丝绸之路沿线内陆河流域水循环闭合及其不确定性研究

The endorheic basins along the Silk Road is one of the important channels for the overall strategic deployment of China's "One Belt, One Road" initiative. However, the water environment crisis in this area is very serious. Up to now, the hydrological pattern of the endorheic basins along the Silk Road is known little, and few quantitative assessments of the water cycle balance and hydrological uncertainties in these basins have been conducted. This proposal aims to make up for the lack of ground-measured data in the region using the data captured through multi-source hydrological remote sensing data. In the framework of Bayesian method with integrated multi-source remote sensing data, the global parameter optimization combined with multi-objective function is employed to estimate the posterior distribution of parameters in the hydrological model across endorheic basins along the Silk Road. On this basis, the data provided by multi-source hydrological remote sensing products and hydrological model are combined to quantitatively analyze the water balance and hydrological process uncertainties in the endorheic basins along the Silk Road. The expected results will theoretically promote the study on the spatial-temporal patterns of water cycle and the responses to climate change in these regions. Furthermore, it will enrich the model parameter optimization solutions based on multi-source remote sensing data and provide valuable support to the scientific water management of the endorheic basins along the Silk Road.

作为我国“一带一路”总体战略部署的重要通道之一，丝绸之路沿线的内陆河流域水资源危机十分突出。但我们对该地区的生态水文格局知之甚少，缺乏对流域内水循环平衡与水文过程不确定性的量化评估。本项目将采用经过充分验证的多源水文遥感数据产品来弥补该地区地面实测数据的不足。在贝叶斯理论框架下融合多源遥感数据，并采用多目标函数的全局参数优化方法对分布式流域水文模型的最优参数进行合理估算，以拓展模型在丝路沿线内陆河流域的应用。在此基础上，综合利用多源水文遥感数据与模型模拟结果，定量化分析丝绸之路沿线内陆河流域的水循环闭合问题及其水文过程的不确定性。其预期成果将在理论上促进对该区域水循环时空格局、趋势变化以及与气候变化响应的研究。在实践上，将丰富和发展基于多源遥感数据的水文模型参数优化解决方案，并为丝路沿线内陆河流域科学水管理提供支持。

通过前期收集遥感与地面观测的水文气象资料，改进与优化全新的生态水文模型在丝路沿线主要流域的适用性与准确度，进而获得长时序且高分辨率的流域内主要水循环要素的时空连续分布特征。并在此基础上，根据土壤水量平衡原理，融合多源微波遥感土壤水分数据与卫星降水资料，估算了丝路沿线主要流域内灌区的农业灌溉用水量，解决了传统调查统计方法难以获得大尺度时空连续灌溉数据的问题，估算结果在几个数据相对充分的典型流域得到了验证。最后，针对丝路沿线主要流域进行多源数据融合，探索了近40年来这些流域主要水循环要素的时空演变规律，并结合农业灌溉用水数据，量化了人类灌溉活动对流域内可利用水储量造成的相对影响。本项目的研究成果将对丝路沿线内陆河流域的农业用水效率研究以及可持续水资源管理等方面提供重要数据支撑与理论依据。