长江中游水旱灾害特点与水旱兼治对策——以“两湖”地区为例

The flood and drought calamity feature and controlling strategies of middle reaches of Yangtze River——a case of Hunan and Hubei district

历史资料和现代记录均清楚地表明,长江中游旱灾的发生频次和灾情与洪灾基本相当,中下游地区既是水灾的高发区,又是旱灾高发区.旱灾和洪灾多以2a为周期交替出现,常常是水旱同年.旱灾不但分布范围广,且延续时间长,其灾害损失不容忽视.20世纪中后期,长江中游水旱灾害呈明显的加剧趋势,其原因主要与生态环境变差,蓄洪空间减少和水利工程长期存在的重防洪、轻防旱等有关.建议:(1)转变传统的“防洪抗旱”观念为“防洪防旱”;(2)以20世纪60年代初期为参照,建立防洪防旱并举的河、渠、湖、塘网络系统;(3)扩大湖泊蓄水能力;(4)建立农田深沟深塘排蓄水系统.

The historical datum and nowadays＇ records have manifested clearly that the frequency and situation of drought corresponded basically to the catastrophic flood in the middle reaches of Yangtze River, where is the area that the flood took place frequently, also the area that the drought took place frequently. The drought and the catastrophic flood turned up by turns with the cycle of 2 a, and often turned up in the same year. The drought not only distributed widely but also lasted long, and it＇s loss can＇t be neglected. The drought and the catastrophic flood in the middle reaches of Yangtze River had the obvious increasing tendency. There are many reasons responsible for this but the main are： ecological environment being bad, the space of store floodwater being reduced and making much of preventing the flood but making little preventing the drought in the water conservancy for long-standing and so on. There are four suggestions： the one is to change the tradition concept of making much of preventing the flood but making little preventing the drought, to turn ＂preventing the flood and fighting a drought＂ into ＂preventing the flood and preventing the drought＂; the two is to establish the net system of rivers, sluice-ways, lakes and pools referring to the net system of the early 1960＇s; the three is to expand the ability of lakes saving water; the four is to establish draining and saving water system with the deep ditch and sluice-way of farmlands.