气候变化对洮河流域中上游水文过程的影响研究

Water resources are the key elements affecting economic and social development and ecological safety of the arid region of Northwest China. Climate change leads to temporal-spatial distribution of water resources, and then affects the watershed hydrological processes to a certain extent. Because of temperature rising, precipitation reduction, evaporation increasing , the landscape have degraded, the runoff have decreased and even blanked in the Taohe River, which pose serious challenges to the regional water resources utilization, ecological, economic and social sustainable development. River runoff change in upper and middle reaches of the Taohe River basin has a huge effect on socioeconomic development of the Longzhong and Longxi Loess Plateau areas where water resources are scarce and supplied by the Tao River diversion project. In this study, we focus on the Taohe River basin in the arid region of northwest China, based on hydrological and meteorological data, observed mountains precipitation gradient data, reanalysis grid data, and remote sensing image data, by using a variety of methods of mathematical statistics, and combining with the regional climate model and distributed hydrological model, to understand the temporal and spatial changes of climate in the Taohe River basin, then reveal the runoff processes in upper and middle reaches of the Taohe River and their response to climate change, and further estimate the runoff change trend of upper and middle reaches under different future scenarios. These will provide a scientific basis for water resources management and countermeasures in the Taohe River basin.

水资源是制约西北干旱区社会经济发展、影响生态安全的关键要素。气候变化导致水资源在时间和空间上的重新分配，从而在一定程度上影响流域的水文过程。由于气温升高，降水减少，蒸散发增强等气候要素的变化，地处西北干旱区的洮河流域出现地表景观退化和河川径流锐减等现象，对区域水资源利用、生态、经济和社会可持续发展形成严峻挑战。洮河中上游径流量的变化对通过“引洮工程”供水的陇中和陇西黄土高原水资源稀缺地区的社会经济发展影响巨大。本项目聚焦于西北干旱区洮河流域，利用气象和水文站等站点观测资料及本项目拟观测的山区梯度降水等数据，再分析格点数据及遥感影像等多源数据，综合运用多种数理统计方法，结合区域气候模式和分布式水文模型模拟，揭示洮河流域有器测记录以来气候变化的时空演变特征，辨析洮河中上游径流量对气候变化的响应规律，预估未来不同气候变化情景下洮河流域中上游径流量的变化趋势，为制定流域水资源管理对策提供科学依据。

水资源是制约西北干旱区社会经济发展、影响生态安全的关键要素。气候变化导致水资源在时间和空间上的重新分配，从而在一定程度上影响流域的水文过程。本项目聚焦于西北干旱区洮河流域，利用气象和水文站等站点观测资料及本项目拟观测的山区梯度降水等数据，再分析格点数据及遥感影像等多源数据，综合运用多种数理统计方法，结合区域气候模式和分布式水文模型模拟，揭示洮河流域有器测记录以来气候变化的时空演变特征，辨析洮河中上游径流量对气候变化的响应规律，预估未来不同气候变化情景下洮河流域中上游径流量的变化趋势，为制定流域水资源管理对策提供科学依据。在项目支持下，全面总结了国内外干旱半干旱区水文过程对气候变化和人类活动响应的现状及进展，系统回顾了国内外气候变化和人类活动对流域水文过程影响的发展历程和未来气候变化情景下对流域径流量的预估。在项目开展的具体过程中，深入分析了近几十年来洮河中上游蒸散发的时空变化特征及其影响因素，系统分析了洮河流域近几十年来径流量的变化特征和未来趋势，探讨了气候变化对洮河流域水文过程的影响。研究结果可以为干旱区水资源合理配置、水资源综合利用及可持续发展提供科学依据，特别是为洮河流域的调水配置及水资源综合利用提供重要的决策依据。