水利学报
水利學報
수리학보
2013年
8期
901-908
,共8页
孙爱立%余钟波%杨传国%谷黄河
孫愛立%餘鐘波%楊傳國%穀黃河
손애립%여종파%양전국%곡황하
河网%阈值%DEM%影响因素
河網%閾值%DEM%影響因素
하망%역치%DEM%영향인소
drainage network%threshold%DEM%impact factors
阈值确定是数字高程模型（DEM）提取水系的重要环节，影响数字流域水系的拓扑关系和几何特征，进而影响流域的坡面和河道汇流过程。选取我国50个子流域作为样本，基于DEM提取河网，确定最佳集水面积阈值，并分析主要空间影响因素；采用相关分析和多元线性回归分析等方法，分析流域降水、地形和地表覆被与河网阈值的关系。结果表明，流域雨量越充沛，地形越陡峭，植被越茂密，集水面积阈值就越小，并得出阈值与降水、坡度和地表覆被的定量关系。该方法应用于其他流域，效果较好。
閾值確定是數字高程模型（DEM）提取水繫的重要環節，影響數字流域水繫的拓撲關繫和幾何特徵，進而影響流域的坡麵和河道彙流過程。選取我國50箇子流域作為樣本，基于DEM提取河網，確定最佳集水麵積閾值，併分析主要空間影響因素；採用相關分析和多元線性迴歸分析等方法，分析流域降水、地形和地錶覆被與河網閾值的關繫。結果錶明，流域雨量越充沛，地形越陡峭，植被越茂密，集水麵積閾值就越小，併得齣閾值與降水、坡度和地錶覆被的定量關繫。該方法應用于其他流域，效果較好。
역치학정시수자고정모형（DEM）제취수계적중요배절，영향수자류역수계적탁복관계화궤하특정，진이영향류역적파면화하도회류과정。선취아국50개자류역작위양본，기우DEM제취하망，학정최가집수면적역치，병분석주요공간영향인소；채용상관분석화다원선성회귀분석등방법，분석류역강수、지형화지표복피여하망역치적관계。결과표명，류역우량월충패，지형월두초，식피월무밀，집수면적역치취월소，병득출역치여강수、파도화지표복피적정량관계。해방법응용우기타류역，효과교호。
Determination of threshold plays an important role in extracting drainage network based on DEM and affects the topological and geometric characteristics of the digital river system, thereby affecting hill-slope and fluvial process. In this paper,50 sub-basins were selected as the sample to extract drainage net-work based on DEM and to determine the best critical contribution area whose main spatial impact factors were analyzed. The relationships among precipitation,topography,land surface cover and threshold were in-vestigated by using correlation analysis and multiple linear regression analysis. The results show that the critical contribution area decreases with the increasing precipitation, slope and the total area index (TAI), and the quantitative equation of the threshold and precipitation,slope,and land surface cover has been es-tablished. The equation has a good behavior in other watersheds making the determination of the threshold more objective and convenient.
