哈密——一个典型的地下水补给型荒漠绿洲区

由绿洲及其所在荒漠盆地平原与周边山地共同构建的哈密盆地地域系统，是我国干旱区典型的以地下水资源为主，而发育和不断扩大的荒漠绿洲区。盆地内独具一格的水循环系统，表现出水资源在流域水循环过程中形成和转化。由于荒漠盆地平原系统不产生径流，从山地进入荒漠盆地平原的水流就成为难一的水源。在哈密盆地河水出口后，即进入透水性强，粗粒松散的冲洪积扇，成为盆地平原地下水的形成区。潜水在冲—洪积扇缘溢出地面形成泉水，进而构成泉水河。冲—洪积扇积缘地带、地表平缓，土层深厚，发育成绿洲。盆地绿洲资源沿冲—洪积扇绿呈一字线，分80多个小的个体，散布于盆地的中央，将盆地黑戈壁与灰荒漠分为两半。

Hami: A Typical Oasis Group Nourished by Ground Water in Arid Land

Consisted of oases and their surrouding desert plain and mountains, Hami basin is a typical oasis group, which develop and is being enlarged relying on ground water in arid land of China. Inthe baisn, there is a unique water cycling system characterized by local formation and transformation of water resources. Generally, there is no any runoff formed in the desert plain, the streams from mountains are the only water source entering the basin. Water permeates into the ground while the streams ren to the upper parts of floodplains composed of coarse granular materials, which in turn become the formation area of ground water. On the lower edges of the floodplains with even land and deep earth, the ground water spilled over sruface becomes the springs nourshing the oases looked like a green belt along the lower edges of the floodplain separate two defferent landscapes of dark Gobi at the upper part and the gray desert at the lower part of the basin. These plentiful oasis resources being the persistent lifeblood play a vital role in the development of social economy and the flourish of civilization in Hami.