Introduction to Deserts and Desertified Regions in China - Combating Desertification in Asia, Africa and the Middle East - page 9

Tabl e 1. 2 Areas of
desertified land in China
classified by different
processes

Types of desertification Area (km 2 ) % of total

Wind erosion 379;600 44:1

Wat er erosi on 394;000 45:7

Salinization 69;000 8:3

Engineering construction 19;000 1:9

Tot al 861;600 100:0

4 Desertification in China

Deserts (P:ETP ratio 0.5) and desertified land is mainly distributed in arid, semi-

arid and dry sub-humid areas, covering 13 provinces and autonomous regions in
North-west China (including part of Tibet) and in Northeast China (Fig. 1.2 ). Gobi
and sandy deserts cover an area of about 1,530,000 km 2 , which is equivalent to
15.9 % of the national area (Ci and Yang 2010 ;Luetal. 2005a , b ). According to
Zhu ( 1998 ) the existing desertified land area in China is 861,600 km 2 , accounting
for 8.97 % of the total land area, of which desertified land area induced by water
erosion covers 394,000 km 2 , making up 45.7 % of the total desertified area; wind-
erosion induced desertified area is 379,600 km 2 , or 44.1 %; and desertified area
caused by physical and chemical actions (such as secondary salinized land) occupies
88,000 km 2 , or 10.2 % (Table 1.2 ).
The Chinese Academy of Sciences has published a map of deserts and deser-
tification, which shows that the total area of China's sand, gobi and stony deserts
is 1.57 million km 2 . China's sand deserts cover an area of 684,000 km 2 , including
446,000 km 2 of shifting deserts. Most of the deserts are found in western China,
covering an area of 582,000 km 2 , and the east, which has deserts of 102,000 km 2 ,
according to the map. The largest deserts include Taklimakan, Badain Jaran,
Gurbantunggu, Tengger and Qaidam.
The inclusion of the hyper-arid areas (deserts) as set out in Table 1.2 distorts
the nature of the problem of desertification and its control and reversal in China.
Therefore, desertification in China should not include original desert such as sandy
desert, rocky or gravel desert (gobi), salt desert, wind-erosion related yardang relief
(Fig. 1.4 ) and frigid desert resulting from purely natural factors. With regard to
bedrock-exposed stony hills (bare rocky relief), only the naturally formed bare
rock landscape such as karstic fenglin (Peak forest) and fengcong (cluster forest)
is differentiated from areas where the top soil has washed-off and bedrock exposed
rocky slopeland resulting from human activities such as cultivation of steep slope
for cultivation. Only the latter can be referred to as rocky desertification. In terms
of water erosion related desertification, it merely means serious land degradation
marked by bad land or rocky (fragmental) slopeland occurring due to a serious
decline or even loss of land productivity resulting from serious fluvial erosion
caused by human activities rather than simply referring to all that related to soil
and water loss as desertification.
Since desertification is closely related to human activities, the time factor is
important (Dahlberg 1994 ). Desertification refers to land degradation caused mainly

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