Geoscience Reference
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the last 2000 years. Today, the suspended load reaches
40 per cent by weight, making the Hwang Ho one of
the muddiest rivers in the world. Where the river
breaks onto the flatter coastal plain, vertical aggrada-
tion has built up a large alluvial fan-like delta from
Beijing in the north, to Shanghai in the south. The
river thus flows on the crest of a cone-shaped delta and
builds up its bed very rapidly during flood events. As
early as 2356 BC, the river channel was dredged to
prevent silting. In 602 BC, the first series of levees was
built to contain its channel. Despite these efforts, in
the last 2500 years the Hwang Ho has broken its banks
ten times, often switching its exit to the Yellow Sea
over a distance of 1100 km on each side of the
Shandong Peninsula (Figure 6.14). Associated with
these breakouts has been massive flooding - with the
result that China historically has suffered the greatest
loss of life in the world from flood hazards.
Between 2300 BC and 602 BC the Hwang Ho
flowed through the extreme northern part of its delta
in the vicinity of Beijing. In 602 BC, the river moved
slightly south to the region of Tianjin, and stayed
there until 361 BC, whereupon it underwent a
catastrophic shift south of the Shandong Peninsula.
For the next 150 years, the Chinese expended con-
siderable effort shifting it north again. In 132 BC, the
Hwang Ho switched to a course near the present
entrance, where dike building tended to keep it
stabilized, with minor channel switching, on the northern
side of the Shandong Peninsula until 1289 AD. For
this period, the northern part of the alluvial plain
aggraded - a process that steepened the topographic
gradient southward. With the fall of the Sung dynasty,
dike maintenance lapsed, and in 1289 AD the Hwang
Ho again switched south of the peninsula, where
it was allowed to remain for the next 660 years.
Land above 200 m
Beijing
Tianjin
2300-602 BC
132 BC-11
70-1048
1853
1048-1194
602-361 BC
Gulf of Chihli
11-70
Shandong Peninsula
Hwang Ho R.
1194-1289
N
1289-1494
Kaifeng
1494-1853
East China Sea
361-132 BC
1887-1889
Shanghai
Yangtze R.
0
100
200
300 km
Location of the Hwang Ho River channel: 2300 BC to the present (after Czaya, 1983). Dates shown are AD unless otherwise indicated.
Fig. 6.14
 
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