干旱区受水资源胁迫的下游绿洲动态变化趋势分析——以黑河流域额济纳绿洲为例

Dynamic tendency of arid oasis under the influence of water resources decreaseA case study of Ejina oasis in Heihe River Basin.

干旱内陆流域下游绿洲的形成与演变对流域地表径流变化响应强烈 .采用绿洲生态斑块动态模拟、植被与水盐状态相关分析、生态需水量估算等方法 ,分别对黑河流域下游额济纳绿洲在不同分水方案与水资源利用情景下的变化趋势进行了研究 .结果表明 ,维持现状绿洲面积不再萎缩 ,在考虑水资源利用合理化的前提下 ,其最低净需水量为 5 .7× 10 8m3 ,如果考虑下游地区人畜生活用水及工业用水 ,同时考虑水量在输送过程中的散失损耗 ,为在近期 (2 0 15年以前 )维持现状绿洲面积 ,狼心山断面入境流量需达到6 .0× 10 8m3 ;而要使绿洲面积恢复到 2 0世纪 80年代初的水平 ,狼心山断面过水量应不低于 8.9× 10 8m3 ,正义峡断面下泄水量要求达到 10 .9× 10 8～ 13.1× 10 8m3 .

The runoff changes of arid inland river seriously influenced on the formations and changes of oasis in the lower reach. By the oasis patches dynamic modeling, the vegetation water interrelated analysis, and the estimation of water demand by the ecological system, the dynamic tendency of the Ejina oasis in the lower reach of Heihe River Basin under difference water resources allocating were studied. The results showed that the lowest water demanded for preserving the present oasis area was about 5.7×10 8m 3 based on rational usage of the water resources. Considering the water demand of people and livestock, and the water lose in the water transport process, the incoming runoff through the Langxinshan section should be about 6.0×10 8m 3 to preserve the present oasis area before 2015. To regain the oasis area to the level at the primary of 1980s, the demand incoming runoff should be about 8.9×10 8m 3, and the runoff through the Zhengyixia section should be 10.9×10 8～13.1×10 8m 3.