Agriculture Reference
In-Depth Information
CHAPTER TWENTY-EIGHT
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M onitoring Agricultural Drought in China
G UOLIANG TIAN AND VIJENDRA K. BOKEN
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Droughts account for more than half of the total number of natural disas-
ters faced by China. Serious droughts impact industrial production, water
supply, people's lives, and the ecological environment, which causes signifi-
cant losses to the national economy. Because of increasing water shortages,
drought has become one of the most important factors that limits agricul-
tural production, especially in the north where droughts occur frequently.
According to the Chinese terminology, if reduction in crop yields in an
area is more than three-tenths of the average, the area is called a “damaged
area,” and if the reduction is more than eight-tenths, the area is declared a
“nonyield area” (Lu and Yang, 1992; State Statistical Bureau, 1996; Chen,
2000).
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H istory of Droughts in China
Drought has been the most serious natural disaster in Chinese history.
Serious droughts occurred more than 1000 times from 206 B.C. to 1949
A.D. (Zhang, 1990; Li and Lin, 1993), or once about every two years. Over
the years, the eastern part of China has become more drought prone.
Drought impacts have lessened since 1949 because the government has
improved irrigation facilities. Nevertheless, agricultural production is still
affected by drought because yields of most crops depend on weather con-
ditions. Figure 28.1 shows the yearly variation in the total area affected by
droughts since 1949. The most serious droughts occurred during the 1960s
and the 1970s, and drought area has gradually increased (figure 28.1, table
28.1). Although serious drought occurred during 1978-79, droughts were
mild during 1970-77. The droughts always damaged a greater area than
did floods in a decade.
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