Perception of Drought and Water Shortage

Drought is generally viewed as a sustained and regionally extensive occurrence of below-average natural water availability, in the form of precipitation, runoff, or groundwater. Drought should not be confused with aridity, which applies to those persistently dry regions where, even in normal circumstances, water is in short supply. Normally the consequences of droughts are felt most keenly in areas that are in any case arid (UNESCO-WMO, 1985). Furthermore, the adverse effects of drought are noticeable only in those areas that are inhabited, and the trend of drought impacts intensifies as human activities increase. If arid regions with sparse population are hit by drought, little or no impact will occur to humans or economies. But if the region is densely populated and highly developed, countermeasures have to be taken to cope with drought disasters. It is important to note that although drought may have many adverse effects on human activity, it is also true that many human activities aggravate drought (Zhang Hai Lun, 1997). Below are examples of drought in different regions of China with different natural and socioeconomic conditions.

In southern China, which has a humid climate, population pressure has led to an increase in the number of rice crops (from one to two) in many areas, which has resulted in frequent drought in some places. For example, in Anhui Province (located in the Yantze River and Huihe River basins), various measures have been taken, including changing from dry farming to growing rice, changing from one crop of rice to two, and applying more water to wheat. These activities led to a total water use in the agricultural sector of 14 billion m3 in 1990, which is an increase of about 10 billion m3 compared to the early 1950s.

The north China plain, located in a subhumid region with annual precipitation ranging from 600 to 800 mm, is historically a densely populated region with highly developed agriculture. Drought impacts have been increasingly critical since the 1970s, with small and medium rivers dry year round. Even the Yellow River becomes dry intermittently. The overdraft of groundwater has resulted in environmental degradation, and the frequency of drought events continues to increase.

In the Xinjiang and Ningxia Autonomous Regions, situated in the northwest arid zone, the dry climate does not lead to drought disasters because of stable water supplies from the snowfed rivers (Xinjiang) and the Yellow River (Ningxia).

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