塔里木河干流中游灌区退耕封育效益分析

Benefit of Coverting Farmland to Grassplot in Upriver Irrigation Area of Tarim Valley

"塔里木河干流中游灌区9.00×103hm2退耕封育项目"是塔里木河流域近期综合治理工程的子项目,退耕封育的规模为9.00×103hm2,其中,库灌区退耕1.42×103hm2,河灌区退耕3.60×103hm2,泵灌区退耕4.00×103hm2。退耕封育后,农田灌溉用水改为生态灌溉用水,减少了用水量。人工种植的农作物被天然野生植被所替代,同时可提高对保留耕地的利用率,扩大耕地的播种面积,增加地表植被的覆盖度。退耕封育后,可节约水量9.70×107m3,除满足封育生态用水外,还可增加塔里木河下泄水量3.10×107m3。因此,退耕封育,从环境保护的角度来看,环境效益比较显著,不但可以改善项目区的生态环境,而且还可节约一定的水量用于塔里木河下游的生态环境建设,对维护塔里木河下游生态环境建设至关重要。

The project to convert farmland to grassplot for 9.00×10~3 hm^2 of the upriver irrigation area of the Tarim Valley is a segment of synthesis management of the Tarim Valley. The project involved 1.42×10~3 hm^2 reservoir irrigated area, 3.60×10~3 hm^2 river irrigated area and 4.00×10~2 hm^2 water pump irrigated area. After coverting farmland to grassplot, the gross irrigation water need is less and the water previously used for cropland irrigation becomes available for environmental application. While selfsown vegetation replaces some cropland, at the same time, the remaining farmland can be utilized for greater benefit. The gross saving of irrigatiion water can approach 3.10×10~7 m^3, which can flow to the lower reaches of the Tarim River. Converting farmland to grassplot can have marked benefits for surrounding areas, and is propitious to the improvement of the environment in Tarim Valley.