Geoscience Reference
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4000
3000
2000
1000
0
-1000
-2000
1970s
1980s
1990-1994
1995-1999
2000-2004
Fig. 20.7 Annual rate of spread of sandification in China. In recent years the areas treated by
the methods outlined in Chaps. 2 and 3 of this topic have exceeded the areas succumbing to
sandification
plant population occurs infrequently. Recruitment (germination and successful
establishment) follows the rare co-occurrence of favorable climatic events. This is
why it is common to find even-aged stands of trees and shrubs in arid zone systems.
If a perturbation, such as land clearing is followed by heavy and sustained grazing,
then no recruitment will take place and as the old plants die there is no replacement.
In many of China's counties in Ningxia, Inner Mongolia and Gansu the local
officials report that the rate of expansion of desertified lands is proceeding at double
the rate of control measures. Clearly, this is unsatisfactory and better ways must be
found to reverse the trend. National efforts to combat desertification employ a range
of measures, some physical and others relate to socio-economic and policy change
(Lu et al. 2005 ).
Sandy desertification 1 (sandification) is of great concern (Wang Tao 2000 ). Until
recently the area of sandification was growing at a rapid rate, despite efforts to
combat it (Fig. 20.5 ). It is estimated that the rate of rangeland degradation in
semi arid and dry sub-humid areas is 90-97 %, and the annual rate of rangeland
degradation is accelerating but from 2004 onwards the rate of expansion of land
affected by sandification has declined and in some areas it has been reversed (Luo
and Zhang 2006 )(Fig. 20.7 ).
1 Sandification refers to sandy desertification. It is experienced in many areas of China from the
sub-humid Hulunbir grasslands in NE China to the edges of the various deserts in western and
northern China.
 
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