Agriculture Reference
In-Depth Information
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Figure 28.1 Area affected by natural disasters and droughts in mainland China since 1949.
Sp atial Distribution of Droughts
Figure 28.2 presents the spatial distribution of droughts from 1951 to
1991. In particular, four regions were identified where the frequency of
drought was significantly high (Li and Lin, 1993): (1) Huanghuaihai re-
gion in the North China Plain, (2) Hebei, Shanxi, Shandong, Henan, and
Shaanxi provinces, (3) the coastal south China, in particular the coastal
area in Guangdong and Fujian provinces, and (4) the southwestern part of
southwest China, mainly the southern part of Yunnan and Sichuan pro-
vinces. In addition, there is a narrow area in the western part of northeast
China and arid regions in Gansu and Xinjiang in northwest China that are
prone to drought (Li and Lin, 1993).
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Se asonal Characteristics of Droughts
A drought in China can be classified as a spring, summer, autumn, or
winter drought on a temporal or seasonal scale. The Qin Ling Mountains
and Huaihe River serve as an approximate dividing line on a spatial scale.
North of the dividing line mainly spring and summer droughts occur, while
south of the dividing line mainly summer, autumn, and winter droughts
occur. In some years, droughts persist for two or more consecutive seasons
and become highly destructive. The spring-summer and spring-summer-
autumn droughts are most frequent in Huanghuaihai region (North China
Plain), and spring-summer droughts are most frequent in northeast regions
of China. Winter-spring droughts mainly occur in southwest and south
China, while the year long and summer-autumn droughts occur in north-
 
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