Abstract:

The water diversion scheme is important for the sustainable development of the economic, social and ecological environment in different parts of the basin, especially for the rivers in arid areas. In order to curb the trend of ecological degradation in the lower reaches of the Heihe River, the Heihe River water diversion scheme, approved in 1997 by the Chinese government, was carried out in 2000. With the implementation of the water separation scheme, the allocation of domestic water, production and ecological water tends to be reasonable, and the trend of ecological environment deterioration has been relieved. However, there are still queries on the rationality of water diversion schemes because it is difficult to complete water diversion indicators in wet years. Therefore, it is necessary to comprehensively analyze the implementation of the water diversion scheme and evaluate its adaptability in the Heihe River under the changing background. In this paper, based on the analysis of the impact of water diversion scheme, the technical characteristics and adaptability of water diversion under the changing background were analyzed. By establishing water resource allocation model of the Heihe River, the implementation of water resource allocation under different water demands and the operation of Huangzangsi (Huangzang Temple) Reservoir for long-time series (from 1958 to 2012) were simulated, and then the adaptability of water diversion schemes was analyzed. The result shows that the Heihe River water diversion scheme cannot meet the requirements of water diversion under the current condition due to the changes of economic society and river connectivity in the Heihe River basin. Water diversion indicators can be accomplished when the area of farmland in the middle reaches decreases to the level of 2000 and the construction of Huangzangsi Reservoir is finished, but there is still over exploitation of groundwater in the middle reaches. In conclusion, "97" water diversion plan is inadaptable to the current situation to some extent on the basis of the economic, social and hydrologic conditions of the Heihe River in the mid-1980s.

Key words: Heihe River "97" water diversion scheme, impact analysis, long-time serial simulation, adaptability analysis, changing background