基于GLDAS-NOAH的长江流域蓝绿水资源时空变化特征

基于GLDAS-Noah水文模型,模拟长江流域蓝绿水资源量,并揭示其时空变化特征。结果表明:2000—2019年长江流域多年平均蓝水资源和绿水资源分别为420.24 mm和686.95 mm,绿水资源约是蓝水资源的1.62倍。近20 a来长江流域蓝水资源、绿水资源和绿水系数呈不显著增加趋势,2000—2019年蓝水资源与绿水资源变化速率分别为3.26 mm/a 和2.27 mm/a。从年内分配上看,蓝绿水资源在7—8月份较多,占全年的29%~32%;在1 —2月份较少,占全年的5%~6%。从空间分布来看,蓝水资源呈现东南高西北低的分布格局,绿水资源呈现东高西低的分布格局,而绿水系数呈现西北高东南低的分布格局。科学全面评价蓝绿水资源可以为优化水资源利用模式、提高水资源利用效率提供科学依据。

Spatial and Temporal Variation Characteristics of Blue and Green Water Resources in the Yangtze River Basin Based on GLDAS-NOAH

The blue and green water resources in the Yangtze River basin (YRB) were simulated by using the GLDAS (Global Land Data Assignment System) Noah hydrological model,and then the distribution of blue and green water resources and their temporal and spatial changes were revealed. Results demonstrate that from 2000 to 2019,the multi-year average blue water resource and green water resource in YRB was 420.24 mm and 686.95 mm,respectively,and the latter was about 1.62 times of the former. Over the past two decades,the blue water resource,green water resource and green water coefficient in the YRB showed insignificant increasing trends,and in particular,the change rate of blue water resource and green water resource was 3.26 mm/a and 2.27 mm/a during 2000-2019,respectively. On monthly scale,the blue and green water resources expanded in July and August,accounting for 29%-32% of the whole year,while shrank in January and February,accounting for 5%-6% of the whole year. On spatial scale,blue water resource distributed in a pattern of higher in the southeast and lower in the northwest,while green water resource higher in the east and lower in the west,and green water coefficient higher in the northwest and lower in the southeast. Scientific and comprehensive evaluation of blue and green water resources can provide scientific basis for optimizing water resources utilization mode and improving water resources utilization efficiency.