Study On The Restoration And Reconstruction Of The Lower Reaches Of Degraded Tarim River Ecological System

Tarim River, located in the arid region of the west of China, is the longest inland river in China, which is famous for its abundant natural resources and fragile eco-environment. However, Owning to irrational exploitation of water, land resources, the eco-environmental problems have been degraded increasingly. The main points are: groundwater level has descended to an obvious extent; nature vegetation has been degenerated completely; groundwater salination degree has increased along the Tarim River and relevant regions; desertification has developed quickly, wind-sandy disaster has been seriously increasing. Thus, study on the eco-environmental fragility and the degenerating status of natural vegetation in the lower Reach of the Tarim River is very important to harness and restore the degraded Tarim river ecological system.Based on the ecological theory, the long-term monitoring data and experimental results are adopted to analyze the basic reasons for eco-environment degeneration in the study area. It is considered that the eco-environment degradation both affected by the natural parameters and artificial activities. And then some methods for restoring the degraded ecological system in the typical areas of the lower reaches of Tarim River are discussed, which include ecological forestry construction, ecological water conveyances and partly restoring the farmland into forestry and grassland.The benefits from returing farmland into grassland and forestry were evaluated. The ecological benefits and economic benefits are obvious and are further proved by the increase of variety of soil water content and the vegetation diversity. Besides this, the synthesized benefit in the process of returning farmland into forestty and grassland, such as soil water saving, biodiversity protection, the physical quality of soil, amelioration of local microclimate, prevention of soil deserting and region economic development are all positive. Populus euphratica Oliv crown and the vegetation diversity tend to be increasing and the desertification has been controlled partly. Those changes indicate that the benefits of water conveyance in the lower reaches of Tarim River are promising.