'98长江洪水位特点及其对策研究

Characteristics of 1998 Yangtze River Flood Level and Countermeasures

１９９８年长江干流洪水位一直居高不下的原因是：长江流域的强降雨时间长、范围广；洪峰来势猛、间隔短；长江上游水土保持差、吸纳雨水能力弱；行蓄洪区域大幅度减少；长江中下游退水缓慢．从四个不同角度探讨１９９８年武汉关水位未超过１９５４年，而其上下游最高洪水位却比１９５４年高得多的原因．提出降低长江干流洪水位的对策建议：增加上游土壤植被涵养雨水的能力；增加中下游湖泊及分蓄洪区蓄滞洪水的能力；增加河道的槽蓄能力和泄洪能力；增加水库调蓄洪水的能力．

The causes of high 1998 Yangtze River flood discharge level are:①long time heavy rainfall in the Yangtze River basin,②quick arrival of flood peaks and very short intervals,③poor performance of water and soil conservation works in rain areas,and④reduction of the flood retarding area.As a result,the flood level reduce remained high on the middle and lower reaches of the Yangtze River.From the four causes it is can be seen why the maximum 1998 flood level at Wuhan is lower than that of 1954,but on the upper and lower reaches the level is higher.Suggestions to lower the flood level on the Yangtze River are presented.It is necessary to increase rain holding capacities of the upper drainage areas;to improve flood retarding capacities of lakes and flood by pases,flood discharging capacity of river channels,and to enhance flood regulating process of the reserviors.