An Analysis of the Hydrological Runoff System Based on the Digital National Land Information

本研究利用通用计算机和建设部地质调查院发布的全国土地信息数字系统开发了两个系统。一个是分析流域地貌特征和河道网络的自动数据处理系统，另一个是考虑自然流域地形的流域建模自动生成系统。流域及河道网地貌特征分析的自动数据处理系统该系统可以比传统方法更客观、更自动地分析地貌特征，显示流域的三维结构，并自动计算基于Horton-Strahler流数和链接量级的各种特征值。对10个流域（190 ~ 870 Km^2）的这些值进行了计算和比较。考虑自然流域地形的流域建模自动生成系统，该系统以基于网格的DEM （Digital Elevation model）生成的三角元表示流域的地形面。将覆盖三角形单元的流域划分为多个坡元，计算每个坡元的径流高度。利用国家土地数字信息对伊纳河流域进行了应用，验证了该方法的有效性。

In this research, two systems using general purpose computers and the Digital National Land Information released by the Geological Surveying Institute, the Ministry of Construction are developed. One is an automatic data processing system for analysis of geomorphologic features of drainage basins and channel networks, and the other is an automatic generating system for modeling of drainage basins which consider the topography of natural watershed.1. Automatic data processing system for analysis of geomorphologic features of drainage basins and channel networksThe system makes it possible to analyze the geomorphologic features more objectively and automatically than a conventional method and to show a three-dimensional structure of a basin, and various characteristic values based on the Horton-Strahler stream number and link magnitude are calculated automatically. These values in ten river basins (190-870 Km^2) are calculated and compared.2. Automatic generating system for modeling of drainage basins which consider the topography of natural watershedIn this system, the topographic surface of a basin is represented by trianguler elements which are generated from grid based DEM (Digital Elevation model). A basin coverd with triangular elements is divided into slope elements and runoff height of every slope element is calculated.This method is applied to the Ina River Basin using the Digital National Land Information, and the availability of this method is confirmed.