基于分布式大流域径流模型的中国西北黑河流域水文模拟(英文)

Hydrologic Modeling of the Heihe Watershed by DLBRM in Northwest China

水资源短缺是中国西北干旱地区长期的问题,区域人口增加、城市化扩张,加之气候变化的影响进一步加剧了西北地区水资源短缺,也使生活用水、灌溉用水、工业用水和维持生态系统稳定的用水危险加剧.采用分布式大流域径流模型(DLBRM)模拟黑河流域水文(中国第二大内陆河,流域面积128 000 km2)来理解区域的冰川和积雪融化水、地下水、地表水、蒸散发等方面的分布,评估气候变化对水文的影响和冰川退缩对中游和下游来水量的影响.模拟结果表明,黑河流域的大部分产流那源于黑河上游地区的祁连山.模拟1990—2000年黑河河流日流量变化结果认为,黑河中游正义峡给下游的供水为10×108m3,其中地表径流占51%,层间流占49%.中游地区沙土具有较高的蒸腾发能力,近一半的地表水被蒸发掉.模拟实践证明,分布式大流域径流模型可以结合气候变化、水资源管理方面的成果,改进流域水文模拟的精度.

Water shortage is a chronic problem in arid Northwest China. The increasing population growth and expanding urbanization as well as potential climate change impacts are likely to worsen the situation, threatening domestic, irrigation, and industrial supplies and even the survival of the ecosystems in Northwest China. This paper describes the preliminary work of adapting the Distributed Large Basin Runoff Model （DLBRM） to the Heihe watershed （the second largest inland river in arid Northwestern China, with a drainage area of 128 000 km^2） for understanding distribution of glacial/snow melt, groundwater, surface runoff, and evapotranspiration, and for assessing hydrological impacts of climate change and glacial recession on water supply in the middle and lower reaches of the watershed. Preliminary simulation results show that Qilian Mountain in the upper reach area produces most runoff in the Heihe watershed. The simulated daily river flows of the 1990---2000 indicate that the Heihe River discharges about 1 billion m^3 of water from the middle reach （at Zhengyixia station） to lower reach, with surface runoff and interflow contributing 51 and 49 percent respectively. The sandy lower soil zone in the middle reach has the highest evapotranspiration rate and also contributes nearly half of the river flow. Work underway focuses on the DLBRM model improvement and incorporation of the climate change and management scenarios to the hydrological simulations in the watershed.