变化环境下中国干旱综合应对措施探讨

我国干旱具有普遍性、连续性、季节性、地域性等特征,旱灾不仅直接影响我国的粮食安全,还进一步影响水循环及其伴生水环境、水生态和水沙过程。变化环境下,我国干旱问题显得尤为突出,表现在发生频率不断增加、受旱范围不断扩大、影响领域扩展、灾害损失加重,如何应对变化环境下的干旱,已成为我国实现和谐发展过程中亟待解决的关键问题之一。为有效综合应对我国的干旱问题,本文从三个时间层面上探讨了干旱的应对措施;从长期宏观发展战略层次上,构建与水资源承载能力相适应的经济社会发展模式(重点调整种植结构和工业产业结构),可从根本上减少干旱危害;在中尺度时段上,优化水资源调配体系是干旱综合应对的重点;在短尺度时段上,需制定有效应急预案,保障应急水源。

Integrated Strategies for Dealing with Droughts in Changing Environment in China

The aim of this study is to discuss the integrated strategies for dealing with droughts in changing environment in China by accounting for the characteristics and trends of droughts. Droughts show characteristics of universality, continuity, seasonality and regionality. It can significantly affect food security, hydrological cycle, water environment, water ecology, sediment and so forth. Drought issues become more and more serious under the condition of environmental changes, with showing an increasing frequency. The cope and areas of drought disasters have been expending. Disaster losses of droughts have also been aggravating. To this end, documenting the integrated strategies for dealing with droughts is critical. For the long term, the modes of economic and social development should not exceed water resources carrying capacity. It was suggested that water resources carrying capacity can be increased under the condition of industrial structure adjustment. The authors took Tangshan industrial structure adjustment for example. It was found that industrial water use in Tangshan decreased by 17.4%, saving industrial water of 140×106m3. Water resources carrying capacity could also be increased through planting pattern adjustment, which was demonstrated by the case of Tacheng planting pattern adjustment. Agricultural irrigation supply is the major portion of water consumption in Tacheng, with showing an increasing trend. Water resources regulation and allocation should be optimized at the middle stage, which is the critical point of the integrated strategies for dealing with droughts illustrated by the case of the Yellow River. The grain yield of the Yellow River basin was found to increase by 37.20×109kg, GDP increase by RMB 270.5×109 yuan and surface water consumption decrease by 2.0×109m3 since the Yellow River basin took the integrated water regulation. It was suggested that emergency water sources should be reserved in the short-term in order to meet a requirement for emergency plan when droughts occur. Emergency water should first meet domestic water demands and then production water demands. The sources of emergency water should be first from surface water and then groundwater, saving water first and then transferring water.