基于概率Budyko方程的流域未来可用水资源比例预估

Estimation of Future Water Availability Ratio in the Catchment Based on the Probability Budyko Equation

准确评估可用水资源量对水资源规划管理、维护生态完整性和社会经济发展至关重要。基于流域下垫面特征的概率Budyko方程和降尺度后的CMIP5气候模式数据,预估了4个典型流域未来水文气象变量及其可用水资源比率的分布和不确定性。结果表明:4个典型流域(黑河流域、滦河山区、汉江丹江口以上流域和赣江栋背以上流域)未来潜在蒸散发量均显著增加,而降水的增加趋势不明显;流域可用水资源比率值随着湿润程度的增加而增加,且可用水资源比率的不确定性从高到低依次是滦河山区、赣江栋背以上流域、汉江丹江口以上流域和黑河流域;不同的排放情景对4个典型流域可用水资源比率的分布及其不确定性影响较小;在加入相同的下垫面因素(植被覆盖指数)后,干旱区域(黑河流域)比湿润区域(赣江栋背以上流域)可用水资源比率的预估更加精确。

Estimating continental water availability accurately is of great importance for water resources planning and management,maintaining ecological integrity and socio-economic development. This paper projects the future hydro-meteorological variables and the uncertainty of water availability ratio in the four typical catchments based on the probability Budyko Equation and the downscaling CMIP5 model. The results show that the potential evapotranspiration in the four typical catchments( Heihe River Basin,Luanhe Mountain,Hanjiang River Basin above the Danjiangkou and Ganjiang River Basin above the Dongbei) has a significant increasing trend,while the increasing trend of precipitation is not obvious. The value of the water availability ratio increases with the increasing in the humidity. The uncertainty of the water availability ratio from high to low is the Luanhe Mountain,Ganjiang River Basin above the Dongbei,Hanjiang River Basin above the Danjiangkou and Heihe River Basin. The different emission scenarios have little effect on the distribution and uncertainty of the water availability ratio in the four typical catchments. After adding the same underlying surface factor( Normalized Difference Vegetation Index),the projection of the water availability ratio in arid area( Heihe River Basin) is more accurate than that in humid area( Ganjiang River Basin above the Dongbei).