Te
section of the Jinsha River in the Hengduan Mountain Area
is lined on both banks by numerous mountain canyons. The
3,500-kilometer section from the headstream to Yibin has
a descent of more than 6,000 meters, or 90 percent of
the total drop of the Yangtze River. Most of the river’s
abundant power potential is concentrated in this section,
where large hydroelectric power stations can be built
in its numerous gorges and canyons. The famed Hutiao or
“Tiger Leaping” Canyon in Lijiang County,
Yunnan, one of the world’s largest, is 16 kilometers
long with a drop of 170 meters. The canyon itself is 2,500-3,000
meters deep and only 30 meters wide at its narrowest point.
At Yibin, the Yangtze River enters the Sichuan Basin,
where it is met by the Minjing, Tuojiang, Jialing and
Wujiang rivers. Here, the section of the river widens
as its voluminous waters rush eastward towards the famous
Three Gorges. The Three Gorges, also known as the Yangtze
River Gorges, are the Qutangxia, Wuxia and Xilingxia,
and cover the 204-kilometer section from Baidicheng in
Fengjie, Sichuan to Nanjinguan in Yichang, Hubei, with
a drop of 120 meters. Here, the river is hemmed in by
the steep rock faces of the peaks of the Wushan Mountains,
which, owing to continuous crustal uplifting movement,
rear 500-1,000 meters over the river surface. As the Yangtze
River cuts its way through the mountains, its bed becomes
narrow, less than 100 meters at its narrowest points,
forming the magnificent gorges that have drawn tourists
fro far and near. The swift and violent current on its
steep, narrow bed provides an abundant source of power.
The middle reaches of the Yangtze River Rive cover the
section from Yichang in Hubei to Hukou in Jiangxi. From
Yichang the river enters the plain, where it becomes much
wider and is joined by the Xiangjiang, Zishui, Yuanjiang
and Lishui rivers of the Dongting Lake system; the Ganjiang,
Fuhe, Xinjiang and Xiushui rivers of the Poyang Lake system;
and the Hanshui River, the longest tributary of the Yangtze
River. With its numerous tributaries and lakes and large
amounts of converging waters, the middle section of the
Yangtze River accounts for 47.3 percent of the river’s
total runoff. The section of the Yangtze River from Zhijiang
in Hubei to Chenglingji in Hunan is known as the Jinjiang,
where the numerous bends and shoals can retard flow, obstruct
navigation and cause frequent floods. Over the past decades,
much has been done to straighten out the convoluted section
has been shortened by 80 kilometers.
The lower Yangtze River starts from Hukou to its estuary.
Here, the increased flow is only 6.3 percent of the river’s
total and the Huangpu is the largest of the few tributaries.
The section from Yangzhou to the river mouth used to be
known as the Yangtze. In its lower reaches, the Yangtze
River is wide and deep: 18 kilometers wide near Nantong,
and 80-90 kilometers wide in its outlet to the sea. Nanjing
and Hukou along the lower section can be reached by ships
of 10,000-ton and 5,000-ton classes respectively. Few
large rivers in the world have channels as deep as that
of the Yangtze River.
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