塔里木河的变迁与罗布泊的演化

干旱区河流及湖泊变化是环境演变的最重要标志之一。本文根据实际调查、历史记载和遥感图像解译,论证了塔里木河河道变迁及水量变化与罗布泊的演化关系。魏晋及其以前,塔里木河与孔雀河合流从北面入罗布泊,当时上游农业规模小,入湖水量多,罗布泊水域面积达到5350km2。此后,孔雀河入塔里木河,从南面经喀拉和顺入罗布泊,由于绿洲面积扩大,引水增加,到了清末罗布泊水域明显缩小,但还没有干涸。1921～1952年塔里木河再度与孔雀河汇流,又从北面入罗布泊,湖面扩大到1900km2,代表了这一时期的罗布泊水域,因此罗布泊不是20世纪30年代末40年代初干涸。1952年塔里木河与孔雀河分流,孔雀河单独入湖,水量减少,使湖面缩小,但直至1959年中国科学院新疆综合考察队对罗布泊进行考察时仍有广阔的水面,1961年仍未干涸。孔雀河灌区为扩大灌溉面积,于1958年和1962年,分别在普惠和阿克苏甫修了拦河大坝和水库引起下游断流。因此,罗布泊应在1962年以后逐渐干涸,直到1972年美国第一颗地球资源卫星照片上才得到反映。同时,还根据塔里木盆地绿洲发展、水资源利用及水系关系,分析了罗布泊干涸的原因及与塔里木河开发有着必然联系,主要是人类活动改变了地表径流的地域分配,上中游引水过多,造成下游断流和尾闾湖干涸。

CHANGES OF TARIM RIVER AND EVOLUTION OF LOP NUR

The change of rivers and lakes is one of the most important characteristics of environmental change in the arid area. Based on onsite survey,recorded history,and remote sensing image interpretation,this paper demonstrated the changes of Tarim River channel and stream discharge,and their relationship to the evolution of the Lop Nur. During Wei and Jin dynasty or before,the Konque River joined the Tarim River and flowed into the Lop Nur from the north. At that time,the agricultural scale of the upper reaches of the Tarim River was limited,the calculated flow into the lake was large,and the watering area of the Lop Nur could be up to 5350km2.Later,the Kongque River and the Tarim River joined at the Kara Heshun,and then flowed into the Lop Nur from south. Due to oasis expansion and the increment of drawing water,the watering area covered by the Lop Nur decreased. But the Lop Nur had not yet dried up in the late Qing dynasty. From 1921 to 1952,the Kongque River and the Tarim River joined into the Lop Nur once again from the south,and the area of the lake extended to 1900km2.In 1952,separating from the Tarim River again,the Kongque River flowed into the Lop Nur alone. Then the stream discharge decreased and the Lop Nur was narrowed,but had not dried up until 1961.In order to enlarge the irrigation area of the Kongque River,a dam was constructed in Huipu in 1958 and a reservoir was built in Akesupu in 1962,causing the set off of the lower reaches of the Tarim River,as well as the drying up of the Lop Nur after 1962. 