新疆塔里木河断流趋势分析与减缓对策

Dried-up trend of Tarim River and the countermeasures for mitigation

塔里木河断流的趋势日益严峻,主要表现在断流长度不断增加,断流时间持续加长,如果这种趋势不能遏制,将大大增加向塔里木河下游生态输水的难度,对流域生态安全和下游"绿色走廊"的保护产生重大影响。通过对塔里木河断流趋势和水文情势的分析计算,探讨了引起塔里木河断流点上移、断流时间和断流河道加长的原因以及河道断流态势进一步发展可能给塔里木河流域生态安全带来的影响。进一步分析塔里木河流域水土资源管理和水情变化与河道断流的关系,提出塔里木河上游源流区灌溉面积增加是导致进入干流水量减少、河道断流的主要原因,流域大面积垦荒和用水量增加加剧了河道断流趋势的发展。建议实施流域水资源统一管理,强化塔里木河流域管理局管理职能,加强对土地资源的管理,加快对天山地区岩溶地下水的研究与开发,关注山区水库修建可能对塔里木河断流和生态带来的新问题。

In the past 50 years, because of agricultural reclamation on a large scale and high strength explotation of water resources in the headstream areas, the runoff quantity and volume of the headstreams flowing into the mainstream were decreased. Water systems of the basin were changed greatly. Many branches have lost the hydraulic relationship to the surface water. Now, there are only four headstreams flowing into the mainstream. If there were no headstreams, the mainstream would dry up because the Tarim River is a pure dissipation one. The condition of dried-up riverway got serious increasingly in the Tarim River Basin, for example, the length of dried-up riverway increased continually and the duration of dried-up days became longer. This situation strengthened the difficulties in ecological water conveyance to the lower reaches, and induced the great influences on ecological security of the Tarim River Basin and the lower ＂Green Corridor＂. Combined with the variation of mainstream runoff volume and the state of dried-up riverway, firstly the reasons why dried-up location traced to the source gradually and the duration of dried-up days was longer than before were discussed, and then, their potential influences on ecological security of the Tarim River Basin was analyzed. By further analysis on the relationship between water - land resources management of the Tarim River Basin, and the state of water and dried-up riverway, it was put forward that increasing acreage of plantation was the main reason that runoff volume flowing into the mainstream decreased and riverway dried up. Wasteland opening-up on a large scale and the large water utilization quickened the development of dried- up riverway. In the end, some suggestions were put forward, such as implementing uniform management of water resources in the basin, strengthening the management functions of the Tarim River Basin Management Administrator, intensifying land resources management, adjusting the structure of agriculture economy, harmonizing the conflicts between the economic development and the ecological protection, quickening the research and development on groundwater in Tianshan Mountain region, and paying attention to the new ecological problems produced by reservoir constructions in mountainous area. This paper aims at supplying a decision-making gist for water resources management and sustainable development of society, ecology and economy.