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中国沙漠 ›› 1985, Vol. 5 ›› Issue (1): 1-15.

• 论文 •    下一篇

塔里木河下游沙漠化特征及其发展趋势

凌裕泉, 高鹏恂, 金炯, 赵业凡, 何世水, 龚家东   

  1. 中国科学院兰州沙漠研究所
  • 收稿日期:1985-03-11 出版日期:1985-03-20 发布日期:1985-03-20

Characteristics of Desertification and Its Developmental Trend in the Lower Reaches of Tarim

Ling Yuqan, Gao Pengxun, Jin Jiong, Zhao Yefan, He Shishui, Gong Jiadong   

  1. Institute of Desert Research, Academia Sinica, Lanzhou
  • Received:1985-03-11 Online:1985-03-20 Published:1985-03-20

摘要: 近年来,由于塔里木河中上游截流,造成下游长期断水,生态环境的劣变导致沙漠化的迅速发展,并日趋严重。因而引起有关方面的极大关注,保护和恢复绿色走廊已被提到议事日程。一些研究者[1-8],从不同的角度,对绿色走廊的现状与未来进行了广泛有益的讨论。本文根据有关的资料,着重从风沙活动规律与活动强度方面,讨论塔里木河下游绿色走廊沙漠化的现状及其发展变化特征。结果表明;细沙和粉细沙是该地地表物质的主要组成部分(约占95%以上),在极端干旱的气候条件下,特别是在河流长期断流以及人为地强烈破坏天然植被之后,风沙活动的频率和强度均有较大程度的增加,已经成为严重的沙漠化地区,应该尽快地采取有效的防护措施。从沙丘移动速度的计算值(1米高的单个新月形沙丘移速为7.74米/年)来看,在近期甚至在一个相当长的时期内,还不致由于库鲁克库姆沙漠的移动而导致绿色走廊的覆灭,重演古楼兰的历史。目前由于沙漠化而造成直接危害地段(如阿拉干等)只是绿色走廊的几个缺口,而大部分地段上的天然植被仍能有效地起到防风固沙作用。因此,保护现有的天然植被是控制沙漠化发展的关键,合理解决塔里木河全流域用水,调整农、林、牧业生产比例,是恢复绿色走廊生态平衡的有效途径。

Abstract: During last recent years, degradation of ecological environment brought a rapid development of desertification and it is becoming grave with each passing day as a result of the dam and the catchment in the upper and middle reaches of Tarim River and due to the shortage of water supplies in the lower reaches. Therefore, greater concern is shown on the problem from all level authorities and the protection and the renewal of the "green belt" are brought to the agenda of environmental protection. Some research workers carried out wide-ranging discussions and studies on the status and the future of the green belt from different viewpoints. On the basis of relevant data, the status of desertification and its developmental trend and dynamic characteristics of the green belt in the lower reaches of Tarim River arc discussed in the study with respect to the aspects of the movemental law of wind and sandflows and their movemental intensity.The research result shows that fine sands and dust sands are the main composition of surface materials, namely,they occupy more than 95% of surface composition. Under extreme arid climatic condition, the frequences and intensity of sand and wind flows were obviously increased, especially when the dam and the catchment were constructed in the upper and middle reaches of the river and the destruction of natural vegetation was resulted from irrational human acti-vities. The severe desertified land areas are referred to be protected with acceptable measures. The calculating value (annual moving speed of individual barchan dune of 1 m high is7.74m) of the spread speed of sand dunes shows that the green belt won't be occupied by encroachment of shifting sands of Kuruk Kum Desert or the fact of the abandonment of the ancient Lulan won't be occurred in recent or in a certain period of time. At present, some sections of the green belt are directly influenced by the oc currance of desertification (for instance, Argan District), and most part of the area is still vegetated by natural green coverage and plays good role on wind prevention and sand stablization. Thereby, the protection of existing natural vegetation is a key measure to control the development of deseertification; the rational distribution of water supplies in the whole river valley of Tarim River and the acceptable orientation of land uses for farming, forestry and animal stocking are the effective ways to renew ecobalance in the area of the green belt.