水文模型中DEM低洼地处理的新算法  

A New Algorithm for DEM Depressions Processing in Hydrological Models

作　　者：程品[1] 孙法圣[1] 张博[1] 郭志慧 

机构地区：[1]吉林大学环境与资源学院,长春130021 [2]辽宁省核工业地质局,辽宁凤城118100

出　　处：《中国农村水利水电》2014年第5期38-41,44,共5页China Rural Water and Hydropower

摘　　要：DEM数据作为基本地形信息的载体,被广泛应用于分布式水文模型中。但是由于各种人为的和自然的原因,DEM中普遍存在着许多大小不等的低洼地(包括洼地和平地),为水系的生成和汇流计算造成障碍。因此,DEM中低洼地的预处理是使用DEM进行水文模拟的前提。采用新的洼地填充算法(溢水法)填平洼地,并提出独创的"出口汇聚流向模式"为平地区域设置坡度,将平地中的水导出。该方法与传统填充法相比简单明了,不需要计算水流方向,也不需要考虑复合洼地的嵌套关系。整套处理方法经编程实现,并由实例验证其可靠性。使用这套算法处理后的DEM中,任何一点的流向都是确定的,而整体地貌对比于处理前的改变接近最小。使用该方法处理得到的DEM能够满足分布式水文模型中洪水汇流计算的需要。DEM is widely used in distributed hydrological models as the basic topographic information carrier. Because of various man -made and natural causes, many depressions of every size （including depressions and flat areas） are widespread in DEM. That causes an obstacle for river network generation and concentration calculation. So, preproeessing depressions in DEM is the premise of all the other work in flood simulation. In this paper, a innovative depression filling algorithm（overflow method）is proposed to process de- pressions, and an improved outlet-collect flow direction mode is put forward to assign tiny slopes for flat area. In this way, water is exported from flat areas fluently. Compared with traditional algorithms, this method is simple and clear. There is no need to calcu- late the flow direction and it is easy to deal with depressions nesting structure. This method proves to be reliable after the verification of programming and example. The difference between the original DEM and the processed one is tiniest. DEM processed by this method can be used for flood concentration calculation in distributed hydrolo~：ical models in a watershed.

关 键 词：DEM 水文模型 洼地 溢水法 出口汇聚流向模式 

分 类 号：P341[天文地球—水文科学]