李白站在黄河之滨,瑟瑟弹唱“黄河之水天上来,奔流到海不复回……”。今天,黄河上下,滔滔之势已渐渐隐去。且看下列一组数据:黄河断流自1972年开始,70年代最长年断流历时21天,80年代最长年断流历时36天,至90年代最长年断流历时急剧升高,从1991～1997年的7年中分别为16、82、61、75、122、133、226天; Standing on the bank of the Yellow River, Li Bai sang and “the water of the Yellow River came from the sky and went to the sea no longer ...”. Today, the Yellow River, surging trend has gradually disappeared. Let’s take a look at the following set of data: The Yellow River cutoff since 1972, the longest cut-off in the 1970s lasted 21 days, the longest cut-off in the 1980s took 36 days, and the longest cutoff in the 1990s rose drastically, From the years of 1991 to 1997, they were 16,82,61,75,122,133,226 respectively in seven years;