流域环境变化下玛纳斯河融雪洪水的水文效应及其防洪风险不确定性问题研究

The Kensiwate Catchment was set as the research background in this project. Based on sufficient field investigation and data collection, started from the origin and evolution mechanism of snowmelt flood, the mechanism of snowmelt flood under environment change of Manas River was discussed and the main factors affecting the non-uniformity of snowmelt flood were analyzed. By using the method of frequency analysis of non-uniform snowmelt flood, design flood and design flood hydrograph under environment change were achieved and the impact of environment change on design flood was analyzed quantitatively. Using the method of statistical test, Bayes theory and risk analysis, the impact of different sample conditions on results of snowmelt flood calculation and flood control uncertainty by reservoir regulation were analyzed. The method that expressed the impact of different sample conditions on the uncertainty of the processes and results of snowmelt flood calculation was proposed, and the relative risk degree of the impact of environment change on flood control uncertainty by reservoir regulation was given. This study can provide scientific basis for the revision of technical data on flood control, regulation of water conservancy project and flood resources utilization.

项目以玛纳斯河肯斯瓦特控制流域为研究背景，在充分的现场调研和资料收集的基础上，从流域融雪洪水成因和融雪洪水的演进机理出发，探讨变化环境下玛纳斯河融雪洪水过程的作用机制，分析影响融雪洪水非一致性的主要因子，采用非一致性融雪洪水频率分析方法，推求变化环境下的设计洪水和设计洪水过程线，分析环境变化对设计洪水的定量影响。利用统计试验方法、Bayes理论及风险分析理论和方法，分析变化环境下不同样本条件对融雪洪水计算结果及对水库防洪风险的不确定性影响，提出变化环境下不同样本条件对融雪洪水计算过程及结果不确定性影响的表示方法，并给出环境变化对水库防洪不确定性影响的相对风险程度，为流域防洪技术资料修订、水利工程防洪调度及洪水资源利用提供科学依据。

建立“非一致性”水文序列下融雪洪水计算理论和方法，是确保水利工程防洪度汛安全、制定防洪调度方案的迫切需要。本项目在理论方面，揭示了变化环境下融雪洪水过程的作用机制、融雪洪水时间序列的非一致性、不同样本条件对融雪洪水计算过程及结果的不确定性影响，探明了影响融雪洪水成因的主要气候因子和下垫面因子、环境变化对设计洪水及水库防洪风险的不确定性影响，提出了基于水文模型的不同标准设计洪水计算方法、变化环境下不同标准设计洪水计算方法及不同样本条件对融雪洪水计算过程不确定性的分析方法，建立了基于风险理论的不确定性评估方法。在应用方面，为变化环境下玛纳斯河流域水利工程的设计、复核、防洪调度及干旱缺水地区合理利用洪水资源提供了理论基础和方法支撑。