【作者】 李建柱；

【导师】 冯平；

【作者基本信息】 天津大学 ， 水利水电工程， 2005， 硕士

【摘要】 本文对集总式水文模型和分布式水文模型进行了对比,指出集总式水文模型一般是将流域作为一个整体,由流域的平均降雨过程推求流域出口断面的流量过程,而分布式水文模型能充分考虑降雨和流域下垫面的分布不均匀性,能揭示水文循环的物理机制。阐述了集总式水文模型和分布式水文模型在建模思路与水文循环模拟过程的不同之处。强调了分布式水文模型在模拟降雨径流过程中的优越性。主要内容如下:(1)基于滦河流域栅格DEM数据,采用地理信息系统软件,根据地形提取水系信息,提取出的信息可以直接被水文模型所调用,不仅可以大大提高水文模拟的效率,而且还可以方便的利用遥感等数据源,丰富建模信息,并为分布式水文模型的研制提供了平台。经过对DEM的预处理、采用最陡坡度法确定水流方向、计算集水面积等步骤,自动提取出了滦河流域的水系。提取出的水系和原水系基本一致,能够达到令人满意的程度。(2)在提取的流域水系的基础上,通过对流域模型部分参数的率定,计算各子流域蒸发量、下渗量,将Topmodel模型应用到滦河流域,模拟计算结果能控制在一定的误差范围内,说明模型结构合理,模拟原理基本符合实际情况。影响模型实际效果的主要因素是流域内降水,经过分布的降水量并不能代表实际降水量,尤其是涉及流域面积较大,降雨观测站少。建立分布式水文模型的目的就是要从降雨的空间不均匀性和不同下垫面角度探讨水文循环过程和水文循环机理。计算机、GIS和RS的不断发展,必然会推动分布式水文模型,特别是基于DEM网格的分布式水文模型更快速地发展。基于DEM网格的水文模型将是未来流域水文模型发展的主方向。更多还原

【Abstract】 Lumped hydrologic model is compared with distributed hydrologic model in thisthesis. Differences are presented between these two kinds of models in modellingmethods and in runoff generation mechanism. The watershed is usually considered asa whole in lumped hydrologic model, while in distributed hydrologic model thewatershed is divided into many grids or subcatchments. The priority of distributedhydrologic model is emphersized. The following outcomes and conclusions areobtained.(1) Based on grid DEM data of Luanhe river basin, the stream networks are extractedby GIS which can be used in hydrologic model directly. Thus , the modellingeffeciecy is developed obviously and RS data can be offered in the modelling.Through the procedure of pre-treatment of DEM, deciding the flow direction andcalculating the contributing area, the stream networks is extracted, which is in goodagreement to the reality.(2) After optimizing some variables of the model, evaporation and infiltration in thewatershed can be calculated. Topmodel is applied to Luanhe watershed, and theresults can be controled in a certain error. So we can say the model structure isreasonable and the principle is consistent with the reality. The main factor whichinfluences the modelling precision is rainfall, because of the distributed rainfallartificially, especially in such a large watershed. The purpose of building distributedhydrologic model is to search the mechanism and the process of water cycle byconsidering the spacial asymmetry. With the development of computer science, geographical information system andremote sensing, distributed hydrologic model, especially the one based on DEM, mustbe developed quickly. We believe that distributed hydrologic models based on DEMwill be the main direction in the future.更多还原