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| Desertification Processes and Developmental Tendency in Taklimakan Desert Region |
| Zhu Zhenda |
| Institute of Desert Research, Academia Sinica |
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Abstract The Tkalimakan Desert, situated in the inland basin where there are plenty of alluvial and lacustrine deposit, was gradually formed in Mid - Pleistocene and Holocene under the extreme dry and windy climate. It is a huge and moving sandy desert with complex landforms, However, there are also desertification problems for the deserts mainly formed by natural factors, The desertified land in the Taklimakan Desert Region covers an area of 28,266 km2,or 9.2% of the total area, of which 6.5% was formed in historical period and 34.9% in contemporary age. The desertification process of historical period in this region mainly occurred in the oases of lower reaches of rivers in the southern and eastern parts of the desert. Owing to the ancient rivers changed their courses (caused by natural or anthopogenic factors) and the reduction of phreatic surface, farmland and settlement were abandoned, thus forming the desertified land. In the northern part, both sides of the Trim River and frontal margin of diluvial and alluvial fans south of the Tianshan Mountain, dry sandy riverbed or abandoned farmlands turned into desertified land due to the river changed its course or long period of irrational irrigation caused the rise of water table and severe secondary salinization of soils. For nearly one hundred years, the desertification process in the Taklimakan Desert Region was aggravated thanks to the interferences of man-made factors and misuse of natural resource destroyed the fragile system, of course, local places resulted from sand dune encroachment. Based on the formation causes, the desertified lands can be divided into three types: l.Sand dune encroachment type 2.Sand dune activation type 3.Gobi sand drift type According to the developmental processes and present status of desertification in the Taklimakan Desert Region, the developmental tendency of desertification was predicted and its controlling measures were suggested. 1. "Green Corridor" area in lower reaches of the river at fringe of the Taklimakan Desert: In the past 25 years, desertification developed rapidly, belonging to severe desertification. It's necessary to work out an overall plan so as to rationally allot water resource in upper, middle and lower reaches: use land resource with establishing grassland as the main aspect; establishing wind breaks to protect farmland, settlement and roads. 2.Shrub sand mound area at fringe of newly reclaimed region: Shifting sand is rapidly explanding, measures must be taken to protect the existing vegetation, in addition to, it needs to establish artificial protective forest at fringe and within the reclaimed area by using trees and shrubs. 3. River banks situated deep in the desert: wind erosion is serious. It's not suitable for the farming here due to high water table and soil secondary salinization. However, there is vast area of natural populus diversifolia forest, therefore, it suits to establish natural preserve.
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Published: 20 September 1987
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1987, Vol. 7 
