关键词: 黑河流域, 生态需水量, 分类, 估算

Abstract: The water demand by the ecosystem in arid inland river basins has not been still given a clear and exact definition.It was related to the regional water resources estimate, water resources utilization plan and eco-environmental protection.Based on the principles and the classifications of eco-demand water in the arid inland river basins of northwest China, the estimate methods of eco-demand water volume were discussed.As a case of study, the eco-demand water in the Heihe River basin was calculated by threemethods: two of groundwater evaporation model and one of the vegetation evapotranspiration model.Taking 1995 as the datum year, the water demands of the shelter-forest ecosystem in artificial oasis in the middle reach and the desert natural oasis in the lower reach of Heihe river basin, were alculated respectively.The results show that: the eco-demand water of the shelter-forest ecosystem in artificial oasis in the middle reach was about 2.1×10⁸~2.16×10⁸ m³, and the eco-demand water of the desert natural oasisin the lower reach of Heihe river basin was about 5.23×10⁸~5.7×10⁸ m³.The lowest water demand for preserving the present oasis area was about 5.7×10⁸ m³ based on rational usage of water resources.If the life water demand of people and livestock and the water lose in the water transporting process were considered, the incoming runoff through the Langxinshan Section, demanded for preserving the present'oasis area before 2015, was about 6.O×10⁸ m³.If the oasis area be regained to the level at the primary of 1980s,the incoming runoff would be about 8.9 ×10⁸ m³, and the runoff through the Zhengyixia Section must be reached at 10.9×10⁸~13.1×10⁸ m³.

Key words: Heihe River basin, ecological demand water, classification, estimating methods