摘 要：数字高程模型（DEM）是重要的空间数据，更是流域分析的主要数据来源，提供了丰富的地质地貌和水文特征信息。基于DEM的流域特征的自动提取是流域数字化研究的重点，流域水文信息是建立水文模型的重要数据支撑，建立完善的水文模型有利于水资源利用、生态保护、农业生产等方面的发展，因此对于河网水系的信息提取和特征分析具有重要的理论价值和社会意义。本文以黄山地表水文流域为例，采用ArcGIS软件的水文分析模块详细介绍了基于DEM提取水文特征并生成河网的方法，包括流向计算、洼地判定、洼地填充、计算水流长度、汇流分析、河网的生成和分级、子流域的划分和分类。研究表明，黄山地表河网水系起伏交错，经过反复试验，阈值为1000时提取的河网最符合实际情况。流域整体河网密度较大，多为狭长型小流域，植被破坏和水土流失严重。77457

毕业论文关键词：DEM，流域特征，水文分析，河网分级，子流域

Abstract：Digital elevation model (DEM) is an important spatial data, it is the main data source of watershed analysis, and provides a wealth of information on the geological features and hydrological characteristics。 Based on the automatic extraction of watershed characteristics of DEM is the focus of the digitalization of basin, hydrological information is established the important data of hydrological model support, establish perfect hydrological model for the water resources utilization and ecological protection, agricultural production and other aspects of development, so for river drainage network information extraction and feature analysis has important theoretical value and social significance。 The Huangshan surface hydrology, for example by hydrological analysis module of ArcGIS software described in detail based on the method of DEM extraction hydrological characteristics and generate river network, including flow calculations, determine the depression, depression filling, flow length, convergence analysis, network generation and classification, sub basin classification and calculation was introduced in detail。 Studies have shown that Huangshan surface drainage network ups and downs staggered, after repeated tests, the threshold for 1000 extraction of river network accords with the actual situation。 The whole river basin density for narrow small watershed, vegetation destruction and soil erosion。

Keywords：DEM, watershed characteristics, hydrological analysis, stream order, Sub Basin

目   录

1 绪论 4

1。1  问题的提出 4

1。2  研究背景与意义 4

1。3  国内外研究现状 5

2  研究基础 6

2。1  研究区域概况 6

2。2  数据基础 6

2。3  研究方法及技术路线 7

3  黄山区域地表河网提取实现 8

3。1  流域DEM预处理 9

3。2  确定格网水流方向 11

3。3  汇流分析 12

3。4  河网生成及河网分级 14

3。5  精度分析 15

3。6  流域分析 18

3。7  本章小结 19

4  子流域分析