分布式双源蒸散发模型及其在南广河流域运用研究

Study on application of distributed dual-source evapotranspiration model in Nanguang River basin

鉴于传统蒸散发模型基于单点计算,不能考虑流域下垫面条件对蒸散发影响的局限性,利用卫星遥感数据源,以四川境内的南广河流域作为研究对象,构建基于栅格单元的分布式双源蒸散发模型,实现研究区域蒸散发时空全过程计算。研究表明:基于遥感数据源的区域蒸散发计算值与蒸发站点实测蒸发值具有较好的一致性和相关性,相关系数为0.744,在相似的气象和下垫面条件下,蒸散发能力排序为:林地>灌木丛>水田>旱地>草地,模型研究成果对于流域蒸散发空间计算,以及定量分析土地利用变化对流域蒸散发影响提供一定的参考价值。

In view of the evapotranspiration model which is based on traditional single-point calculations and can't consider the effect of watershed surface conditions on evapotranspiration ,the paper used satellite remote sensing data and took Nanguang River basin in Sichuan basin as the research object so as to build distributed dual-source evapotranspiration model based on a grid unit .The model realized the calculation of whole process of evapotranspiration time and space in research area .The results show that the calculat-ed value and measured value of evapotranspiration based on the site area of remote sensing data source have better consistency and relevance ,the correlation coefficient is 0 .744 .Under similar weather and sur-face conditions , the sequence of evapotranspiration capacity:forest land >shrubbery>paddy field>dry land >grassland .The result can provide certain reference value for the space calculation of evapotranspi -ration in the watershed as well as quantitative analysis of effect of land use change on watershed evapo -transpiration .