高寒山区流域水文模型构建及模拟不确定性分析研究

项目名称： 高寒山区流域水文模型构建及模拟不确定性分析研究

项目编号： No.51509067

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 水利工程

项目作者： 李彬权

作者单位： 河海大学

项目金额： 20万元

中文摘要： 高寒山区水文模型的构建有其独特性，主要表现为冻融条件改变了水分入渗规律和蒸散发水分来源组成等，产汇流过程也对土壤冻融产生反馈。目前对高寒山区水文模型的理论方法还缺乏完整的认识，模型发展还不成熟。研究表明，寒区流域融冻期的产流以蓄满产流为主、兼有融冻锋面以上分层产流的特点。本项课题以西藏纳木错流域为典型研究区，以新安江水文模型产汇流框架为基础，结合野外小型蒸渗仪观测实验、人工降雨产流实验、张力水入渗实验和室内土壤物理特性测定等分析典型下垫面土壤水力特性和蒸散发的参数规律，构建适用于高寒山区的松散式水文模型。借鉴积雪覆盖衰减曲线概念模拟季节性积雪的空间分布变化；结合基于气温指标的度日因子法与太阳辐射估算冰川和积雪的融化水量；根据地面实测资料、多源降水数据和遥感反演实际蒸散发数据驱动水文模型并检验其适用性。同时，采用马尔科夫链蒙特卡罗抽样技术分析降水不确定性和模型参数不确定性对模拟结果的影响。

中文关键词： 水文模型；产流模式；水文不确定性；纳木错流域；高寒山区

英文摘要： Watershed hydrological model for alpine cold regions has its unique characteristics in model structure, which highlight the changes in infiltration law and water source of evapotranspiration caused by melting processes of glacier, snowpack and frozen soil and their feedbacks. However, people still have no correct and entire cognition with its theory of hydrological model in alpine cold regions, which is immature and still in its early stage. Previous studies suggested that, the runoff scheme in cold region is a combination of saturated runoff (Dunne) runoff and layering runoff above freezing front. Thus, this study focuses on a representative watershed of the Nam Co Basin (Tibet). Based on the the model structure of Xinanjiang hydrological model, a new loose typed hydrological model for alpine cold regions would be established. In this study,the field micro-lysimeter experiment, rainfall simulation and tension infiltration experiment and the laboratory test of soil physical properties will conducted to analyze the law of parameters of soil hydraulic properties and exapotranspiration for typical underlying surfaces. The model employes the depletion of snow coverage to simulate the changes of snow-covered area, and estimates the meltwater of snow and glacier based on the combination of temperature-index degree-day factor and solar radiation. Multisource dataset including ground observed data, precipitation products and remote sensing based evapotranspiration data force the model running and test the applicability of this model in the study basin. In addition, precipitation uncertainty and parameter uncertainty in the model simulation would be analyzed using the Markov Chain Monte Carlo technique.

英文关键词： Hydrological model;Runoff mechanism;Hydrological uncertainty;Nam Co Basin;Alpine cold regions