摘要
由于参数较少且具有明确的物理学意义,基于水热平衡理论的Budyko假设常用于定量分析以及评价气候变化和植被变化对实际蒸散发的影响,对研究流域水量平衡和能量分配具有重要意义。依据位于我国北方密云水库上游的潮河流域1961—2015年的水文气象数据,选取了4种基于Budyko假设的模型来研究潮河流域水热耦合平衡关系,确定了该流域最适用模型以及模型参数最优值,并且采用情景设置法分析了流域实际蒸散发对气候以及植被变化的响应。结果表明:(1)与经典Budyko模型相比,采用流域下垫面参数修正的Budyko模型计算实际蒸散发的精度更高。其中,傅抱璞模型精度最高,决定系数、相对误差、纳什效率系数和均方根误差分别为0.85、4.30%、0.82和27.66 mm;(2)对傅抱璞模型下垫面参数ω进行优化,确定适用于潮河流域的模型参数取值为2.54,优化后的傅抱璞模型能够更好地反映流域实际蒸散发的变化特征;(3)情景模拟表明,气候变化和植被变化的共同作用导致潮河流域实际蒸散发的上升。其中,气候变化是引起流域蒸散发变化的主要驱动因素。
The Budyko hypothesis, less parameters and definite physical significance, was used to quantitatively analyze the effects of climate changes and vegetation dynamics on actual evapotranspiration. It is of great significance to study the water balance and energy distribution in Chaohe watershed. We used the Budyko empirical model to verify the water-energy balance theory based on the hydrological and meteorological data from 1961 to 2015 in Chaohe watershed. The most suitable model of the basin and the optimal values for the model parameters were determined. Furthermore, we quantitatively analyzed the impacts of vegetation dynamics and climate changes on the actual evapotranspiration. Results showed that the Budyko model modified by underlying surface parameters improved the accuracy of predicting actual evapotranspiration compared to the classical Budyko models. The Fu Baopu model had the highest precision in the Chaohe watershed; the mean relative error, the Nash efficiency coefficient, and the coefficient of determination were 27.66 mm, 0.82 and 0.85, respectively. Using the optimizing model parameter (2.54), the Fu Baopu model could better reflect the changed characteristics of the actual evapotranspiration. Finally, the scenario analysis indicated that vegetation dynamics and climate variation in Chaohe watershed played a positive role in actual evapotranspiration; climate changes are a major driver of the increase in actual evapotranspiration.
作者
曹文旭
张志强
查同刚
王盛萍
郭军庭
许行
CAO Wenxu;ZHANG Zhiqiang;ZHA Tonggang;WANG Shengping;GUO Junting;XU Hang(College of Soil and Water Conservation,Belting Forestry University,Beijing 100083,China;North China Electric Power University,Beijing 102206,China;Department of Biology,Western University,N6A 3K7,Canada)
出处
《生态学报》
CAS
CSCD
北大核心
2018年第16期5750-5758,共9页
Acta Ecologica Sinica
基金
国家自然科学基金项目(41140011)
国家林业公益性行业科研专项(201204102)
关键词
植被变化
气候变化
实际蒸散发
傅抱璞模型
潮河流域
vegetation dynamics
climate changes
actual evapotranspiration
Fu Baopu model
Chaohe watershed