基于遥感-模型模拟的玛纳斯河源区径流过程对冰雪变化的响应机制研究

The response of the river runoff to changes in glaciers and snow cover is a core subject in the field of water science, and a basic scientific question for making water adaption strategy to cope with climate change in arid regions. Toward this end, the study in the Manas River basin will (1) develop a hydrological model, which is established by modifying the glacier module in the HBV-D hydrological model and thereby can better reproduce the river runoff in the glaciated basin; (2) propose a calibration strategy, where the calibration of parameters is conducted based on remote sensing productions and partitioning hydrographic curves; (3) investigate the temporal and spatial changes in snowmelt and glacier mass balance, quantify the contributions of different discharge sources to the river runoff and understand the response of the river runoff to changes in glaciers and snow cover during the historical period. The results of the proposed study will offer valuable insights into the attribution of changes in river runoff, in support of sustainable utilization of water resources in the study area.

气候变化下径流过程对冰川积雪变化的响应机制是当今水科学研究的热点和难点，也是建立内陆干旱区水安全保障机制的基础科学问题。本课题以位于我国天山北坡的玛纳斯河源区为研究对象，(1)在HBV-D分布式水文模型的框架基础上，考虑云量对冰川消融的影响及冰川的动态演变，改进冰川消融模拟方法，从而提高该水文模型在冰川流域的模拟能力；(2)建立高寒山区日径流多源成分的识别方法，发展基于遥感信息及径流过程分割的模型参数化方法，以降低寒区水文过程模拟结果的不确定性；(3)模拟分析历史时期积融雪及冰川物质平衡的演变特征，阐明融雪径流、融冰径流开始时间及峰值的变化规律，量化不同时间尺度下融雪径流和融冰径流对总径流变化的贡献率，揭示流域径流过程对冰雪变化的响应机制。研究成果对提高河川径流过程变化机理的认识，实现流域水资源可持续利用具有重要意义。

气候变化引起的流域冰川积雪的迅速变化，正改变着新疆玛纳斯河流域水循环过程和水资源时空分布，这将对研究区粮棉生产及绿洲发展模式带来深远的影响。因此深入研究玛纳斯河源区冰雪变化及对流域径流过程的影响机制具有重要现实意义。本研究通过修订HBV-D水文模型中的空间离散方案和冰川消融计算方法，显著提高了该模型对冰川流域水文过程的模拟能力。比较了多目标法和多步率定法两种参数率定法对水文过程模拟结果的影响。最后，基于模拟结果分析了历史时期冰雪融水及冰川物质平衡的演变特征，消融期不同径流成分的贡献率及变化趋势。研究发现冰川区积雪消融发生提前的速率快于非冰川区；研究期内冰川物质平衡呈负平衡状态，由降水增加10%引起的物质平衡的增加未能抵消由气温升高1℃引起的物质平衡减少量；冰川径流对消融期总径流贡献率的年际变化范围为35%-64%，冰川径流及贡献率均呈现增加趋势。迄今为止，已发表含基金号标注的SCI论文4篇，参加国际学术会议2次，获得水利部大禹水利科技进步奖二等奖1项。研究成果已达到预期目标。