TOPMODEL模型拓展及改进

Development and Improvement of TOPMODEL

在TOPMODEL模型原理及其特点的基础上,结合塔里木河内陆河流域地区的水文特点,考虑冰雪融水量对产汇流的影响,构建subTOPMODEL子模块,并与TOPMODEL模型松散耦合,即通过改进模型把高纬度冰雪区从流域中区别开来,在一定程度上反映地区流域的异质性,推进该模型向分布式水文模拟的发展,以完善TOP-MODEL模型。把模型应用于清水河流域,对原模型、改进模型、实测值的两两比较分析：整体分析,模拟结果走型匹配较好,但由于在高强度降雨情况下,超渗地面径流对洪峰贡献很大,而TOPMODEL模型基于变源产流面积理论,没有充分考虑超渗地面径流,主洪峰的计算洪峰径流量明显小于实测洪峰流量;改进模型的模拟效率系数effi-ciency为0.738,效率系数结果提高度不是令人满意,仅提高了0.051,但其春冬季节细微表现证实改进模型的有效性。此外,采用的DEM数据及模拟时段步长分别为300 m×300 m和日,有效的模拟结果也为今后进一步拓展TOPMODEL模型在塔里木河流域地区的应用提供了有益的研究经验。

The TOPMODEL which is developed firstly by Beven and Kirkby in 1979 is a variable contributing area conceptual model in which the predominant factors determining the formation of runoff are represented by the topography of the basin and a negative exponential law linking the transmissivity of the soil with the distance to the saturated zone below the ground level. Although conceptual, this model is frequently described as a physically based model in the sense that its parameters can be measured directly in situation. In order to understand and prove the physically based quzi-distributed hydrological model, the authors constructed subtopmodel module to be coupled with topmodel taking the characteristics of topmodel and hydrology of Tarim River which is one of the inland rivers into account to separate ice-snow area from the whole catchment , which physically reflected heterogeneity of the catchment to some extent ,developing topmodel further to distributed hydrological model. And it has therefore been applied to the Qingshui River experimental basin which belongs to the Chinese biggest inland Tarim River catchment. Through analyzing daily runoff between each other,the results of simulation was appreciate for the whole procession though the main flood peak of simulation was smaller than that of measurement because that the topmodel was based on that a large proportion of stream water is generated from saturated contributing areas （source areas） ignoring excess-infiltration which was actually happened when rained heavy. The resuit also proved that the subtopmodel was effective to topmodel though the efficiency of proved-simulation was only 0. 051 higher than that of ori-simulation, which got the clue from simulative procession of spring and winter. Further more it provided useful insights into the structure of the model and its feasibility to inland rivers in northwest of China based on 300 m× 300 m DEM resolution and time interval of day, which provided good experience for applying topmodel to Tarim River basin in the future hydrology studying.